eventespresso / event-espresso-core

core/services/database/WpdbDataFormat.php

Indentation +50 added lines, -50 removed lines

@@ -8,65 +8,65 @@
 
 class WpdbDataFormat
 {
-    /**
-     * used for table/field names
-     */
-    const IDENTIFIER = '%i';
+	/**
+	 * used for table/field names
+	 */
+	const IDENTIFIER = '%i';
 
-    const INTEGER    = '%d';
+	const INTEGER    = '%d';
 
-    const FLOAT      = '%f';
+	const FLOAT      = '%f';
 
-    const STRING     = '%s';
+	const STRING     = '%s';
 
 
-    /**
-     * Return `%d`, `%s` or `%f` to indicate the data type for the field that should be indicated in wpdb queries.
-     *
-     * @param string $type Included if a specific type is requested.
-     * @return string
-     * @uses get_schema_type()
-     */
-    public static function getWpdbDataType(string $type = ''): string
-    {
-        switch ($type) {
-            case SchemaType::BOOLEAN:
-            case SchemaType::INTEGER:
-                return WpdbDataFormat::INTEGER; // '%d'
-            case SchemaType::DB_FIELD:
-                return WpdbDataFormat::IDENTIFIER; // '%i'
-            case SchemaType::NUMBER:
-                return WpdbDataFormat::FLOAT; // '%f'
-            case SchemaType::STRING:
-            default:
-                return WpdbDataFormat::STRING; // '%s'
-        }
-    }
+	/**
+	 * Return `%d`, `%s` or `%f` to indicate the data type for the field that should be indicated in wpdb queries.
+	 *
+	 * @param string $type Included if a specific type is requested.
+	 * @return string
+	 * @uses get_schema_type()
+	 */
+	public static function getWpdbDataType(string $type = ''): string
+	{
+		switch ($type) {
+			case SchemaType::BOOLEAN:
+			case SchemaType::INTEGER:
+				return WpdbDataFormat::INTEGER; // '%d'
+			case SchemaType::DB_FIELD:
+				return WpdbDataFormat::IDENTIFIER; // '%i'
+			case SchemaType::NUMBER:
+				return WpdbDataFormat::FLOAT; // '%f'
+			case SchemaType::STRING:
+			default:
+				return WpdbDataFormat::STRING; // '%s'
+		}
+	}
 
 
-    public static function getWpdbDataTypeForTypeArray(array $type): string
-    {
-        // first let's flip because then we can do a faster key check
-        $type = array_flip($type);
+	public static function getWpdbDataTypeForTypeArray(array $type): string
+	{
+		// first let's flip because then we can do a faster key check
+		$type = array_flip($type);
 
-        // check for things that mean '%s'
-        if (isset($type[SchemaType::STRING], $type[SchemaType::OBJECT], $type[SchemaType::ARRAY])) {
-            return WpdbDataFormat::STRING;
-        }
+		// check for things that mean '%s'
+		if (isset($type[SchemaType::STRING], $type[SchemaType::OBJECT], $type[SchemaType::ARRAY])) {
+			return WpdbDataFormat::STRING;
+		}
 
-        // if makes it past the above condition and there's float in the array
-        // then the type is %f
-        if (isset($type[SchemaType::NUMBER])) {
-            return WpdbDataFormat::FLOAT;
-        }
+		// if makes it past the above condition and there's float in the array
+		// then the type is %f
+		if (isset($type[SchemaType::NUMBER])) {
+			return WpdbDataFormat::FLOAT;
+		}
 
-        // if it makes it past the above conditions and there is an integer in the array
-        // then the type is %d
-        if (isset($type[SchemaType::INTEGER])) {
-            return WpdbDataFormat::INTEGER;
-        }
+		// if it makes it past the above conditions and there is an integer in the array
+		// then the type is %d
+		if (isset($type[SchemaType::INTEGER])) {
+			return WpdbDataFormat::INTEGER;
+		}
 
-        // anything else is a string
-        return WpdbDataFormat::STRING;
-    }
+		// anything else is a string
+		return WpdbDataFormat::STRING;
+	}
 }

core/EE_Registry.core.php

Indentation +1700 added lines, -1700 removed lines

@@ -22,1704 +22,1704 @@
  */
 class EE_Registry implements ResettableInterface
 {
-    private static ?EE_Registry $_instance = null;
-
-    protected EE_Dependency_Map $_dependency_map;
-
-    private Mirror $mirror;
-
-    private ClassInterfaceCache $class_cache;
-
-    private ObjectIdentifier $object_identifier;
-
-    protected array $_class_abbreviations = [];
-
-    public ?CommandBusInterface $BUS = null;
-
-    public ?EE_Cart $CART = null;
-
-    public ?EE_Config $CFG = null;
-
-    public ?EE_Network_Config $NET_CFG = null;
-
-    /**
-     * RegistryContainer for storing library classes in
-     *
-     * @var RegistryContainer|null $LIB
-     */
-    public ?RegistryContainer $LIB = null;
-
-    /**
-     * @var EE_Request_Handler|null $REQ
-     * @deprecated 4.10.14.p
-     */
-    public ?EE_Request_Handler $REQ = null;
-
-    public ?EE_Session $SSN = null;
-
-    /**
-     * @since 4.5.0
-     * @var EE_Capabilities|null $CAP
-     */
-    public ?EE_Capabilities$CAP = null;
-
-    /**
-     * @since 4.9.0
-     * @var EE_Message_Resource_Manager|null $MRM
-     */
-    public ?EE_Message_Resource_Manager $MRM = null;
-
-    public ?Registry $AssetsRegistry = null;
-
-    /**
-     * RegistryContainer for holding addons which have registered themselves to work with EE core
-     *
-     * @var RegistryContainer|EE_Addon[] $addons
-     */
-    public $addons = [];
-
-    /**
-     * keys are 'short names' (eg Event), values are class names (eg 'EEM_Event')
-     *
-     * @var EEM_Base[] $models
-     */
-    public array $models = [];
-
-    /**
-     * @var RegistryContainer|EED_Module[] $modules
-     */
-    public $modules = [];
-
-    /**
-     * @var RegistryContainer|EES_Shortcode[] $shortcodes
-     */
-    public $shortcodes = [];
-
-    /**
-     * @var RegistryContainer|WP_Widget[] $widgets
-     */
-    public $widgets = [];
-
-    /**
-     * this is an array of all implemented model names (i.e. not the parent abstract models, or models
-     * which don't actually fetch items from the DB in the normal way (ie, are not children of EEM_Base)).
-     * Keys are model "short names" (eg "Event") as used in model relations, and values are
-     * classnames (eg "EEM_Event")
-     *
-     * @var array $non_abstract_db_models
-     */
-    public array $non_abstract_db_models = [];
-
-    /**
-     * internationalization for JS strings
-     *    usage:   EE_Registry::i18n_js_strings['string_key'] = esc_html__( 'string to translate.', 'event_espresso' );
-     *    in js file:  var translatedString = eei18n.string_key;
-     *
-     * @var array $i18n_js_strings
-     */
-    public static array $i18n_js_strings = [];
-
-    /**
-     * $main_file - path to espresso.php
-     *
-     * @var string $main_file
-     */
-    public string $main_file = '';
-
-    /**
-     * boolean flag to indicate whether to load/save dependencies from/to the cache
-     *
-     * @var bool $_cache_on
-     */
-    protected bool $_cache_on = true;
-
-
-    /**
-     * @singleton method used to instantiate class object
-     * @param EE_Dependency_Map|null   $dependency_map
-     * @param Mirror|null              $mirror
-     * @param ClassInterfaceCache|null $class_cache
-     * @param ObjectIdentifier|null    $object_identifier
-     * @return EE_Registry instance
-     */
-    public static function instance(
-        EE_Dependency_Map $dependency_map = null,
-        Mirror $mirror = null,
-        ClassInterfaceCache $class_cache = null,
-        ObjectIdentifier $object_identifier = null
-    ): EE_Registry {
-        // check if class object is instantiated
-        if (
-            ! self::$_instance instanceof EE_Registry
-            && $dependency_map instanceof EE_Dependency_Map
-            && $mirror instanceof Mirror
-            && $class_cache instanceof ClassInterfaceCache
-            && $object_identifier instanceof ObjectIdentifier
-        ) {
-            self::$_instance = new self(
-                $dependency_map,
-                $mirror,
-                $class_cache,
-                $object_identifier
-            );
-        }
-        return self::$_instance;
-    }
-
-
-    /**
-     * protected constructor to prevent direct creation
-     *
-     * @Constructor
-     * @param EE_Dependency_Map   $dependency_map
-     * @param Mirror              $mirror
-     * @param ClassInterfaceCache $class_cache
-     * @param ObjectIdentifier    $object_identifier
-     */
-    protected function __construct(
-        EE_Dependency_Map $dependency_map,
-        Mirror $mirror,
-        ClassInterfaceCache $class_cache,
-        ObjectIdentifier $object_identifier
-    ) {
-        $this->_dependency_map   = $dependency_map;
-        $this->mirror            = $mirror;
-        $this->class_cache       = $class_cache;
-        $this->object_identifier = $object_identifier;
-
-        $this->LIB        = new RegistryContainer();
-        $this->addons     = new RegistryContainer();
-        $this->modules    = new RegistryContainer();
-        $this->shortcodes = new RegistryContainer();
-        $this->widgets    = new RegistryContainer();
-        add_action('EE_Load_Espresso_Core__handle_request__initialize_core_loading', [$this, 'initialize']);
-    }
-
-
-    /**
-     * initialize
-     *
-     * @throws OutOfBoundsException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function initialize()
-    {
-        $this->_class_abbreviations = apply_filters(
-            'FHEE__EE_Registry____construct___class_abbreviations',
-            [
-                'EE_Config'                                       => 'CFG',
-                'EE_Session'                                      => 'SSN',
-                'EE_Capabilities'                                 => 'CAP',
-                'EE_Cart'                                         => 'CART',
-                'EE_Network_Config'                               => 'NET_CFG',
-                'EE_Request_Handler'                              => 'REQ',
-                'EE_Message_Resource_Manager'                     => 'MRM',
-                'EventEspresso\core\services\commands\CommandBus' => 'BUS',
-                'EventEspresso\core\services\assets\Registry'     => 'AssetsRegistry',
-            ]
-        );
-        $this->load_core('Base', [], true);
-        // add our request and response objects to the cache
-        $request_loader = $this->_dependency_map->class_loader(
-            'EventEspresso\core\services\request\Request'
-        );
-        $this->_set_cached_class(
-            $request_loader(),
-            'EventEspresso\core\services\request\Request'
-        );
-        $response_loader = $this->_dependency_map->class_loader(
-            'EventEspresso\core\services\request\Response'
-        );
-        $this->_set_cached_class(
-            $response_loader(),
-            'EventEspresso\core\services\request\Response'
-        );
-        add_action('AHEE__EE_System__set_hooks_for_core', [$this, 'init']);
-    }
-
-
-    /**
-     * @return void
-     */
-    public function init()
-    {
-        // Get current page protocol
-        $protocol = is_ssl() ? 'https://' : 'http://';
-        // Output admin-ajax.php URL with same protocol as current page
-        self::$i18n_js_strings['ajax_url'] = admin_url('admin-ajax.php', $protocol);
-        self::$i18n_js_strings['wp_debug'] = defined('WP_DEBUG') && WP_DEBUG;
-    }
-
-
-    /**
-     * @return array
-     */
-    public static function sanitize_i18n_js_strings(): array
-    {
-        array_walk(EE_Registry::$i18n_js_strings, function (&$value) {
-            if (is_scalar($value)) {
-                $value = html_entity_decode((string) $value, ENT_QUOTES, 'UTF-8');
-                // replace all escaped instances of \n with actual new lines
-                $value = str_replace("\\n", "\n", $value);
-            }
-        });
-        // sort the array by key in a case-insensitive manner
-        ksort(EE_Registry::$i18n_js_strings, SORT_NATURAL | SORT_FLAG_CASE);
-        return EE_Registry::$i18n_js_strings;
-    }
-
-
-    /**
-     * localize_i18n_js_strings
-     *
-     * @return string
-     */
-    public static function localize_i18n_js_strings(): string
-    {
-        $i18n_js_strings = wp_json_encode(EE_Registry::sanitize_i18n_js_strings());
-        return "/* <![CDATA[ */ var eei18n = $i18n_js_strings; /* ]]> */";
-    }
-
-
-    /**
-     * @param mixed string | EED_Module $module
-     * @throws OutOfBoundsException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function add_module($module)
-    {
-        if ($module instanceof EED_Module) {
-            $module_class = get_class($module);
-            $this->modules->add($module_class, $module);
-        } else {
-            if (! class_exists('EE_Module_Request_Router', false)) {
-                $this->load_core('Module_Request_Router');
-            }
-            EE_Module_Request_Router::module_factory($module);
-        }
-    }
-
-
-    /**
-     * @param string $module_name
-     * @return mixed EED_Module | NULL
-     */
-    public function get_module(string $module_name = '')
-    {
-        return $this->modules->get($module_name);
-    }
-
-
-    /**
-     * loads core classes - must be singletons
-     *
-     * @param string $class_name - simple class name ie: session
-     * @param mixed  $arguments
-     * @param bool   $load_only
-     * @return bool|null|object
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     */
-    public function load_core(string $class_name, $arguments = [], bool $load_only = false)
-    {
-        $core_paths = (array) apply_filters(
-            'FHEE__EE_Registry__load_core__core_paths',
-            [
-                EE_CORE,
-                EE_ADMIN,
-                EE_CPTS,
-                EE_CORE . 'CPTs/',
-                EE_CORE . 'data_migration_scripts/',
-                EE_CORE . 'request_stack/',
-                EE_CORE . 'middleware/',
-            ]
-        );
-        // retrieve instantiated class
-        return $this->_load(
-            $core_paths,
-            'EE_',
-            $class_name,
-            'core',
-            $arguments,
-            false,
-            true,
-            $load_only
-        );
-    }
-
-
-    /**
-     * loads service classes
-     *
-     * @param string $class_name - simple class name ie: session
-     * @param mixed  $arguments
-     * @param bool   $load_only
-     * @return bool|null|object
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @deprecated  4.10.33.p
-     */
-    public function load_service(string $class_name, $arguments = [], bool $load_only = false)
-    {
-        $service_paths = (array) apply_filters(
-            'FHEE__EE_Registry__load_service__service_paths',
-            [
-                EE_CORE . 'services/',
-            ]
-        );
-        // retrieve instantiated class
-        return $this->_load(
-            $service_paths,
-            'EE_',
-            $class_name,
-            'class',
-            $arguments,
-            false,
-            true,
-            $load_only
-        );
-    }
-
-
-    /**
-     * loads data_migration_scripts
-     *
-     * @param string $class_name - class name for the DMS ie: EE_DMS_Core_4_2_0
-     * @param mixed  $arguments
-     * @return bool|null|object
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     */
-    public function load_dms(string $class_name, $arguments = [])
-    {
-        // retrieve instantiated class
-        return $this->_load(
-            EE_Data_Migration_Manager::instance()->get_data_migration_script_folders(),
-            'EE_DMS_',
-            $class_name,
-            'dms',
-            $arguments,
-            false,
-            false
-        );
-    }
-
-
-    /**
-     * loads object creating classes - must be singletons
-     *
-     * @param string $class_name - simple class name ie: attendee
-     * @param mixed  $arguments  - an array of arguments to pass to the class
-     * @param bool   $from_db    - some classes are instantiated from the db and thus call a different method to
-     *                           instantiate
-     * @param bool   $cache      if you don't want the class to be stored in the internal cache (non-persistent) then
-     *                           set this to FALSE (ie. when instantiating model objects from client in a loop)
-     * @param bool   $load_only  whether or not to just load the file and NOT instantiate, or load AND instantiate
-     *                           (default)
-     * @return EE_Base_Class|object|bool|null
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     */
-    public function load_class(
-        string $class_name,
-        $arguments = [],
-        bool $from_db = false,
-        bool $cache = true,
-        bool $load_only = false
-    ) {
-        $paths = (array) apply_filters(
-            'FHEE__EE_Registry__load_class__paths',
-            [
-                EE_CORE,
-                EE_CLASSES,
-                EE_BUSINESS,
-            ]
-        );
-        // retrieve instantiated class
-        return $this->_load(
-            $paths,
-            'EE_',
-            $class_name,
-            'class',
-            $arguments,
-            $from_db,
-            $cache,
-            $load_only
-        );
-    }
-
-
-    /**
-     * loads helper classes - must be singletons
-     *
-     * @param string $class_name - simple class name ie: price
-     * @param mixed  $arguments
-     * @param bool   $load_only
-     * @return bool|null|object
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     */
-    public function load_helper(string $class_name, $arguments = [], bool $load_only = true)
-    {
-        // todo: add doing_it_wrong() in a few versions after all addons have had calls to this method removed
-        $helper_paths = (array) apply_filters('FHEE__EE_Registry__load_helper__helper_paths', [EE_HELPERS]);
-        // retrieve instantiated class
-        return $this->_load(
-            $helper_paths,
-            'EEH_',
-            $class_name,
-            'helper',
-            $arguments,
-            false,
-            true,
-            $load_only
-        );
-    }
-
-
-    /**
-     * loads core classes - must be singletons
-     *
-     * @param string $class_name - simple class name ie: session
-     * @param mixed  $arguments
-     * @param bool   $load_only
-     * @param bool   $cache      whether to cache the object or not.
-     * @return bool|null|object
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     */
-    public function load_lib(string $class_name, $arguments = [], bool $load_only = false, bool $cache = true)
-    {
-        $paths = [
-            EE_LIBRARIES,
-            EE_LIBRARIES . 'messages/',
-            EE_LIBRARIES . 'shortcodes/',
-            EE_LIBRARIES . 'qtips/',
-            EE_LIBRARIES . 'payment_methods/',
-        ];
-        // retrieve instantiated class
-        return $this->_load(
-            $paths,
-            'EE_',
-            $class_name,
-            'lib',
-            $arguments,
-            false,
-            $cache,
-            $load_only
-        );
-    }
-
-
-    /**
-     * loads model classes - must be singletons
-     *
-     * @param string $class_name - simple class name ie: price
-     * @param mixed  $arguments
-     * @param bool   $load_only
-     * @return EEM_Base|null
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     */
-    public function load_model(string $class_name, $arguments = [], bool $load_only = false): ?EEM_Base
-    {
-        // retrieve instantiated class
-        $model = $this->_load(
-            (array) apply_filters(
-                'FHEE__EE_Registry__load_model__paths',
-                [
-                    EE_MODELS,
-                    EE_CORE,
-                ]
-            ),
-            'EEM_',
-            $class_name,
-            'model',
-            $arguments,
-            false,
-            true,
-            $load_only
-        );
-        return $model instanceof EEM_Base ? $model : null;
-    }
-
-
-    /**
-     * loads model classes - must be singletons
-     *
-     * @param string $class_name - simple class name ie: price
-     * @param mixed  $arguments
-     * @param bool   $load_only
-     * @return bool|null|object
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @deprecated  4.10.33.p
-     */
-    public function load_model_class(string $class_name, $arguments = [], bool $load_only = true)
-    {
-        $paths = [
-            EE_MODELS . 'fields/',
-            EE_MODELS . 'helpers/',
-            EE_MODELS . 'relations/',
-            EE_MODELS . 'strategies/',
-        ];
-        // retrieve instantiated class
-        return $this->_load(
-            $paths,
-            'EE_',
-            $class_name,
-            '',
-            $arguments,
-            false,
-            true,
-            $load_only
-        );
-    }
-
-
-    /**
-     * Determines if $model_name is the name of an actual EE model.
-     *
-     * @param string $model_name like Event, Attendee, Question_Group_Question, etc.
-     * @return boolean
-     */
-    public function is_model_name(string $model_name): bool
-    {
-        return isset($this->models[ $model_name ]);
-    }
-
-
-    /**
-     * generic class loader
-     *
-     * @param string $path_to_file - directory path to file location, not including filename
-     * @param string $file_name    - file name  ie:  my_file.php, including extension
-     * @param string $type         - file type - core? class? helper? model?
-     * @param mixed  $arguments
-     * @param bool   $load_only
-     * @return bool|null|object
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     */
-    public function load_file(
-        string $path_to_file,
-        string $file_name,
-        string $type = '',
-        $arguments = [],
-        bool $load_only = true
-    ) {
-        // retrieve instantiated class
-        return $this->_load(
-            (array) $path_to_file,
-            '',
-            $file_name,
-            $type,
-            $arguments,
-            false,
-            true,
-            $load_only
-        );
-    }
-
-
-    /**
-     * @param string $path_to_file - directory path to file location, not including filename
-     * @param string $class_name   - full class name  ie:  My_Class
-     * @param string $type         - file type - core? class? helper? model?
-     * @param mixed  $arguments
-     * @param bool   $load_only
-     * @return bool|null|object
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @deprecated  4.10.33.p
-     */
-    public function load_addon(
-        string $path_to_file,
-        string $class_name,
-        string $type = 'class',
-        $arguments = [],
-        bool $load_only = false
-    ) {
-        // retrieve instantiated class
-        return $this->_load(
-            (array) $path_to_file,
-            'addon',
-            $class_name,
-            $type,
-            $arguments,
-            false,
-            true,
-            $load_only
-        );
-    }
-
-
-    /**
-     * instantiates, caches, and automatically resolves dependencies
-     * for classes that use a Fully Qualified Class Name.
-     * if the class is not capable of being loaded using PSR-4 autoloading,
-     * then you need to use one of the existing load_*() methods
-     * which can resolve the classname and filepath from the passed arguments
-     *
-     * @param string      $class_name Fully Qualified Class Name
-     * @param array       $arguments  an argument, or array of arguments to pass to the class upon instantiation
-     * @param bool        $cache      whether to cache the instantiated object for reuse
-     * @param bool        $from_db    some classes are instantiated from the db
-     *                                and thus call a different method to instantiate
-     * @param bool        $load_only  if true, will only load the file, but will NOT instantiate an object
-     * @param bool|string $addon      if true, will cache the object in the EE_Registry->$addons array
-     * @return bool|null|mixed     null = failure to load or instantiate class object.
-     *                                object = class loaded and instantiated successfully.
-     *                                bool = fail or success when $load_only is true
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     */
-    public function create(
-        string $class_name = '',
-        array $arguments = [],
-        bool $cache = false,
-        bool $from_db = false,
-        bool $load_only = false,
-        bool $addon = false
-    ) {
-        $class_name   = ltrim($class_name, '\\');
-        $class_name   = $this->class_cache->getFqnForAlias($class_name);
-        $class_exists = $this->loadOrVerifyClassExists($class_name, $arguments);
-        // if a non-FQCN was passed, then
-        // verifyClassExists() might return an object
-        // or it could return null if the class just could not be found anywhere
-        if ($class_exists instanceof $class_name || $class_exists === null) {
-            // either way, return the results
-            return $class_exists;
-        }
-        $class_name = $class_exists;
-        // if we're only loading the class and it already exists, then let's just return true immediately
-        if ($load_only) {
-            return true;
-        }
-        $addon = $addon ? 'addon' : '';
-        // $this->_cache_on is toggled during the recursive loading that can occur with dependency injection
-        // $cache is controlled by individual calls to separate Registry loader methods like load_class()
-        // $load_only is also controlled by individual calls to separate Registry loader methods like load_file()
-        if ($this->_cache_on && $cache) {
-            // return object if it's already cached
-            $cached_class = $this->_get_cached_class($class_name, $addon, $arguments);
-            if ($cached_class !== null) {
-                return $cached_class;
-            }
-        }                                                           // obtain the loader method from the dependency map
-        $loader = $this->_dependency_map->class_loader($class_name);// instantiate the requested object
-        if ($loader instanceof Closure) {
-            $class_obj = $loader($arguments);
-        } else {
-            if ($loader && method_exists($this, $loader)) {
-                $class_obj = $this->{$loader}($class_name, $arguments);
-            } else {
-                $class_obj = $this->_create_object($class_name, $arguments, $addon, $from_db);
-            }
-        }
-        if (($this->_cache_on && $cache) || $this->get_class_abbreviation($class_name, '')) {
-            // save it for later... kinda like gum  { : $
-            $this->_set_cached_class(
-                $class_obj,
-                $class_name,
-                $addon,
-                $from_db,
-                $arguments
-            );
-        }
-        $this->_cache_on = true;
-        return $class_obj;
-    }
-
-
-    /**
-     * Recursively checks that a class exists and potentially attempts to load classes with non-FQCNs
-     *
-     * @param string|mixed $class_name
-     * @param array        $arguments
-     * @param int          $attempt
-     * @return mixed
-     */
-    private function loadOrVerifyClassExists($class_name, array $arguments, int $attempt = 1)
-    {
-        if (is_object($class_name) || class_exists($class_name)) {
-            return $class_name;
-        }
-        switch ($attempt) {
-            case 1:
-                // if it's a FQCN then maybe the class is registered with a preceding \
-                $class_name = strpos($class_name, '\\') !== false
-                    ? '\\' . ltrim($class_name, '\\')
-                    : $class_name;
-                break;
-            case 2:
-                //
-                $loader = $this->_dependency_map->class_loader($class_name);
-                if ($loader && method_exists($this, $loader)) {
-                    return $this->{$loader}($class_name, $arguments);
-                }
-                break;
-            case 3:
-            default:
-                return null;
-        }
-        $attempt++;
-        return $this->loadOrVerifyClassExists($class_name, $arguments, $attempt);
-    }
-
-
-    /**
-     * instantiates, caches, and injects dependencies for classes
-     *
-     * @param array  $file_paths         an array of paths to folders to look in
-     * @param string $class_prefix       EE  or EEM or... ???
-     * @param string $class_name         $class name
-     * @param string $type               file type - core? class? helper? model?
-     * @param mixed  $arguments          an argument or array of arguments to pass to the class upon instantiation
-     * @param bool   $from_db            some classes are instantiated from the db
-     *                                   and thus call a different method to instantiate
-     * @param bool   $cache              whether to cache the instantiated object for reuse
-     * @param bool   $load_only          if true, will only load the file, but will NOT instantiate an object
-     * @return bool|null|object          null   = failure to load or instantiate class object.
-     *                                   object = class loaded and instantiated successfully.
-     *                                   bool   = fail or success when $load_only is true
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws InvalidArgumentException
-     */
-    protected function _load(
-        array $file_paths = [],
-        string $class_prefix = 'EE_',
-        string $class_name = '',
-        string $type = 'class',
-        array $arguments = [],
-        bool $from_db = false,
-        bool $cache = true,
-        bool $load_only = false
-    ) {
-        $class_name = ltrim($class_name, '\\');
-        // strip php file extension
-        $class_name = str_replace('.php', '', trim($class_name));
-        // does the class have a prefix ?
-        if (! empty($class_prefix) && $class_prefix !== 'addon') {
-            // make sure $class_prefix is uppercase
-            $class_prefix = strtoupper(trim($class_prefix));
-            // add class prefix ONCE!!!
-            $class_name = $class_prefix . str_replace($class_prefix, '', $class_name);
-        }
-        $class_name   = $this->class_cache->getFqnForAlias($class_name);
-        $class_exists = class_exists($class_name, false);
-        // if we're only loading the class and it already exists, then let's just return true immediately
-        if ($load_only && $class_exists) {
-            return true;
-        }
-        $arguments = is_array($arguments) ? $arguments : [$arguments];
-        // $this->_cache_on is toggled during the recursive loading that can occur with dependency injection
-        // $cache is controlled by individual calls to separate Registry loader methods like load_class()
-        // $load_only is also controlled by individual calls to separate Registry loader methods like load_file()
-        if ($this->_cache_on && $cache && ! $load_only) {
-            // return object if it's already cached
-            $cached_class = $this->_get_cached_class($class_name, $class_prefix, $arguments);
-            if ($cached_class !== null) {
-                return $cached_class;
-            }
-        }
-        // if the class doesn't already exist.. then we need to try and find the file and load it
-        if (! $class_exists) {
-            // get full path to file
-            $path = $this->_resolve_path($class_name, $type, $file_paths);
-            // load the file
-            $loaded = $this->_require_file($path, $class_name, $type, $file_paths);
-            // if we are only loading a file but NOT instantiating an object
-            // then return boolean for whether class was loaded or not
-            if ($load_only) {
-                return $loaded;
-            }
-            // if an object was expected but loading failed, then return nothing
-            if (! $loaded) {
-                return null;
-            }
-        }
-        // instantiate the requested object
-        $class_obj = $this->_create_object($class_name, $arguments, $type, $from_db);
-        if ($this->_cache_on && $cache) {
-            // save it for later... kinda like gum  { : $
-            $this->_set_cached_class(
-                $class_obj,
-                $class_name,
-                $class_prefix,
-                $from_db,
-                $arguments
-            );
-        }
-        $this->_cache_on = true;
-        return $class_obj;
-    }
-
-
-    /**
-     * @param string $class_name
-     * @param string $default have to specify something, but not anything that will conflict
-     * @return mixed|string
-     */
-    protected function get_class_abbreviation(string $class_name, string $default = 'FANCY_BATMAN_PANTS')
-    {
-        return $this->_class_abbreviations[ $class_name ] ?? $default;
-    }
-
-
-    /**
-     * attempts to find a cached version of the requested class
-     * by looking in the following places:
-     *        $this->{$class_abbreviation}            ie:    $this->CART
-     *        $this->{$class_name}                        ie:    $this->Some_Class
-     *        $this->LIB->{$class_name}                ie:    $this->LIB->Some_Class
-     *        $this->addon->{$class_name}    ie:    $this->addon->Some_Addon_Class
-     *
-     * @param string $class_name
-     * @param string $class_prefix
-     * @param array  $arguments
-     * @return mixed
-     */
-    protected function _get_cached_class(
-        string $class_name,
-        string $class_prefix = '',
-        array $arguments = []
-    ) {
-        if ($class_name === 'EE_Registry') {
-            return $this;
-        }
-        $class_abbreviation = $this->get_class_abbreviation($class_name);
-        // check if class has already been loaded, and return it if it has been
-        if (isset($this->{$class_abbreviation})) {
-            return $this->{$class_abbreviation};
-        }
-        $class_name = str_replace('\\', '_', $class_name);
-        if (isset($this->{$class_name})) {
-            return $this->{$class_name};
-        }
-        if ($class_prefix === 'addon' && $this->addons->has($class_name)) {
-            return $this->addons->get($class_name);
-        }
-        $object_identifier = $this->object_identifier->getIdentifier($class_name, $arguments);
-        if ($this->LIB->has($object_identifier)) {
-            return $this->LIB->get($object_identifier);
-        }
-        foreach ($this->LIB as $key => $object) {
-            if (
-                // request does not contain new arguments and therefore no args identifier
-                ! $this->object_identifier->hasArguments($object_identifier)
-                // but previously cached class with args was found
-                && $this->object_identifier->fqcnMatchesObjectIdentifier($class_name, $key)
-            ) {
-                return $object;
-            }
-        }
-        return null;
-    }
-
-
-    /**
-     * removes a cached version of the requested class
-     *
-     * @param string  $class_name
-     * @param boolean $addon
-     * @param array   $arguments
-     * @return boolean
-     */
-    public function clear_cached_class(
-        string $class_name,
-        bool $addon = false,
-        array $arguments = []
-    ): bool {
-        $class_abbreviation = $this->get_class_abbreviation($class_name);
-        // check if class has already been loaded, and return it if it has been
-        if (isset($this->{$class_abbreviation})) {
-            $this->{$class_abbreviation} = null;
-            return true;
-        }
-        $class_name = str_replace('\\', '_', $class_name);
-        if (isset($this->{$class_name})) {
-            $this->{$class_name} = null;
-            return true;
-        }
-        if ($addon && $this->addons->has($class_name)) {
-            $this->addons->remove($class_name);
-            return true;
-        }
-        $class_name = $this->object_identifier->getIdentifier($class_name, $arguments);
-        if ($this->LIB->has($class_name)) {
-            $this->LIB->remove($class_name);
-            return true;
-        }
-        return false;
-    }
-
-
-    /**
-     * _set_cached_class
-     * attempts to cache the instantiated class locally
-     * in one of the following places, in the following order:
-     *        $this->{class_abbreviation}   ie:    $this->CART
-     *        $this->{$class_name}          ie:    $this->Some_Class
-     *        $this->addon->{$$class_name}    ie:    $this->addon->Some_Addon_Class
-     *        $this->LIB->{$class_name}     ie:    $this->LIB->Some_Class
-     *
-     * @param object $class_obj
-     * @param string $class_name
-     * @param string $class_prefix
-     * @param bool   $from_db
-     * @param array  $arguments
-     * @return void
-     */
-    protected function _set_cached_class(
-        $class_obj,
-        string $class_name,
-        string $class_prefix = '',
-        bool $from_db = false,
-        array $arguments = []
-    ) {
-        if ($class_name === 'EE_Registry' || empty($class_obj)) {
-            return;
-        }
-        // return newly instantiated class
-        $class_abbreviation = $this->get_class_abbreviation($class_name, '');
-        if ($class_abbreviation) {
-            $this->{$class_abbreviation} = $class_obj;
-            return;
-        }
-        $class_name = str_replace('\\', '_', $class_name);
-        if (property_exists($this, $class_name)) {
-            $this->{$class_name} = $class_obj;
-            return;
-        }
-        if ($class_prefix === 'addon') {
-            $this->addons->add($class_name, $class_obj);
-            return;
-        }
-        if (! $from_db) {
-            $class_name = $this->object_identifier->getIdentifier($class_name, $arguments);
-            $this->LIB->add($class_name, $class_obj);
-        }
-    }
-
-
-    /**
-     * attempts to find a full valid filepath for the requested class.
-     * loops thru each of the base paths in the $file_paths array and appends : "{classname} . {file type} . php"
-     * then returns that path if the target file has been found and is readable
-     *
-     * @param string $class_name
-     * @param string $type
-     * @param array  $file_paths
-     * @return string | bool
-     */
-    protected function _resolve_path(string $class_name, string $type = '', array $file_paths = [])
-    {
-        // make sure $file_paths is an array
-        $file_paths = is_array($file_paths)
-            ? $file_paths
-            : [$file_paths];
-        // cycle thru paths
-        foreach ($file_paths as $key => $file_path) {
-            // convert all separators to proper /, if no filepath, then use EE_CLASSES
-            $file_path = $file_path
-                ? str_replace(['/', '\\'], '/', $file_path)
-                : EE_CLASSES;
-            // prep file type
-            $type = ! empty($type)
-                ? trim($type, '.') . '.'
-                : '';
-            // build full file path
-            $file_paths[ $key ] = rtrim($file_path, '/') . '/' . $class_name . '.' . $type . 'php';
-            // does the file exist and can be read ?
-            if (is_readable($file_paths[ $key ])) {
-                return $file_paths[ $key ];
-            }
-        }
-        return false;
-    }
-
-
-    /**
-     * basically just performs a require_once()
-     * but with some error handling
-     *
-     * @param string $path
-     * @param string $class_name
-     * @param string $type
-     * @param array  $file_paths
-     * @return bool
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    protected function _require_file(string $path, string $class_name, string $type = '', array $file_paths = []): bool
-    {
-        $this->resolve_legacy_class_parent($class_name);
-        // don't give up! you gotta...
-        try {
-            // does the file exist and can it be read ?
-            if (! $path) {
-                // just in case the file has already been autoloaded,
-                // but discrepancies in the naming schema are preventing it from
-                // being loaded via one of the EE_Registry::load_*() methods,
-                // then let's try one last hail mary before throwing an exception
-                // and call class_exists() again, but with autoloading turned ON
-                if (class_exists($class_name)) {
-                    return true;
-                }
-                // so sorry, can't find the file
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            'The %1$s file %2$s could not be located or is not readable due to file permissions. Please ensure that the following filepath(s) are correct: %3$s',
-                            'event_espresso'
-                        ),
-                        trim($type, '.'),
-                        $class_name,
-                        '<br />' . implode(',<br />', $file_paths)
-                    )
-                );
-            }
-            // get the file
-            require_once($path);
-            // if the class isn't already declared somewhere
-            if (class_exists($class_name, false) === false) {
-                // so sorry, not a class
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            'The %s file %s does not appear to contain the %s Class.',
-                            'event_espresso'
-                        ),
-                        $type,
-                        $path,
-                        $class_name
-                    )
-                );
-            }
-        } catch (EE_Error $e) {
-            $e->get_error();
-            return false;
-        }
-        return true;
-    }
-
-
-    /**
-     * Some of our legacy classes that extended a parent class would simply use a require() statement
-     * before their class declaration in order to ensure that the parent class was loaded.
-     * This is not ideal, but it's nearly impossible to determine the parent class of a non-namespaced class,
-     * without triggering a fatal error because the parent class has yet to be loaded and therefore doesn't exist.
-     *
-     * @param string $class_name
-     */
-    protected function resolve_legacy_class_parent(string $class_name = '')
-    {
-        try {
-            $legacy_parent_class_map = [
-                'EE_Payment_Processor' => 'core/business/EE_Processor_Base.class.php',
-            ];
-            if (isset($legacy_parent_class_map[ $class_name ])) {
-                require_once EE_PLUGIN_DIR_PATH . $legacy_parent_class_map[ $class_name ];
-            }
-        } catch (Exception $exception) {
-        }
-    }
-
-
-    /**
-     * _create_object
-     * Attempts to instantiate the requested class via any of the
-     * commonly used instantiation methods employed throughout EE.
-     * The priority for instantiation is as follows:
-     *        - abstract classes or any class flagged as "load only" (no instantiation occurs)
-     *        - model objects via their 'new_instance_from_db' method
-     *        - model objects via their 'new_instance' method
-     *        - "singleton" classes" via their 'instance' method
-     *    - standard instantiable classes via their __constructor
-     * Prior to instantiation, if the classname exists in the dependency_map,
-     * then the constructor for the requested class will be examined to determine
-     * if any dependencies exist, and if they can be injected.
-     * If so, then those classes will be added to the array of arguments passed to the constructor
-     *
-     * @param string $class_name
-     * @param array  $arguments
-     * @param string $type
-     * @param bool   $from_db
-     * @return null|object|bool
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     */
-    protected function _create_object(
-        string $class_name,
-        array $arguments = [],
-        string $type = '',
-        bool $from_db = false
-    ) {
-        // create reflection
-        $reflector = $this->mirror->getReflectionClass($class_name);
-        // make sure arguments are an array
-        $arguments = is_array($arguments)
-            ? $arguments
-            : [$arguments];
-        // and if arguments array is numerically and sequentially indexed, then we want it to remain as is,
-        // else wrap it in an additional array so that it doesn't get split into multiple parameters
-        $arguments = $this->_array_is_numerically_and_sequentially_indexed($arguments)
-            ? $arguments
-            : [$arguments];
-        // attempt to inject dependencies ?
-        if ($this->_dependency_map->has($class_name)) {
-            $arguments = $this->_resolve_dependencies($reflector, $class_name, $arguments);
-        }
-        // instantiate the class if possible
-        if ($reflector->isAbstract()) {
-            // nothing to instantiate, loading file was enough
-            // does not throw an exception so $instantiation_mode is unused
-            // $instantiation_mode = "1) no constructor abstract class";
-            return true;
-        }
-        if (
-            empty($arguments)
-            && $this->mirror->getConstructorFromReflection($reflector) === null
-            && $reflector->isInstantiable()
-        ) {
-            // no constructor = static methods only... nothing to instantiate, loading file was enough
-            // $instantiation_mode = "2) no constructor but instantiable";
-            return $reflector->newInstance();
-        }
-        if ($from_db && method_exists($class_name, 'new_instance_from_db')) {
-            // $instantiation_mode = "3) new_instance_from_db()";
-            return call_user_func_array([$class_name, 'new_instance_from_db'], $arguments);
-        }
-        if (method_exists($class_name, 'new_instance')) {
-            // $instantiation_mode = "4) new_instance()";
-            return call_user_func_array([$class_name, 'new_instance'], $arguments);
-        }
-        if (method_exists($class_name, 'instance')) {
-            // $instantiation_mode = "5) instance()";
-            return call_user_func_array([$class_name, 'instance'], $arguments);
-        }
-        if ($reflector->isInstantiable()) {
-            $args_passed_count = count($arguments);
-            $args_required_count = count($this->mirror->getRequiredParameters($class_name));
-            if ($args_passed_count < $args_required_count) {
-                throw new RuntimeException(
-                    sprintf(
-                        __(
-                            'Invalid arguments supplied for the %1$s class, %2$s were required but %3$s were passed.',
-                            'event_espresso'
-                        ),
-                        $class_name,
-                        $args_required_count,
-                        $args_passed_count
-                    )
-                );
-            }
-            // $instantiation_mode = "6) constructor";
-            return $reflector->newInstanceArgs($arguments);
-        }
-        // heh ? something's not right !
-        throw new EE_Error(
-            sprintf(
-                esc_html__('The %s file %s could not be instantiated.', 'event_espresso'),
-                $type,
-                $class_name
-            )
-        );
-    }
-
-
-    /**
-     * @see http://stackoverflow.com/questions/173400/how-to-check-if-php-array-is-associative-or-sequential
-     * @param array $array
-     * @return bool
-     */
-    protected function _array_is_numerically_and_sequentially_indexed(array $array): bool
-    {
-        return empty($array) || array_keys($array) === range(0, count($array) - 1);
-    }
-
-
-    /**
-     * _resolve_dependencies
-     * examines the constructor for the requested class to determine
-     * if any dependencies exist, and if they can be injected.
-     * If so, then those classes will be added to the array of arguments passed to the constructor
-     * PLZ NOTE: this is achieved by type hinting the constructor params
-     * For example:
-     *        if attempting to load a class "Foo" with the following constructor:
-     *        __construct( Bar $bar_class, Fighter $grohl_class )
-     *        then $bar_class and $grohl_class will be added to the $arguments array,
-     *        but only IF they are NOT already present in the incoming arguments array,
-     *        and the correct classes can be loaded
-     *
-     * @param ReflectionClass $reflector
-     * @param string          $class_name
-     * @param array           $arguments
-     * @return array
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function _resolve_dependencies(
-        ReflectionClass $reflector,
-        string $class_name,
-        array $arguments = []
-    ): array {
-        // let's examine the constructor
-        $constructor = $this->mirror->getConstructorFromReflection($reflector);
-        // whu? huh? nothing?
-        if (! $constructor) {
-            return $arguments;
-        }
-        // get constructor parameters
-        $params = $this->mirror->getParametersFromReflection($reflector);
-        // and the keys for the incoming arguments array so that we can compare existing arguments with what is expected
-        $argument_keys = array_keys($arguments);
-        // now loop thru all the constructors' expected parameters
-        foreach ($params as $index => $param) {
-            try {
-                // is this a dependency for a specific class ?
-                $param_class = $this->mirror->getParameterClassName($param, $class_name, $index);
-            } catch (ReflectionException $exception) {
-                // uh-oh... most likely a legacy class that has not been autoloaded
-                // let's try to derive the classname from what we have now
-                // and hope that the property var name is close to the class name
-                $param_class = $param->getName();
-                $param_class = str_replace('_', ' ', $param_class);
-                $param_class = ucwords($param_class);
-                $param_class = str_replace(' ', '_', $param_class);
-            }
-            // BUT WAIT !!! This class may be an alias for something else (or getting replaced at runtime)
-            $param_class = $this->class_cache->isAlias($param_class, $class_name)
-                ? $this->class_cache->getFqnForAlias($param_class, $class_name)
-                : $param_class;
-            if (
-                // param is not even a class
-                ($param_class === null || $this->parameterIsPrimitive($param_class))
-                // and something already exists in the incoming arguments for this param
-                && array_key_exists($index, $argument_keys)
-                && isset($arguments[ $argument_keys[ $index ] ])
-            ) {
-                // so let's skip this argument and move on to the next
-                continue;
-            }
-            // parameter is type hinted as a class
-            if ($param_class !== null) {
-                // parameter exists as an incoming argument, AND it's the correct class
-                if (
-                    array_key_exists($index, $argument_keys)
-                    && isset($arguments[ $argument_keys[ $index ] ])
-                    && $arguments[ $argument_keys[ $index ] ] instanceof $param_class
-                ) {
-                    // skip this argument and move on to the next
-                    continue;
-                }
-                // parameter should be injected
-                if ($this->_dependency_map->has_dependency_for_class($class_name, $param_class)) {
-                    $arguments = $this->_resolve_dependency(
-                        $class_name,
-                        $param_class,
-                        $arguments,
-                        $index
-                    );
-                }
-            }
-            if (empty($arguments[ $index ])) {
-                $default_value = $this->mirror->getParameterDefaultValue(
-                    $param,
-                    $class_name,
-                    $index
-                );
-                // if there's no default value, and the incoming argument is an array (albeit empty), then use that
-                $arguments[ $index ] = $default_value === null
-                                       && isset($arguments[ $index ])
-                                       && is_array($arguments[ $index ])
-                    ? $arguments[ $index ]
-                    : $default_value;
-            }
-        }
-        return $arguments;
-    }
-
-
-    /**
-     * @param string $class_name
-     * @param string $param_class
-     * @param array  $arguments
-     * @param mixed  $index
-     * @return array
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     */
-    protected function _resolve_dependency(string $class_name, string $param_class, array $arguments, $index): array
-    {
-        $dependency = null;
-        // should dependency be loaded from cache ?
-        $cache_on = $this->_dependency_map->loading_strategy_for_class_dependency(
-            $class_name,
-            $param_class
-        );
-        $cache_on = $cache_on !== EE_Dependency_Map::load_new_object;
-        // we might have a dependency...
-        // let's MAYBE try and find it in our cache if that's what's been requested
-        $cached_class = $cache_on
-            ? $this->_get_cached_class($param_class)
-            : null;
-        // and grab it if it exists
-        if ($cached_class instanceof $param_class) {
-            $dependency = $cached_class;
-        } elseif ($param_class !== $class_name) {
-            // obtain the loader method from the dependency map
-            $loader = $this->_dependency_map->class_loader($param_class);
-            // is loader a custom closure ?
-            if ($loader instanceof Closure) {
-                $dependency = $loader($arguments);
-            } else {
-                // set the cache on property for the recursive loading call
-                $this->_cache_on = $cache_on;
-                // if not, then let's try and load it via the registry
-                if ($loader && method_exists($this, $loader)) {
-                    $dependency = $this->{$loader}($param_class);
-                } else {
-                    $dependency = LoaderFactory::getLoader()->load(
-                        $param_class,
-                        [],
-                        $cache_on
-                    );
-                }
-            }
-        }
-        // did we successfully find the correct dependency ?
-        if ($dependency instanceof $param_class) {
-            // then let's inject it into the incoming array of arguments at the correct location
-            $arguments[ $index ] = $dependency;
-        }
-        return $arguments;
-    }
-
-
-    /**
-     * call any loader that's been registered in the EE_Dependency_Map::$_class_loaders array
-     *
-     * @param string $classname PLEASE NOTE: the class name needs to match what's registered
-     *                          in the EE_Dependency_Map::$_class_loaders array,
-     *                          including the class prefix, ie: "EE_", "EEM_", "EEH_", etc
-     * @param array  $arguments
-     * @return object
-     */
-    public static function factory(string $classname, array $arguments = [])
-    {
-        $loader = self::instance()->_dependency_map->class_loader($classname);
-        if ($loader instanceof Closure) {
-            return $loader($arguments);
-        }
-        if (method_exists(self::instance(), $loader)) {
-            return self::instance()->{$loader}($classname, $arguments);
-        }
-        return null;
-    }
-
-
-    /**
-     * Gets the addon by its class name
-     *
-     * @param string $class_name
-     * @return EE_Addon
-     */
-    public function getAddon(string $class_name): ?EE_Addon
-    {
-        $class_name = str_replace('\\', '_', $class_name);
-        return $this->addons->{$class_name} ?? null;
-    }
-
-
-    /**
-     * removes the addon from the internal cache
-     *
-     * @param string $class_name
-     * @return void
-     */
-    public function removeAddon(string $class_name)
-    {
-        $class_name = str_replace('\\', '_', $class_name);
-        $this->addons->remove($class_name);
-    }
-
-
-    /**
-     * Gets the addon by its name/slug (not classname. For that, just
-     * use the get_addon() method above
-     *
-     * @param string $name
-     * @return EE_Addon
-     */
-    public function get_addon_by_name(string $name): ?EE_Addon
-    {
-        foreach ($this->addons as $addon) {
-            if ($addon->name() === $name) {
-                return $addon;
-            }
-        }
-        return null;
-    }
-
-
-    /**
-     * Gets an array of all the registered addons, where the keys are their names.
-     * (ie, what each returns for their name() function)
-     * They're already available on EE_Registry::instance()->addons as properties,
-     * where each property's name is the addon's classname,
-     * So if you just want to get the addon by classname,
-     * OR use the get_addon() method above.
-     * PLEASE  NOTE:
-     * addons with Fully Qualified Class Names
-     * have had the namespace separators converted to underscores,
-     * so a classname like Fully\Qualified\ClassName
-     * would have been converted to Fully_Qualified_ClassName
-     *
-     * @return EE_Addon[] where the KEYS are the addon's name()
-     */
-    public function get_addons_by_name(): array
-    {
-        $addons = [];
-        foreach ($this->addons as $addon) {
-            $addons[ $addon->name() ] = $addon;
-        }
-        return $addons;
-    }
-
-
-    /**
-     * Resets the specified model's instance AND makes sure EE_Registry doesn't keep
-     * a stale copy of it around
-     *
-     * @param string $model_name
-     * @return EEM_Base
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function reset_model(string $model_name): ?EEM_Base
-    {
-        $model_class_name = strpos($model_name, 'EEM_') !== 0
-            ? "EEM_$model_name"
-            : $model_name;
-        if (! $this->LIB->has($model_class_name)) {
-            return null;
-        }
-        $model = $this->LIB->get($model_class_name);
-        if (! $model instanceof EEM_Base) {
-            return null;
-        }
-        // get that model reset it and make sure we nuke the old reference to it
-        if ($model instanceof $model_class_name && is_callable([$model_class_name, 'reset'])) {
-            $this->LIB->remove($model_class_name);
-            $this->LIB->add($model_class_name, $model->reset());
-        } else {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__('Model %s does not have a method "reset"', 'event_espresso'),
-                    $model_name
-                )
-            );
-        }
-        return $model;
-    }
-
-
-    /**
-     * Resets the registry.
-     * The criteria for what gets reset is based on what can be shared between sites on the same request when
-     * switch_to_blog is used in a multisite install.  Here is a list of things that are NOT reset.
-     * - $_dependency_map
-     * - $_class_abbreviations
-     * - $NET_CFG (EE_Network_Config): The config is shared network wide so no need to reset.
-     * - $REQ:  Still on the same request so no need to change.
-     * - $CAP: There is no site specific state in the EE_Capability class.
-     * - $SSN: Although ideally, the session should not be shared between site switches, we can't reset it because only
-     * one Session can be active in a single request.  Resetting could resolve in "headers already sent" errors.
-     * - $addons:  In multisite, the state of the addons is something controlled via hooks etc in a normal request.  So
-     *             for now, we won't reset the addons because it could break calls to an add-ons class/methods in the
-     *             switch or on the restore.
-     * - $modules
-     * - $shortcodes
-     * - $widgets
-     *
-     * @param boolean $hard             [deprecated]
-     * @param boolean $reinstantiate    whether to create new instances of EE_Registry's singletons too,
-     *                                  or just reset without re-instantiating (handy to set to FALSE if you're not
-     *                                  sure if you CAN currently reinstantiate the singletons at the moment)
-     * @param bool    $reset_models     Defaults to true.  When false, then the models are not reset.  This is so
-     *                                  client
-     *                                  code instead can just change the model context to a different blog id if
-     *                                  necessary
-     * @return EE_Registry
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public static function reset(bool $hard = false, bool $reinstantiate = true, bool $reset_models = true): EE_Registry
-    {
-        $instance            = self::instance();
-        $instance->_cache_on = true;
-        // reset some "special" classes
-        EEH_Activation::reset();
-        $hard = apply_filters('FHEE__EE_Registry__reset__hard', $hard);
-        $instance->CFG = EE_Config::reset($hard, $reinstantiate);
-        $instance->CART = null;
-        $instance->MRM = null;
-        // messages reset
-        EED_Messages::reset();
-        // handle of objects cached on LIB
-        foreach (['LIB', 'modules'] as $cache) {
-            foreach ($instance->{$cache} as $class_name => $class) {
-                if (self::_reset_and_unset_object($class, $reset_models)) {
-                    unset($instance->{$cache}->{$class_name});
-                }
-            }
-        }
-        return $instance;
-    }
-
-
-    /**
-     * if passed object implements ResettableInterface, then call it's reset() method
-     * if passed object implements InterminableInterface, then return false,
-     * to indicate that it should NOT be cleared from the Registry cache
-     *
-     * @param      $object
-     * @param bool $reset_models
-     * @return bool returns true if cached object should be unset
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    private static function _reset_and_unset_object($object, bool $reset_models): bool
-    {
-        if (! is_object($object)) {
-            // don't unset anything that's not an object
-            return false;
-        }
-        if ($object instanceof EED_Module) {
-            $object::reset();
-            // don't unset modules
-            return false;
-        }
-        if ($object instanceof ResettableInterface) {
-            if ($object instanceof EEM_Base) {
-                if ($reset_models) {
-                    $object->reset();
-                    return true;
-                }
-                return false;
-            }
-            $object->reset();
-            return true;
-        }
-        if (! $object instanceof InterminableInterface) {
-            return true;
-        }
-        return false;
-    }
-
-
-    /**
-     * Gets all the custom post type models defined
-     *
-     * @return array keys are model "short names" (Eg "Event") and keys are classnames (eg "EEM_Event")
-     */
-    public function cpt_models(): array
-    {
-        $cpt_models = [];
-        foreach ($this->non_abstract_db_models as $short_name => $classname) {
-            if (is_subclass_of($classname, 'EEM_CPT_Base')) {
-                $cpt_models[ $short_name ] = $classname;
-            }
-        }
-        return $cpt_models;
-    }
-
-
-    /**
-     * @return EE_Config
-     */
-    public static function CFG(): EE_Config
-    {
-        return self::instance()->CFG;
-    }
-
-
-    /**
-     * @param string $class_name
-     * @return ReflectionClass
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @deprecated 4.9.62.p
-     */
-    public function get_ReflectionClass(string $class_name): ReflectionClass
-    {
-        return $this->mirror->getReflectionClass($class_name);
-    }
-
-    private function parameterIsPrimitive(?string $param_class): bool
-    {
-        return in_array(
-            $param_class,
-            [
-                'array',
-                'bool',
-                'float',
-                'int',
-                'string',
-            ]
-        );
-    }
+	private static ?EE_Registry $_instance = null;
+
+	protected EE_Dependency_Map $_dependency_map;
+
+	private Mirror $mirror;
+
+	private ClassInterfaceCache $class_cache;
+
+	private ObjectIdentifier $object_identifier;
+
+	protected array $_class_abbreviations = [];
+
+	public ?CommandBusInterface $BUS = null;
+
+	public ?EE_Cart $CART = null;
+
+	public ?EE_Config $CFG = null;
+
+	public ?EE_Network_Config $NET_CFG = null;
+
+	/**
+	 * RegistryContainer for storing library classes in
+	 *
+	 * @var RegistryContainer|null $LIB
+	 */
+	public ?RegistryContainer $LIB = null;
+
+	/**
+	 * @var EE_Request_Handler|null $REQ
+	 * @deprecated 4.10.14.p
+	 */
+	public ?EE_Request_Handler $REQ = null;
+
+	public ?EE_Session $SSN = null;
+
+	/**
+	 * @since 4.5.0
+	 * @var EE_Capabilities|null $CAP
+	 */
+	public ?EE_Capabilities$CAP = null;
+
+	/**
+	 * @since 4.9.0
+	 * @var EE_Message_Resource_Manager|null $MRM
+	 */
+	public ?EE_Message_Resource_Manager $MRM = null;
+
+	public ?Registry $AssetsRegistry = null;
+
+	/**
+	 * RegistryContainer for holding addons which have registered themselves to work with EE core
+	 *
+	 * @var RegistryContainer|EE_Addon[] $addons
+	 */
+	public $addons = [];
+
+	/**
+	 * keys are 'short names' (eg Event), values are class names (eg 'EEM_Event')
+	 *
+	 * @var EEM_Base[] $models
+	 */
+	public array $models = [];
+
+	/**
+	 * @var RegistryContainer|EED_Module[] $modules
+	 */
+	public $modules = [];
+
+	/**
+	 * @var RegistryContainer|EES_Shortcode[] $shortcodes
+	 */
+	public $shortcodes = [];
+
+	/**
+	 * @var RegistryContainer|WP_Widget[] $widgets
+	 */
+	public $widgets = [];
+
+	/**
+	 * this is an array of all implemented model names (i.e. not the parent abstract models, or models
+	 * which don't actually fetch items from the DB in the normal way (ie, are not children of EEM_Base)).
+	 * Keys are model "short names" (eg "Event") as used in model relations, and values are
+	 * classnames (eg "EEM_Event")
+	 *
+	 * @var array $non_abstract_db_models
+	 */
+	public array $non_abstract_db_models = [];
+
+	/**
+	 * internationalization for JS strings
+	 *    usage:   EE_Registry::i18n_js_strings['string_key'] = esc_html__( 'string to translate.', 'event_espresso' );
+	 *    in js file:  var translatedString = eei18n.string_key;
+	 *
+	 * @var array $i18n_js_strings
+	 */
+	public static array $i18n_js_strings = [];
+
+	/**
+	 * $main_file - path to espresso.php
+	 *
+	 * @var string $main_file
+	 */
+	public string $main_file = '';
+
+	/**
+	 * boolean flag to indicate whether to load/save dependencies from/to the cache
+	 *
+	 * @var bool $_cache_on
+	 */
+	protected bool $_cache_on = true;
+
+
+	/**
+	 * @singleton method used to instantiate class object
+	 * @param EE_Dependency_Map|null   $dependency_map
+	 * @param Mirror|null              $mirror
+	 * @param ClassInterfaceCache|null $class_cache
+	 * @param ObjectIdentifier|null    $object_identifier
+	 * @return EE_Registry instance
+	 */
+	public static function instance(
+		EE_Dependency_Map $dependency_map = null,
+		Mirror $mirror = null,
+		ClassInterfaceCache $class_cache = null,
+		ObjectIdentifier $object_identifier = null
+	): EE_Registry {
+		// check if class object is instantiated
+		if (
+			! self::$_instance instanceof EE_Registry
+			&& $dependency_map instanceof EE_Dependency_Map
+			&& $mirror instanceof Mirror
+			&& $class_cache instanceof ClassInterfaceCache
+			&& $object_identifier instanceof ObjectIdentifier
+		) {
+			self::$_instance = new self(
+				$dependency_map,
+				$mirror,
+				$class_cache,
+				$object_identifier
+			);
+		}
+		return self::$_instance;
+	}
+
+
+	/**
+	 * protected constructor to prevent direct creation
+	 *
+	 * @Constructor
+	 * @param EE_Dependency_Map   $dependency_map
+	 * @param Mirror              $mirror
+	 * @param ClassInterfaceCache $class_cache
+	 * @param ObjectIdentifier    $object_identifier
+	 */
+	protected function __construct(
+		EE_Dependency_Map $dependency_map,
+		Mirror $mirror,
+		ClassInterfaceCache $class_cache,
+		ObjectIdentifier $object_identifier
+	) {
+		$this->_dependency_map   = $dependency_map;
+		$this->mirror            = $mirror;
+		$this->class_cache       = $class_cache;
+		$this->object_identifier = $object_identifier;
+
+		$this->LIB        = new RegistryContainer();
+		$this->addons     = new RegistryContainer();
+		$this->modules    = new RegistryContainer();
+		$this->shortcodes = new RegistryContainer();
+		$this->widgets    = new RegistryContainer();
+		add_action('EE_Load_Espresso_Core__handle_request__initialize_core_loading', [$this, 'initialize']);
+	}
+
+
+	/**
+	 * initialize
+	 *
+	 * @throws OutOfBoundsException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function initialize()
+	{
+		$this->_class_abbreviations = apply_filters(
+			'FHEE__EE_Registry____construct___class_abbreviations',
+			[
+				'EE_Config'                                       => 'CFG',
+				'EE_Session'                                      => 'SSN',
+				'EE_Capabilities'                                 => 'CAP',
+				'EE_Cart'                                         => 'CART',
+				'EE_Network_Config'                               => 'NET_CFG',
+				'EE_Request_Handler'                              => 'REQ',
+				'EE_Message_Resource_Manager'                     => 'MRM',
+				'EventEspresso\core\services\commands\CommandBus' => 'BUS',
+				'EventEspresso\core\services\assets\Registry'     => 'AssetsRegistry',
+			]
+		);
+		$this->load_core('Base', [], true);
+		// add our request and response objects to the cache
+		$request_loader = $this->_dependency_map->class_loader(
+			'EventEspresso\core\services\request\Request'
+		);
+		$this->_set_cached_class(
+			$request_loader(),
+			'EventEspresso\core\services\request\Request'
+		);
+		$response_loader = $this->_dependency_map->class_loader(
+			'EventEspresso\core\services\request\Response'
+		);
+		$this->_set_cached_class(
+			$response_loader(),
+			'EventEspresso\core\services\request\Response'
+		);
+		add_action('AHEE__EE_System__set_hooks_for_core', [$this, 'init']);
+	}
+
+
+	/**
+	 * @return void
+	 */
+	public function init()
+	{
+		// Get current page protocol
+		$protocol = is_ssl() ? 'https://' : 'http://';
+		// Output admin-ajax.php URL with same protocol as current page
+		self::$i18n_js_strings['ajax_url'] = admin_url('admin-ajax.php', $protocol);
+		self::$i18n_js_strings['wp_debug'] = defined('WP_DEBUG') && WP_DEBUG;
+	}
+
+
+	/**
+	 * @return array
+	 */
+	public static function sanitize_i18n_js_strings(): array
+	{
+		array_walk(EE_Registry::$i18n_js_strings, function (&$value) {
+			if (is_scalar($value)) {
+				$value = html_entity_decode((string) $value, ENT_QUOTES, 'UTF-8');
+				// replace all escaped instances of \n with actual new lines
+				$value = str_replace("\\n", "\n", $value);
+			}
+		});
+		// sort the array by key in a case-insensitive manner
+		ksort(EE_Registry::$i18n_js_strings, SORT_NATURAL | SORT_FLAG_CASE);
+		return EE_Registry::$i18n_js_strings;
+	}
+
+
+	/**
+	 * localize_i18n_js_strings
+	 *
+	 * @return string
+	 */
+	public static function localize_i18n_js_strings(): string
+	{
+		$i18n_js_strings = wp_json_encode(EE_Registry::sanitize_i18n_js_strings());
+		return "/* <![CDATA[ */ var eei18n = $i18n_js_strings; /* ]]> */";
+	}
+
+
+	/**
+	 * @param mixed string | EED_Module $module
+	 * @throws OutOfBoundsException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function add_module($module)
+	{
+		if ($module instanceof EED_Module) {
+			$module_class = get_class($module);
+			$this->modules->add($module_class, $module);
+		} else {
+			if (! class_exists('EE_Module_Request_Router', false)) {
+				$this->load_core('Module_Request_Router');
+			}
+			EE_Module_Request_Router::module_factory($module);
+		}
+	}
+
+
+	/**
+	 * @param string $module_name
+	 * @return mixed EED_Module | NULL
+	 */
+	public function get_module(string $module_name = '')
+	{
+		return $this->modules->get($module_name);
+	}
+
+
+	/**
+	 * loads core classes - must be singletons
+	 *
+	 * @param string $class_name - simple class name ie: session
+	 * @param mixed  $arguments
+	 * @param bool   $load_only
+	 * @return bool|null|object
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 */
+	public function load_core(string $class_name, $arguments = [], bool $load_only = false)
+	{
+		$core_paths = (array) apply_filters(
+			'FHEE__EE_Registry__load_core__core_paths',
+			[
+				EE_CORE,
+				EE_ADMIN,
+				EE_CPTS,
+				EE_CORE . 'CPTs/',
+				EE_CORE . 'data_migration_scripts/',
+				EE_CORE . 'request_stack/',
+				EE_CORE . 'middleware/',
+			]
+		);
+		// retrieve instantiated class
+		return $this->_load(
+			$core_paths,
+			'EE_',
+			$class_name,
+			'core',
+			$arguments,
+			false,
+			true,
+			$load_only
+		);
+	}
+
+
+	/**
+	 * loads service classes
+	 *
+	 * @param string $class_name - simple class name ie: session
+	 * @param mixed  $arguments
+	 * @param bool   $load_only
+	 * @return bool|null|object
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @deprecated  4.10.33.p
+	 */
+	public function load_service(string $class_name, $arguments = [], bool $load_only = false)
+	{
+		$service_paths = (array) apply_filters(
+			'FHEE__EE_Registry__load_service__service_paths',
+			[
+				EE_CORE . 'services/',
+			]
+		);
+		// retrieve instantiated class
+		return $this->_load(
+			$service_paths,
+			'EE_',
+			$class_name,
+			'class',
+			$arguments,
+			false,
+			true,
+			$load_only
+		);
+	}
+
+
+	/**
+	 * loads data_migration_scripts
+	 *
+	 * @param string $class_name - class name for the DMS ie: EE_DMS_Core_4_2_0
+	 * @param mixed  $arguments
+	 * @return bool|null|object
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 */
+	public function load_dms(string $class_name, $arguments = [])
+	{
+		// retrieve instantiated class
+		return $this->_load(
+			EE_Data_Migration_Manager::instance()->get_data_migration_script_folders(),
+			'EE_DMS_',
+			$class_name,
+			'dms',
+			$arguments,
+			false,
+			false
+		);
+	}
+
+
+	/**
+	 * loads object creating classes - must be singletons
+	 *
+	 * @param string $class_name - simple class name ie: attendee
+	 * @param mixed  $arguments  - an array of arguments to pass to the class
+	 * @param bool   $from_db    - some classes are instantiated from the db and thus call a different method to
+	 *                           instantiate
+	 * @param bool   $cache      if you don't want the class to be stored in the internal cache (non-persistent) then
+	 *                           set this to FALSE (ie. when instantiating model objects from client in a loop)
+	 * @param bool   $load_only  whether or not to just load the file and NOT instantiate, or load AND instantiate
+	 *                           (default)
+	 * @return EE_Base_Class|object|bool|null
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 */
+	public function load_class(
+		string $class_name,
+		$arguments = [],
+		bool $from_db = false,
+		bool $cache = true,
+		bool $load_only = false
+	) {
+		$paths = (array) apply_filters(
+			'FHEE__EE_Registry__load_class__paths',
+			[
+				EE_CORE,
+				EE_CLASSES,
+				EE_BUSINESS,
+			]
+		);
+		// retrieve instantiated class
+		return $this->_load(
+			$paths,
+			'EE_',
+			$class_name,
+			'class',
+			$arguments,
+			$from_db,
+			$cache,
+			$load_only
+		);
+	}
+
+
+	/**
+	 * loads helper classes - must be singletons
+	 *
+	 * @param string $class_name - simple class name ie: price
+	 * @param mixed  $arguments
+	 * @param bool   $load_only
+	 * @return bool|null|object
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 */
+	public function load_helper(string $class_name, $arguments = [], bool $load_only = true)
+	{
+		// todo: add doing_it_wrong() in a few versions after all addons have had calls to this method removed
+		$helper_paths = (array) apply_filters('FHEE__EE_Registry__load_helper__helper_paths', [EE_HELPERS]);
+		// retrieve instantiated class
+		return $this->_load(
+			$helper_paths,
+			'EEH_',
+			$class_name,
+			'helper',
+			$arguments,
+			false,
+			true,
+			$load_only
+		);
+	}
+
+
+	/**
+	 * loads core classes - must be singletons
+	 *
+	 * @param string $class_name - simple class name ie: session
+	 * @param mixed  $arguments
+	 * @param bool   $load_only
+	 * @param bool   $cache      whether to cache the object or not.
+	 * @return bool|null|object
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 */
+	public function load_lib(string $class_name, $arguments = [], bool $load_only = false, bool $cache = true)
+	{
+		$paths = [
+			EE_LIBRARIES,
+			EE_LIBRARIES . 'messages/',
+			EE_LIBRARIES . 'shortcodes/',
+			EE_LIBRARIES . 'qtips/',
+			EE_LIBRARIES . 'payment_methods/',
+		];
+		// retrieve instantiated class
+		return $this->_load(
+			$paths,
+			'EE_',
+			$class_name,
+			'lib',
+			$arguments,
+			false,
+			$cache,
+			$load_only
+		);
+	}
+
+
+	/**
+	 * loads model classes - must be singletons
+	 *
+	 * @param string $class_name - simple class name ie: price
+	 * @param mixed  $arguments
+	 * @param bool   $load_only
+	 * @return EEM_Base|null
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 */
+	public function load_model(string $class_name, $arguments = [], bool $load_only = false): ?EEM_Base
+	{
+		// retrieve instantiated class
+		$model = $this->_load(
+			(array) apply_filters(
+				'FHEE__EE_Registry__load_model__paths',
+				[
+					EE_MODELS,
+					EE_CORE,
+				]
+			),
+			'EEM_',
+			$class_name,
+			'model',
+			$arguments,
+			false,
+			true,
+			$load_only
+		);
+		return $model instanceof EEM_Base ? $model : null;
+	}
+
+
+	/**
+	 * loads model classes - must be singletons
+	 *
+	 * @param string $class_name - simple class name ie: price
+	 * @param mixed  $arguments
+	 * @param bool   $load_only
+	 * @return bool|null|object
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @deprecated  4.10.33.p
+	 */
+	public function load_model_class(string $class_name, $arguments = [], bool $load_only = true)
+	{
+		$paths = [
+			EE_MODELS . 'fields/',
+			EE_MODELS . 'helpers/',
+			EE_MODELS . 'relations/',
+			EE_MODELS . 'strategies/',
+		];
+		// retrieve instantiated class
+		return $this->_load(
+			$paths,
+			'EE_',
+			$class_name,
+			'',
+			$arguments,
+			false,
+			true,
+			$load_only
+		);
+	}
+
+
+	/**
+	 * Determines if $model_name is the name of an actual EE model.
+	 *
+	 * @param string $model_name like Event, Attendee, Question_Group_Question, etc.
+	 * @return boolean
+	 */
+	public function is_model_name(string $model_name): bool
+	{
+		return isset($this->models[ $model_name ]);
+	}
+
+
+	/**
+	 * generic class loader
+	 *
+	 * @param string $path_to_file - directory path to file location, not including filename
+	 * @param string $file_name    - file name  ie:  my_file.php, including extension
+	 * @param string $type         - file type - core? class? helper? model?
+	 * @param mixed  $arguments
+	 * @param bool   $load_only
+	 * @return bool|null|object
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 */
+	public function load_file(
+		string $path_to_file,
+		string $file_name,
+		string $type = '',
+		$arguments = [],
+		bool $load_only = true
+	) {
+		// retrieve instantiated class
+		return $this->_load(
+			(array) $path_to_file,
+			'',
+			$file_name,
+			$type,
+			$arguments,
+			false,
+			true,
+			$load_only
+		);
+	}
+
+
+	/**
+	 * @param string $path_to_file - directory path to file location, not including filename
+	 * @param string $class_name   - full class name  ie:  My_Class
+	 * @param string $type         - file type - core? class? helper? model?
+	 * @param mixed  $arguments
+	 * @param bool   $load_only
+	 * @return bool|null|object
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @deprecated  4.10.33.p
+	 */
+	public function load_addon(
+		string $path_to_file,
+		string $class_name,
+		string $type = 'class',
+		$arguments = [],
+		bool $load_only = false
+	) {
+		// retrieve instantiated class
+		return $this->_load(
+			(array) $path_to_file,
+			'addon',
+			$class_name,
+			$type,
+			$arguments,
+			false,
+			true,
+			$load_only
+		);
+	}
+
+
+	/**
+	 * instantiates, caches, and automatically resolves dependencies
+	 * for classes that use a Fully Qualified Class Name.
+	 * if the class is not capable of being loaded using PSR-4 autoloading,
+	 * then you need to use one of the existing load_*() methods
+	 * which can resolve the classname and filepath from the passed arguments
+	 *
+	 * @param string      $class_name Fully Qualified Class Name
+	 * @param array       $arguments  an argument, or array of arguments to pass to the class upon instantiation
+	 * @param bool        $cache      whether to cache the instantiated object for reuse
+	 * @param bool        $from_db    some classes are instantiated from the db
+	 *                                and thus call a different method to instantiate
+	 * @param bool        $load_only  if true, will only load the file, but will NOT instantiate an object
+	 * @param bool|string $addon      if true, will cache the object in the EE_Registry->$addons array
+	 * @return bool|null|mixed     null = failure to load or instantiate class object.
+	 *                                object = class loaded and instantiated successfully.
+	 *                                bool = fail or success when $load_only is true
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 */
+	public function create(
+		string $class_name = '',
+		array $arguments = [],
+		bool $cache = false,
+		bool $from_db = false,
+		bool $load_only = false,
+		bool $addon = false
+	) {
+		$class_name   = ltrim($class_name, '\\');
+		$class_name   = $this->class_cache->getFqnForAlias($class_name);
+		$class_exists = $this->loadOrVerifyClassExists($class_name, $arguments);
+		// if a non-FQCN was passed, then
+		// verifyClassExists() might return an object
+		// or it could return null if the class just could not be found anywhere
+		if ($class_exists instanceof $class_name || $class_exists === null) {
+			// either way, return the results
+			return $class_exists;
+		}
+		$class_name = $class_exists;
+		// if we're only loading the class and it already exists, then let's just return true immediately
+		if ($load_only) {
+			return true;
+		}
+		$addon = $addon ? 'addon' : '';
+		// $this->_cache_on is toggled during the recursive loading that can occur with dependency injection
+		// $cache is controlled by individual calls to separate Registry loader methods like load_class()
+		// $load_only is also controlled by individual calls to separate Registry loader methods like load_file()
+		if ($this->_cache_on && $cache) {
+			// return object if it's already cached
+			$cached_class = $this->_get_cached_class($class_name, $addon, $arguments);
+			if ($cached_class !== null) {
+				return $cached_class;
+			}
+		}                                                           // obtain the loader method from the dependency map
+		$loader = $this->_dependency_map->class_loader($class_name);// instantiate the requested object
+		if ($loader instanceof Closure) {
+			$class_obj = $loader($arguments);
+		} else {
+			if ($loader && method_exists($this, $loader)) {
+				$class_obj = $this->{$loader}($class_name, $arguments);
+			} else {
+				$class_obj = $this->_create_object($class_name, $arguments, $addon, $from_db);
+			}
+		}
+		if (($this->_cache_on && $cache) || $this->get_class_abbreviation($class_name, '')) {
+			// save it for later... kinda like gum  { : $
+			$this->_set_cached_class(
+				$class_obj,
+				$class_name,
+				$addon,
+				$from_db,
+				$arguments
+			);
+		}
+		$this->_cache_on = true;
+		return $class_obj;
+	}
+
+
+	/**
+	 * Recursively checks that a class exists and potentially attempts to load classes with non-FQCNs
+	 *
+	 * @param string|mixed $class_name
+	 * @param array        $arguments
+	 * @param int          $attempt
+	 * @return mixed
+	 */
+	private function loadOrVerifyClassExists($class_name, array $arguments, int $attempt = 1)
+	{
+		if (is_object($class_name) || class_exists($class_name)) {
+			return $class_name;
+		}
+		switch ($attempt) {
+			case 1:
+				// if it's a FQCN then maybe the class is registered with a preceding \
+				$class_name = strpos($class_name, '\\') !== false
+					? '\\' . ltrim($class_name, '\\')
+					: $class_name;
+				break;
+			case 2:
+				//
+				$loader = $this->_dependency_map->class_loader($class_name);
+				if ($loader && method_exists($this, $loader)) {
+					return $this->{$loader}($class_name, $arguments);
+				}
+				break;
+			case 3:
+			default:
+				return null;
+		}
+		$attempt++;
+		return $this->loadOrVerifyClassExists($class_name, $arguments, $attempt);
+	}
+
+
+	/**
+	 * instantiates, caches, and injects dependencies for classes
+	 *
+	 * @param array  $file_paths         an array of paths to folders to look in
+	 * @param string $class_prefix       EE  or EEM or... ???
+	 * @param string $class_name         $class name
+	 * @param string $type               file type - core? class? helper? model?
+	 * @param mixed  $arguments          an argument or array of arguments to pass to the class upon instantiation
+	 * @param bool   $from_db            some classes are instantiated from the db
+	 *                                   and thus call a different method to instantiate
+	 * @param bool   $cache              whether to cache the instantiated object for reuse
+	 * @param bool   $load_only          if true, will only load the file, but will NOT instantiate an object
+	 * @return bool|null|object          null   = failure to load or instantiate class object.
+	 *                                   object = class loaded and instantiated successfully.
+	 *                                   bool   = fail or success when $load_only is true
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidArgumentException
+	 */
+	protected function _load(
+		array $file_paths = [],
+		string $class_prefix = 'EE_',
+		string $class_name = '',
+		string $type = 'class',
+		array $arguments = [],
+		bool $from_db = false,
+		bool $cache = true,
+		bool $load_only = false
+	) {
+		$class_name = ltrim($class_name, '\\');
+		// strip php file extension
+		$class_name = str_replace('.php', '', trim($class_name));
+		// does the class have a prefix ?
+		if (! empty($class_prefix) && $class_prefix !== 'addon') {
+			// make sure $class_prefix is uppercase
+			$class_prefix = strtoupper(trim($class_prefix));
+			// add class prefix ONCE!!!
+			$class_name = $class_prefix . str_replace($class_prefix, '', $class_name);
+		}
+		$class_name   = $this->class_cache->getFqnForAlias($class_name);
+		$class_exists = class_exists($class_name, false);
+		// if we're only loading the class and it already exists, then let's just return true immediately
+		if ($load_only && $class_exists) {
+			return true;
+		}
+		$arguments = is_array($arguments) ? $arguments : [$arguments];
+		// $this->_cache_on is toggled during the recursive loading that can occur with dependency injection
+		// $cache is controlled by individual calls to separate Registry loader methods like load_class()
+		// $load_only is also controlled by individual calls to separate Registry loader methods like load_file()
+		if ($this->_cache_on && $cache && ! $load_only) {
+			// return object if it's already cached
+			$cached_class = $this->_get_cached_class($class_name, $class_prefix, $arguments);
+			if ($cached_class !== null) {
+				return $cached_class;
+			}
+		}
+		// if the class doesn't already exist.. then we need to try and find the file and load it
+		if (! $class_exists) {
+			// get full path to file
+			$path = $this->_resolve_path($class_name, $type, $file_paths);
+			// load the file
+			$loaded = $this->_require_file($path, $class_name, $type, $file_paths);
+			// if we are only loading a file but NOT instantiating an object
+			// then return boolean for whether class was loaded or not
+			if ($load_only) {
+				return $loaded;
+			}
+			// if an object was expected but loading failed, then return nothing
+			if (! $loaded) {
+				return null;
+			}
+		}
+		// instantiate the requested object
+		$class_obj = $this->_create_object($class_name, $arguments, $type, $from_db);
+		if ($this->_cache_on && $cache) {
+			// save it for later... kinda like gum  { : $
+			$this->_set_cached_class(
+				$class_obj,
+				$class_name,
+				$class_prefix,
+				$from_db,
+				$arguments
+			);
+		}
+		$this->_cache_on = true;
+		return $class_obj;
+	}
+
+
+	/**
+	 * @param string $class_name
+	 * @param string $default have to specify something, but not anything that will conflict
+	 * @return mixed|string
+	 */
+	protected function get_class_abbreviation(string $class_name, string $default = 'FANCY_BATMAN_PANTS')
+	{
+		return $this->_class_abbreviations[ $class_name ] ?? $default;
+	}
+
+
+	/**
+	 * attempts to find a cached version of the requested class
+	 * by looking in the following places:
+	 *        $this->{$class_abbreviation}            ie:    $this->CART
+	 *        $this->{$class_name}                        ie:    $this->Some_Class
+	 *        $this->LIB->{$class_name}                ie:    $this->LIB->Some_Class
+	 *        $this->addon->{$class_name}    ie:    $this->addon->Some_Addon_Class
+	 *
+	 * @param string $class_name
+	 * @param string $class_prefix
+	 * @param array  $arguments
+	 * @return mixed
+	 */
+	protected function _get_cached_class(
+		string $class_name,
+		string $class_prefix = '',
+		array $arguments = []
+	) {
+		if ($class_name === 'EE_Registry') {
+			return $this;
+		}
+		$class_abbreviation = $this->get_class_abbreviation($class_name);
+		// check if class has already been loaded, and return it if it has been
+		if (isset($this->{$class_abbreviation})) {
+			return $this->{$class_abbreviation};
+		}
+		$class_name = str_replace('\\', '_', $class_name);
+		if (isset($this->{$class_name})) {
+			return $this->{$class_name};
+		}
+		if ($class_prefix === 'addon' && $this->addons->has($class_name)) {
+			return $this->addons->get($class_name);
+		}
+		$object_identifier = $this->object_identifier->getIdentifier($class_name, $arguments);
+		if ($this->LIB->has($object_identifier)) {
+			return $this->LIB->get($object_identifier);
+		}
+		foreach ($this->LIB as $key => $object) {
+			if (
+				// request does not contain new arguments and therefore no args identifier
+				! $this->object_identifier->hasArguments($object_identifier)
+				// but previously cached class with args was found
+				&& $this->object_identifier->fqcnMatchesObjectIdentifier($class_name, $key)
+			) {
+				return $object;
+			}
+		}
+		return null;
+	}
+
+
+	/**
+	 * removes a cached version of the requested class
+	 *
+	 * @param string  $class_name
+	 * @param boolean $addon
+	 * @param array   $arguments
+	 * @return boolean
+	 */
+	public function clear_cached_class(
+		string $class_name,
+		bool $addon = false,
+		array $arguments = []
+	): bool {
+		$class_abbreviation = $this->get_class_abbreviation($class_name);
+		// check if class has already been loaded, and return it if it has been
+		if (isset($this->{$class_abbreviation})) {
+			$this->{$class_abbreviation} = null;
+			return true;
+		}
+		$class_name = str_replace('\\', '_', $class_name);
+		if (isset($this->{$class_name})) {
+			$this->{$class_name} = null;
+			return true;
+		}
+		if ($addon && $this->addons->has($class_name)) {
+			$this->addons->remove($class_name);
+			return true;
+		}
+		$class_name = $this->object_identifier->getIdentifier($class_name, $arguments);
+		if ($this->LIB->has($class_name)) {
+			$this->LIB->remove($class_name);
+			return true;
+		}
+		return false;
+	}
+
+
+	/**
+	 * _set_cached_class
+	 * attempts to cache the instantiated class locally
+	 * in one of the following places, in the following order:
+	 *        $this->{class_abbreviation}   ie:    $this->CART
+	 *        $this->{$class_name}          ie:    $this->Some_Class
+	 *        $this->addon->{$$class_name}    ie:    $this->addon->Some_Addon_Class
+	 *        $this->LIB->{$class_name}     ie:    $this->LIB->Some_Class
+	 *
+	 * @param object $class_obj
+	 * @param string $class_name
+	 * @param string $class_prefix
+	 * @param bool   $from_db
+	 * @param array  $arguments
+	 * @return void
+	 */
+	protected function _set_cached_class(
+		$class_obj,
+		string $class_name,
+		string $class_prefix = '',
+		bool $from_db = false,
+		array $arguments = []
+	) {
+		if ($class_name === 'EE_Registry' || empty($class_obj)) {
+			return;
+		}
+		// return newly instantiated class
+		$class_abbreviation = $this->get_class_abbreviation($class_name, '');
+		if ($class_abbreviation) {
+			$this->{$class_abbreviation} = $class_obj;
+			return;
+		}
+		$class_name = str_replace('\\', '_', $class_name);
+		if (property_exists($this, $class_name)) {
+			$this->{$class_name} = $class_obj;
+			return;
+		}
+		if ($class_prefix === 'addon') {
+			$this->addons->add($class_name, $class_obj);
+			return;
+		}
+		if (! $from_db) {
+			$class_name = $this->object_identifier->getIdentifier($class_name, $arguments);
+			$this->LIB->add($class_name, $class_obj);
+		}
+	}
+
+
+	/**
+	 * attempts to find a full valid filepath for the requested class.
+	 * loops thru each of the base paths in the $file_paths array and appends : "{classname} . {file type} . php"
+	 * then returns that path if the target file has been found and is readable
+	 *
+	 * @param string $class_name
+	 * @param string $type
+	 * @param array  $file_paths
+	 * @return string | bool
+	 */
+	protected function _resolve_path(string $class_name, string $type = '', array $file_paths = [])
+	{
+		// make sure $file_paths is an array
+		$file_paths = is_array($file_paths)
+			? $file_paths
+			: [$file_paths];
+		// cycle thru paths
+		foreach ($file_paths as $key => $file_path) {
+			// convert all separators to proper /, if no filepath, then use EE_CLASSES
+			$file_path = $file_path
+				? str_replace(['/', '\\'], '/', $file_path)
+				: EE_CLASSES;
+			// prep file type
+			$type = ! empty($type)
+				? trim($type, '.') . '.'
+				: '';
+			// build full file path
+			$file_paths[ $key ] = rtrim($file_path, '/') . '/' . $class_name . '.' . $type . 'php';
+			// does the file exist and can be read ?
+			if (is_readable($file_paths[ $key ])) {
+				return $file_paths[ $key ];
+			}
+		}
+		return false;
+	}
+
+
+	/**
+	 * basically just performs a require_once()
+	 * but with some error handling
+	 *
+	 * @param string $path
+	 * @param string $class_name
+	 * @param string $type
+	 * @param array  $file_paths
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	protected function _require_file(string $path, string $class_name, string $type = '', array $file_paths = []): bool
+	{
+		$this->resolve_legacy_class_parent($class_name);
+		// don't give up! you gotta...
+		try {
+			// does the file exist and can it be read ?
+			if (! $path) {
+				// just in case the file has already been autoloaded,
+				// but discrepancies in the naming schema are preventing it from
+				// being loaded via one of the EE_Registry::load_*() methods,
+				// then let's try one last hail mary before throwing an exception
+				// and call class_exists() again, but with autoloading turned ON
+				if (class_exists($class_name)) {
+					return true;
+				}
+				// so sorry, can't find the file
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							'The %1$s file %2$s could not be located or is not readable due to file permissions. Please ensure that the following filepath(s) are correct: %3$s',
+							'event_espresso'
+						),
+						trim($type, '.'),
+						$class_name,
+						'<br />' . implode(',<br />', $file_paths)
+					)
+				);
+			}
+			// get the file
+			require_once($path);
+			// if the class isn't already declared somewhere
+			if (class_exists($class_name, false) === false) {
+				// so sorry, not a class
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							'The %s file %s does not appear to contain the %s Class.',
+							'event_espresso'
+						),
+						$type,
+						$path,
+						$class_name
+					)
+				);
+			}
+		} catch (EE_Error $e) {
+			$e->get_error();
+			return false;
+		}
+		return true;
+	}
+
+
+	/**
+	 * Some of our legacy classes that extended a parent class would simply use a require() statement
+	 * before their class declaration in order to ensure that the parent class was loaded.
+	 * This is not ideal, but it's nearly impossible to determine the parent class of a non-namespaced class,
+	 * without triggering a fatal error because the parent class has yet to be loaded and therefore doesn't exist.
+	 *
+	 * @param string $class_name
+	 */
+	protected function resolve_legacy_class_parent(string $class_name = '')
+	{
+		try {
+			$legacy_parent_class_map = [
+				'EE_Payment_Processor' => 'core/business/EE_Processor_Base.class.php',
+			];
+			if (isset($legacy_parent_class_map[ $class_name ])) {
+				require_once EE_PLUGIN_DIR_PATH . $legacy_parent_class_map[ $class_name ];
+			}
+		} catch (Exception $exception) {
+		}
+	}
+
+
+	/**
+	 * _create_object
+	 * Attempts to instantiate the requested class via any of the
+	 * commonly used instantiation methods employed throughout EE.
+	 * The priority for instantiation is as follows:
+	 *        - abstract classes or any class flagged as "load only" (no instantiation occurs)
+	 *        - model objects via their 'new_instance_from_db' method
+	 *        - model objects via their 'new_instance' method
+	 *        - "singleton" classes" via their 'instance' method
+	 *    - standard instantiable classes via their __constructor
+	 * Prior to instantiation, if the classname exists in the dependency_map,
+	 * then the constructor for the requested class will be examined to determine
+	 * if any dependencies exist, and if they can be injected.
+	 * If so, then those classes will be added to the array of arguments passed to the constructor
+	 *
+	 * @param string $class_name
+	 * @param array  $arguments
+	 * @param string $type
+	 * @param bool   $from_db
+	 * @return null|object|bool
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 */
+	protected function _create_object(
+		string $class_name,
+		array $arguments = [],
+		string $type = '',
+		bool $from_db = false
+	) {
+		// create reflection
+		$reflector = $this->mirror->getReflectionClass($class_name);
+		// make sure arguments are an array
+		$arguments = is_array($arguments)
+			? $arguments
+			: [$arguments];
+		// and if arguments array is numerically and sequentially indexed, then we want it to remain as is,
+		// else wrap it in an additional array so that it doesn't get split into multiple parameters
+		$arguments = $this->_array_is_numerically_and_sequentially_indexed($arguments)
+			? $arguments
+			: [$arguments];
+		// attempt to inject dependencies ?
+		if ($this->_dependency_map->has($class_name)) {
+			$arguments = $this->_resolve_dependencies($reflector, $class_name, $arguments);
+		}
+		// instantiate the class if possible
+		if ($reflector->isAbstract()) {
+			// nothing to instantiate, loading file was enough
+			// does not throw an exception so $instantiation_mode is unused
+			// $instantiation_mode = "1) no constructor abstract class";
+			return true;
+		}
+		if (
+			empty($arguments)
+			&& $this->mirror->getConstructorFromReflection($reflector) === null
+			&& $reflector->isInstantiable()
+		) {
+			// no constructor = static methods only... nothing to instantiate, loading file was enough
+			// $instantiation_mode = "2) no constructor but instantiable";
+			return $reflector->newInstance();
+		}
+		if ($from_db && method_exists($class_name, 'new_instance_from_db')) {
+			// $instantiation_mode = "3) new_instance_from_db()";
+			return call_user_func_array([$class_name, 'new_instance_from_db'], $arguments);
+		}
+		if (method_exists($class_name, 'new_instance')) {
+			// $instantiation_mode = "4) new_instance()";
+			return call_user_func_array([$class_name, 'new_instance'], $arguments);
+		}
+		if (method_exists($class_name, 'instance')) {
+			// $instantiation_mode = "5) instance()";
+			return call_user_func_array([$class_name, 'instance'], $arguments);
+		}
+		if ($reflector->isInstantiable()) {
+			$args_passed_count = count($arguments);
+			$args_required_count = count($this->mirror->getRequiredParameters($class_name));
+			if ($args_passed_count < $args_required_count) {
+				throw new RuntimeException(
+					sprintf(
+						__(
+							'Invalid arguments supplied for the %1$s class, %2$s were required but %3$s were passed.',
+							'event_espresso'
+						),
+						$class_name,
+						$args_required_count,
+						$args_passed_count
+					)
+				);
+			}
+			// $instantiation_mode = "6) constructor";
+			return $reflector->newInstanceArgs($arguments);
+		}
+		// heh ? something's not right !
+		throw new EE_Error(
+			sprintf(
+				esc_html__('The %s file %s could not be instantiated.', 'event_espresso'),
+				$type,
+				$class_name
+			)
+		);
+	}
+
+
+	/**
+	 * @see http://stackoverflow.com/questions/173400/how-to-check-if-php-array-is-associative-or-sequential
+	 * @param array $array
+	 * @return bool
+	 */
+	protected function _array_is_numerically_and_sequentially_indexed(array $array): bool
+	{
+		return empty($array) || array_keys($array) === range(0, count($array) - 1);
+	}
+
+
+	/**
+	 * _resolve_dependencies
+	 * examines the constructor for the requested class to determine
+	 * if any dependencies exist, and if they can be injected.
+	 * If so, then those classes will be added to the array of arguments passed to the constructor
+	 * PLZ NOTE: this is achieved by type hinting the constructor params
+	 * For example:
+	 *        if attempting to load a class "Foo" with the following constructor:
+	 *        __construct( Bar $bar_class, Fighter $grohl_class )
+	 *        then $bar_class and $grohl_class will be added to the $arguments array,
+	 *        but only IF they are NOT already present in the incoming arguments array,
+	 *        and the correct classes can be loaded
+	 *
+	 * @param ReflectionClass $reflector
+	 * @param string          $class_name
+	 * @param array           $arguments
+	 * @return array
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function _resolve_dependencies(
+		ReflectionClass $reflector,
+		string $class_name,
+		array $arguments = []
+	): array {
+		// let's examine the constructor
+		$constructor = $this->mirror->getConstructorFromReflection($reflector);
+		// whu? huh? nothing?
+		if (! $constructor) {
+			return $arguments;
+		}
+		// get constructor parameters
+		$params = $this->mirror->getParametersFromReflection($reflector);
+		// and the keys for the incoming arguments array so that we can compare existing arguments with what is expected
+		$argument_keys = array_keys($arguments);
+		// now loop thru all the constructors' expected parameters
+		foreach ($params as $index => $param) {
+			try {
+				// is this a dependency for a specific class ?
+				$param_class = $this->mirror->getParameterClassName($param, $class_name, $index);
+			} catch (ReflectionException $exception) {
+				// uh-oh... most likely a legacy class that has not been autoloaded
+				// let's try to derive the classname from what we have now
+				// and hope that the property var name is close to the class name
+				$param_class = $param->getName();
+				$param_class = str_replace('_', ' ', $param_class);
+				$param_class = ucwords($param_class);
+				$param_class = str_replace(' ', '_', $param_class);
+			}
+			// BUT WAIT !!! This class may be an alias for something else (or getting replaced at runtime)
+			$param_class = $this->class_cache->isAlias($param_class, $class_name)
+				? $this->class_cache->getFqnForAlias($param_class, $class_name)
+				: $param_class;
+			if (
+				// param is not even a class
+				($param_class === null || $this->parameterIsPrimitive($param_class))
+				// and something already exists in the incoming arguments for this param
+				&& array_key_exists($index, $argument_keys)
+				&& isset($arguments[ $argument_keys[ $index ] ])
+			) {
+				// so let's skip this argument and move on to the next
+				continue;
+			}
+			// parameter is type hinted as a class
+			if ($param_class !== null) {
+				// parameter exists as an incoming argument, AND it's the correct class
+				if (
+					array_key_exists($index, $argument_keys)
+					&& isset($arguments[ $argument_keys[ $index ] ])
+					&& $arguments[ $argument_keys[ $index ] ] instanceof $param_class
+				) {
+					// skip this argument and move on to the next
+					continue;
+				}
+				// parameter should be injected
+				if ($this->_dependency_map->has_dependency_for_class($class_name, $param_class)) {
+					$arguments = $this->_resolve_dependency(
+						$class_name,
+						$param_class,
+						$arguments,
+						$index
+					);
+				}
+			}
+			if (empty($arguments[ $index ])) {
+				$default_value = $this->mirror->getParameterDefaultValue(
+					$param,
+					$class_name,
+					$index
+				);
+				// if there's no default value, and the incoming argument is an array (albeit empty), then use that
+				$arguments[ $index ] = $default_value === null
+									   && isset($arguments[ $index ])
+									   && is_array($arguments[ $index ])
+					? $arguments[ $index ]
+					: $default_value;
+			}
+		}
+		return $arguments;
+	}
+
+
+	/**
+	 * @param string $class_name
+	 * @param string $param_class
+	 * @param array  $arguments
+	 * @param mixed  $index
+	 * @return array
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 */
+	protected function _resolve_dependency(string $class_name, string $param_class, array $arguments, $index): array
+	{
+		$dependency = null;
+		// should dependency be loaded from cache ?
+		$cache_on = $this->_dependency_map->loading_strategy_for_class_dependency(
+			$class_name,
+			$param_class
+		);
+		$cache_on = $cache_on !== EE_Dependency_Map::load_new_object;
+		// we might have a dependency...
+		// let's MAYBE try and find it in our cache if that's what's been requested
+		$cached_class = $cache_on
+			? $this->_get_cached_class($param_class)
+			: null;
+		// and grab it if it exists
+		if ($cached_class instanceof $param_class) {
+			$dependency = $cached_class;
+		} elseif ($param_class !== $class_name) {
+			// obtain the loader method from the dependency map
+			$loader = $this->_dependency_map->class_loader($param_class);
+			// is loader a custom closure ?
+			if ($loader instanceof Closure) {
+				$dependency = $loader($arguments);
+			} else {
+				// set the cache on property for the recursive loading call
+				$this->_cache_on = $cache_on;
+				// if not, then let's try and load it via the registry
+				if ($loader && method_exists($this, $loader)) {
+					$dependency = $this->{$loader}($param_class);
+				} else {
+					$dependency = LoaderFactory::getLoader()->load(
+						$param_class,
+						[],
+						$cache_on
+					);
+				}
+			}
+		}
+		// did we successfully find the correct dependency ?
+		if ($dependency instanceof $param_class) {
+			// then let's inject it into the incoming array of arguments at the correct location
+			$arguments[ $index ] = $dependency;
+		}
+		return $arguments;
+	}
+
+
+	/**
+	 * call any loader that's been registered in the EE_Dependency_Map::$_class_loaders array
+	 *
+	 * @param string $classname PLEASE NOTE: the class name needs to match what's registered
+	 *                          in the EE_Dependency_Map::$_class_loaders array,
+	 *                          including the class prefix, ie: "EE_", "EEM_", "EEH_", etc
+	 * @param array  $arguments
+	 * @return object
+	 */
+	public static function factory(string $classname, array $arguments = [])
+	{
+		$loader = self::instance()->_dependency_map->class_loader($classname);
+		if ($loader instanceof Closure) {
+			return $loader($arguments);
+		}
+		if (method_exists(self::instance(), $loader)) {
+			return self::instance()->{$loader}($classname, $arguments);
+		}
+		return null;
+	}
+
+
+	/**
+	 * Gets the addon by its class name
+	 *
+	 * @param string $class_name
+	 * @return EE_Addon
+	 */
+	public function getAddon(string $class_name): ?EE_Addon
+	{
+		$class_name = str_replace('\\', '_', $class_name);
+		return $this->addons->{$class_name} ?? null;
+	}
+
+
+	/**
+	 * removes the addon from the internal cache
+	 *
+	 * @param string $class_name
+	 * @return void
+	 */
+	public function removeAddon(string $class_name)
+	{
+		$class_name = str_replace('\\', '_', $class_name);
+		$this->addons->remove($class_name);
+	}
+
+
+	/**
+	 * Gets the addon by its name/slug (not classname. For that, just
+	 * use the get_addon() method above
+	 *
+	 * @param string $name
+	 * @return EE_Addon
+	 */
+	public function get_addon_by_name(string $name): ?EE_Addon
+	{
+		foreach ($this->addons as $addon) {
+			if ($addon->name() === $name) {
+				return $addon;
+			}
+		}
+		return null;
+	}
+
+
+	/**
+	 * Gets an array of all the registered addons, where the keys are their names.
+	 * (ie, what each returns for their name() function)
+	 * They're already available on EE_Registry::instance()->addons as properties,
+	 * where each property's name is the addon's classname,
+	 * So if you just want to get the addon by classname,
+	 * OR use the get_addon() method above.
+	 * PLEASE  NOTE:
+	 * addons with Fully Qualified Class Names
+	 * have had the namespace separators converted to underscores,
+	 * so a classname like Fully\Qualified\ClassName
+	 * would have been converted to Fully_Qualified_ClassName
+	 *
+	 * @return EE_Addon[] where the KEYS are the addon's name()
+	 */
+	public function get_addons_by_name(): array
+	{
+		$addons = [];
+		foreach ($this->addons as $addon) {
+			$addons[ $addon->name() ] = $addon;
+		}
+		return $addons;
+	}
+
+
+	/**
+	 * Resets the specified model's instance AND makes sure EE_Registry doesn't keep
+	 * a stale copy of it around
+	 *
+	 * @param string $model_name
+	 * @return EEM_Base
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function reset_model(string $model_name): ?EEM_Base
+	{
+		$model_class_name = strpos($model_name, 'EEM_') !== 0
+			? "EEM_$model_name"
+			: $model_name;
+		if (! $this->LIB->has($model_class_name)) {
+			return null;
+		}
+		$model = $this->LIB->get($model_class_name);
+		if (! $model instanceof EEM_Base) {
+			return null;
+		}
+		// get that model reset it and make sure we nuke the old reference to it
+		if ($model instanceof $model_class_name && is_callable([$model_class_name, 'reset'])) {
+			$this->LIB->remove($model_class_name);
+			$this->LIB->add($model_class_name, $model->reset());
+		} else {
+			throw new EE_Error(
+				sprintf(
+					esc_html__('Model %s does not have a method "reset"', 'event_espresso'),
+					$model_name
+				)
+			);
+		}
+		return $model;
+	}
+
+
+	/**
+	 * Resets the registry.
+	 * The criteria for what gets reset is based on what can be shared between sites on the same request when
+	 * switch_to_blog is used in a multisite install.  Here is a list of things that are NOT reset.
+	 * - $_dependency_map
+	 * - $_class_abbreviations
+	 * - $NET_CFG (EE_Network_Config): The config is shared network wide so no need to reset.
+	 * - $REQ:  Still on the same request so no need to change.
+	 * - $CAP: There is no site specific state in the EE_Capability class.
+	 * - $SSN: Although ideally, the session should not be shared between site switches, we can't reset it because only
+	 * one Session can be active in a single request.  Resetting could resolve in "headers already sent" errors.
+	 * - $addons:  In multisite, the state of the addons is something controlled via hooks etc in a normal request.  So
+	 *             for now, we won't reset the addons because it could break calls to an add-ons class/methods in the
+	 *             switch or on the restore.
+	 * - $modules
+	 * - $shortcodes
+	 * - $widgets
+	 *
+	 * @param boolean $hard             [deprecated]
+	 * @param boolean $reinstantiate    whether to create new instances of EE_Registry's singletons too,
+	 *                                  or just reset without re-instantiating (handy to set to FALSE if you're not
+	 *                                  sure if you CAN currently reinstantiate the singletons at the moment)
+	 * @param bool    $reset_models     Defaults to true.  When false, then the models are not reset.  This is so
+	 *                                  client
+	 *                                  code instead can just change the model context to a different blog id if
+	 *                                  necessary
+	 * @return EE_Registry
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public static function reset(bool $hard = false, bool $reinstantiate = true, bool $reset_models = true): EE_Registry
+	{
+		$instance            = self::instance();
+		$instance->_cache_on = true;
+		// reset some "special" classes
+		EEH_Activation::reset();
+		$hard = apply_filters('FHEE__EE_Registry__reset__hard', $hard);
+		$instance->CFG = EE_Config::reset($hard, $reinstantiate);
+		$instance->CART = null;
+		$instance->MRM = null;
+		// messages reset
+		EED_Messages::reset();
+		// handle of objects cached on LIB
+		foreach (['LIB', 'modules'] as $cache) {
+			foreach ($instance->{$cache} as $class_name => $class) {
+				if (self::_reset_and_unset_object($class, $reset_models)) {
+					unset($instance->{$cache}->{$class_name});
+				}
+			}
+		}
+		return $instance;
+	}
+
+
+	/**
+	 * if passed object implements ResettableInterface, then call it's reset() method
+	 * if passed object implements InterminableInterface, then return false,
+	 * to indicate that it should NOT be cleared from the Registry cache
+	 *
+	 * @param      $object
+	 * @param bool $reset_models
+	 * @return bool returns true if cached object should be unset
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	private static function _reset_and_unset_object($object, bool $reset_models): bool
+	{
+		if (! is_object($object)) {
+			// don't unset anything that's not an object
+			return false;
+		}
+		if ($object instanceof EED_Module) {
+			$object::reset();
+			// don't unset modules
+			return false;
+		}
+		if ($object instanceof ResettableInterface) {
+			if ($object instanceof EEM_Base) {
+				if ($reset_models) {
+					$object->reset();
+					return true;
+				}
+				return false;
+			}
+			$object->reset();
+			return true;
+		}
+		if (! $object instanceof InterminableInterface) {
+			return true;
+		}
+		return false;
+	}
+
+
+	/**
+	 * Gets all the custom post type models defined
+	 *
+	 * @return array keys are model "short names" (Eg "Event") and keys are classnames (eg "EEM_Event")
+	 */
+	public function cpt_models(): array
+	{
+		$cpt_models = [];
+		foreach ($this->non_abstract_db_models as $short_name => $classname) {
+			if (is_subclass_of($classname, 'EEM_CPT_Base')) {
+				$cpt_models[ $short_name ] = $classname;
+			}
+		}
+		return $cpt_models;
+	}
+
+
+	/**
+	 * @return EE_Config
+	 */
+	public static function CFG(): EE_Config
+	{
+		return self::instance()->CFG;
+	}
+
+
+	/**
+	 * @param string $class_name
+	 * @return ReflectionClass
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @deprecated 4.9.62.p
+	 */
+	public function get_ReflectionClass(string $class_name): ReflectionClass
+	{
+		return $this->mirror->getReflectionClass($class_name);
+	}
+
+	private function parameterIsPrimitive(?string $param_class): bool
+	{
+		return in_array(
+			$param_class,
+			[
+				'array',
+				'bool',
+				'float',
+				'int',
+				'string',
+			]
+		);
+	}
 }

core/EE_Payment_Processor.core.php

Indentation +409 added lines, -409 removed lines

@@ -20,413 +20,413 @@
  */
 class EE_Payment_Processor extends EE_Processor_Base implements ResettableInterface
 {
-    private static ?EE_Payment_Processor $_instance = null;
-
-    private IpnHandler $ipn_handler;
-
-    private PaymentProcessor $payment_processor;
-
-    private PostPaymentProcessor $post_payment_processor;
-
-    private RegistrationPayments $registration_payments;
-
-
-    /**
-     * @singleton method used to instantiate class object
-     * @param PaymentProcessor|null     $payment_processor
-     * @param PostPaymentProcessor|null $post_payment_processor
-     * @param RegistrationPayments|null $registration_payments
-     * @param IpnHandler|null           $ipn_handler
-     * @return EE_Payment_Processor instance
-     */
-    public static function instance(
-        ?PaymentProcessor $payment_processor = null,
-        ?PostPaymentProcessor $post_payment_processor = null,
-        ?RegistrationPayments $registration_payments = null,
-        ?IpnHandler $ipn_handler = null
-    ): EE_Payment_Processor {
-        // check if class object is instantiated
-        if (! EE_Payment_Processor::$_instance instanceof EE_Payment_Processor) {
-            EE_Payment_Processor::$_instance = new EE_Payment_Processor(
-                $payment_processor,
-                $post_payment_processor,
-                $registration_payments,
-                $ipn_handler
-            );
-        }
-        return EE_Payment_Processor::$_instance;
-    }
-
-
-    /**
-     * @return EE_Payment_Processor
-     */
-    public static function reset(): EE_Payment_Processor
-    {
-        EE_Payment_Processor::$_instance = null;
-        return EE_Payment_Processor::instance();
-    }
-
-
-    /**
-     * @param PaymentProcessor|null     $payment_processor
-     * @param PostPaymentProcessor|null $post_payment_processor
-     * @param RegistrationPayments|null $registration_payments
-     * @param IpnHandler|null           $ipn_handler
-     */
-    private function __construct(
-        ?PaymentProcessor $payment_processor,
-        ?PostPaymentProcessor $post_payment_processor,
-        ?RegistrationPayments $registration_payments,
-        ?IpnHandler $ipn_handler
-    ) {
-        $this->payment_processor      = $payment_processor instanceof PaymentProcessor
-            ? $payment_processor
-            : LoaderFactory::getShared(PaymentProcessor::class);
-        $this->post_payment_processor = $post_payment_processor instanceof PostPaymentProcessor
-            ? $post_payment_processor
-            : LoaderFactory::getShared(PostPaymentProcessor::class);
-        $this->registration_payments  = $registration_payments instanceof RegistrationPayments
-            ? $registration_payments
-            : LoaderFactory::getShared(RegistrationPayments::class);
-        $this->ipn_handler            = $ipn_handler instanceof IpnHandler
-            ? $ipn_handler
-            : LoaderFactory::getShared(IpnHandler::class);
-        do_action('AHEE__EE_Payment_Processor__construct');
-    }
-
-
-    /**
-     * Using the selected gateway, processes the payment for that transaction, and updates the transaction
-     * appropriately. Saves the payment that is generated
-     *
-     * @param EE_Payment_Method         $payment_method
-     * @param EE_Transaction            $transaction
-     * @param float|null                $amount       if only part of the transaction is to be paid for, how much.
-     *                                                Leave null if payment is for the full amount owing
-     * @param EE_Billing_Info_Form|null $billing_form (or probably null, if it's an offline or offsite payment method).
-     *                                                Receive_form_submission() should have
-     *                                                already been called on the billing form
-     *                                                (ie, its inputs should have their normalized values set).
-     * @param string|null               $return_url   string used mostly by offsite gateways to specify
-     *                                                where to go AFTER the offsite gateway
-     * @param string                    $method       like 'CART', indicates who the client who called this was
-     * @param bool                      $by_admin     TRUE if payment is being attempted from the admin
-     * @param bool                      $update_txn   whether to call
-     *                                                EE_Transaction_Processor::update_transaction_and_registrations_after_checkout_or_payment()
-     * @param string                    $cancel_url   URL to return to if off-site payments are cancelled
-     * @return EE_Payment
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function process_payment(
-        EE_Payment_Method $payment_method,
-        EE_Transaction $transaction,
-        ?float $amount = null,
-        ?EE_Billing_Info_Form $billing_form = null,
-        ?string $return_url = null,
-        string $method = 'CART',
-        bool $by_admin = false,
-        bool $update_txn = true,
-        string $cancel_url = ''
-    ): ?EE_Payment {
-        return $this->payment_processor->processPayment(
-            $payment_method,
-            $transaction,
-            $billing_form,
-            (float) $amount,
-            $by_admin,
-            $update_txn,
-            (string) $return_url,
-            $cancel_url,
-            $method
-        );
-    }
-
-
-    /**
-     * @param EE_Transaction|int $transaction
-     * @param EE_Payment_Method  $payment_method
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_ipn_url_for_payment_method($transaction, $payment_method): string
-    {
-        /** @type EE_Transaction $transaction */
-        $transaction = EEM_Transaction::instance()->ensure_is_obj($transaction);
-        return $this->ipn_handler->getIpnUrlForPaymentMethod($transaction, $payment_method);
-    }
-
-
-    /**
-     * Process the IPN. Firstly, we'll hope we put the standard args into the IPN URL so
-     * we can easily find what registration the IPN is for and what payment method.
-     * However, if not, we'll give all payment methods a chance to claim it and process it.
-     * If a payment is found for the IPN info, it is saved.
-     *
-     * @param array              $_req_data            form post data
-     * @param EE_Transaction|int $transaction          optional (or a transactions id)
-     * @param EE_Payment_Method  $payment_method       (or a slug or id of one)
-     * @param boolean            $update_txn           whether to call
-     *                                                 EE_Transaction_Processor::update_transaction_and_registrations_after_checkout_or_payment()
-     * @param bool               $separate_IPN_request whether the IPN uses a separate request (true, like PayPal)
-     *                                                 or is processed manually (false, like Authorize.net)
-     * @return EE_Payment
-     * @throws EE_Error
-     * @throws Exception
-     * @throws ReflectionException
-     */
-    public function process_ipn(
-        $_req_data,
-        $transaction = null,
-        $payment_method = null,
-        $update_txn = true,
-        $separate_IPN_request = true
-    ) {
-        return $this->ipn_handler->processIPN(
-            (array) $_req_data,
-            $transaction,
-            $payment_method,
-            $update_txn,
-            $separate_IPN_request
-        );
-    }
-
-
-    /**
-     * Processes a direct refund request, saves the payment, and updates the transaction appropriately.
-     *
-     * @param EE_Payment_Method|null $payment_method
-     * @param EE_Payment             $payment_to_refund
-     * @param array                  $refund_info
-     * @return EE_Payment
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function process_refund(
-        ?EE_Payment_Method $payment_method,
-        EE_Payment $payment_to_refund,
-        array $refund_info = []
-    ): EE_Payment {
-        return $this->payment_processor->processRefund($payment_method, $payment_to_refund, $refund_info);
-    }
-
-
-    /**
-     * This should be called each time there may have been an update to a
-     * payment on a transaction (ie, we asked for a payment to process a
-     * payment for a transaction, or we told a payment method about an IPN, or
-     * we told a payment method to
-     * "finalize_payment_for" (a transaction), or we told a payment method to
-     * process a refund. This should handle firing the correct hooks to
-     * indicate
-     * what exactly happened and updating the transaction appropriately). This
-     * could be integrated directly into EE_Transaction upon save, but we want
-     * this logic to be separate from 'normal' plain-jane saving and updating
-     * of transactions and payments, and to be tied to payment processing.
-     * Note: this method DOES NOT save the payment passed into it. It is the responsibility
-     * of previous code to decide whether to save (because the payment passed into
-     * this method might be a temporary, never-to-be-saved payment from an offline gateway,
-     * in which case we only want that payment object for some temporary usage during this request,
-     * but we don't want it to be saved).
-     *
-     * @param EE_Transaction|int $transaction
-     * @param EE_Payment         $payment
-     * @param bool               $update_txn whether to call
-     *                                       EE_Transaction_Processor::update_transaction_and_registrations_after_checkout_or_payment()
-     *                                       (you can save 1 DB query if you know you're going to save it later
-     *                                       instead)
-     * @param bool               $IPN        if processing IPNs or other similar payment related activities that occur
-     *                                       in alternate requests than the main one that is processing the TXN,
-     *                                       then set this to true to check whether the TXN is locked before updating
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function update_txn_based_on_payment($transaction, $payment, $update_txn = true, $IPN = false)
-    {
-        $this->payment_processor->updateTransactionBasedOnPayment(
-            $transaction,
-            $payment,
-            (bool) $update_txn,
-            (bool) $IPN
-        );
-    }
-
-
-    /**
-     * update registrations REG_paid field after successful payment and link registrations with payment
-     *
-     * @param EE_Transaction    $transaction
-     * @param EE_Payment        $payment
-     * @param EE_Registration[] $registrations
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function process_registration_payments(
-        EE_Transaction $transaction,
-        EE_Payment $payment,
-        array $registrations = []
-    ) {
-        $this->registration_payments->processRegistrationPayments($transaction, $payment, $registrations);
-    }
-
-
-    /**
-     * update registration REG_paid field after successful payment and link registration with payment
-     *
-     * @param EE_Registration  $registration
-     * @param EE_Payment       $payment
-     * @param float|int|string $available_payment_amount
-     * @return float
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function process_registration_payment(
-        EE_Registration $registration,
-        EE_Payment $payment,
-        $available_payment_amount = 0.00
-    ) {
-        return $this->registration_payments->processRegistrationPayment(
-            $registration,
-            $payment,
-            (float) $available_payment_amount
-        );
-    }
-
-
-    /**
-     * update registration REG_paid field after refund and link registration with payment
-     *
-     * @param EE_Registration $registration
-     * @param EE_Payment      $payment
-     * @param float           $available_refund_amount - IMPORTANT !!! SEND AVAILABLE REFUND AMOUNT AS A POSITIVE NUMBER
-     * @return float
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function process_registration_refund(
-        EE_Registration $registration,
-        EE_Payment $payment,
-        float $available_refund_amount = 0.00
-    ): float {
-        return $this->registration_payments->processRegistrationRefund(
-            $registration,
-            $payment,
-            $available_refund_amount
-        );
-    }
-
-
-    /**
-     * Force posts to PayPal to use TLS v1.2. See:
-     * https://core.trac.wordpress.org/ticket/36320
-     * https://core.trac.wordpress.org/ticket/34924#comment:15
-     * https://www.paypal-knowledge.com/infocenter/index?page=content&widgetview=true&id=FAQ1914&viewlocale=en_US
-     * This will affect PayPal standard, pro, express, and Payflow.
-     *
-     * @param $handle
-     * @param $r
-     * @param $url
-     */
-    public static function _curl_requests_to_paypal_use_tls($handle, $r, $url)
-    {
-        if (strpos($url, 'https://') !== false && strpos($url, '.paypal.com') !== false) {
-            // Use the value of the constant CURL_SSLVERSION_TLSv1 = 1
-            // instead of the constant because it might not be defined
-            curl_setopt($handle, CURLOPT_SSLVERSION, 6);
-        }
-    }
-
-
-    /**
-     * Process payments and transaction after payment process completed.
-     * ultimately this will send the TXN and payment details off so that notifications can be sent out.
-     * if this request happens to be processing an IPN,
-     * then we will also set the Payment Options Reg Step to completed,
-     * and attempt to completely finalize the TXN if all the other Reg Steps are completed as well.
-     *
-     * @param EE_Transaction $transaction
-     * @param EE_Payment     $payment
-     * @param bool           $IPN
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @depecated 5.0.22.p
-     */
-    protected function _post_payment_processing(EE_Transaction $transaction, EE_Payment $payment, $IPN = false)
-    {
-        $this->post_payment_processor->updateTransactionAndPayment($transaction, $payment, (bool) $IPN);
-    }
-
-
-    /**
-     * update registration REG_paid field after successful payment and link registration with payment
-     *
-     * @param EE_Registration $registration
-     * @param EE_Payment      $payment
-     * @param float           $payment_amount
-     * @return void
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @depecated 5.0.22.p
-     */
-    protected function _apply_registration_payment(
-        EE_Registration $registration,
-        EE_Payment $payment,
-        $payment_amount = 0.00
-    ) {
-        // find any existing reg payment records for this registration and payment
-        $existing_reg_payment = EEM_Registration_Payment::instance()->get_one(
-            [['REG_ID' => $registration->ID(), 'PAY_ID' => $payment->ID()]]
-        );
-        // if existing registration payment exists
-        if ($existing_reg_payment instanceof EE_Registration_Payment) {
-            // then update that record
-            $existing_reg_payment->set_amount($payment_amount);
-            $existing_reg_payment->save();
-        } else {
-            // or add new relation between registration and payment and set amount
-            $registration->_add_relation_to(
-                $payment,
-                'Payment',
-                ['RPY_amount' => $payment_amount]
-            );
-            // make it stick
-            $registration->save();
-        }
-    }
-
-
-    /**
-     * Removes any non-printable illegal characters from the input,
-     * which might cause a raucous when trying to insert into the database
-     *
-     * @param array $request_data
-     * @return array
-     * @depecated 5.0.22.p
-     */
-    protected function _remove_unusable_characters_from_array(array $request_data)
-    {
-        $return_data = [];
-        foreach ($request_data as $key => $value) {
-            $return_data[ $this->_remove_unusable_characters($key) ] = $this->_remove_unusable_characters(
-                $value
-            );
-        }
-        return $return_data;
-    }
-
-
-    /**
-     * Removes any non-printable illegal characters from the input,
-     * which might cause a raucous when trying to insert into the database
-     *
-     * @param string $request_data
-     * @return string
-     * @depecated 5.0.22.p
-     */
-    protected function _remove_unusable_characters($request_data)
-    {
-        return preg_replace('/[^[:print:]]/', '', $request_data);
-    }
+	private static ?EE_Payment_Processor $_instance = null;
+
+	private IpnHandler $ipn_handler;
+
+	private PaymentProcessor $payment_processor;
+
+	private PostPaymentProcessor $post_payment_processor;
+
+	private RegistrationPayments $registration_payments;
+
+
+	/**
+	 * @singleton method used to instantiate class object
+	 * @param PaymentProcessor|null     $payment_processor
+	 * @param PostPaymentProcessor|null $post_payment_processor
+	 * @param RegistrationPayments|null $registration_payments
+	 * @param IpnHandler|null           $ipn_handler
+	 * @return EE_Payment_Processor instance
+	 */
+	public static function instance(
+		?PaymentProcessor $payment_processor = null,
+		?PostPaymentProcessor $post_payment_processor = null,
+		?RegistrationPayments $registration_payments = null,
+		?IpnHandler $ipn_handler = null
+	): EE_Payment_Processor {
+		// check if class object is instantiated
+		if (! EE_Payment_Processor::$_instance instanceof EE_Payment_Processor) {
+			EE_Payment_Processor::$_instance = new EE_Payment_Processor(
+				$payment_processor,
+				$post_payment_processor,
+				$registration_payments,
+				$ipn_handler
+			);
+		}
+		return EE_Payment_Processor::$_instance;
+	}
+
+
+	/**
+	 * @return EE_Payment_Processor
+	 */
+	public static function reset(): EE_Payment_Processor
+	{
+		EE_Payment_Processor::$_instance = null;
+		return EE_Payment_Processor::instance();
+	}
+
+
+	/**
+	 * @param PaymentProcessor|null     $payment_processor
+	 * @param PostPaymentProcessor|null $post_payment_processor
+	 * @param RegistrationPayments|null $registration_payments
+	 * @param IpnHandler|null           $ipn_handler
+	 */
+	private function __construct(
+		?PaymentProcessor $payment_processor,
+		?PostPaymentProcessor $post_payment_processor,
+		?RegistrationPayments $registration_payments,
+		?IpnHandler $ipn_handler
+	) {
+		$this->payment_processor      = $payment_processor instanceof PaymentProcessor
+			? $payment_processor
+			: LoaderFactory::getShared(PaymentProcessor::class);
+		$this->post_payment_processor = $post_payment_processor instanceof PostPaymentProcessor
+			? $post_payment_processor
+			: LoaderFactory::getShared(PostPaymentProcessor::class);
+		$this->registration_payments  = $registration_payments instanceof RegistrationPayments
+			? $registration_payments
+			: LoaderFactory::getShared(RegistrationPayments::class);
+		$this->ipn_handler            = $ipn_handler instanceof IpnHandler
+			? $ipn_handler
+			: LoaderFactory::getShared(IpnHandler::class);
+		do_action('AHEE__EE_Payment_Processor__construct');
+	}
+
+
+	/**
+	 * Using the selected gateway, processes the payment for that transaction, and updates the transaction
+	 * appropriately. Saves the payment that is generated
+	 *
+	 * @param EE_Payment_Method         $payment_method
+	 * @param EE_Transaction            $transaction
+	 * @param float|null                $amount       if only part of the transaction is to be paid for, how much.
+	 *                                                Leave null if payment is for the full amount owing
+	 * @param EE_Billing_Info_Form|null $billing_form (or probably null, if it's an offline or offsite payment method).
+	 *                                                Receive_form_submission() should have
+	 *                                                already been called on the billing form
+	 *                                                (ie, its inputs should have their normalized values set).
+	 * @param string|null               $return_url   string used mostly by offsite gateways to specify
+	 *                                                where to go AFTER the offsite gateway
+	 * @param string                    $method       like 'CART', indicates who the client who called this was
+	 * @param bool                      $by_admin     TRUE if payment is being attempted from the admin
+	 * @param bool                      $update_txn   whether to call
+	 *                                                EE_Transaction_Processor::update_transaction_and_registrations_after_checkout_or_payment()
+	 * @param string                    $cancel_url   URL to return to if off-site payments are cancelled
+	 * @return EE_Payment
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function process_payment(
+		EE_Payment_Method $payment_method,
+		EE_Transaction $transaction,
+		?float $amount = null,
+		?EE_Billing_Info_Form $billing_form = null,
+		?string $return_url = null,
+		string $method = 'CART',
+		bool $by_admin = false,
+		bool $update_txn = true,
+		string $cancel_url = ''
+	): ?EE_Payment {
+		return $this->payment_processor->processPayment(
+			$payment_method,
+			$transaction,
+			$billing_form,
+			(float) $amount,
+			$by_admin,
+			$update_txn,
+			(string) $return_url,
+			$cancel_url,
+			$method
+		);
+	}
+
+
+	/**
+	 * @param EE_Transaction|int $transaction
+	 * @param EE_Payment_Method  $payment_method
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_ipn_url_for_payment_method($transaction, $payment_method): string
+	{
+		/** @type EE_Transaction $transaction */
+		$transaction = EEM_Transaction::instance()->ensure_is_obj($transaction);
+		return $this->ipn_handler->getIpnUrlForPaymentMethod($transaction, $payment_method);
+	}
+
+
+	/**
+	 * Process the IPN. Firstly, we'll hope we put the standard args into the IPN URL so
+	 * we can easily find what registration the IPN is for and what payment method.
+	 * However, if not, we'll give all payment methods a chance to claim it and process it.
+	 * If a payment is found for the IPN info, it is saved.
+	 *
+	 * @param array              $_req_data            form post data
+	 * @param EE_Transaction|int $transaction          optional (or a transactions id)
+	 * @param EE_Payment_Method  $payment_method       (or a slug or id of one)
+	 * @param boolean            $update_txn           whether to call
+	 *                                                 EE_Transaction_Processor::update_transaction_and_registrations_after_checkout_or_payment()
+	 * @param bool               $separate_IPN_request whether the IPN uses a separate request (true, like PayPal)
+	 *                                                 or is processed manually (false, like Authorize.net)
+	 * @return EE_Payment
+	 * @throws EE_Error
+	 * @throws Exception
+	 * @throws ReflectionException
+	 */
+	public function process_ipn(
+		$_req_data,
+		$transaction = null,
+		$payment_method = null,
+		$update_txn = true,
+		$separate_IPN_request = true
+	) {
+		return $this->ipn_handler->processIPN(
+			(array) $_req_data,
+			$transaction,
+			$payment_method,
+			$update_txn,
+			$separate_IPN_request
+		);
+	}
+
+
+	/**
+	 * Processes a direct refund request, saves the payment, and updates the transaction appropriately.
+	 *
+	 * @param EE_Payment_Method|null $payment_method
+	 * @param EE_Payment             $payment_to_refund
+	 * @param array                  $refund_info
+	 * @return EE_Payment
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function process_refund(
+		?EE_Payment_Method $payment_method,
+		EE_Payment $payment_to_refund,
+		array $refund_info = []
+	): EE_Payment {
+		return $this->payment_processor->processRefund($payment_method, $payment_to_refund, $refund_info);
+	}
+
+
+	/**
+	 * This should be called each time there may have been an update to a
+	 * payment on a transaction (ie, we asked for a payment to process a
+	 * payment for a transaction, or we told a payment method about an IPN, or
+	 * we told a payment method to
+	 * "finalize_payment_for" (a transaction), or we told a payment method to
+	 * process a refund. This should handle firing the correct hooks to
+	 * indicate
+	 * what exactly happened and updating the transaction appropriately). This
+	 * could be integrated directly into EE_Transaction upon save, but we want
+	 * this logic to be separate from 'normal' plain-jane saving and updating
+	 * of transactions and payments, and to be tied to payment processing.
+	 * Note: this method DOES NOT save the payment passed into it. It is the responsibility
+	 * of previous code to decide whether to save (because the payment passed into
+	 * this method might be a temporary, never-to-be-saved payment from an offline gateway,
+	 * in which case we only want that payment object for some temporary usage during this request,
+	 * but we don't want it to be saved).
+	 *
+	 * @param EE_Transaction|int $transaction
+	 * @param EE_Payment         $payment
+	 * @param bool               $update_txn whether to call
+	 *                                       EE_Transaction_Processor::update_transaction_and_registrations_after_checkout_or_payment()
+	 *                                       (you can save 1 DB query if you know you're going to save it later
+	 *                                       instead)
+	 * @param bool               $IPN        if processing IPNs or other similar payment related activities that occur
+	 *                                       in alternate requests than the main one that is processing the TXN,
+	 *                                       then set this to true to check whether the TXN is locked before updating
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function update_txn_based_on_payment($transaction, $payment, $update_txn = true, $IPN = false)
+	{
+		$this->payment_processor->updateTransactionBasedOnPayment(
+			$transaction,
+			$payment,
+			(bool) $update_txn,
+			(bool) $IPN
+		);
+	}
+
+
+	/**
+	 * update registrations REG_paid field after successful payment and link registrations with payment
+	 *
+	 * @param EE_Transaction    $transaction
+	 * @param EE_Payment        $payment
+	 * @param EE_Registration[] $registrations
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function process_registration_payments(
+		EE_Transaction $transaction,
+		EE_Payment $payment,
+		array $registrations = []
+	) {
+		$this->registration_payments->processRegistrationPayments($transaction, $payment, $registrations);
+	}
+
+
+	/**
+	 * update registration REG_paid field after successful payment and link registration with payment
+	 *
+	 * @param EE_Registration  $registration
+	 * @param EE_Payment       $payment
+	 * @param float|int|string $available_payment_amount
+	 * @return float
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function process_registration_payment(
+		EE_Registration $registration,
+		EE_Payment $payment,
+		$available_payment_amount = 0.00
+	) {
+		return $this->registration_payments->processRegistrationPayment(
+			$registration,
+			$payment,
+			(float) $available_payment_amount
+		);
+	}
+
+
+	/**
+	 * update registration REG_paid field after refund and link registration with payment
+	 *
+	 * @param EE_Registration $registration
+	 * @param EE_Payment      $payment
+	 * @param float           $available_refund_amount - IMPORTANT !!! SEND AVAILABLE REFUND AMOUNT AS A POSITIVE NUMBER
+	 * @return float
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function process_registration_refund(
+		EE_Registration $registration,
+		EE_Payment $payment,
+		float $available_refund_amount = 0.00
+	): float {
+		return $this->registration_payments->processRegistrationRefund(
+			$registration,
+			$payment,
+			$available_refund_amount
+		);
+	}
+
+
+	/**
+	 * Force posts to PayPal to use TLS v1.2. See:
+	 * https://core.trac.wordpress.org/ticket/36320
+	 * https://core.trac.wordpress.org/ticket/34924#comment:15
+	 * https://www.paypal-knowledge.com/infocenter/index?page=content&widgetview=true&id=FAQ1914&viewlocale=en_US
+	 * This will affect PayPal standard, pro, express, and Payflow.
+	 *
+	 * @param $handle
+	 * @param $r
+	 * @param $url
+	 */
+	public static function _curl_requests_to_paypal_use_tls($handle, $r, $url)
+	{
+		if (strpos($url, 'https://') !== false && strpos($url, '.paypal.com') !== false) {
+			// Use the value of the constant CURL_SSLVERSION_TLSv1 = 1
+			// instead of the constant because it might not be defined
+			curl_setopt($handle, CURLOPT_SSLVERSION, 6);
+		}
+	}
+
+
+	/**
+	 * Process payments and transaction after payment process completed.
+	 * ultimately this will send the TXN and payment details off so that notifications can be sent out.
+	 * if this request happens to be processing an IPN,
+	 * then we will also set the Payment Options Reg Step to completed,
+	 * and attempt to completely finalize the TXN if all the other Reg Steps are completed as well.
+	 *
+	 * @param EE_Transaction $transaction
+	 * @param EE_Payment     $payment
+	 * @param bool           $IPN
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @depecated 5.0.22.p
+	 */
+	protected function _post_payment_processing(EE_Transaction $transaction, EE_Payment $payment, $IPN = false)
+	{
+		$this->post_payment_processor->updateTransactionAndPayment($transaction, $payment, (bool) $IPN);
+	}
+
+
+	/**
+	 * update registration REG_paid field after successful payment and link registration with payment
+	 *
+	 * @param EE_Registration $registration
+	 * @param EE_Payment      $payment
+	 * @param float           $payment_amount
+	 * @return void
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @depecated 5.0.22.p
+	 */
+	protected function _apply_registration_payment(
+		EE_Registration $registration,
+		EE_Payment $payment,
+		$payment_amount = 0.00
+	) {
+		// find any existing reg payment records for this registration and payment
+		$existing_reg_payment = EEM_Registration_Payment::instance()->get_one(
+			[['REG_ID' => $registration->ID(), 'PAY_ID' => $payment->ID()]]
+		);
+		// if existing registration payment exists
+		if ($existing_reg_payment instanceof EE_Registration_Payment) {
+			// then update that record
+			$existing_reg_payment->set_amount($payment_amount);
+			$existing_reg_payment->save();
+		} else {
+			// or add new relation between registration and payment and set amount
+			$registration->_add_relation_to(
+				$payment,
+				'Payment',
+				['RPY_amount' => $payment_amount]
+			);
+			// make it stick
+			$registration->save();
+		}
+	}
+
+
+	/**
+	 * Removes any non-printable illegal characters from the input,
+	 * which might cause a raucous when trying to insert into the database
+	 *
+	 * @param array $request_data
+	 * @return array
+	 * @depecated 5.0.22.p
+	 */
+	protected function _remove_unusable_characters_from_array(array $request_data)
+	{
+		$return_data = [];
+		foreach ($request_data as $key => $value) {
+			$return_data[ $this->_remove_unusable_characters($key) ] = $this->_remove_unusable_characters(
+				$value
+			);
+		}
+		return $return_data;
+	}
+
+
+	/**
+	 * Removes any non-printable illegal characters from the input,
+	 * which might cause a raucous when trying to insert into the database
+	 *
+	 * @param string $request_data
+	 * @return string
+	 * @depecated 5.0.22.p
+	 */
+	protected function _remove_unusable_characters($request_data)
+	{
+		return preg_replace('/[^[:print:]]/', '', $request_data);
+	}
 }

core/db_classes/EE_Event.class.php

Indentation +1634 added lines, -1634 removed lines

@@ -16,1641 +16,1641 @@
  */
 class EE_Event extends EE_CPT_Base implements EEI_Line_Item_Object, EEI_Admin_Links, EEI_Has_Icon, EEI_Event
 {
-    /**
-     * cached value for the the logical active status for the event
-     *
-     * @see get_active_status()
-     * @var string
-     */
-    protected $_active_status = '';
-
-    /**
-     * This is just used for caching the Primary Datetime for the Event on initial retrieval
-     *
-     * @var EE_Datetime
-     */
-    protected $_Primary_Datetime;
-
-    /**
-     * @var EventSpacesCalculator $available_spaces_calculator
-     */
-    protected $available_spaces_calculator;
-
-
-    /**
-     * @param array  $props_n_values          incoming values
-     * @param string $timezone                incoming timezone (if not set the timezone set for the website will be
-     *                                        used.)
-     * @param array  $date_formats            incoming date_formats in an array where the first value is the
-     *                                        date_format and the second value is the time format
-     * @return EE_Event
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public static function new_instance($props_n_values = [], $timezone = '', $date_formats = []): EE_Event
-    {
-        $has_object = parent::_check_for_object($props_n_values, __CLASS__, $timezone, $date_formats);
-        return $has_object ?: new self($props_n_values, false, $timezone, $date_formats);
-    }
-
-
-    /**
-     * @param array  $props_n_values  incoming values from the database
-     * @param string $timezone        incoming timezone as set by the model.  If not set the timezone for
-     *                                the website will be used.
-     * @return EE_Event
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public static function new_instance_from_db($props_n_values = [], $timezone = ''): EE_Event
-    {
-        return new self($props_n_values, true, $timezone);
-    }
-
-
-    /**
-     * @return EventSpacesCalculator
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function getAvailableSpacesCalculator(): EventSpacesCalculator
-    {
-        if (! $this->available_spaces_calculator instanceof EventSpacesCalculator) {
-            $this->available_spaces_calculator = new EventSpacesCalculator($this);
-        }
-        return $this->available_spaces_calculator;
-    }
-
-
-    /**
-     * Overrides parent set() method so that all calls to set( 'status', $status ) can be routed to internal methods
-     *
-     * @param string $field_name
-     * @param mixed  $field_value
-     * @param bool   $use_default
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set($field_name, $field_value, $use_default = false)
-    {
-        switch ($field_name) {
-            case 'status':
-                $this->set_status($field_value, $use_default);
-                break;
-            default:
-                parent::set($field_name, $field_value, $use_default);
-        }
-    }
-
-
-    /**
-     *    set_status
-     * Checks if event status is being changed to SOLD OUT
-     * and updates event meta data with previous event status
-     * so that we can revert things if/when the event is no longer sold out
-     *
-     * @param string $status
-     * @param bool   $use_default
-     * @return void
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_status($status = '', $use_default = false)
-    {
-        // if nothing is set, and we aren't explicitly wanting to reset the status, then just leave
-        if (empty($status) && ! $use_default) {
-            return;
-        }
-        // get current Event status
-        $old_status = $this->status();
-        // if status has changed
-        if ($old_status !== $status) {
-            // TO sold_out
-            if ($status === EEM_Event::sold_out) {
-                // save the previous event status so that we can revert if the event is no longer sold out
-                $this->add_post_meta('_previous_event_status', $old_status);
-                do_action('AHEE__EE_Event__set_status__to_sold_out', $this, $old_status, $status);
-                // OR FROM  sold_out
-            } elseif ($old_status === EEM_Event::sold_out) {
-                $this->delete_post_meta('_previous_event_status');
-                do_action('AHEE__EE_Event__set_status__from_sold_out', $this, $old_status, $status);
-            }
-            // clear out the active status so that it gets reset the next time it is requested
-            $this->_active_status = null;
-            // update status
-            parent::set('status', $status, $use_default);
-            do_action('AHEE__EE_Event__set_status__after_update', $this);
-            return;
-        }
-        // even though the old value matches the new value, it's still good to
-        // allow the parent set method to have a say
-        parent::set('status', $status, $use_default);
-    }
-
-
-    /**
-     * Gets all the datetimes for this event
-     *
-     * @param array|null $query_params
-     * @return EE_Base_Class[]|EE_Datetime[]
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     */
-    public function datetimes(?array $query_params = []): array
-    {
-        return $this->get_many_related('Datetime', $query_params);
-    }
-
-
-    /**
-     * Gets all the datetimes for this event that are currently ACTIVE,
-     * meaning the datetime has started and has not yet ended.
-     *
-     * @param int|null   $start_date   timestamp to use for event date start time, defaults to NOW unless set to 0
-     * @param array|null $query_params will recursively replace default values
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     */
-    public function activeDatetimes(?int $start_date, ?array $query_params = []): array
-    {
-        // if start date is null, then use current time
-        $start_date = $start_date ?? time();
-        $where      = [];
-        if ($start_date) {
-            $where['DTT_EVT_start'] = ['<', $start_date];
-            $where['DTT_EVT_end']   = ['>', time()];
-        }
-        $query_params = array_replace_recursive(
-            [
-                $where,
-                'order_by' => ['DTT_EVT_start' => 'ASC'],
-            ],
-            $query_params
-        );
-        return $this->get_many_related('Datetime', $query_params);
-    }
-
-
-    /**
-     * Gets all the datetimes for this event, ordered by DTT_EVT_start in ascending order
-     *
-     * @return EE_Base_Class[]|EE_Datetime[]
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function datetimes_in_chronological_order(): array
-    {
-        return $this->get_many_related('Datetime', ['order_by' => ['DTT_EVT_start' => 'ASC']]);
-    }
-
-
-    /**
-     * Gets all the datetimes for this event, ordered by the DTT_order on the datetime.
-     * @darren, we should probably UNSET timezone on the EEM_Datetime model
-     * after running our query, so that this timezone isn't set for EVERY query
-     * on EEM_Datetime for the rest of the request, no?
-     *
-     * @param bool     $show_expired whether or not to include expired events
-     * @param bool     $show_deleted whether or not to include deleted events
-     * @param int|null $limit
-     * @return EE_Datetime[]
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function datetimes_ordered(bool $show_expired = true, bool $show_deleted = false, ?int $limit = null): array
-    {
-        return EEM_Datetime::instance($this->_timezone)->get_datetimes_for_event_ordered_by_DTT_order(
-            $this->ID(),
-            $show_expired,
-            $show_deleted,
-            $limit
-        );
-    }
-
-
-    /**
-     * Returns one related datetime. Mostly only used by some legacy code.
-     *
-     * @return EE_Base_Class|EE_Datetime
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function first_datetime(): EE_Datetime
-    {
-        return $this->get_first_related('Datetime');
-    }
-
-
-    /**
-     * Returns the 'primary' datetime for the event
-     *
-     * @param bool $try_to_exclude_expired
-     * @param bool $try_to_exclude_deleted
-     * @return EE_Datetime|null
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function primary_datetime(
-        bool $try_to_exclude_expired = true,
-        bool $try_to_exclude_deleted = true
-    ): ?EE_Datetime {
-        if (! empty($this->_Primary_Datetime)) {
-            return $this->_Primary_Datetime;
-        }
-        $this->_Primary_Datetime = EEM_Datetime::instance($this->_timezone)->get_primary_datetime_for_event(
-            $this->ID(),
-            $try_to_exclude_expired,
-            $try_to_exclude_deleted
-        );
-        return $this->_Primary_Datetime;
-    }
-
-
-    /**
-     * Gets all the tickets available for purchase of this event
-     *
-     * @param array|null $query_params
-     * @return EE_Base_Class[]|EE_Ticket[]
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     */
-    public function tickets(?array $query_params = []): array
-    {
-        // first get all datetimes
-        $datetimes = $this->datetimes_ordered();
-        if (! $datetimes) {
-            return [];
-        }
-        $datetime_ids = [];
-        foreach ($datetimes as $datetime) {
-            $datetime_ids[] = $datetime->ID();
-        }
-        $where_params = ['Datetime.DTT_ID' => ['IN', $datetime_ids]];
-        // if incoming $query_params has where conditions let's merge but not override existing.
-        if (is_array($query_params) && isset($query_params[0])) {
-            $where_params = array_merge($query_params[0], $where_params);
-            unset($query_params[0]);
-        }
-        // now add $where_params to $query_params
-        $query_params[0] = $where_params;
-        return EEM_Ticket::instance()->get_all($query_params);
-    }
-
-
-    /**
-     * get all unexpired not-trashed tickets
-     *
-     * @return EE_Ticket[]
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function active_tickets(): array
-    {
-        return $this->tickets(
-            [
-                [
-                    'TKT_end_date' => ['>=', EEM_Ticket::instance()->current_time_for_query('TKT_end_date')],
-                    'TKT_deleted'  => false,
-                ],
-            ]
-        );
-    }
-
-
-    /**
-     * @return int
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function additional_limit(): int
-    {
-        return $this->get('EVT_additional_limit');
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function allow_overflow(): bool
-    {
-        return $this->get('EVT_allow_overflow');
-    }
-
-
-    /**
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function created(): string
-    {
-        return $this->get('EVT_created');
-    }
-
-
-    /**
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function description(): string
-    {
-        return $this->get('EVT_desc');
-    }
-
-
-    /**
-     * Runs do_shortcode and wpautop on the description
-     *
-     * @return string of html
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function description_filtered(): string
-    {
-        return $this->get_pretty('EVT_desc');
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function display_description(): bool
-    {
-        return $this->get('EVT_display_desc');
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function display_ticket_selector(): bool
-    {
-        return (bool) $this->get('EVT_display_ticket_selector');
-    }
-
-
-    /**
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function external_url(): ?string
-    {
-        return $this->get('EVT_external_URL') ?? '';
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function member_only(): bool
-    {
-        return $this->get('EVT_member_only');
-    }
-
-
-    /**
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function phone(): string
-    {
-        return $this->get('EVT_phone');
-    }
-
-
-    /**
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function modified(): string
-    {
-        return $this->get('EVT_modified');
-    }
-
-
-    /**
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function name(): string
-    {
-        return $this->get('EVT_name');
-    }
-
-
-    /**
-     * @return int
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function order(): int
-    {
-        return $this->get('EVT_order');
-    }
-
-
-    /**
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function default_registration_status(): string
-    {
-        $event_default_registration_status = $this->get('EVT_default_registration_status');
-        return ! empty($event_default_registration_status)
-            ? $event_default_registration_status
-            : EE_Registry::instance()->CFG->registration->default_STS_ID;
-    }
-
-
-    /**
-     * @param int|null    $num_words
-     * @param string|null $more
-     * @param bool        $not_full_desc
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function short_description(?int $num_words = 55, string $more = null, bool $not_full_desc = false): string
-    {
-        $short_desc = $this->get('EVT_short_desc');
-        if (! empty($short_desc) || $not_full_desc) {
-            return $short_desc;
-        }
-        $full_desc = $this->get('EVT_desc');
-        return wp_trim_words($full_desc, $num_words, $more);
-    }
-
-
-    /**
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function slug(): string
-    {
-        return $this->get('EVT_slug');
-    }
-
-
-    /**
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function timezone_string(): string
-    {
-        return $this->get('EVT_timezone_string');
-    }
-
-
-    /**
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @deprecated
-     */
-    public function visible_on(): string
-    {
-        EE_Error::doing_it_wrong(
-            __METHOD__,
-            esc_html__(
-                'This method has been deprecated and there is no replacement for it.',
-                'event_espresso'
-            ),
-            '5.0.0.rc.002'
-        );
-        return $this->get('EVT_visible_on');
-    }
-
-
-    /**
-     * @return int
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function wp_user(): int
-    {
-        return (int) $this->get('EVT_wp_user');
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function donations(): bool
-    {
-        return $this->get('EVT_donations');
-    }
-
-
-    /**
-     * @param int $limit
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_additional_limit(int $limit)
-    {
-        $this->set('EVT_additional_limit', $limit);
-    }
-
-
-    /**
-     * @param $created
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_created($created)
-    {
-        $this->set('EVT_created', $created);
-    }
-
-
-    /**
-     * @param $desc
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_description($desc)
-    {
-        $this->set('EVT_desc', $desc);
-    }
-
-
-    /**
-     * @param $display_desc
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_display_description($display_desc)
-    {
-        $this->set('EVT_display_desc', $display_desc);
-    }
-
-
-    /**
-     * @param $display_ticket_selector
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_display_ticket_selector($display_ticket_selector)
-    {
-        $this->set('EVT_display_ticket_selector', $display_ticket_selector);
-    }
-
-
-    /**
-     * @param $external_url
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_external_url($external_url)
-    {
-        $this->set('EVT_external_URL', $external_url);
-    }
-
-
-    /**
-     * @param $member_only
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_member_only($member_only)
-    {
-        $this->set('EVT_member_only', $member_only);
-    }
-
-
-    /**
-     * @param $event_phone
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_event_phone($event_phone)
-    {
-        $this->set('EVT_phone', $event_phone);
-    }
-
-
-    /**
-     * @param $modified
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_modified($modified)
-    {
-        $this->set('EVT_modified', $modified);
-    }
-
-
-    /**
-     * @param $name
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_name($name)
-    {
-        $this->set('EVT_name', $name);
-    }
-
-
-    /**
-     * @param $order
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_order($order)
-    {
-        $this->set('EVT_order', $order);
-    }
-
-
-    /**
-     * @param $short_desc
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_short_description($short_desc)
-    {
-        $this->set('EVT_short_desc', $short_desc);
-    }
-
-
-    /**
-     * @param $slug
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_slug($slug)
-    {
-        $this->set('EVT_slug', $slug);
-    }
-
-
-    /**
-     * @param $timezone_string
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_timezone_string($timezone_string)
-    {
-        $this->set('EVT_timezone_string', $timezone_string);
-    }
-
-
-    /**
-     * @param $visible_on
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @deprecated
-     */
-    public function set_visible_on($visible_on)
-    {
-        EE_Error::doing_it_wrong(
-            __METHOD__,
-            esc_html__(
-                'This method has been deprecated and there is no replacement for it.',
-                'event_espresso'
-            ),
-            '5.0.0.rc.002'
-        );
-        $this->set('EVT_visible_on', $visible_on);
-    }
-
-
-    /**
-     * @param $wp_user
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_wp_user($wp_user)
-    {
-        $this->set('EVT_wp_user', $wp_user);
-    }
-
-
-    /**
-     * @param $default_registration_status
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_default_registration_status($default_registration_status)
-    {
-        $this->set('EVT_default_registration_status', $default_registration_status);
-    }
-
-
-    /**
-     * @param $donations
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_donations($donations)
-    {
-        $this->set('EVT_donations', $donations);
-    }
-
-
-    /**
-     * Adds a venue to this event
-     *
-     * @param int|EE_Venue /int $venue_id_or_obj
-     * @return EE_Base_Class|EE_Venue
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function add_venue($venue_id_or_obj): EE_Venue
-    {
-        return $this->_add_relation_to($venue_id_or_obj, 'Venue');
-    }
-
-
-    /**
-     * Removes a venue from the event
-     *
-     * @param EE_Venue /int $venue_id_or_obj
-     * @return EE_Base_Class|EE_Venue
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function remove_venue($venue_id_or_obj): EE_Venue
-    {
-        $venue_id_or_obj = ! empty($venue_id_or_obj) ? $venue_id_or_obj : $this->venue();
-        return $this->_remove_relation_to($venue_id_or_obj, 'Venue');
-    }
-
-
-    /**
-     * Gets the venue related to the event. May provide additional $query_params if desired
-     *
-     * @param array $query_params
-     * @return int
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     */
-    public function venue_ID(array $query_params = []): int
-    {
-        $venue = $this->get_first_related('Venue', $query_params);
-        return $venue instanceof EE_Venue ? $venue->ID() : 0;
-    }
-
-
-    /**
-     * Gets the venue related to the event. May provide additional $query_params if desired
-     *
-     * @param array $query_params
-     * @return EE_Base_Class|EE_Venue|null
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     */
-    public function venue(array $query_params = []): ?EE_Venue
-    {
-        return $this->get_first_related('Venue', $query_params);
-    }
-
-
-    /**
-     * @param array $query_params
-     * @return EE_Base_Class[]|EE_Venue[]
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @deprecated 5.0.0.p
-     */
-    public function venues(array $query_params = []): array
-    {
-        $venue = $this->venue($query_params);
-        return $venue instanceof EE_Venue ? [$venue] : [];
-    }
-
-
-    /**
-     * check if event id is present and if event is published
-     *
-     * @return boolean true yes, false no
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    private function _has_ID_and_is_published(): bool
-    {
-        // first check if event id is present and not NULL,
-        // then check if this event is published (or any of the equivalent "published" statuses)
-        return
-            $this->ID() && $this->ID() !== null
-            && (
-                $this->status() === 'publish'
-                || $this->status() === EEM_Event::sold_out
-                || $this->status() === EEM_Event::postponed
-                || $this->status() === EEM_Event::cancelled
-            );
-    }
-
-
-    /**
-     * This simply compares the internal dates with NOW and determines if the event is upcoming or not.
-     *
-     * @return boolean true yes, false no
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function is_upcoming(): bool
-    {
-        // check if event id is present and if this event is published
-        if ($this->is_inactive()) {
-            return false;
-        }
-        // set initial value
-        $upcoming = false;
-        // next let's get all datetimes and loop through them
-        $datetimes = $this->datetimes_in_chronological_order();
-        foreach ($datetimes as $datetime) {
-            if ($datetime instanceof EE_Datetime) {
-                // if this dtt is expired then we continue cause one of the other datetimes might be upcoming.
-                if ($datetime->is_expired()) {
-                    continue;
-                }
-                // if this dtt is active then we return false.
-                if ($datetime->is_active()) {
-                    return false;
-                }
-                // otherwise let's check upcoming status
-                $upcoming = $datetime->is_upcoming();
-            }
-        }
-        return $upcoming;
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function is_active(): bool
-    {
-        // check if event id is present and if this event is published
-        if ($this->is_inactive()) {
-            return false;
-        }
-        // set initial value
-        $active = false;
-        // next let's get all datetimes and loop through them
-        $datetimes = $this->datetimes_in_chronological_order();
-        foreach ($datetimes as $datetime) {
-            if ($datetime instanceof EE_Datetime) {
-                // if this dtt is expired then we continue cause one of the other datetimes might be active.
-                if ($datetime->is_expired()) {
-                    continue;
-                }
-                // if this dtt is upcoming then we return false.
-                if ($datetime->is_upcoming()) {
-                    return false;
-                }
-                // otherwise let's check active status
-                $active = $datetime->is_active();
-            }
-        }
-        return $active;
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function is_expired(): bool
-    {
-        // check if event id is present and if this event is published
-        if ($this->is_inactive()) {
-            return false;
-        }
-        // set initial value
-        $expired = false;
-        // first let's get all datetimes and loop through them
-        $datetimes = $this->datetimes_in_chronological_order();
-        foreach ($datetimes as $datetime) {
-            if ($datetime instanceof EE_Datetime) {
-                // if this dtt is upcoming or active then we return false.
-                if ($datetime->is_upcoming() || $datetime->is_active()) {
-                    return false;
-                }
-                // otherwise let's check active status
-                $expired = $datetime->is_expired();
-            }
-        }
-        return $expired;
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function is_inactive(): bool
-    {
-        // check if event id is present and if this event is published
-        if ($this->_has_ID_and_is_published()) {
-            return false;
-        }
-        return true;
-    }
-
-
-    /**
-     * calculate spaces remaining based on "saleable" tickets
-     *
-     * @param array|null $tickets
-     * @param bool       $filtered
-     * @return int|float
-     * @throws EE_Error
-     * @throws DomainException
-     * @throws UnexpectedEntityException
-     * @throws ReflectionException
-     */
-    public function spaces_remaining(?array $tickets = [], ?bool $filtered = true)
-    {
-        $this->getAvailableSpacesCalculator()->setActiveTickets($tickets);
-        $spaces_remaining = $this->getAvailableSpacesCalculator()->spacesRemaining();
-        return $filtered
-            ? apply_filters(
-                'FHEE_EE_Event__spaces_remaining',
-                $spaces_remaining,
-                $this,
-                $tickets
-            )
-            : $spaces_remaining;
-    }
-
-
-    /**
-     *    perform_sold_out_status_check
-     *    checks all of this event's datetime  reg_limit - sold values to determine if ANY datetimes have spaces
-     *    available... if NOT, then the event status will get toggled to 'sold_out'
-     *
-     * @return bool    return the ACTUAL sold out state.
-     * @throws EE_Error
-     * @throws DomainException
-     * @throws UnexpectedEntityException
-     * @throws ReflectionException
-     */
-    public function perform_sold_out_status_check(): bool
-    {
-        // get all tickets
-        $tickets     = $this->tickets(
-            [
-                'default_where_conditions' => 'none',
-                'order_by'                 => ['TKT_qty' => 'ASC'],
-            ]
-        );
-        $all_expired = true;
-        foreach ($tickets as $ticket) {
-            if (! $ticket->is_expired()) {
-                $all_expired = false;
-                break;
-            }
-        }
-        // if all the tickets are just expired, then don't update the event status to sold out
-        if ($all_expired) {
-            return true;
-        }
-        $spaces_remaining = $this->spaces_remaining($tickets);
-        if ($spaces_remaining < 1) {
-            if ($this->status() !== EEM_CPT_Base::post_status_private) {
-                $this->set_status(EEM_Event::sold_out);
-                $this->save();
-            }
-            $sold_out = true;
-        } else {
-            $sold_out = false;
-            // was event previously marked as sold out ?
-            if ($this->status() === EEM_Event::sold_out) {
-                // revert status to previous value, if it was set
-                $previous_event_status = $this->get_post_meta('_previous_event_status', true);
-                if ($previous_event_status) {
-                    $this->set_status($previous_event_status);
-                    $this->save();
-                }
-            }
-        }
-        do_action('AHEE__EE_Event__perform_sold_out_status_check__end', $this, $sold_out, $spaces_remaining, $tickets);
-        return $sold_out;
-    }
-
-
-    /**
-     * This returns the total remaining spaces for sale on this event.
-     *
-     * @return int|float
-     * @throws EE_Error
-     * @throws DomainException
-     * @throws UnexpectedEntityException
-     * @throws ReflectionException
-     * @uses EE_Event::total_available_spaces()
-     */
-    public function spaces_remaining_for_sale()
-    {
-        return $this->total_available_spaces(true);
-    }
-
-
-    /**
-     * This returns the total spaces available for an event
-     * while considering all the quantities on the tickets and the reg limits
-     * on the datetimes attached to this event.
-     *
-     * @param bool $consider_sold   Whether to consider any tickets that have already sold in our calculation.
-     *                              If this is false, then we return the most tickets that could ever be sold
-     *                              for this event with the datetime and tickets setup on the event under optimal
-     *                              selling conditions.  Otherwise we return a live calculation of spaces available
-     *                              based on tickets sold.  Depending on setup and stage of sales, this
-     *                              may appear to equal remaining tickets.  However, the more tickets are
-     *                              sold out, the more accurate the "live" total is.
-     * @return int|float
-     * @throws EE_Error
-     * @throws DomainException
-     * @throws UnexpectedEntityException
-     * @throws ReflectionException
-     */
-    public function total_available_spaces(bool $consider_sold = false)
-    {
-        $spaces_available = $consider_sold
-            ? $this->getAvailableSpacesCalculator()->spacesRemaining()
-            : $this->getAvailableSpacesCalculator()->totalSpacesAvailable();
-        return apply_filters(
-            'FHEE_EE_Event__total_available_spaces__spaces_available',
-            $spaces_available,
-            $this,
-            $this->getAvailableSpacesCalculator()->getDatetimes(),
-            $this->getAvailableSpacesCalculator()->getActiveTickets()
-        );
-    }
-
-
-    /**
-     * Checks if the event is set to sold out
-     *
-     * @param bool $actual  whether or not to perform calculations to not only figure the
-     *                      actual status but also to flip the status if necessary to sold
-     *                      out If false, we just check the existing status of the event
-     * @return boolean
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function is_sold_out(bool $actual = false): bool
-    {
-        if (! $actual) {
-            return $this->status() === EEM_Event::sold_out;
-        }
-        return $this->perform_sold_out_status_check();
-    }
-
-
-    /**
-     * Checks if the event is marked as postponed
-     *
-     * @return boolean
-     */
-    public function is_postponed(): bool
-    {
-        return $this->status() === EEM_Event::postponed;
-    }
-
-
-    /**
-     * Checks if the event is marked as cancelled
-     *
-     * @return boolean
-     */
-    public function is_cancelled(): bool
-    {
-        return $this->status() === EEM_Event::cancelled;
-    }
-
-
-    /**
-     * Get the logical active status in a hierarchical order for all the datetimes.  Note
-     * Basically, we order the datetimes by EVT_start_date.  Then first test on whether the event is published.  If its
-     * NOT published then we test for whether its expired or not.  IF it IS published then we test first on whether an
-     * event has any active dates.  If no active dates then we check for any upcoming dates.  If no upcoming dates then
-     * the event is considered expired.
-     * NOTE: this method does NOT calculate whether the datetimes are sold out when event is published.  Sold Out is a
-     * status set on the EVENT when it is not published and thus is done
-     *
-     * @param bool $reset
-     * @return bool | string - based on EE_Datetime active constants or FALSE if error.
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_active_status(bool $reset = false)
-    {
-        // if the active status has already been set, then just use that value (unless we are resetting it)
-        if (! empty($this->_active_status) && ! $reset) {
-            return $this->_active_status;
-        }
-        // first check if event id is present on this object
-        if (! $this->ID()) {
-            return false;
-        }
-        $where_params_for_event = [['EVT_ID' => $this->ID()]];
-        // if event is published:
-        if (
-            $this->status() === EEM_CPT_Base::post_status_publish
-            || $this->status() === EEM_CPT_Base::post_status_private
-        ) {
-            // active?
-            if (
-                EEM_Datetime::instance()->get_datetime_count_for_status(
-                    EE_Datetime::active,
-                    $where_params_for_event
-                ) > 0
-            ) {
-                $this->_active_status = EE_Datetime::active;
-            } else {
-                // upcoming?
-                if (
-                    EEM_Datetime::instance()->get_datetime_count_for_status(
-                        EE_Datetime::upcoming,
-                        $where_params_for_event
-                    ) > 0
-                ) {
-                    $this->_active_status = EE_Datetime::upcoming;
-                } else {
-                    // expired?
-                    if (
-                        EEM_Datetime::instance()->get_datetime_count_for_status(
-                            EE_Datetime::expired,
-                            $where_params_for_event
-                        ) > 0
-                    ) {
-                        $this->_active_status = EE_Datetime::expired;
-                    } else {
-                        // it would be odd if things make it this far
-                        // because it basically means there are no datetimes attached to the event.
-                        // So in this case it will just be considered inactive.
-                        $this->_active_status = EE_Datetime::inactive;
-                    }
-                }
-            }
-        } else {
-            // the event is not published, so let's just set it's active status according to its' post status
-            switch ($this->status()) {
-                case EEM_Event::sold_out:
-                    $this->_active_status = EE_Datetime::sold_out;
-                    break;
-                case EEM_Event::cancelled:
-                    $this->_active_status = EE_Datetime::cancelled;
-                    break;
-                case EEM_Event::postponed:
-                    $this->_active_status = EE_Datetime::postponed;
-                    break;
-                default:
-                    $this->_active_status = EE_Datetime::inactive;
-            }
-        }
-        return $this->_active_status;
-    }
-
-
-    /**
-     *    pretty_active_status
-     *
-     * @param boolean $echo whether to return (FALSE), or echo out the result (TRUE)
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function pretty_active_status(bool $echo = true): string
-    {
-        $active_status = $this->get_active_status();
-        $status        = "
+	/**
+	 * cached value for the the logical active status for the event
+	 *
+	 * @see get_active_status()
+	 * @var string
+	 */
+	protected $_active_status = '';
+
+	/**
+	 * This is just used for caching the Primary Datetime for the Event on initial retrieval
+	 *
+	 * @var EE_Datetime
+	 */
+	protected $_Primary_Datetime;
+
+	/**
+	 * @var EventSpacesCalculator $available_spaces_calculator
+	 */
+	protected $available_spaces_calculator;
+
+
+	/**
+	 * @param array  $props_n_values          incoming values
+	 * @param string $timezone                incoming timezone (if not set the timezone set for the website will be
+	 *                                        used.)
+	 * @param array  $date_formats            incoming date_formats in an array where the first value is the
+	 *                                        date_format and the second value is the time format
+	 * @return EE_Event
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public static function new_instance($props_n_values = [], $timezone = '', $date_formats = []): EE_Event
+	{
+		$has_object = parent::_check_for_object($props_n_values, __CLASS__, $timezone, $date_formats);
+		return $has_object ?: new self($props_n_values, false, $timezone, $date_formats);
+	}
+
+
+	/**
+	 * @param array  $props_n_values  incoming values from the database
+	 * @param string $timezone        incoming timezone as set by the model.  If not set the timezone for
+	 *                                the website will be used.
+	 * @return EE_Event
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public static function new_instance_from_db($props_n_values = [], $timezone = ''): EE_Event
+	{
+		return new self($props_n_values, true, $timezone);
+	}
+
+
+	/**
+	 * @return EventSpacesCalculator
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function getAvailableSpacesCalculator(): EventSpacesCalculator
+	{
+		if (! $this->available_spaces_calculator instanceof EventSpacesCalculator) {
+			$this->available_spaces_calculator = new EventSpacesCalculator($this);
+		}
+		return $this->available_spaces_calculator;
+	}
+
+
+	/**
+	 * Overrides parent set() method so that all calls to set( 'status', $status ) can be routed to internal methods
+	 *
+	 * @param string $field_name
+	 * @param mixed  $field_value
+	 * @param bool   $use_default
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set($field_name, $field_value, $use_default = false)
+	{
+		switch ($field_name) {
+			case 'status':
+				$this->set_status($field_value, $use_default);
+				break;
+			default:
+				parent::set($field_name, $field_value, $use_default);
+		}
+	}
+
+
+	/**
+	 *    set_status
+	 * Checks if event status is being changed to SOLD OUT
+	 * and updates event meta data with previous event status
+	 * so that we can revert things if/when the event is no longer sold out
+	 *
+	 * @param string $status
+	 * @param bool   $use_default
+	 * @return void
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_status($status = '', $use_default = false)
+	{
+		// if nothing is set, and we aren't explicitly wanting to reset the status, then just leave
+		if (empty($status) && ! $use_default) {
+			return;
+		}
+		// get current Event status
+		$old_status = $this->status();
+		// if status has changed
+		if ($old_status !== $status) {
+			// TO sold_out
+			if ($status === EEM_Event::sold_out) {
+				// save the previous event status so that we can revert if the event is no longer sold out
+				$this->add_post_meta('_previous_event_status', $old_status);
+				do_action('AHEE__EE_Event__set_status__to_sold_out', $this, $old_status, $status);
+				// OR FROM  sold_out
+			} elseif ($old_status === EEM_Event::sold_out) {
+				$this->delete_post_meta('_previous_event_status');
+				do_action('AHEE__EE_Event__set_status__from_sold_out', $this, $old_status, $status);
+			}
+			// clear out the active status so that it gets reset the next time it is requested
+			$this->_active_status = null;
+			// update status
+			parent::set('status', $status, $use_default);
+			do_action('AHEE__EE_Event__set_status__after_update', $this);
+			return;
+		}
+		// even though the old value matches the new value, it's still good to
+		// allow the parent set method to have a say
+		parent::set('status', $status, $use_default);
+	}
+
+
+	/**
+	 * Gets all the datetimes for this event
+	 *
+	 * @param array|null $query_params
+	 * @return EE_Base_Class[]|EE_Datetime[]
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 */
+	public function datetimes(?array $query_params = []): array
+	{
+		return $this->get_many_related('Datetime', $query_params);
+	}
+
+
+	/**
+	 * Gets all the datetimes for this event that are currently ACTIVE,
+	 * meaning the datetime has started and has not yet ended.
+	 *
+	 * @param int|null   $start_date   timestamp to use for event date start time, defaults to NOW unless set to 0
+	 * @param array|null $query_params will recursively replace default values
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 */
+	public function activeDatetimes(?int $start_date, ?array $query_params = []): array
+	{
+		// if start date is null, then use current time
+		$start_date = $start_date ?? time();
+		$where      = [];
+		if ($start_date) {
+			$where['DTT_EVT_start'] = ['<', $start_date];
+			$where['DTT_EVT_end']   = ['>', time()];
+		}
+		$query_params = array_replace_recursive(
+			[
+				$where,
+				'order_by' => ['DTT_EVT_start' => 'ASC'],
+			],
+			$query_params
+		);
+		return $this->get_many_related('Datetime', $query_params);
+	}
+
+
+	/**
+	 * Gets all the datetimes for this event, ordered by DTT_EVT_start in ascending order
+	 *
+	 * @return EE_Base_Class[]|EE_Datetime[]
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function datetimes_in_chronological_order(): array
+	{
+		return $this->get_many_related('Datetime', ['order_by' => ['DTT_EVT_start' => 'ASC']]);
+	}
+
+
+	/**
+	 * Gets all the datetimes for this event, ordered by the DTT_order on the datetime.
+	 * @darren, we should probably UNSET timezone on the EEM_Datetime model
+	 * after running our query, so that this timezone isn't set for EVERY query
+	 * on EEM_Datetime for the rest of the request, no?
+	 *
+	 * @param bool     $show_expired whether or not to include expired events
+	 * @param bool     $show_deleted whether or not to include deleted events
+	 * @param int|null $limit
+	 * @return EE_Datetime[]
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function datetimes_ordered(bool $show_expired = true, bool $show_deleted = false, ?int $limit = null): array
+	{
+		return EEM_Datetime::instance($this->_timezone)->get_datetimes_for_event_ordered_by_DTT_order(
+			$this->ID(),
+			$show_expired,
+			$show_deleted,
+			$limit
+		);
+	}
+
+
+	/**
+	 * Returns one related datetime. Mostly only used by some legacy code.
+	 *
+	 * @return EE_Base_Class|EE_Datetime
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function first_datetime(): EE_Datetime
+	{
+		return $this->get_first_related('Datetime');
+	}
+
+
+	/**
+	 * Returns the 'primary' datetime for the event
+	 *
+	 * @param bool $try_to_exclude_expired
+	 * @param bool $try_to_exclude_deleted
+	 * @return EE_Datetime|null
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function primary_datetime(
+		bool $try_to_exclude_expired = true,
+		bool $try_to_exclude_deleted = true
+	): ?EE_Datetime {
+		if (! empty($this->_Primary_Datetime)) {
+			return $this->_Primary_Datetime;
+		}
+		$this->_Primary_Datetime = EEM_Datetime::instance($this->_timezone)->get_primary_datetime_for_event(
+			$this->ID(),
+			$try_to_exclude_expired,
+			$try_to_exclude_deleted
+		);
+		return $this->_Primary_Datetime;
+	}
+
+
+	/**
+	 * Gets all the tickets available for purchase of this event
+	 *
+	 * @param array|null $query_params
+	 * @return EE_Base_Class[]|EE_Ticket[]
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 */
+	public function tickets(?array $query_params = []): array
+	{
+		// first get all datetimes
+		$datetimes = $this->datetimes_ordered();
+		if (! $datetimes) {
+			return [];
+		}
+		$datetime_ids = [];
+		foreach ($datetimes as $datetime) {
+			$datetime_ids[] = $datetime->ID();
+		}
+		$where_params = ['Datetime.DTT_ID' => ['IN', $datetime_ids]];
+		// if incoming $query_params has where conditions let's merge but not override existing.
+		if (is_array($query_params) && isset($query_params[0])) {
+			$where_params = array_merge($query_params[0], $where_params);
+			unset($query_params[0]);
+		}
+		// now add $where_params to $query_params
+		$query_params[0] = $where_params;
+		return EEM_Ticket::instance()->get_all($query_params);
+	}
+
+
+	/**
+	 * get all unexpired not-trashed tickets
+	 *
+	 * @return EE_Ticket[]
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function active_tickets(): array
+	{
+		return $this->tickets(
+			[
+				[
+					'TKT_end_date' => ['>=', EEM_Ticket::instance()->current_time_for_query('TKT_end_date')],
+					'TKT_deleted'  => false,
+				],
+			]
+		);
+	}
+
+
+	/**
+	 * @return int
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function additional_limit(): int
+	{
+		return $this->get('EVT_additional_limit');
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function allow_overflow(): bool
+	{
+		return $this->get('EVT_allow_overflow');
+	}
+
+
+	/**
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function created(): string
+	{
+		return $this->get('EVT_created');
+	}
+
+
+	/**
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function description(): string
+	{
+		return $this->get('EVT_desc');
+	}
+
+
+	/**
+	 * Runs do_shortcode and wpautop on the description
+	 *
+	 * @return string of html
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function description_filtered(): string
+	{
+		return $this->get_pretty('EVT_desc');
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function display_description(): bool
+	{
+		return $this->get('EVT_display_desc');
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function display_ticket_selector(): bool
+	{
+		return (bool) $this->get('EVT_display_ticket_selector');
+	}
+
+
+	/**
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function external_url(): ?string
+	{
+		return $this->get('EVT_external_URL') ?? '';
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function member_only(): bool
+	{
+		return $this->get('EVT_member_only');
+	}
+
+
+	/**
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function phone(): string
+	{
+		return $this->get('EVT_phone');
+	}
+
+
+	/**
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function modified(): string
+	{
+		return $this->get('EVT_modified');
+	}
+
+
+	/**
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function name(): string
+	{
+		return $this->get('EVT_name');
+	}
+
+
+	/**
+	 * @return int
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function order(): int
+	{
+		return $this->get('EVT_order');
+	}
+
+
+	/**
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function default_registration_status(): string
+	{
+		$event_default_registration_status = $this->get('EVT_default_registration_status');
+		return ! empty($event_default_registration_status)
+			? $event_default_registration_status
+			: EE_Registry::instance()->CFG->registration->default_STS_ID;
+	}
+
+
+	/**
+	 * @param int|null    $num_words
+	 * @param string|null $more
+	 * @param bool        $not_full_desc
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function short_description(?int $num_words = 55, string $more = null, bool $not_full_desc = false): string
+	{
+		$short_desc = $this->get('EVT_short_desc');
+		if (! empty($short_desc) || $not_full_desc) {
+			return $short_desc;
+		}
+		$full_desc = $this->get('EVT_desc');
+		return wp_trim_words($full_desc, $num_words, $more);
+	}
+
+
+	/**
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function slug(): string
+	{
+		return $this->get('EVT_slug');
+	}
+
+
+	/**
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function timezone_string(): string
+	{
+		return $this->get('EVT_timezone_string');
+	}
+
+
+	/**
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @deprecated
+	 */
+	public function visible_on(): string
+	{
+		EE_Error::doing_it_wrong(
+			__METHOD__,
+			esc_html__(
+				'This method has been deprecated and there is no replacement for it.',
+				'event_espresso'
+			),
+			'5.0.0.rc.002'
+		);
+		return $this->get('EVT_visible_on');
+	}
+
+
+	/**
+	 * @return int
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function wp_user(): int
+	{
+		return (int) $this->get('EVT_wp_user');
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function donations(): bool
+	{
+		return $this->get('EVT_donations');
+	}
+
+
+	/**
+	 * @param int $limit
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_additional_limit(int $limit)
+	{
+		$this->set('EVT_additional_limit', $limit);
+	}
+
+
+	/**
+	 * @param $created
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_created($created)
+	{
+		$this->set('EVT_created', $created);
+	}
+
+
+	/**
+	 * @param $desc
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_description($desc)
+	{
+		$this->set('EVT_desc', $desc);
+	}
+
+
+	/**
+	 * @param $display_desc
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_display_description($display_desc)
+	{
+		$this->set('EVT_display_desc', $display_desc);
+	}
+
+
+	/**
+	 * @param $display_ticket_selector
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_display_ticket_selector($display_ticket_selector)
+	{
+		$this->set('EVT_display_ticket_selector', $display_ticket_selector);
+	}
+
+
+	/**
+	 * @param $external_url
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_external_url($external_url)
+	{
+		$this->set('EVT_external_URL', $external_url);
+	}
+
+
+	/**
+	 * @param $member_only
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_member_only($member_only)
+	{
+		$this->set('EVT_member_only', $member_only);
+	}
+
+
+	/**
+	 * @param $event_phone
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_event_phone($event_phone)
+	{
+		$this->set('EVT_phone', $event_phone);
+	}
+
+
+	/**
+	 * @param $modified
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_modified($modified)
+	{
+		$this->set('EVT_modified', $modified);
+	}
+
+
+	/**
+	 * @param $name
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_name($name)
+	{
+		$this->set('EVT_name', $name);
+	}
+
+
+	/**
+	 * @param $order
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_order($order)
+	{
+		$this->set('EVT_order', $order);
+	}
+
+
+	/**
+	 * @param $short_desc
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_short_description($short_desc)
+	{
+		$this->set('EVT_short_desc', $short_desc);
+	}
+
+
+	/**
+	 * @param $slug
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_slug($slug)
+	{
+		$this->set('EVT_slug', $slug);
+	}
+
+
+	/**
+	 * @param $timezone_string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_timezone_string($timezone_string)
+	{
+		$this->set('EVT_timezone_string', $timezone_string);
+	}
+
+
+	/**
+	 * @param $visible_on
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @deprecated
+	 */
+	public function set_visible_on($visible_on)
+	{
+		EE_Error::doing_it_wrong(
+			__METHOD__,
+			esc_html__(
+				'This method has been deprecated and there is no replacement for it.',
+				'event_espresso'
+			),
+			'5.0.0.rc.002'
+		);
+		$this->set('EVT_visible_on', $visible_on);
+	}
+
+
+	/**
+	 * @param $wp_user
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_wp_user($wp_user)
+	{
+		$this->set('EVT_wp_user', $wp_user);
+	}
+
+
+	/**
+	 * @param $default_registration_status
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_default_registration_status($default_registration_status)
+	{
+		$this->set('EVT_default_registration_status', $default_registration_status);
+	}
+
+
+	/**
+	 * @param $donations
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_donations($donations)
+	{
+		$this->set('EVT_donations', $donations);
+	}
+
+
+	/**
+	 * Adds a venue to this event
+	 *
+	 * @param int|EE_Venue /int $venue_id_or_obj
+	 * @return EE_Base_Class|EE_Venue
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function add_venue($venue_id_or_obj): EE_Venue
+	{
+		return $this->_add_relation_to($venue_id_or_obj, 'Venue');
+	}
+
+
+	/**
+	 * Removes a venue from the event
+	 *
+	 * @param EE_Venue /int $venue_id_or_obj
+	 * @return EE_Base_Class|EE_Venue
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function remove_venue($venue_id_or_obj): EE_Venue
+	{
+		$venue_id_or_obj = ! empty($venue_id_or_obj) ? $venue_id_or_obj : $this->venue();
+		return $this->_remove_relation_to($venue_id_or_obj, 'Venue');
+	}
+
+
+	/**
+	 * Gets the venue related to the event. May provide additional $query_params if desired
+	 *
+	 * @param array $query_params
+	 * @return int
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 */
+	public function venue_ID(array $query_params = []): int
+	{
+		$venue = $this->get_first_related('Venue', $query_params);
+		return $venue instanceof EE_Venue ? $venue->ID() : 0;
+	}
+
+
+	/**
+	 * Gets the venue related to the event. May provide additional $query_params if desired
+	 *
+	 * @param array $query_params
+	 * @return EE_Base_Class|EE_Venue|null
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 */
+	public function venue(array $query_params = []): ?EE_Venue
+	{
+		return $this->get_first_related('Venue', $query_params);
+	}
+
+
+	/**
+	 * @param array $query_params
+	 * @return EE_Base_Class[]|EE_Venue[]
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @deprecated 5.0.0.p
+	 */
+	public function venues(array $query_params = []): array
+	{
+		$venue = $this->venue($query_params);
+		return $venue instanceof EE_Venue ? [$venue] : [];
+	}
+
+
+	/**
+	 * check if event id is present and if event is published
+	 *
+	 * @return boolean true yes, false no
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	private function _has_ID_and_is_published(): bool
+	{
+		// first check if event id is present and not NULL,
+		// then check if this event is published (or any of the equivalent "published" statuses)
+		return
+			$this->ID() && $this->ID() !== null
+			&& (
+				$this->status() === 'publish'
+				|| $this->status() === EEM_Event::sold_out
+				|| $this->status() === EEM_Event::postponed
+				|| $this->status() === EEM_Event::cancelled
+			);
+	}
+
+
+	/**
+	 * This simply compares the internal dates with NOW and determines if the event is upcoming or not.
+	 *
+	 * @return boolean true yes, false no
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function is_upcoming(): bool
+	{
+		// check if event id is present and if this event is published
+		if ($this->is_inactive()) {
+			return false;
+		}
+		// set initial value
+		$upcoming = false;
+		// next let's get all datetimes and loop through them
+		$datetimes = $this->datetimes_in_chronological_order();
+		foreach ($datetimes as $datetime) {
+			if ($datetime instanceof EE_Datetime) {
+				// if this dtt is expired then we continue cause one of the other datetimes might be upcoming.
+				if ($datetime->is_expired()) {
+					continue;
+				}
+				// if this dtt is active then we return false.
+				if ($datetime->is_active()) {
+					return false;
+				}
+				// otherwise let's check upcoming status
+				$upcoming = $datetime->is_upcoming();
+			}
+		}
+		return $upcoming;
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function is_active(): bool
+	{
+		// check if event id is present and if this event is published
+		if ($this->is_inactive()) {
+			return false;
+		}
+		// set initial value
+		$active = false;
+		// next let's get all datetimes and loop through them
+		$datetimes = $this->datetimes_in_chronological_order();
+		foreach ($datetimes as $datetime) {
+			if ($datetime instanceof EE_Datetime) {
+				// if this dtt is expired then we continue cause one of the other datetimes might be active.
+				if ($datetime->is_expired()) {
+					continue;
+				}
+				// if this dtt is upcoming then we return false.
+				if ($datetime->is_upcoming()) {
+					return false;
+				}
+				// otherwise let's check active status
+				$active = $datetime->is_active();
+			}
+		}
+		return $active;
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function is_expired(): bool
+	{
+		// check if event id is present and if this event is published
+		if ($this->is_inactive()) {
+			return false;
+		}
+		// set initial value
+		$expired = false;
+		// first let's get all datetimes and loop through them
+		$datetimes = $this->datetimes_in_chronological_order();
+		foreach ($datetimes as $datetime) {
+			if ($datetime instanceof EE_Datetime) {
+				// if this dtt is upcoming or active then we return false.
+				if ($datetime->is_upcoming() || $datetime->is_active()) {
+					return false;
+				}
+				// otherwise let's check active status
+				$expired = $datetime->is_expired();
+			}
+		}
+		return $expired;
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function is_inactive(): bool
+	{
+		// check if event id is present and if this event is published
+		if ($this->_has_ID_and_is_published()) {
+			return false;
+		}
+		return true;
+	}
+
+
+	/**
+	 * calculate spaces remaining based on "saleable" tickets
+	 *
+	 * @param array|null $tickets
+	 * @param bool       $filtered
+	 * @return int|float
+	 * @throws EE_Error
+	 * @throws DomainException
+	 * @throws UnexpectedEntityException
+	 * @throws ReflectionException
+	 */
+	public function spaces_remaining(?array $tickets = [], ?bool $filtered = true)
+	{
+		$this->getAvailableSpacesCalculator()->setActiveTickets($tickets);
+		$spaces_remaining = $this->getAvailableSpacesCalculator()->spacesRemaining();
+		return $filtered
+			? apply_filters(
+				'FHEE_EE_Event__spaces_remaining',
+				$spaces_remaining,
+				$this,
+				$tickets
+			)
+			: $spaces_remaining;
+	}
+
+
+	/**
+	 *    perform_sold_out_status_check
+	 *    checks all of this event's datetime  reg_limit - sold values to determine if ANY datetimes have spaces
+	 *    available... if NOT, then the event status will get toggled to 'sold_out'
+	 *
+	 * @return bool    return the ACTUAL sold out state.
+	 * @throws EE_Error
+	 * @throws DomainException
+	 * @throws UnexpectedEntityException
+	 * @throws ReflectionException
+	 */
+	public function perform_sold_out_status_check(): bool
+	{
+		// get all tickets
+		$tickets     = $this->tickets(
+			[
+				'default_where_conditions' => 'none',
+				'order_by'                 => ['TKT_qty' => 'ASC'],
+			]
+		);
+		$all_expired = true;
+		foreach ($tickets as $ticket) {
+			if (! $ticket->is_expired()) {
+				$all_expired = false;
+				break;
+			}
+		}
+		// if all the tickets are just expired, then don't update the event status to sold out
+		if ($all_expired) {
+			return true;
+		}
+		$spaces_remaining = $this->spaces_remaining($tickets);
+		if ($spaces_remaining < 1) {
+			if ($this->status() !== EEM_CPT_Base::post_status_private) {
+				$this->set_status(EEM_Event::sold_out);
+				$this->save();
+			}
+			$sold_out = true;
+		} else {
+			$sold_out = false;
+			// was event previously marked as sold out ?
+			if ($this->status() === EEM_Event::sold_out) {
+				// revert status to previous value, if it was set
+				$previous_event_status = $this->get_post_meta('_previous_event_status', true);
+				if ($previous_event_status) {
+					$this->set_status($previous_event_status);
+					$this->save();
+				}
+			}
+		}
+		do_action('AHEE__EE_Event__perform_sold_out_status_check__end', $this, $sold_out, $spaces_remaining, $tickets);
+		return $sold_out;
+	}
+
+
+	/**
+	 * This returns the total remaining spaces for sale on this event.
+	 *
+	 * @return int|float
+	 * @throws EE_Error
+	 * @throws DomainException
+	 * @throws UnexpectedEntityException
+	 * @throws ReflectionException
+	 * @uses EE_Event::total_available_spaces()
+	 */
+	public function spaces_remaining_for_sale()
+	{
+		return $this->total_available_spaces(true);
+	}
+
+
+	/**
+	 * This returns the total spaces available for an event
+	 * while considering all the quantities on the tickets and the reg limits
+	 * on the datetimes attached to this event.
+	 *
+	 * @param bool $consider_sold   Whether to consider any tickets that have already sold in our calculation.
+	 *                              If this is false, then we return the most tickets that could ever be sold
+	 *                              for this event with the datetime and tickets setup on the event under optimal
+	 *                              selling conditions.  Otherwise we return a live calculation of spaces available
+	 *                              based on tickets sold.  Depending on setup and stage of sales, this
+	 *                              may appear to equal remaining tickets.  However, the more tickets are
+	 *                              sold out, the more accurate the "live" total is.
+	 * @return int|float
+	 * @throws EE_Error
+	 * @throws DomainException
+	 * @throws UnexpectedEntityException
+	 * @throws ReflectionException
+	 */
+	public function total_available_spaces(bool $consider_sold = false)
+	{
+		$spaces_available = $consider_sold
+			? $this->getAvailableSpacesCalculator()->spacesRemaining()
+			: $this->getAvailableSpacesCalculator()->totalSpacesAvailable();
+		return apply_filters(
+			'FHEE_EE_Event__total_available_spaces__spaces_available',
+			$spaces_available,
+			$this,
+			$this->getAvailableSpacesCalculator()->getDatetimes(),
+			$this->getAvailableSpacesCalculator()->getActiveTickets()
+		);
+	}
+
+
+	/**
+	 * Checks if the event is set to sold out
+	 *
+	 * @param bool $actual  whether or not to perform calculations to not only figure the
+	 *                      actual status but also to flip the status if necessary to sold
+	 *                      out If false, we just check the existing status of the event
+	 * @return boolean
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function is_sold_out(bool $actual = false): bool
+	{
+		if (! $actual) {
+			return $this->status() === EEM_Event::sold_out;
+		}
+		return $this->perform_sold_out_status_check();
+	}
+
+
+	/**
+	 * Checks if the event is marked as postponed
+	 *
+	 * @return boolean
+	 */
+	public function is_postponed(): bool
+	{
+		return $this->status() === EEM_Event::postponed;
+	}
+
+
+	/**
+	 * Checks if the event is marked as cancelled
+	 *
+	 * @return boolean
+	 */
+	public function is_cancelled(): bool
+	{
+		return $this->status() === EEM_Event::cancelled;
+	}
+
+
+	/**
+	 * Get the logical active status in a hierarchical order for all the datetimes.  Note
+	 * Basically, we order the datetimes by EVT_start_date.  Then first test on whether the event is published.  If its
+	 * NOT published then we test for whether its expired or not.  IF it IS published then we test first on whether an
+	 * event has any active dates.  If no active dates then we check for any upcoming dates.  If no upcoming dates then
+	 * the event is considered expired.
+	 * NOTE: this method does NOT calculate whether the datetimes are sold out when event is published.  Sold Out is a
+	 * status set on the EVENT when it is not published and thus is done
+	 *
+	 * @param bool $reset
+	 * @return bool | string - based on EE_Datetime active constants or FALSE if error.
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_active_status(bool $reset = false)
+	{
+		// if the active status has already been set, then just use that value (unless we are resetting it)
+		if (! empty($this->_active_status) && ! $reset) {
+			return $this->_active_status;
+		}
+		// first check if event id is present on this object
+		if (! $this->ID()) {
+			return false;
+		}
+		$where_params_for_event = [['EVT_ID' => $this->ID()]];
+		// if event is published:
+		if (
+			$this->status() === EEM_CPT_Base::post_status_publish
+			|| $this->status() === EEM_CPT_Base::post_status_private
+		) {
+			// active?
+			if (
+				EEM_Datetime::instance()->get_datetime_count_for_status(
+					EE_Datetime::active,
+					$where_params_for_event
+				) > 0
+			) {
+				$this->_active_status = EE_Datetime::active;
+			} else {
+				// upcoming?
+				if (
+					EEM_Datetime::instance()->get_datetime_count_for_status(
+						EE_Datetime::upcoming,
+						$where_params_for_event
+					) > 0
+				) {
+					$this->_active_status = EE_Datetime::upcoming;
+				} else {
+					// expired?
+					if (
+						EEM_Datetime::instance()->get_datetime_count_for_status(
+							EE_Datetime::expired,
+							$where_params_for_event
+						) > 0
+					) {
+						$this->_active_status = EE_Datetime::expired;
+					} else {
+						// it would be odd if things make it this far
+						// because it basically means there are no datetimes attached to the event.
+						// So in this case it will just be considered inactive.
+						$this->_active_status = EE_Datetime::inactive;
+					}
+				}
+			}
+		} else {
+			// the event is not published, so let's just set it's active status according to its' post status
+			switch ($this->status()) {
+				case EEM_Event::sold_out:
+					$this->_active_status = EE_Datetime::sold_out;
+					break;
+				case EEM_Event::cancelled:
+					$this->_active_status = EE_Datetime::cancelled;
+					break;
+				case EEM_Event::postponed:
+					$this->_active_status = EE_Datetime::postponed;
+					break;
+				default:
+					$this->_active_status = EE_Datetime::inactive;
+			}
+		}
+		return $this->_active_status;
+	}
+
+
+	/**
+	 *    pretty_active_status
+	 *
+	 * @param boolean $echo whether to return (FALSE), or echo out the result (TRUE)
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function pretty_active_status(bool $echo = true): string
+	{
+		$active_status = $this->get_active_status();
+		$status        = "
         <span class='event-active-status event-active-status-$active_status ee-status ee-status-bg--$active_status'>
             " . EEH_Template::pretty_status($active_status, false, 'sentence') . "
         </span >";
-        if ($echo) {
-            echo wp_kses($status, AllowedTags::getAllowedTags());
-            return '';
-        }
-        return $status;
-    }
-
-
-    /**
-     * @return bool|int
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_number_of_tickets_sold()
-    {
-        $tkt_sold = 0;
-        if (! $this->ID()) {
-            return 0;
-        }
-        $datetimes = $this->datetimes();
-        foreach ($datetimes as $datetime) {
-            if ($datetime instanceof EE_Datetime) {
-                $tkt_sold += $datetime->sold();
-            }
-        }
-        return $tkt_sold;
-    }
-
-
-    /**
-     * This just returns a count of all the registrations for this event
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_count_of_all_registrations(): int
-    {
-        return EEM_Event::instance()->count_related($this, 'Registration');
-    }
-
-
-    /**
-     * This returns the ticket with the earliest start time that is
-     * available for this event (across all datetimes attached to the event)
-     *
-     * @return EE_Base_Class|EE_Ticket|null
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_ticket_with_earliest_start_time()
-    {
-        $where['Datetime.EVT_ID'] = $this->ID();
-        $query_params             = [$where, 'order_by' => ['TKT_start_date' => 'ASC']];
-        return EE_Registry::instance()->load_model('Ticket')->get_one($query_params);
-    }
-
-
-    /**
-     * This returns the ticket with the latest end time that is available
-     * for this event (across all datetimes attached to the event)
-     *
-     * @return EE_Base_Class|EE_Ticket|null
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_ticket_with_latest_end_time()
-    {
-        $where['Datetime.EVT_ID'] = $this->ID();
-        $query_params             = [$where, 'order_by' => ['TKT_end_date' => 'DESC']];
-        return EE_Registry::instance()->load_model('Ticket')->get_one($query_params);
-    }
-
-
-    /**
-     * This returns the number of different ticket types currently on sale for this event.
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function countTicketsOnSale(): int
-    {
-        $where = [
-            'Datetime.EVT_ID' => $this->ID(),
-            'TKT_start_date'  => ['<', time()],
-            'TKT_end_date'    => ['>', time()],
-        ];
-        return EEM_Ticket::instance()->count([$where]);
-    }
-
-
-    /**
-     * This returns whether there are any tickets on sale for this event.
-     *
-     * @return bool true = YES tickets on sale.
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function tickets_on_sale(): bool
-    {
-        return $this->countTicketsOnSale() > 0;
-    }
-
-
-    /**
-     * Gets the URL for viewing this event on the front-end. Overrides parent
-     * to check for an external URL first
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_permalink(): string
-    {
-        if ($this->external_url()) {
-            return $this->external_url();
-        }
-        return parent::get_permalink();
-    }
-
-
-    /**
-     * Gets the first term for 'espresso_event_categories' we can find
-     *
-     * @param array $query_params
-     * @return EE_Base_Class|EE_Term|null
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     */
-    public function first_event_category(array $query_params = []): ?EE_Term
-    {
-        $query_params[0]['Term_Taxonomy.taxonomy']     = 'espresso_event_categories';
-        $query_params[0]['Term_Taxonomy.Event.EVT_ID'] = $this->ID();
-        return EEM_Term::instance()->get_one($query_params);
-    }
-
-
-    /**
-     * Gets all terms for 'espresso_event_categories' we can find
-     *
-     * @param array $query_params
-     * @return EE_Base_Class[]|EE_Term[]
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_all_event_categories(array $query_params = []): array
-    {
-        $query_params[0]['Term_Taxonomy.taxonomy']     = 'espresso_event_categories';
-        $query_params[0]['Term_Taxonomy.Event.EVT_ID'] = $this->ID();
-        return EEM_Term::instance()->get_all($query_params);
-    }
-
-
-    /**
-     * Adds a question group to this event
-     *
-     * @param EE_Question_Group|int $question_group_id_or_obj
-     * @param bool                  $for_primary if true, the question group will be added for the primary
-     *                                           registrant, if false will be added for others. default: false
-     * @return EE_Base_Class|EE_Question_Group
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function add_question_group($question_group_id_or_obj, bool $for_primary = false): EE_Question_Group
-    {
-        // If the row already exists, it will be updated. If it doesn't, it will be inserted.
-        // That's in EE_HABTM_Relation::add_relation_to().
-        return $this->_add_relation_to(
-            $question_group_id_or_obj,
-            'Question_Group',
-            [
-                EEM_Event_Question_Group::instance()->fieldNameForContext($for_primary) => true,
-            ]
-        );
-    }
-
-
-    /**
-     * Removes a question group from the event
-     *
-     * @param EE_Question_Group|int $question_group_id_or_obj
-     * @param bool                  $for_primary if true, the question group will be removed from the primary
-     *                                           registrant, if false will be removed from others. default: false
-     * @return EE_Base_Class|EE_Question_Group|int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function remove_question_group($question_group_id_or_obj, bool $for_primary = false)
-    {
-        // If the question group is used for the other type (primary or additional)
-        // then just update it. If not, delete it outright.
-        $existing_relation = $this->get_first_related(
-            'Event_Question_Group',
-            [
-                [
-                    'QSG_ID' => EEM_Question_Group::instance()->ensure_is_ID($question_group_id_or_obj),
-                ],
-            ]
-        );
-        $field_to_update   = EEM_Event_Question_Group::instance()->fieldNameForContext($for_primary);
-        $other_field       = EEM_Event_Question_Group::instance()->fieldNameForContext(! $for_primary);
-        if ($existing_relation->get($other_field) === false) {
-            // Delete it. It's now no longer for primary or additional question groups.
-            return $this->_remove_relation_to($question_group_id_or_obj, 'Question_Group');
-        }
-        // Just update it. They'll still use this question group for the other category
-        $existing_relation->save(
-            [
-                $field_to_update => false,
-            ]
-        );
-        return $question_group_id_or_obj;
-    }
-
-
-    /**
-     * Gets all the question groups, ordering them by QSG_order ascending
-     *
-     * @param array $query_params
-     * @return EE_Base_Class[]|EE_Question_Group[]
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     */
-    public function question_groups(array $query_params = []): array
-    {
-        $query_params = ! empty($query_params) ? $query_params : ['order_by' => ['QSG_order' => 'ASC']];
-        return $this->get_many_related('Question_Group', $query_params);
-    }
-
-
-    /**
-     * Implementation for EEI_Has_Icon interface method.
-     *
-     * @return string
-     * @see EEI_Visual_Representation for comments
-     */
-    public function get_icon(): string
-    {
-        return '<span class="dashicons dashicons-flag"></span>';
-    }
-
-
-    /**
-     * Implementation for EEI_Admin_Links interface method.
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @see EEI_Admin_Links for comments
-     */
-    public function get_admin_details_link(): string
-    {
-        return $this->get_admin_edit_link();
-    }
-
-
-    /**
-     * Implementation for EEI_Admin_Links interface method.
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @see EEI_Admin_Links for comments
-     */
-    public function get_admin_edit_link(): string
-    {
-        return EEH_URL::add_query_args_and_nonce(
-            [
-                'page'   => 'espresso_events',
-                'action' => 'edit',
-                'post'   => $this->ID(),
-            ],
-            admin_url('admin.php')
-        );
-    }
-
-
-    /**
-     * Implementation for EEI_Admin_Links interface method.
-     *
-     * @return string
-     * @see EEI_Admin_Links for comments
-     */
-    public function get_admin_settings_link(): string
-    {
-        return EEH_URL::add_query_args_and_nonce(
-            [
-                'page'   => 'espresso_events',
-                'action' => 'default_event_settings',
-            ],
-            admin_url('admin.php')
-        );
-    }
-
-
-    /**
-     * Implementation for EEI_Admin_Links interface method.
-     *
-     * @return string
-     * @see EEI_Admin_Links for comments
-     */
-    public function get_admin_overview_link(): string
-    {
-        return EEH_URL::add_query_args_and_nonce(
-            [
-                'page'   => 'espresso_events',
-                'action' => 'default',
-            ],
-            admin_url('admin.php')
-        );
-    }
-
-
-    /**
-     * @return string|null
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function registrationFormUuid(): ?string
-    {
-        return $this->get('FSC_UUID') ?? '';
-    }
-
-
-    /**
-     * Gets all the form sections for this event
-     *
-     * @return EE_Base_Class[]|EE_Form_Section[]
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function registrationForm(): array
-    {
-        $FSC_UUID = $this->registrationFormUuid();
-
-        if (empty($FSC_UUID)) {
-            return [];
-        }
-
-        return EEM_Form_Section::instance()->get_all(
-            [
-                [
-                    'OR' => [
-                        'FSC_UUID'      => $FSC_UUID, // top level form
-                        'FSC_belongsTo' => $FSC_UUID, // child form sections
-                    ],
-                ],
-                'order_by' => ['FSC_order' => 'ASC'],
-            ]
-        );
-    }
-
-
-    /**
-     * @param string $UUID
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function setRegistrationFormUuid(string $UUID): void
-    {
-        if (! Cuid::isCuid($UUID)) {
-            throw new InvalidArgumentException(
-                sprintf(
-                /* translators: 1: UUID value, 2: UUID generator function. */
-                    esc_html__(
-                        'The supplied UUID "%1$s" is invalid or missing. Please use %2$s to generate a valid one.',
-                        'event_espresso'
-                    ),
-                    $UUID,
-                    '`Cuid::cuid()`'
-                )
-            );
-        }
-        $this->set('FSC_UUID', $UUID);
-    }
-
-
-    /**
-     * Get visibility status of event
-     *
-     * @param bool $hide_public
-     * @return string
-     */
-    public function get_visibility_status(bool $hide_public = true): string
-    {
-        if ($this->status() === 'private') {
-            return esc_html__('Private', 'event_espresso');
-        }
-        if (! empty($this->wp_post()->post_password)) {
-            return esc_html__('Password Protected', 'event_espresso');
-        }
-        if (! $hide_public) {
-            return esc_html__('Public', 'event_espresso');
-        }
-
-        return '';
-    }
+		if ($echo) {
+			echo wp_kses($status, AllowedTags::getAllowedTags());
+			return '';
+		}
+		return $status;
+	}
+
+
+	/**
+	 * @return bool|int
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_number_of_tickets_sold()
+	{
+		$tkt_sold = 0;
+		if (! $this->ID()) {
+			return 0;
+		}
+		$datetimes = $this->datetimes();
+		foreach ($datetimes as $datetime) {
+			if ($datetime instanceof EE_Datetime) {
+				$tkt_sold += $datetime->sold();
+			}
+		}
+		return $tkt_sold;
+	}
+
+
+	/**
+	 * This just returns a count of all the registrations for this event
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_count_of_all_registrations(): int
+	{
+		return EEM_Event::instance()->count_related($this, 'Registration');
+	}
+
+
+	/**
+	 * This returns the ticket with the earliest start time that is
+	 * available for this event (across all datetimes attached to the event)
+	 *
+	 * @return EE_Base_Class|EE_Ticket|null
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_ticket_with_earliest_start_time()
+	{
+		$where['Datetime.EVT_ID'] = $this->ID();
+		$query_params             = [$where, 'order_by' => ['TKT_start_date' => 'ASC']];
+		return EE_Registry::instance()->load_model('Ticket')->get_one($query_params);
+	}
+
+
+	/**
+	 * This returns the ticket with the latest end time that is available
+	 * for this event (across all datetimes attached to the event)
+	 *
+	 * @return EE_Base_Class|EE_Ticket|null
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_ticket_with_latest_end_time()
+	{
+		$where['Datetime.EVT_ID'] = $this->ID();
+		$query_params             = [$where, 'order_by' => ['TKT_end_date' => 'DESC']];
+		return EE_Registry::instance()->load_model('Ticket')->get_one($query_params);
+	}
+
+
+	/**
+	 * This returns the number of different ticket types currently on sale for this event.
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function countTicketsOnSale(): int
+	{
+		$where = [
+			'Datetime.EVT_ID' => $this->ID(),
+			'TKT_start_date'  => ['<', time()],
+			'TKT_end_date'    => ['>', time()],
+		];
+		return EEM_Ticket::instance()->count([$where]);
+	}
+
+
+	/**
+	 * This returns whether there are any tickets on sale for this event.
+	 *
+	 * @return bool true = YES tickets on sale.
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function tickets_on_sale(): bool
+	{
+		return $this->countTicketsOnSale() > 0;
+	}
+
+
+	/**
+	 * Gets the URL for viewing this event on the front-end. Overrides parent
+	 * to check for an external URL first
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_permalink(): string
+	{
+		if ($this->external_url()) {
+			return $this->external_url();
+		}
+		return parent::get_permalink();
+	}
+
+
+	/**
+	 * Gets the first term for 'espresso_event_categories' we can find
+	 *
+	 * @param array $query_params
+	 * @return EE_Base_Class|EE_Term|null
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 */
+	public function first_event_category(array $query_params = []): ?EE_Term
+	{
+		$query_params[0]['Term_Taxonomy.taxonomy']     = 'espresso_event_categories';
+		$query_params[0]['Term_Taxonomy.Event.EVT_ID'] = $this->ID();
+		return EEM_Term::instance()->get_one($query_params);
+	}
+
+
+	/**
+	 * Gets all terms for 'espresso_event_categories' we can find
+	 *
+	 * @param array $query_params
+	 * @return EE_Base_Class[]|EE_Term[]
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_all_event_categories(array $query_params = []): array
+	{
+		$query_params[0]['Term_Taxonomy.taxonomy']     = 'espresso_event_categories';
+		$query_params[0]['Term_Taxonomy.Event.EVT_ID'] = $this->ID();
+		return EEM_Term::instance()->get_all($query_params);
+	}
+
+
+	/**
+	 * Adds a question group to this event
+	 *
+	 * @param EE_Question_Group|int $question_group_id_or_obj
+	 * @param bool                  $for_primary if true, the question group will be added for the primary
+	 *                                           registrant, if false will be added for others. default: false
+	 * @return EE_Base_Class|EE_Question_Group
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function add_question_group($question_group_id_or_obj, bool $for_primary = false): EE_Question_Group
+	{
+		// If the row already exists, it will be updated. If it doesn't, it will be inserted.
+		// That's in EE_HABTM_Relation::add_relation_to().
+		return $this->_add_relation_to(
+			$question_group_id_or_obj,
+			'Question_Group',
+			[
+				EEM_Event_Question_Group::instance()->fieldNameForContext($for_primary) => true,
+			]
+		);
+	}
+
+
+	/**
+	 * Removes a question group from the event
+	 *
+	 * @param EE_Question_Group|int $question_group_id_or_obj
+	 * @param bool                  $for_primary if true, the question group will be removed from the primary
+	 *                                           registrant, if false will be removed from others. default: false
+	 * @return EE_Base_Class|EE_Question_Group|int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function remove_question_group($question_group_id_or_obj, bool $for_primary = false)
+	{
+		// If the question group is used for the other type (primary or additional)
+		// then just update it. If not, delete it outright.
+		$existing_relation = $this->get_first_related(
+			'Event_Question_Group',
+			[
+				[
+					'QSG_ID' => EEM_Question_Group::instance()->ensure_is_ID($question_group_id_or_obj),
+				],
+			]
+		);
+		$field_to_update   = EEM_Event_Question_Group::instance()->fieldNameForContext($for_primary);
+		$other_field       = EEM_Event_Question_Group::instance()->fieldNameForContext(! $for_primary);
+		if ($existing_relation->get($other_field) === false) {
+			// Delete it. It's now no longer for primary or additional question groups.
+			return $this->_remove_relation_to($question_group_id_or_obj, 'Question_Group');
+		}
+		// Just update it. They'll still use this question group for the other category
+		$existing_relation->save(
+			[
+				$field_to_update => false,
+			]
+		);
+		return $question_group_id_or_obj;
+	}
+
+
+	/**
+	 * Gets all the question groups, ordering them by QSG_order ascending
+	 *
+	 * @param array $query_params
+	 * @return EE_Base_Class[]|EE_Question_Group[]
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @see https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 */
+	public function question_groups(array $query_params = []): array
+	{
+		$query_params = ! empty($query_params) ? $query_params : ['order_by' => ['QSG_order' => 'ASC']];
+		return $this->get_many_related('Question_Group', $query_params);
+	}
+
+
+	/**
+	 * Implementation for EEI_Has_Icon interface method.
+	 *
+	 * @return string
+	 * @see EEI_Visual_Representation for comments
+	 */
+	public function get_icon(): string
+	{
+		return '<span class="dashicons dashicons-flag"></span>';
+	}
+
+
+	/**
+	 * Implementation for EEI_Admin_Links interface method.
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @see EEI_Admin_Links for comments
+	 */
+	public function get_admin_details_link(): string
+	{
+		return $this->get_admin_edit_link();
+	}
+
+
+	/**
+	 * Implementation for EEI_Admin_Links interface method.
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @see EEI_Admin_Links for comments
+	 */
+	public function get_admin_edit_link(): string
+	{
+		return EEH_URL::add_query_args_and_nonce(
+			[
+				'page'   => 'espresso_events',
+				'action' => 'edit',
+				'post'   => $this->ID(),
+			],
+			admin_url('admin.php')
+		);
+	}
+
+
+	/**
+	 * Implementation for EEI_Admin_Links interface method.
+	 *
+	 * @return string
+	 * @see EEI_Admin_Links for comments
+	 */
+	public function get_admin_settings_link(): string
+	{
+		return EEH_URL::add_query_args_and_nonce(
+			[
+				'page'   => 'espresso_events',
+				'action' => 'default_event_settings',
+			],
+			admin_url('admin.php')
+		);
+	}
+
+
+	/**
+	 * Implementation for EEI_Admin_Links interface method.
+	 *
+	 * @return string
+	 * @see EEI_Admin_Links for comments
+	 */
+	public function get_admin_overview_link(): string
+	{
+		return EEH_URL::add_query_args_and_nonce(
+			[
+				'page'   => 'espresso_events',
+				'action' => 'default',
+			],
+			admin_url('admin.php')
+		);
+	}
+
+
+	/**
+	 * @return string|null
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function registrationFormUuid(): ?string
+	{
+		return $this->get('FSC_UUID') ?? '';
+	}
+
+
+	/**
+	 * Gets all the form sections for this event
+	 *
+	 * @return EE_Base_Class[]|EE_Form_Section[]
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function registrationForm(): array
+	{
+		$FSC_UUID = $this->registrationFormUuid();
+
+		if (empty($FSC_UUID)) {
+			return [];
+		}
+
+		return EEM_Form_Section::instance()->get_all(
+			[
+				[
+					'OR' => [
+						'FSC_UUID'      => $FSC_UUID, // top level form
+						'FSC_belongsTo' => $FSC_UUID, // child form sections
+					],
+				],
+				'order_by' => ['FSC_order' => 'ASC'],
+			]
+		);
+	}
+
+
+	/**
+	 * @param string $UUID
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function setRegistrationFormUuid(string $UUID): void
+	{
+		if (! Cuid::isCuid($UUID)) {
+			throw new InvalidArgumentException(
+				sprintf(
+				/* translators: 1: UUID value, 2: UUID generator function. */
+					esc_html__(
+						'The supplied UUID "%1$s" is invalid or missing. Please use %2$s to generate a valid one.',
+						'event_espresso'
+					),
+					$UUID,
+					'`Cuid::cuid()`'
+				)
+			);
+		}
+		$this->set('FSC_UUID', $UUID);
+	}
+
+
+	/**
+	 * Get visibility status of event
+	 *
+	 * @param bool $hide_public
+	 * @return string
+	 */
+	public function get_visibility_status(bool $hide_public = true): string
+	{
+		if ($this->status() === 'private') {
+			return esc_html__('Private', 'event_espresso');
+		}
+		if (! empty($this->wp_post()->post_password)) {
+			return esc_html__('Password Protected', 'event_espresso');
+		}
+		if (! $hide_public) {
+			return esc_html__('Public', 'event_espresso');
+		}
+
+		return '';
+	}
 }

core/db_classes/EE_Registration.class.php

Indentation +2592 added lines, -2592 removed lines

@@ -19,2596 +19,2596 @@
  */
 class EE_Registration extends EE_Soft_Delete_Base_Class implements EEI_Registration, EEI_Admin_Links
 {
-    /**
-     * Used to reference when a registration has never been checked in.
-     *
-     * @deprecated use \EE_Checkin::status_checked_never instead
-     * @type int
-     */
-    const checkin_status_never = 2;
-
-    /**
-     * Used to reference when a registration has been checked in.
-     *
-     * @deprecated use \EE_Checkin::status_checked_in instead
-     * @type int
-     */
-    const checkin_status_in = 1;
-
-    /**
-     * Used to reference when a registration has been checked out.
-     *
-     * @deprecated use \EE_Checkin::status_checked_out instead
-     * @type int
-     */
-    const checkin_status_out = 0;
-
-    /**
-     * extra meta key for tracking reg status os trashed registrations
-     *
-     * @type string
-     */
-    const PRE_TRASH_REG_STATUS_KEY = 'pre_trash_registration_status';
-
-    /**
-     * extra meta key for tracking if registration has reserved ticket
-     *
-     * @type string
-     */
-    const HAS_RESERVED_TICKET_KEY = 'has_reserved_ticket';
-
-
-    /**
-     * @param array  $props_n_values          incoming values
-     * @param string $timezone                incoming timezone (if not set the timezone set for the website will be
-     *                                        used.)
-     * @param array  $date_formats            incoming date_formats in an array where the first value is the
-     *                                        date_format and the second value is the time format
-     * @return EE_Registration
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function new_instance($props_n_values = [], $timezone = '', $date_formats = [])
-    {
-        $has_object = parent::_check_for_object($props_n_values, __CLASS__, $timezone, $date_formats);
-        return $has_object
-            ?: new self($props_n_values, false, $timezone, $date_formats);
-    }
-
-
-    /**
-     * @param array  $props_n_values  incoming values from the database
-     * @param string $timezone        incoming timezone as set by the model.  If not set the timezone for
-     *                                the website will be used.
-     * @return EE_Registration
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function new_instance_from_db($props_n_values = [], $timezone = '')
-    {
-        return new self($props_n_values, true, $timezone);
-    }
-
-
-    /**
-     *        Set Event ID
-     *
-     * @param int $EVT_ID Event ID
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function set_event($EVT_ID = 0)
-    {
-        $this->set('EVT_ID', $EVT_ID);
-    }
-
-
-    /**
-     * Overrides parent set() method so that all calls to set( 'REG_code', $REG_code ) OR set( 'STS_ID', $STS_ID ) can
-     * be routed to internal methods
-     *
-     * @param string $field_name
-     * @param mixed  $field_value
-     * @param bool   $use_default
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function set($field_name, $field_value, $use_default = false)
-    {
-        switch ($field_name) {
-            case 'REG_code':
-                if (! empty($field_value) && ! $this->reg_code()) {
-                    $this->set_reg_code($field_value, $use_default);
-                }
-                break;
-            case 'STS_ID':
-                $this->set_status((string) $field_value, $use_default);
-                break;
-            default:
-                parent::set($field_name, $field_value, $use_default);
-        }
-    }
-
-
-    /**
-     * Set Status ID
-     * updates the registration status and ALSO...
-     * calls reserve_registration_space() if the reg status changes TO approved from any other reg status
-     * calls release_registration_space() if the reg status changes FROM approved to any other reg status
-     *
-     * @param string                $new_STS_ID
-     * @param boolean               $use_default
-     * @param ContextInterface|null $context
-     * @return bool
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function set_status(
-        string $new_STS_ID = '',
-        bool $use_default = false,
-        ?ContextInterface $context = null
-    ): bool {
-        // get current REG_Status
-        $old_STS_ID = $this->status_ID();
-        $new_STS_ID = (string) apply_filters(
-            'AFEE__EE_Registration__set_status__new_STS_ID',
-            $new_STS_ID,
-            $context,
-            $this
-        );
-        // it's still good to allow the parent set method to have a say
-        parent::set('STS_ID', (! empty($new_STS_ID) ? $new_STS_ID : null), $use_default);
-        // if status has changed
-        if (
-            $old_STS_ID !== $new_STS_ID // and that status has actually changed
-            && ! empty($old_STS_ID) // and that old status is actually set
-            && ! empty($new_STS_ID) // as well as the new status
-            && $this->ID() // ensure registration is in the db
-        ) {
-            // THEN handle other changes that occur when reg status changes
-            // TO approved
-            if ($new_STS_ID === RegStatus::APPROVED) {
-                // reserve a space by incrementing ticket and datetime sold values
-                $this->reserveRegistrationSpace();
-                do_action('AHEE__EE_Registration__set_status__to_approved', $this, $old_STS_ID, $new_STS_ID, $context);
-                // OR FROM  approved
-            } elseif ($old_STS_ID === RegStatus::APPROVED) {
-                // release a space by decrementing ticket and datetime sold values
-                $this->releaseRegistrationSpace();
-                do_action(
-                    'AHEE__EE_Registration__set_status__from_approved',
-                    $this,
-                    $old_STS_ID,
-                    $new_STS_ID,
-                    $context
-                );
-            }
-            $this->updateIfCanceledOrReinstated($new_STS_ID, $old_STS_ID, $context);
-            if ($this->statusChangeUpdatesTransaction($context)) {
-                $this->updateTransactionAfterStatusChange();
-            }
-            do_action('AHEE__EE_Registration__set_status__after_update', $this, $old_STS_ID, $new_STS_ID, $context);
-        }
-        return ! empty($new_STS_ID);
-    }
-
-
-    /**
-     * update REGs and TXN when cancelled or declined registrations involved
-     *
-     * @param string                $new_STS_ID
-     * @param string                $old_STS_ID
-     * @param ContextInterface|null $context
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     */
-    private function updateIfCanceledOrReinstated($new_STS_ID, $old_STS_ID, ?ContextInterface $context = null)
-    {
-        // these reg statuses should not be considered in any calculations involving monies owing
-        $closed_reg_statuses = EEM_Registration::closed_reg_statuses();
-        // true if registration has been cancelled or declined
-        $this->updateIfCanceled(
-            $closed_reg_statuses,
-            $new_STS_ID,
-            $old_STS_ID,
-            $context
-        );
-        $this->updateIfReinstated(
-            $closed_reg_statuses,
-            $new_STS_ID,
-            $old_STS_ID,
-            $context
-        );
-    }
-
-
-    /**
-     * update REGs and TXN when cancelled or declined registrations involved
-     *
-     * @param array                 $closed_reg_statuses
-     * @param string                $new_STS_ID
-     * @param string                $old_STS_ID
-     * @param ContextInterface|null $context
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     */
-    private function updateIfCanceled(
-        array $closed_reg_statuses,
-        $new_STS_ID,
-        $old_STS_ID,
-        ?ContextInterface $context = null
-    ) {
-        // true if registration has been cancelled or declined
-        if (
-            in_array($new_STS_ID, $closed_reg_statuses, true)
-            && ! in_array($old_STS_ID, $closed_reg_statuses, true)
-        ) {
-            /** @type EE_Registration_Processor $registration_processor */
-            $registration_processor = EE_Registry::instance()->load_class('Registration_Processor');
-            /** @type EE_Transaction_Processor $transaction_processor */
-            $transaction_processor = EE_Registry::instance()->load_class('Transaction_Processor');
-            // cancelled or declined registration
-            $registration_processor->update_registration_after_being_canceled_or_declined(
-                $this,
-                $closed_reg_statuses
-            );
-            $transaction_processor->update_transaction_after_canceled_or_declined_registration(
-                $this,
-                $closed_reg_statuses,
-                false
-            );
-            do_action(
-                'AHEE__EE_Registration__set_status__canceled_or_declined',
-                $this,
-                $old_STS_ID,
-                $new_STS_ID,
-                $context
-            );
-        }
-    }
-
-
-    /**
-     * update REGs and TXN when cancelled or declined registrations involved
-     *
-     * @param array                 $closed_reg_statuses
-     * @param string                $new_STS_ID
-     * @param string                $old_STS_ID
-     * @param ContextInterface|null $context
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     */
-    private function updateIfReinstated(
-        array $closed_reg_statuses,
-        $new_STS_ID,
-        $old_STS_ID,
-        ?ContextInterface $context = null
-    ) {
-        // true if reinstating cancelled or declined registration
-        if (
-            in_array($old_STS_ID, $closed_reg_statuses, true)
-            && ! in_array($new_STS_ID, $closed_reg_statuses, true)
-        ) {
-            /** @type EE_Registration_Processor $registration_processor */
-            $registration_processor = EE_Registry::instance()->load_class('Registration_Processor');
-            /** @type EE_Transaction_Processor $transaction_processor */
-            $transaction_processor = EE_Registry::instance()->load_class('Transaction_Processor');
-            // reinstating cancelled or declined registration
-            $registration_processor->update_canceled_or_declined_registration_after_being_reinstated(
-                $this,
-                $closed_reg_statuses
-            );
-            $transaction_processor->update_transaction_after_reinstating_canceled_registration(
-                $this,
-                $closed_reg_statuses,
-                false
-            );
-            do_action(
-                'AHEE__EE_Registration__set_status__after_reinstated',
-                $this,
-                $old_STS_ID,
-                $new_STS_ID,
-                $context
-            );
-        }
-    }
-
-
-    /**
-     * @param ContextInterface|null $context
-     * @return bool
-     */
-    private function statusChangeUpdatesTransaction(?ContextInterface $context = null)
-    {
-        $contexts_that_do_not_update_transaction = (array) apply_filters(
-            'AHEE__EE_Registration__statusChangeUpdatesTransaction__contexts_that_do_not_update_transaction',
-            ['spco_reg_step_attendee_information_process_registrations'],
-            $context,
-            $this
-        );
-        return ! (
-            $context instanceof ContextInterface
-            && in_array($context->slug(), $contexts_that_do_not_update_transaction, true)
-        );
-    }
-
-
-    /**
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     */
-    private function updateTransactionAfterStatusChange()
-    {
-        /** @type EE_Transaction_Payments $transaction_payments */
-        $transaction_payments = EE_Registry::instance()->load_class('Transaction_Payments');
-        $transaction_payments->recalculate_transaction_total($this->transaction(), false);
-        $this->transaction()->update_status_based_on_total_paid();
-    }
-
-
-    /**
-     * get Status ID
-     *
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function status_ID()
-    {
-        return $this->get('STS_ID');
-    }
-
-
-    /**
-     * Gets the ticket this registration is for
-     *
-     * @param boolean $include_archived whether to include archived tickets or not.
-     * @return EE_Ticket|EE_Base_Class
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function ticket($include_archived = true)
-    {
-        return EEM_Ticket::instance()->get_one_by_ID($this->ticket_ID());
-    }
-
-
-    /**
-     * Gets the event this registration is for
-     *
-     * @return EE_Event
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function event(): EE_Event
-    {
-        $event = $this->event_obj();
-        if (! $event instanceof EE_Event) {
-            throw new EntityNotFoundException('Event ID', $this->event_ID());
-        }
-        return $event;
-    }
-
-
-    /**
-     * Gets the "author" of the registration.  Note that for the purposes of registrations, the author will correspond
-     * with the author of the event this registration is for.
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @since 4.5.0
-     */
-    public function wp_user(): int
-    {
-        return $this->event()->wp_user();
-    }
-
-
-    /**
-     * increments this registration's related ticket sold and corresponding datetime sold values
-     *
-     * @return void
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws UnexpectedEntityException
-     */
-    private function reserveRegistrationSpace()
-    {
-        // reserved ticket and datetime counts will be decremented as sold counts are incremented
-        // so stop tracking that this reg has a ticket reserved
-        $this->release_reserved_ticket(false, "REG: {$this->ID()} (ln:" . __LINE__ . ')');
-        $ticket = $this->ticket();
-        $ticket->increaseSold();
-        // possibly set event status to sold out
-        $this->event()->perform_sold_out_status_check();
-    }
-
-
-    /**
-     * decrements (subtracts) this registration's related ticket sold and corresponding datetime sold values
-     *
-     * @return void
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws UnexpectedEntityException
-     */
-    private function releaseRegistrationSpace()
-    {
-        $ticket = $this->ticket();
-        $ticket->decreaseSold();
-        // possibly change event status from sold out back to previous status
-        $this->event()->perform_sold_out_status_check();
-    }
-
-
-    /**
-     * tracks this registration's ticket reservation in extra meta
-     * and can increment related ticket reserved and corresponding datetime reserved values
-     *
-     * @param bool   $update_ticket if true, will increment ticket and datetime reserved count
-     * @param string $source
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function reserve_ticket($update_ticket = false, $source = 'unknown')
-    {
-        // only reserve ticket if space is not currently reserved
-        if ((bool) $this->get_extra_meta(EE_Registration::HAS_RESERVED_TICKET_KEY, true) !== true) {
-            $reserved = $this->update_extra_meta(EE_Registration::HAS_RESERVED_TICKET_KEY, true);
-            if ($reserved && $update_ticket) {
-                $ticket = $this->ticket();
-                $ticket->increaseReserved(1, "REG: {$this->ID()} (ln:" . __LINE__ . ')');
-                $this->update_extra_meta('reserve_ticket', "{$this->ticket_ID()} from {$source}");
-                $ticket->save();
-            }
-        }
-    }
-
-
-    /**
-     * stops tracking this registration's ticket reservation in extra meta
-     * decrements (subtracts) related ticket reserved and corresponding datetime reserved values
-     *
-     * @param bool   $update_ticket if true, will decrement ticket and datetime reserved count
-     * @param string $source
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function release_reserved_ticket($update_ticket = false, $source = 'unknown')
-    {
-        // only release ticket if space is currently reserved
-        if ((bool) $this->get_extra_meta(EE_Registration::HAS_RESERVED_TICKET_KEY, true) === true) {
-            $reserved = $this->update_extra_meta(EE_Registration::HAS_RESERVED_TICKET_KEY, false);
-            if ($reserved && $update_ticket) {
-                $ticket = $this->ticket();
-                $ticket->decreaseReserved(1, true, "REG: {$this->ID()} (ln:" . __LINE__ . ')');
-                $this->update_extra_meta('release_reserved_ticket', "{$this->ticket_ID()} from {$source}");
-            }
-        }
-    }
-
-
-    /**
-     * Set Attendee ID
-     *
-     * @param int $ATT_ID Attendee ID
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function set_attendee_id($ATT_ID = 0)
-    {
-        $this->set('ATT_ID', $ATT_ID);
-    }
-
-
-    /**
-     *        Set Transaction ID
-     *
-     * @param int $TXN_ID Transaction ID
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function set_transaction_id($TXN_ID = 0)
-    {
-        $this->set('TXN_ID', $TXN_ID);
-    }
-
-
-    /**
-     *        Set Session
-     *
-     * @param string $REG_session PHP Session ID
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function set_session($REG_session = '')
-    {
-        $this->set('REG_session', $REG_session);
-    }
-
-
-    /**
-     *        Set Registration URL Link
-     *
-     * @param string $REG_url_link Registration URL Link
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function set_reg_url_link($REG_url_link = '')
-    {
-        $this->set('REG_url_link', $REG_url_link);
-    }
-
-
-    /**
-     *        Set Attendee Counter
-     *
-     * @param int $REG_count Primary Attendee
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function set_count($REG_count = 1)
-    {
-        $this->set('REG_count', $REG_count);
-    }
-
-
-    /**
-     *        Set Group Size
-     *
-     * @param boolean $REG_group_size Group Registration
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function set_group_size($REG_group_size = false)
-    {
-        $this->set('REG_group_size', $REG_group_size);
-    }
-
-
-    /**
-     *    is_not_approved -  convenience method that returns TRUE if REG status ID ==
-     *    RegStatus::AWAITING_REVIEW
-     *
-     * @return        boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_not_approved()
-    {
-        return $this->status_ID() === RegStatus::AWAITING_REVIEW;
-    }
-
-
-    /**
-     *    is_pending_payment -  convenience method that returns TRUE if REG status ID ==
-     *    RegStatus::PENDING_PAYMENT
-     *
-     * @return        boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_pending_payment()
-    {
-        return $this->status_ID() === RegStatus::PENDING_PAYMENT;
-    }
-
-
-    /**
-     *    is_approved -  convenience method that returns TRUE if REG status ID == RegStatus::APPROVED
-     *
-     * @return        boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_approved()
-    {
-        return $this->status_ID() === RegStatus::APPROVED;
-    }
-
-
-    /**
-     *    is_cancelled -  convenience method that returns TRUE if REG status ID == RegStatus::CANCELLED
-     *
-     * @return        boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_cancelled()
-    {
-        return $this->status_ID() === RegStatus::CANCELLED;
-    }
-
-
-    /**
-     *    is_declined -  convenience method that returns TRUE if REG status ID == RegStatus::DECLINED
-     *
-     * @return        boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_declined()
-    {
-        return $this->status_ID() === RegStatus::DECLINED;
-    }
-
-
-    /**
-     *    is_incomplete -  convenience method that returns TRUE if REG status ID ==
-     *    RegStatus::INCOMPLETE
-     *
-     * @return        boolean
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_incomplete()
-    {
-        return $this->status_ID() === RegStatus::INCOMPLETE;
-    }
-
-
-    /**
-     *        Set Registration Date
-     *
-     * @param mixed ( int or string ) $REG_date Registration Date - Unix timestamp or string representation of
-     *                                                 Date
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function set_reg_date($REG_date = false)
-    {
-        $this->set('REG_date', $REG_date);
-    }
-
-
-    /**
-     *    Set final price owing for this registration after all ticket/price modifications
-     *
-     * @param float $REG_final_price
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function set_final_price($REG_final_price = 0.00)
-    {
-        $this->set('REG_final_price', $REG_final_price);
-    }
-
-
-    /**
-     *    Set amount paid towards this registration's final price
-     *
-     * @param float|int|string $REG_paid
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function set_paid($REG_paid = 0.00)
-    {
-        $this->set('REG_paid', (float) $REG_paid);
-    }
-
-
-    /**
-     *        Attendee Is Going
-     *
-     * @param boolean $REG_att_is_going Attendee Is Going
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function set_att_is_going($REG_att_is_going = false)
-    {
-        $this->set('REG_att_is_going', $REG_att_is_going);
-    }
-
-
-    /**
-     * Gets the related attendee
-     *
-     * @return EE_Attendee|EE_Base_Class
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function attendee()
-    {
-        return EEM_Attendee::instance()->get_one_by_ID($this->attendee_ID());
-    }
-
-
-    /**
-     * Gets the name of the attendee.
-     *
-     * @param bool $apply_html_entities set to true if you want to use HTML entities.
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @since 4.10.12.p
-     */
-    public function attendeeName($apply_html_entities = false)
-    {
-        $attendee = $this->attendee();
-        if ($attendee instanceof EE_Attendee) {
-            $attendee_name = $attendee->full_name($apply_html_entities);
-        } else {
-            $attendee_name = esc_html__('Unknown', 'event_espresso');
-        }
-        return $attendee_name;
-    }
-
-
-    /**
-     *        get Event ID
-     */
-    public function event_ID()
-    {
-        return $this->get('EVT_ID');
-    }
-
-
-    /**
-     *        get Event ID
-     */
-    public function event_name()
-    {
-        $event = $this->event_obj();
-        if ($event) {
-            return $event->name();
-        } else {
-            return null;
-        }
-    }
-
-
-    /**
-     * Fetches the event this registration is for
-     *
-     * @return EE_Base_Class|EE_Event
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function event_obj()
-    {
-        return EEM_Event::instance()->get_one_by_ID($this->event_ID());
-    }
-
-
-    /**
-     *        get Attendee ID
-     */
-    public function attendee_ID()
-    {
-        return $this->get('ATT_ID');
-    }
-
-
-    /**
-     *        get PHP Session ID
-     */
-    public function session_ID()
-    {
-        return $this->get('REG_session');
-    }
-
-
-    /**
-     * Gets the string which represents the URL trigger for the receipt template in the message template system.
-     *
-     * @param string $messenger 'pdf' or 'html'.  Default 'html'.
-     * @return string
-     * @throws DomainException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function receipt_url($messenger = 'html')
-    {
-        return apply_filters('FHEE__EE_Registration__receipt_url__receipt_url', '', $this, $messenger, 'receipt');
-    }
-
-
-    /**
-     * Gets the string which represents the URL trigger for the invoice template in the message template system.
-     *
-     * @param string $messenger 'pdf' or 'html'.  Default 'html'.
-     * @return string
-     * @throws DomainException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function invoice_url($messenger = 'html')
-    {
-        return apply_filters('FHEE__EE_Registration__invoice_url__invoice_url', '', $this, $messenger, 'invoice');
-    }
-
-
-    /**
-     * get Registration URL Link
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function reg_url_link()
-    {
-        return (string) $this->get('REG_url_link');
-    }
-
-
-    /**
-     * Echoes out invoice_url()
-     *
-     * @param string $type 'download','launch', or 'html' (default is 'launch')
-     * @return void
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function e_invoice_url($type = 'launch')
-    {
-        echo esc_url_raw($this->invoice_url($type));
-    }
-
-
-    /**
-     * Echoes out payment_overview_url
-     */
-    public function e_payment_overview_url()
-    {
-        echo esc_url_raw($this->payment_overview_url());
-    }
-
-
-    /**
-     * Gets the URL for the checkout payment options reg step
-     * with this registration's REG_url_link added as a query parameter
-     *
-     * @param bool $clear_session Set to true when you want to clear the session on revisiting the
-     *                            payment overview url.
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function payment_overview_url($clear_session = false)
-    {
-        return add_query_arg(
-            (array) apply_filters(
-                'FHEE__EE_Registration__payment_overview_url__query_args',
-                [
-                    'e_reg_url_link' => $this->reg_url_link(),
-                    'step'           => 'payment_options',
-                    'revisit'        => true,
-                    'clear_session'  => (bool) $clear_session,
-                ],
-                $this
-            ),
-            EE_Registry::instance()->CFG->core->reg_page_url()
-        );
-    }
-
-
-    /**
-     * Gets the URL for the checkout attendee information reg step
-     * with this registration's REG_url_link added as a query parameter
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function edit_attendee_information_url()
-    {
-        return add_query_arg(
-            (array) apply_filters(
-                'FHEE__EE_Registration__edit_attendee_information_url__query_args',
-                [
-                    'e_reg_url_link' => $this->reg_url_link(),
-                    'step'           => 'attendee_information',
-                    'revisit'        => true,
-                ],
-                $this
-            ),
-            EE_Registry::instance()->CFG->core->reg_page_url()
-        );
-    }
-
-
-    /**
-     * Simply generates and returns the appropriate admin_url link to edit this registration
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_admin_edit_url()
-    {
-        return EEH_URL::add_query_args_and_nonce(
-            [
-                'page'    => 'espresso_registrations',
-                'action'  => 'view_registration',
-                '_REG_ID' => $this->ID(),
-            ],
-            admin_url('admin.php')
-        );
-    }
-
-
-    /**
-     * is_primary_registrant?
-     *
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_primary_registrant()
-    {
-        return (int) $this->get('REG_count') === 1;
-    }
-
-
-    /**
-     * This returns the primary registration object for this registration group (which may be this object).
-     *
-     * @return EE_Registration
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_primary_registration()
-    {
-        if ($this->is_primary_registrant()) {
-            return $this;
-        }
-
-        // k reg_count !== 1 so let's get the EE_Registration object matching this txn_id and reg_count == 1
-        /** @var EE_Registration $primary_registrant */
-        $primary_registrant = EEM_Registration::instance()->get_one(
-            [
-                [
-                    'TXN_ID'    => $this->transaction_ID(),
-                    'REG_count' => 1,
-                ],
-            ]
-        );
-        return $primary_registrant;
-    }
-
-
-    /**
-     * get  Attendee Number
-     *
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function count()
-    {
-        return $this->get('REG_count');
-    }
-
-
-    /**
-     * get Group Size
-     *
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function group_size()
-    {
-        return $this->get('REG_group_size');
-    }
-
-
-    /**
-     * get Registration Date
-     *
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function date()
-    {
-        return $this->get('REG_date');
-    }
-
-
-    /**
-     * gets a pretty date
-     *
-     * @param string $date_format
-     * @param string $time_format
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function pretty_date($date_format = null, $time_format = null)
-    {
-        return $this->get_datetime('REG_date', $date_format, $time_format);
-    }
-
-
-    /**
-     * final_price
-     * the registration's share of the transaction total, so that the
-     * sum of all the transaction's REG_final_prices equal the transaction's total
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function final_price(): float
-    {
-        return (float) $this->get('REG_final_price');
-    }
-
-
-    /**
-     * pretty_final_price
-     *  final price as formatted string, with correct decimal places and currency symbol
-     *
-     * @param string|null $schema
-     *      Schemas:
-     *      'localized_float': "3,023.00"
-     *      'no_currency_code': "$3,023.00"
-     *      null: "$3,023.00<span>USD</span>"
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function pretty_final_price(?string $schema = null)
-    {
-        return $this->get_pretty('REG_final_price', $schema);
-    }
-
-
-    /**
-     * get paid (yeah)
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function paid(): float
-    {
-        return (float) $this->get('REG_paid');
-    }
-
-
-    /**
-     * pretty_paid
-     *
-     * @param string|null $schema
-     *      Schemas:
-     *      'localized_float': "3,023.00"
-     *      'no_currency_code': "$3,023.00"
-     *      null: "$3,023.00<span>USD</span>"
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function pretty_paid(?string $schema = null)
-    {
-        return $this->get_pretty('REG_paid', $schema);
-    }
-
-
-    /**
-     * owes_monies_and_can_pay
-     * whether this registration has monies owing and it's' status allows payment
-     *
-     * @param array $requires_payment list of registration statuses that allow a registrant to make a payment
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function owes_monies_and_can_pay(array $requires_payment = []): bool
-    {
-        // these reg statuses require payment (if event is not free)
-        $requires_payment = ! empty($requires_payment)
-            ? $requires_payment
-            : EEM_Registration::reg_statuses_that_allow_payment();
-        if (
-            $this->final_price() !== 0.0 &&
-            $this->final_price() !== $this->paid() &&
-            in_array($this->status_ID(), $requires_payment)
-        ) {
-            return true;
-        }
-        return false;
-    }
-
-
-    /**
-     * Prints out the return value of $this->pretty_status()
-     *
-     * @param bool $show_icons
-     * @return void
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function e_pretty_status($show_icons = false)
-    {
-        echo wp_kses($this->pretty_status($show_icons), AllowedTags::getAllowedTags());
-    }
-
-
-    /**
-     * Returns a nice version of the status for displaying to customers
-     *
-     * @param bool $show_icons
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function pretty_status($show_icons = false)
-    {
-        $status = EEM_Status::instance()->localized_status(
-            [$this->status_ID() => esc_html__('unknown', 'event_espresso')],
-            false,
-            'sentence'
-        );
-        $icon   = '';
-        switch ($this->status_ID()) {
-            case RegStatus::APPROVED:
-                $icon = $show_icons
-                    ? '<span class="dashicons dashicons-star-filled ee-icon-size-16 green-text"></span>'
-                    : '';
-                break;
-            case RegStatus::PENDING_PAYMENT:
-                $icon = $show_icons
-                    ? '<span class="dashicons dashicons-star-half ee-icon-size-16 orange-text"></span>'
-                    : '';
-                break;
-            case RegStatus::AWAITING_REVIEW:
-                $icon = $show_icons
-                    ? '<span class="dashicons dashicons-marker ee-icon-size-16 orange-text"></span>'
-                    : '';
-                break;
-            case RegStatus::CANCELLED:
-                $icon = $show_icons
-                    ? '<span class="dashicons dashicons-no ee-icon-size-16 lt-grey-text"></span>'
-                    : '';
-                break;
-            case RegStatus::INCOMPLETE:
-                $icon = $show_icons
-                    ? '<span class="dashicons dashicons-no ee-icon-size-16 lt-orange-text"></span>'
-                    : '';
-                break;
-            case RegStatus::DECLINED:
-                $icon = $show_icons
-                    ? '<span class="dashicons dashicons-no ee-icon-size-16 red-text"></span>'
-                    : '';
-                break;
-            case RegStatus::WAIT_LIST:
-                $icon = $show_icons
-                    ? '<span class="dashicons dashicons-clipboard ee-icon-size-16 purple-text"></span>'
-                    : '';
-                break;
-        }
-        return $icon . $status[ $this->status_ID() ];
-    }
-
-
-    /**
-     *        get Attendee Is Going
-     */
-    public function att_is_going()
-    {
-        return $this->get('REG_att_is_going');
-    }
-
-
-    /**
-     * Gets related answers
-     *
-     * @param array $query_params @see
-     *                            https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return EE_Answer[]|EE_Base_Class[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function answers($query_params = [])
-    {
-        return $this->get_many_related('Answer', $query_params);
-    }
-
-
-    /**
-     * Gets the registration's answer value to the specified question
-     * (either the question's ID or a question object)
-     *
-     * @param EE_Question|int $question
-     * @param bool            $pretty_value
-     * @return array|string if pretty_value= true, the result will always be a string
-     * (because the answer might be an array of answer values, so passing pretty_value=true
-     * will convert it into some kind of string)
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function answer_value_to_question($question, $pretty_value = true)
-    {
-        $question_id = EEM_Question::instance()->ensure_is_ID($question);
-        return EEM_Answer::instance()->get_answer_value_to_question($this, $question_id, $pretty_value);
-    }
-
-
-    /**
-     * question_groups
-     * returns an array of EE_Question_Group objects for this registration
-     *
-     * @return EE_Question_Group[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function question_groups()
-    {
-        return EEM_Event::instance()->get_question_groups_for_event($this->event_ID(), $this);
-    }
-
-
-    /**
-     * count_question_groups
-     * returns a count of the number of EE_Question_Group objects for this registration
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function count_question_groups()
-    {
-        return EEM_Event::instance()->count_related(
-            $this->event_ID(),
-            'Question_Group',
-            [
-                [
-                    'Event_Question_Group.'
-                    . EEM_Event_Question_Group::instance()->fieldNameForContext($this->is_primary_registrant()) => true,
-                ],
-            ]
-        );
-    }
-
-
-    /**
-     * Returns the registration date in the 'standard' string format
-     * (function may be improved in the future to allow for different formats and timezones)
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function reg_date()
-    {
-        return $this->get_datetime('REG_date');
-    }
-
-
-    /**
-     * Gets the datetime-ticket for this registration (ie, it can be used to isolate
-     * the ticket this registration purchased, or the datetime they have registered
-     * to attend)
-     *
-     * @return EE_Base_Class|EE_Datetime_Ticket
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function datetime_ticket()
-    {
-        return $this->get_first_related('Datetime_Ticket');
-    }
-
-
-    /**
-     * Sets the registration's datetime_ticket.
-     *
-     * @param EE_Datetime_Ticket $datetime_ticket
-     * @return EE_Base_Class|EE_Datetime_Ticket
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_datetime_ticket($datetime_ticket)
-    {
-        return $this->_add_relation_to($datetime_ticket, 'Datetime_Ticket');
-    }
-
-
-    /**
-     * Gets deleted
-     *
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function deleted()
-    {
-        return $this->get('REG_deleted');
-    }
-
-
-    /**
-     * Sets deleted
-     *
-     * @param boolean $deleted
-     * @return void
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function set_deleted($deleted)
-    {
-        if ($deleted) {
-            $this->delete();
-        } else {
-            $this->restore();
-        }
-    }
-
-
-    /**
-     * Get the status object of this object
-     *
-     * @return EE_Base_Class|EE_Status
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function status_obj()
-    {
-        return $this->get_first_related('Status');
-    }
-
-
-    /**
-     * Returns the number of times this registration has checked into any of the datetimes it's available for
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function count_checkins()
-    {
-        return $this->get_model()->count_related($this, 'Checkin');
-    }
-
-
-    /**
-     * Returns the number of current Check-ins this registration is checked into for any of the datetimes the
-     * registration is for.  Note, this is ONLY checked in (does not include checked out)
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function count_checkins_not_checkedout()
-    {
-        return $this->get_model()->count_related($this, 'Checkin', [['CHK_in' => 1]]);
-    }
-
-
-    /**
-     * The purpose of this method is simply to check whether this registration can check in to the given datetime.
-     *
-     * @param int | EE_Datetime $DTT_OR_ID      The datetime the registration is being checked against
-     * @param bool              $check_approved This is used to indicate whether the caller wants can_checkin to also
-     *                                          consider registration status as well as datetime access.
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function can_checkin($DTT_OR_ID, $check_approved = true)
-    {
-        $DTT_ID = EEM_Datetime::instance()->ensure_is_ID($DTT_OR_ID);
-        // first check registration status
-        if (! $DTT_ID || ($check_approved && ! $this->is_approved())) {
-            return false;
-        }
-        // is there a datetime ticket that matches this dtt_ID?
-        if (
-            ! (EEM_Datetime_Ticket::instance()->exists(
-                [
-                    [
-                        'TKT_ID' => $this->get('TKT_ID'),
-                        'DTT_ID' => $DTT_ID,
-                    ],
-                ]
-            ))
-        ) {
-            return false;
-        }
-
-        // final check is against TKT_uses
-        return $this->verify_can_checkin_against_TKT_uses($DTT_ID);
-    }
-
-
-    /**
-     * This method verifies whether the user can check in for the given datetime considering the max uses value set on
-     * the ticket. To do this,  a query is done to get the count of the datetime records already checked into.  If the
-     * datetime given does not have a check-in record and checking in for that datetime will exceed the allowed uses,
-     * then return false.  Otherwise return true.
-     *
-     * @param int | EE_Datetime $DTT_OR_ID The datetime the registration is being checked against
-     * @return bool true means can check in.  false means cannot check in.
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function verify_can_checkin_against_TKT_uses($DTT_OR_ID)
-    {
-        $DTT_ID = EEM_Datetime::instance()->ensure_is_ID($DTT_OR_ID);
-
-        if (! $DTT_ID) {
-            return false;
-        }
-
-        $max_uses = $this->ticket() instanceof EE_Ticket
-            ? $this->ticket()->uses()
-            : EE_INF;
-
-        // if max uses is not set or equals infinity then return true
-        // because it's not a factor for whether user can check in or not.
-        if (! $max_uses || $max_uses === EE_INF) {
-            return true;
-        }
-
-        // does this datetime have a check-in record?  If so, then the dtt count has already been verified so we can just
-        // go ahead and toggle.
-        if (EEM_Checkin::instance()->exists([['REG_ID' => $this->ID(), 'DTT_ID' => $DTT_ID]])) {
-            return true;
-        }
-
-        // made it here so the last check is whether the number of check-ins per unique datetime on this registration
-        // disallows further check-ins.
-        $count_unique_dtt_checkins = EEM_Checkin::instance()->count(
-            [
-                [
-                    'REG_ID' => $this->ID(),
-                    'CHK_in' => true,
-                ],
-            ],
-            'DTT_ID',
-            true
-        );
-        // check-ins have already reached their max number of uses
-        // so registrant can NOT check in
-        if ($count_unique_dtt_checkins >= $max_uses) {
-            EE_Error::add_error(
-                esc_html__(
-                    'Check-in denied because number of datetime uses for the ticket has been reached or exceeded.',
-                    'event_espresso'
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-            return false;
-        }
-        return true;
-    }
-
-
-    /**
-     * toggle Check-in status for this registration
-     * Check-ins are toggled in the following order:
-     * never checked in -> checked in
-     * checked in -> checked out
-     * checked out -> checked in
-     *
-     * @param int  $DTT_ID  include specific datetime to toggle Check-in for.
-     *                      If not included or null, then it is assumed latest datetime is being toggled.
-     * @param bool $verify  If true then can_checkin() is used to verify whether the person
-     *                      can be checked in or not.  Otherwise this forces change in check-in status.
-     * @return bool|int     the chk_in status toggled to OR false if nothing got changed.
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function toggle_checkin_status($DTT_ID = null, $verify = false)
-    {
-        if (empty($DTT_ID)) {
-            $datetime = $this->get_latest_related_datetime();
-            $DTT_ID   = $datetime instanceof EE_Datetime ? $datetime->ID() : 0;
-            // verify the registration can check in for the given DTT_ID
-        } elseif (! $this->can_checkin($DTT_ID, $verify)) {
-            EE_Error::add_error(
-                sprintf(
-                    esc_html__(
-                        'The given registration (ID:%1$d) can not be checked in to the given DTT_ID (%2$d), because the registration does not have access',
-                        'event_espresso'
-                    ),
-                    $this->ID(),
-                    $DTT_ID
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-            return false;
-        }
-        $status_paths = [
-            EE_Checkin::status_checked_never => EE_Checkin::status_checked_in,
-            EE_Checkin::status_checked_in    => EE_Checkin::status_checked_out,
-            EE_Checkin::status_checked_out   => EE_Checkin::status_checked_in,
-        ];
-        // start by getting the current status so we know what status we'll be changing to.
-        $cur_status = $this->check_in_status_for_datetime($DTT_ID);
-        $status_to  = $status_paths[ $cur_status ];
-        // database only records true for checked IN or false for checked OUT
-        // no record ( null ) means checked in NEVER, but we obviously don't save that
-        $new_status = $status_to === EE_Checkin::status_checked_in;
-        // add relation - note Check-ins are always creating new rows
-        // because we are keeping track of Check-ins over time.
-        // Eventually we'll probably want to show a list table
-        // for the individual Check-ins so that they can be managed.
-        $checkin = EE_Checkin::new_instance(
-            [
-                'REG_ID' => $this->ID(),
-                'DTT_ID' => $DTT_ID,
-                'CHK_in' => $new_status,
-            ]
-        );
-        // if the record could not be saved then return false
-        if ($checkin->save() === 0) {
-            if (WP_DEBUG) {
-                global $wpdb;
-                $error = sprintf(
-                    esc_html__(
-                        'Registration check in update failed because of the following database error: %1$s%2$s',
-                        'event_espresso'
-                    ),
-                    '<br />',
-                    $wpdb->last_error
-                );
-            } else {
-                $error = esc_html__(
-                    'Registration check in update failed because of an unknown database error',
-                    'event_espresso'
-                );
-            }
-            EE_Error::add_error($error, __FILE__, __FUNCTION__, __LINE__);
-            return false;
-        }
-        // Fire a checked_in and checkout_out action.
-        $checked_status = $status_to === EE_Checkin::status_checked_in
-            ? 'checked_in'
-            : 'checked_out';
-        do_action("AHEE__EE_Registration__toggle_checkin_status__{$checked_status}", $this, $DTT_ID);
-        return $status_to;
-    }
-
-
-    /**
-     * Returns the latest datetime related to this registration (via the ticket attached to the registration).
-     * "Latest" is defined by the `DTT_EVT_start` column.
-     *
-     * @return EE_Datetime|null
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_latest_related_datetime(): ?EE_Datetime
-    {
-        return EEM_Datetime::instance()->get_one(
-            [
-                [
-                    'Ticket.Registration.REG_ID' => $this->ID(),
-                ],
-                'order_by' => ['DTT_EVT_start' => 'DESC'],
-            ]
-        );
-    }
-
-
-    /**
-     * Returns the earliest datetime related to this registration (via the ticket attached to the registration).
-     * "Earliest" is defined by the `DTT_EVT_start` column.
-     *
-     * @return EE_Base_Class|EE_Soft_Delete_Base_Class|NULL
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_earliest_related_datetime()
-    {
-        return EEM_Datetime::instance()->get_one(
-            [
-                [
-                    'Ticket.Registration.REG_ID' => $this->ID(),
-                ],
-                'order_by' => ['DTT_EVT_start' => 'ASC'],
-            ]
-        );
-    }
-
-
-    /**
-     * This method simply returns the check-in status for this registration and the given datetime.
-     * If neither the datetime nor the check-in values are provided as arguments,
-     * then this will return the LATEST check-in status for the registration across all datetimes it belongs to.
-     *
-     * @param int|null        $DTT_ID  The ID of the datetime we're checking against
-     *                                 (if empty we'll get the primary datetime for
-     *                                 this registration (via event) and use its ID);
-     * @param EE_Checkin|null $checkin If present, we use the given check-in object rather than the dtt_id.
-     * @return int                     Integer representing Check-in status.
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function check_in_status_for_datetime(?int $DTT_ID = 0, ?EE_Checkin $checkin = null): int
-    {
-        if ($checkin instanceof EE_Checkin) {
-            return $checkin->status();
-        }
-
-        if (! $DTT_ID) {
-            return EE_Checkin::status_invalid;
-        }
-
-        $checkin_query_params = [
-            0          => ['DTT_ID' => $DTT_ID],
-            'order_by' => ['CHK_timestamp' => 'DESC'],
-        ];
-
-        $checkin = $this->get_first_related(
-            'Checkin',
-            $checkin_query_params
-        );
-        return $checkin instanceof EE_Checkin ? $checkin->status() : EE_Checkin::status_checked_never;
-    }
-
-
-    /**
-     * This method returns a localized message for the toggled Check-in message.
-     *
-     * @param int|null $DTT_ID include specific datetime to get the correct Check-in message.  If not included or null,
-     *                         then it is assumed Check-in for primary datetime was toggled.
-     * @param bool     $error  This just flags that you want an error message returned. This is put in so that the error
-     *                         message can be customized with the attendee name.
-     * @return string internationalized message
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_checkin_msg(?int $DTT_ID, bool $error = false): string
-    {
-        // let's get the attendee first so we can include the name of the attendee
-        $attendee = $this->attendee();
-        if ($attendee instanceof EE_Attendee) {
-            if ($error) {
-                return sprintf(
-                    esc_html__("%s's check-in status was not changed.", "event_espresso"),
-                    $attendee->full_name()
-                );
-            }
-            $cur_status = $this->check_in_status_for_datetime($DTT_ID);
-            // what is the status message going to be?
-            switch ($cur_status) {
-                case EE_Checkin::status_checked_never:
-                    return sprintf(
-                        esc_html__('%s has been removed from Check-in records', 'event_espresso'),
-                        $attendee->full_name()
-                    );
-                case EE_Checkin::status_checked_in:
-                    return sprintf(esc_html__('%s has been checked in', 'event_espresso'), $attendee->full_name());
-                case EE_Checkin::status_checked_out:
-                    return sprintf(esc_html__('%s has been checked out', 'event_espresso'), $attendee->full_name());
-            }
-        }
-        return esc_html__('The check-in status could not be determined.', 'event_espresso');
-    }
-
-
-    /**
-     * Returns the related EE_Transaction to this registration
-     *
-     * @return EE_Transaction
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws ReflectionException
-     */
-    public function transaction(): EE_Transaction
-    {
-        $TXN_ID = $this->transaction_ID();
-        $transaction = $TXN_ID
-            ? EEM_Transaction::instance()->get_one_by_ID($TXN_ID)
-            : $this->get_one_from_cache('Transaction');
-        if (! $transaction instanceof \EE_Transaction) {
-            throw new EntityNotFoundException('Transaction ID', $this->transaction_ID());
-        }
-        return $transaction;
-    }
-
-
-    /**
-     * get Registration Code
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function reg_code(): string
-    {
-        return $this->get('REG_code')
-            ?: '';
-    }
-
-
-    /**
-     * @return mixed
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function transaction_ID()
-    {
-        return $this->get('TXN_ID');
-    }
-
-
-    /**
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function ticket_ID()
-    {
-        return $this->get('TKT_ID');
-    }
-
-
-    /**
-     * Set Registration Code
-     *
-     * @param RegCode|string $REG_code Registration Code
-     * @param boolean        $use_default
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_reg_code($REG_code, bool $use_default = false)
-    {
-        if (! $this->reg_code()) {
-            parent::set('REG_code', $REG_code, $use_default);
-        } elseif (empty($REG_code)) {
-            EE_Error::add_error(
-                esc_html__('REG_code can not be empty.', 'event_espresso'),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-        } else {
-            EE_Error::doing_it_wrong(
-                __CLASS__ . '::' . __FUNCTION__,
-                esc_html__('Can not change a registration REG_code once it has been set.', 'event_espresso'),
-                '4.6.0'
-            );
-        }
-    }
-
-
-    /**
-     * Returns all other registrations in the same group as this registrant who have the same ticket option.
-     * Note, if you want to just get all registrations in the same transaction (group), use:
-     *    $registration->transaction()->registrations();
-     *
-     * @return EE_Registration[] or empty array if this isn't a group registration.
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @since 4.5.0
-     */
-    public function get_all_other_registrations_in_group()
-    {
-        if ($this->group_size() < 2) {
-            return [];
-        }
-
-        $query[0] = [
-            'TXN_ID' => $this->transaction_ID(),
-            'REG_ID' => ['!=', $this->ID()],
-            'TKT_ID' => $this->ticket_ID(),
-        ];
-        /** @var EE_Registration[] $registrations */
-        $registrations = $this->get_model()->get_all($query);
-        return $registrations;
-    }
-
-
-    /**
-     * Return the link to the admin details for the object.
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_admin_details_link()
-    {
-        EE_Registry::instance()->load_helper('URL');
-        return EEH_URL::add_query_args_and_nonce(
-            [
-                'page'    => 'espresso_registrations',
-                'action'  => 'view_registration',
-                '_REG_ID' => $this->ID(),
-            ],
-            admin_url('admin.php')
-        );
-    }
-
-
-    /**
-     * Returns the link to the editor for the object.  Sometimes this is the same as the details.
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_admin_edit_link()
-    {
-        return $this->get_admin_details_link();
-    }
-
-
-    /**
-     * Returns the link to a settings page for the object.
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_admin_settings_link()
-    {
-        return $this->get_admin_details_link();
-    }
-
-
-    /**
-     * Returns the link to the "overview" for the object (typically the "list table" view).
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_admin_overview_link()
-    {
-        EE_Registry::instance()->load_helper('URL');
-        return EEH_URL::add_query_args_and_nonce(
-            [
-                'page' => 'espresso_registrations',
-            ],
-            admin_url('admin.php')
-        );
-    }
-
-
-    /**
-     * @param array $query_params
-     * @return EE_Base_Class[]|EE_Registration[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function payments($query_params = [])
-    {
-        return $this->get_many_related('Payment', $query_params);
-    }
-
-
-    /**
-     * @param array $query_params
-     * @return EE_Base_Class[]|EE_Registration_Payment[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function registration_payments($query_params = [])
-    {
-        return $this->get_many_related('Registration_Payment', $query_params);
-    }
-
-
-    /**
-     * This grabs the payment method corresponding to the last payment made for the amount owing on the registration.
-     * Note: if there are no payments on the registration there will be no payment method returned.
-     *
-     * @return EE_Payment|EE_Payment_Method|null
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     */
-    public function payment_method()
-    {
-        return EEM_Payment_Method::instance()->get_last_used_for_registration($this);
-    }
-
-
-    /**
-     * @return \EE_Line_Item
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function ticket_line_item()
-    {
-        $ticket            = $this->ticket();
-        $transaction       = $this->transaction();
-        $line_item         = null;
-        $ticket_line_items = \EEH_Line_Item::get_line_items_by_object_type_and_IDs(
-            $transaction->total_line_item(),
-            'Ticket',
-            [$ticket->ID()]
-        );
-        foreach ($ticket_line_items as $ticket_line_item) {
-            if (
-                $ticket_line_item instanceof \EE_Line_Item
-                && $ticket_line_item->OBJ_type() === 'Ticket'
-                && $ticket_line_item->OBJ_ID() === $ticket->ID()
-            ) {
-                $line_item = $ticket_line_item;
-                break;
-            }
-        }
-        if (! ($line_item instanceof \EE_Line_Item && $line_item->OBJ_type() === 'Ticket')) {
-            throw new EntityNotFoundException('Line Item Ticket ID', $ticket->ID());
-        }
-        return $line_item;
-    }
-
-
-    /**
-     * Soft Deletes this model object.
-     *
-     * @param string $source function name that called this method
-     * @return boolean | int
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function delete()
-    {
-        if ($this->update_extra_meta(EE_Registration::PRE_TRASH_REG_STATUS_KEY, $this->status_ID()) === true) {
-            $this->set_status(
-                RegStatus::CANCELLED,
-                false,
-                new Context(
-                    __METHOD__,
-                    esc_html__('Executed when a registration is trashed.', 'event_espresso')
-                )
-            );
-        }
-        return parent::delete();
-    }
-
-
-    /**
-     * Restores whatever the previous status was on a registration before it was trashed (if possible)
-     *
-     * @param string $source function name that called this method
-     * @return bool|int
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function restore()
-    {
-        $previous_status = $this->get_extra_meta(
-            EE_Registration::PRE_TRASH_REG_STATUS_KEY,
-            true,
-            RegStatus::CANCELLED
-        );
-        if ($previous_status) {
-            $this->delete_extra_meta(EE_Registration::PRE_TRASH_REG_STATUS_KEY);
-            $this->set_status(
-                $previous_status,
-                false,
-                new Context(
-                    __METHOD__,
-                    esc_html__('Executed when a trashed registration is restored.', 'event_espresso')
-                )
-            );
-        }
-        return parent::restore();
-    }
-
-
-    /**
-     * possibly toggle Registration status based on comparison of REG_paid vs REG_final_price
-     *
-     * @param boolean $trigger_set_status_logic  EE_Registration::set_status() can trigger additional logic
-     *                                           depending on whether the reg status changes to or from "Approved"
-     * @return boolean whether the Registration status was updated
-     * @throws DomainException
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws UnexpectedEntityException
-     */
-    public function updateStatusBasedOnTotalPaid($trigger_set_status_logic = true)
-    {
-        $paid  = $this->paid();
-        $price = $this->final_price();
-        switch (true) {
-            // overpaid or paid
-            case EEH_Money::compare_floats($paid, $price, '>'):
-            case EEH_Money::compare_floats($paid, $price):
-                $new_status = RegStatus::APPROVED;
-                break;
-            //  underpaid
-            case EEH_Money::compare_floats($paid, $price, '<'):
-                $new_status = RegStatus::PENDING_PAYMENT;
-                break;
-            // uhhh Houston...
-            default:
-                throw new RuntimeException(
-                    esc_html__('The total paid calculation for this registration is inaccurate.', 'event_espresso')
-                );
-        }
-        if ($new_status !== $this->status_ID()) {
-            if ($trigger_set_status_logic) {
-                return $this->set_status(
-                    $new_status,
-                    false,
-                    new Context(
-                        __METHOD__,
-                        esc_html__(
-                            'Executed when the registration status is updated based on total paid.',
-                            'event_espresso'
-                        )
-                    )
-                );
-            }
-            parent::set('STS_ID', $new_status);
-            return true;
-        }
-        return false;
-    }
-
-
-    /*************************** DEPRECATED ***************************/
-
-
-    /**
-     * @deprecated
-     * @since     4.7.0
-     */
-    public function price_paid()
-    {
-        EE_Error::doing_it_wrong(
-            'EE_Registration::price_paid()',
-            esc_html__(
-                'This method is deprecated, please use EE_Registration::final_price() instead.',
-                'event_espresso'
-            ),
-            '4.7.0'
-        );
-        return $this->final_price();
-    }
-
-
-    /**
-     * @param float $REG_final_price
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     * @throws DomainException
-     * @deprecated
-     * @since     4.7.0
-     */
-    public function set_price_paid($REG_final_price = 0.00)
-    {
-        EE_Error::doing_it_wrong(
-            'EE_Registration::set_price_paid()',
-            esc_html__(
-                'This method is deprecated, please use EE_Registration::set_final_price() instead.',
-                'event_espresso'
-            ),
-            '4.7.0'
-        );
-        $this->set_final_price($REG_final_price);
-    }
-
-
-    /**
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @deprecated
-     * @since 4.7.0
-     */
-    public function pretty_price_paid()
-    {
-        EE_Error::doing_it_wrong(
-            'EE_Registration::pretty_price_paid()',
-            esc_html__(
-                'This method is deprecated, please use EE_Registration::pretty_final_price() instead.',
-                'event_espresso'
-            ),
-            '4.7.0'
-        );
-        return $this->pretty_final_price();
-    }
-
-
-    /**
-     * Gets the primary datetime related to this registration via the related Event to this registration
-     *
-     * @return EE_Datetime
-     * @throws EE_Error
-     * @throws EntityNotFoundException
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @deprecated 4.9.17
-     */
-    public function get_related_primary_datetime()
-    {
-        EE_Error::doing_it_wrong(
-            __METHOD__,
-            esc_html__(
-                'Use EE_Registration::get_latest_related_datetime() or EE_Registration::get_earliest_related_datetime()',
-                'event_espresso'
-            ),
-            '4.9.17',
-            '5.0.0'
-        );
-        return $this->event()->primary_datetime();
-    }
-
-
-    /**
-     * Returns the contact's name (or "Unknown" if there is no contact.)
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @since 4.10.12.p
-     */
-    public function name()
-    {
-        return $this->attendeeName();
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function wasMoved(): bool
-    {
-        // only need to check 'registration-moved-to' because
-        // the existence of a new REG ID means the registration was moved
-        $reg_moved = $this->get_extra_meta('registration-moved-to', true, []);
-        return isset($reg_moved['NEW_REG_ID']) && $reg_moved['NEW_REG_ID'];
-    }
-
-
-    /**
-     * @param EE_Payment $payment
-     * @param float|null $amount
-     * @return float
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since 5.0.8.p
-     */
-    public function applyPayment(EE_Payment $payment, ?float $amount = null): float
-    {
-        $payment_amount = $amount ?? $payment->amount();
-        // ensure $payment_amount is NOT negative
-        $payment_amount = (float) abs($payment_amount);
-        $payment_amount = $payment->is_a_refund()
-            ? $this->processRefund($payment_amount)
-            : $this->processPayment($payment_amount);
-        if ($payment_amount) {
-            $reg_payment = EEM_Registration_Payment::instance()->get_one(
-                [['REG_ID' => $this->ID(), 'PAY_ID' => $payment->ID()]]
-            );
-            // if existing registration payment exists
-            if ($reg_payment instanceof EE_Registration_Payment) {
-                // then update that record
-                $reg_payment->set_amount($payment_amount);
-            } else {
-                // or add new relation between registration and payment and set amount
-                $reg_payment = EE_Registration_Payment::new_instance(
-                    [
-                        'REG_ID'     => $this->ID(),
-                        'PAY_ID'     => $payment->ID(),
-                        'RPY_amount' => $payment_amount,
-                    ]
-                );
-            }
-            $reg_payment->save();
-        }
-        return $payment_amount;
-    }
-
-
-    /**
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    private function processPayment(float $payment_amount): float
-    {
-        $paid  = $this->paid();
-        $owing = $this->final_price() - $paid;
-        if ($owing <= 0) {
-            return 0.0;
-        }
-        // don't allow payment amount to exceed the incoming amount, OR the amount owing
-        $payment_amount = min($payment_amount, $owing);
-        $paid           = $paid + $payment_amount;
-        // calculate and set new REG_paid
-        $this->set_paid($paid);
-        // make it stick
-        $this->save();
-        return (float) $payment_amount;
-    }
-
-
-    /**
-     * @throws ReflectionException
-     * @throws EE_Error
-     */
-    private function processRefund(float $payment_amount): float
-    {
-        $paid = $this->paid();
-        if ($paid <= 0) {
-            return 0.0;
-        }
-        // don't allow refund amount to exceed the incoming amount, OR the amount paid
-        $payment_amount = min($payment_amount, $paid);
-        // calculate and set new REG_paid
-        $paid = $paid - $payment_amount;
-        $this->set_paid($paid);
-        // make it stick
-        $this->save();
-        // convert payment amount back to a negative value for storage in the db
-        return (float) $payment_amount;
-    }
-
-
-    /**
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since 5.0.20.p
-     */
-    public function defaultRegistrationStatus(): string
-    {
-        $default_event_reg_status = $this->event()->default_registration_status();
-        $default_reg_status = (string) apply_filters(
-            'AFEE__EE_Registration__defaultRegistrationStatus__default_reg_status',
-            $default_event_reg_status,
-            $this
-        );
-        return RegStatus::isValidStatus($default_reg_status, false)
-            ? $default_reg_status
-            : $default_event_reg_status;
-    }
+	/**
+	 * Used to reference when a registration has never been checked in.
+	 *
+	 * @deprecated use \EE_Checkin::status_checked_never instead
+	 * @type int
+	 */
+	const checkin_status_never = 2;
+
+	/**
+	 * Used to reference when a registration has been checked in.
+	 *
+	 * @deprecated use \EE_Checkin::status_checked_in instead
+	 * @type int
+	 */
+	const checkin_status_in = 1;
+
+	/**
+	 * Used to reference when a registration has been checked out.
+	 *
+	 * @deprecated use \EE_Checkin::status_checked_out instead
+	 * @type int
+	 */
+	const checkin_status_out = 0;
+
+	/**
+	 * extra meta key for tracking reg status os trashed registrations
+	 *
+	 * @type string
+	 */
+	const PRE_TRASH_REG_STATUS_KEY = 'pre_trash_registration_status';
+
+	/**
+	 * extra meta key for tracking if registration has reserved ticket
+	 *
+	 * @type string
+	 */
+	const HAS_RESERVED_TICKET_KEY = 'has_reserved_ticket';
+
+
+	/**
+	 * @param array  $props_n_values          incoming values
+	 * @param string $timezone                incoming timezone (if not set the timezone set for the website will be
+	 *                                        used.)
+	 * @param array  $date_formats            incoming date_formats in an array where the first value is the
+	 *                                        date_format and the second value is the time format
+	 * @return EE_Registration
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function new_instance($props_n_values = [], $timezone = '', $date_formats = [])
+	{
+		$has_object = parent::_check_for_object($props_n_values, __CLASS__, $timezone, $date_formats);
+		return $has_object
+			?: new self($props_n_values, false, $timezone, $date_formats);
+	}
+
+
+	/**
+	 * @param array  $props_n_values  incoming values from the database
+	 * @param string $timezone        incoming timezone as set by the model.  If not set the timezone for
+	 *                                the website will be used.
+	 * @return EE_Registration
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function new_instance_from_db($props_n_values = [], $timezone = '')
+	{
+		return new self($props_n_values, true, $timezone);
+	}
+
+
+	/**
+	 *        Set Event ID
+	 *
+	 * @param int $EVT_ID Event ID
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function set_event($EVT_ID = 0)
+	{
+		$this->set('EVT_ID', $EVT_ID);
+	}
+
+
+	/**
+	 * Overrides parent set() method so that all calls to set( 'REG_code', $REG_code ) OR set( 'STS_ID', $STS_ID ) can
+	 * be routed to internal methods
+	 *
+	 * @param string $field_name
+	 * @param mixed  $field_value
+	 * @param bool   $use_default
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function set($field_name, $field_value, $use_default = false)
+	{
+		switch ($field_name) {
+			case 'REG_code':
+				if (! empty($field_value) && ! $this->reg_code()) {
+					$this->set_reg_code($field_value, $use_default);
+				}
+				break;
+			case 'STS_ID':
+				$this->set_status((string) $field_value, $use_default);
+				break;
+			default:
+				parent::set($field_name, $field_value, $use_default);
+		}
+	}
+
+
+	/**
+	 * Set Status ID
+	 * updates the registration status and ALSO...
+	 * calls reserve_registration_space() if the reg status changes TO approved from any other reg status
+	 * calls release_registration_space() if the reg status changes FROM approved to any other reg status
+	 *
+	 * @param string                $new_STS_ID
+	 * @param boolean               $use_default
+	 * @param ContextInterface|null $context
+	 * @return bool
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function set_status(
+		string $new_STS_ID = '',
+		bool $use_default = false,
+		?ContextInterface $context = null
+	): bool {
+		// get current REG_Status
+		$old_STS_ID = $this->status_ID();
+		$new_STS_ID = (string) apply_filters(
+			'AFEE__EE_Registration__set_status__new_STS_ID',
+			$new_STS_ID,
+			$context,
+			$this
+		);
+		// it's still good to allow the parent set method to have a say
+		parent::set('STS_ID', (! empty($new_STS_ID) ? $new_STS_ID : null), $use_default);
+		// if status has changed
+		if (
+			$old_STS_ID !== $new_STS_ID // and that status has actually changed
+			&& ! empty($old_STS_ID) // and that old status is actually set
+			&& ! empty($new_STS_ID) // as well as the new status
+			&& $this->ID() // ensure registration is in the db
+		) {
+			// THEN handle other changes that occur when reg status changes
+			// TO approved
+			if ($new_STS_ID === RegStatus::APPROVED) {
+				// reserve a space by incrementing ticket and datetime sold values
+				$this->reserveRegistrationSpace();
+				do_action('AHEE__EE_Registration__set_status__to_approved', $this, $old_STS_ID, $new_STS_ID, $context);
+				// OR FROM  approved
+			} elseif ($old_STS_ID === RegStatus::APPROVED) {
+				// release a space by decrementing ticket and datetime sold values
+				$this->releaseRegistrationSpace();
+				do_action(
+					'AHEE__EE_Registration__set_status__from_approved',
+					$this,
+					$old_STS_ID,
+					$new_STS_ID,
+					$context
+				);
+			}
+			$this->updateIfCanceledOrReinstated($new_STS_ID, $old_STS_ID, $context);
+			if ($this->statusChangeUpdatesTransaction($context)) {
+				$this->updateTransactionAfterStatusChange();
+			}
+			do_action('AHEE__EE_Registration__set_status__after_update', $this, $old_STS_ID, $new_STS_ID, $context);
+		}
+		return ! empty($new_STS_ID);
+	}
+
+
+	/**
+	 * update REGs and TXN when cancelled or declined registrations involved
+	 *
+	 * @param string                $new_STS_ID
+	 * @param string                $old_STS_ID
+	 * @param ContextInterface|null $context
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 */
+	private function updateIfCanceledOrReinstated($new_STS_ID, $old_STS_ID, ?ContextInterface $context = null)
+	{
+		// these reg statuses should not be considered in any calculations involving monies owing
+		$closed_reg_statuses = EEM_Registration::closed_reg_statuses();
+		// true if registration has been cancelled or declined
+		$this->updateIfCanceled(
+			$closed_reg_statuses,
+			$new_STS_ID,
+			$old_STS_ID,
+			$context
+		);
+		$this->updateIfReinstated(
+			$closed_reg_statuses,
+			$new_STS_ID,
+			$old_STS_ID,
+			$context
+		);
+	}
+
+
+	/**
+	 * update REGs and TXN when cancelled or declined registrations involved
+	 *
+	 * @param array                 $closed_reg_statuses
+	 * @param string                $new_STS_ID
+	 * @param string                $old_STS_ID
+	 * @param ContextInterface|null $context
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 */
+	private function updateIfCanceled(
+		array $closed_reg_statuses,
+		$new_STS_ID,
+		$old_STS_ID,
+		?ContextInterface $context = null
+	) {
+		// true if registration has been cancelled or declined
+		if (
+			in_array($new_STS_ID, $closed_reg_statuses, true)
+			&& ! in_array($old_STS_ID, $closed_reg_statuses, true)
+		) {
+			/** @type EE_Registration_Processor $registration_processor */
+			$registration_processor = EE_Registry::instance()->load_class('Registration_Processor');
+			/** @type EE_Transaction_Processor $transaction_processor */
+			$transaction_processor = EE_Registry::instance()->load_class('Transaction_Processor');
+			// cancelled or declined registration
+			$registration_processor->update_registration_after_being_canceled_or_declined(
+				$this,
+				$closed_reg_statuses
+			);
+			$transaction_processor->update_transaction_after_canceled_or_declined_registration(
+				$this,
+				$closed_reg_statuses,
+				false
+			);
+			do_action(
+				'AHEE__EE_Registration__set_status__canceled_or_declined',
+				$this,
+				$old_STS_ID,
+				$new_STS_ID,
+				$context
+			);
+		}
+	}
+
+
+	/**
+	 * update REGs and TXN when cancelled or declined registrations involved
+	 *
+	 * @param array                 $closed_reg_statuses
+	 * @param string                $new_STS_ID
+	 * @param string                $old_STS_ID
+	 * @param ContextInterface|null $context
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 */
+	private function updateIfReinstated(
+		array $closed_reg_statuses,
+		$new_STS_ID,
+		$old_STS_ID,
+		?ContextInterface $context = null
+	) {
+		// true if reinstating cancelled or declined registration
+		if (
+			in_array($old_STS_ID, $closed_reg_statuses, true)
+			&& ! in_array($new_STS_ID, $closed_reg_statuses, true)
+		) {
+			/** @type EE_Registration_Processor $registration_processor */
+			$registration_processor = EE_Registry::instance()->load_class('Registration_Processor');
+			/** @type EE_Transaction_Processor $transaction_processor */
+			$transaction_processor = EE_Registry::instance()->load_class('Transaction_Processor');
+			// reinstating cancelled or declined registration
+			$registration_processor->update_canceled_or_declined_registration_after_being_reinstated(
+				$this,
+				$closed_reg_statuses
+			);
+			$transaction_processor->update_transaction_after_reinstating_canceled_registration(
+				$this,
+				$closed_reg_statuses,
+				false
+			);
+			do_action(
+				'AHEE__EE_Registration__set_status__after_reinstated',
+				$this,
+				$old_STS_ID,
+				$new_STS_ID,
+				$context
+			);
+		}
+	}
+
+
+	/**
+	 * @param ContextInterface|null $context
+	 * @return bool
+	 */
+	private function statusChangeUpdatesTransaction(?ContextInterface $context = null)
+	{
+		$contexts_that_do_not_update_transaction = (array) apply_filters(
+			'AHEE__EE_Registration__statusChangeUpdatesTransaction__contexts_that_do_not_update_transaction',
+			['spco_reg_step_attendee_information_process_registrations'],
+			$context,
+			$this
+		);
+		return ! (
+			$context instanceof ContextInterface
+			&& in_array($context->slug(), $contexts_that_do_not_update_transaction, true)
+		);
+	}
+
+
+	/**
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 */
+	private function updateTransactionAfterStatusChange()
+	{
+		/** @type EE_Transaction_Payments $transaction_payments */
+		$transaction_payments = EE_Registry::instance()->load_class('Transaction_Payments');
+		$transaction_payments->recalculate_transaction_total($this->transaction(), false);
+		$this->transaction()->update_status_based_on_total_paid();
+	}
+
+
+	/**
+	 * get Status ID
+	 *
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function status_ID()
+	{
+		return $this->get('STS_ID');
+	}
+
+
+	/**
+	 * Gets the ticket this registration is for
+	 *
+	 * @param boolean $include_archived whether to include archived tickets or not.
+	 * @return EE_Ticket|EE_Base_Class
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function ticket($include_archived = true)
+	{
+		return EEM_Ticket::instance()->get_one_by_ID($this->ticket_ID());
+	}
+
+
+	/**
+	 * Gets the event this registration is for
+	 *
+	 * @return EE_Event
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function event(): EE_Event
+	{
+		$event = $this->event_obj();
+		if (! $event instanceof EE_Event) {
+			throw new EntityNotFoundException('Event ID', $this->event_ID());
+		}
+		return $event;
+	}
+
+
+	/**
+	 * Gets the "author" of the registration.  Note that for the purposes of registrations, the author will correspond
+	 * with the author of the event this registration is for.
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @since 4.5.0
+	 */
+	public function wp_user(): int
+	{
+		return $this->event()->wp_user();
+	}
+
+
+	/**
+	 * increments this registration's related ticket sold and corresponding datetime sold values
+	 *
+	 * @return void
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws UnexpectedEntityException
+	 */
+	private function reserveRegistrationSpace()
+	{
+		// reserved ticket and datetime counts will be decremented as sold counts are incremented
+		// so stop tracking that this reg has a ticket reserved
+		$this->release_reserved_ticket(false, "REG: {$this->ID()} (ln:" . __LINE__ . ')');
+		$ticket = $this->ticket();
+		$ticket->increaseSold();
+		// possibly set event status to sold out
+		$this->event()->perform_sold_out_status_check();
+	}
+
+
+	/**
+	 * decrements (subtracts) this registration's related ticket sold and corresponding datetime sold values
+	 *
+	 * @return void
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws UnexpectedEntityException
+	 */
+	private function releaseRegistrationSpace()
+	{
+		$ticket = $this->ticket();
+		$ticket->decreaseSold();
+		// possibly change event status from sold out back to previous status
+		$this->event()->perform_sold_out_status_check();
+	}
+
+
+	/**
+	 * tracks this registration's ticket reservation in extra meta
+	 * and can increment related ticket reserved and corresponding datetime reserved values
+	 *
+	 * @param bool   $update_ticket if true, will increment ticket and datetime reserved count
+	 * @param string $source
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function reserve_ticket($update_ticket = false, $source = 'unknown')
+	{
+		// only reserve ticket if space is not currently reserved
+		if ((bool) $this->get_extra_meta(EE_Registration::HAS_RESERVED_TICKET_KEY, true) !== true) {
+			$reserved = $this->update_extra_meta(EE_Registration::HAS_RESERVED_TICKET_KEY, true);
+			if ($reserved && $update_ticket) {
+				$ticket = $this->ticket();
+				$ticket->increaseReserved(1, "REG: {$this->ID()} (ln:" . __LINE__ . ')');
+				$this->update_extra_meta('reserve_ticket', "{$this->ticket_ID()} from {$source}");
+				$ticket->save();
+			}
+		}
+	}
+
+
+	/**
+	 * stops tracking this registration's ticket reservation in extra meta
+	 * decrements (subtracts) related ticket reserved and corresponding datetime reserved values
+	 *
+	 * @param bool   $update_ticket if true, will decrement ticket and datetime reserved count
+	 * @param string $source
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function release_reserved_ticket($update_ticket = false, $source = 'unknown')
+	{
+		// only release ticket if space is currently reserved
+		if ((bool) $this->get_extra_meta(EE_Registration::HAS_RESERVED_TICKET_KEY, true) === true) {
+			$reserved = $this->update_extra_meta(EE_Registration::HAS_RESERVED_TICKET_KEY, false);
+			if ($reserved && $update_ticket) {
+				$ticket = $this->ticket();
+				$ticket->decreaseReserved(1, true, "REG: {$this->ID()} (ln:" . __LINE__ . ')');
+				$this->update_extra_meta('release_reserved_ticket', "{$this->ticket_ID()} from {$source}");
+			}
+		}
+	}
+
+
+	/**
+	 * Set Attendee ID
+	 *
+	 * @param int $ATT_ID Attendee ID
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function set_attendee_id($ATT_ID = 0)
+	{
+		$this->set('ATT_ID', $ATT_ID);
+	}
+
+
+	/**
+	 *        Set Transaction ID
+	 *
+	 * @param int $TXN_ID Transaction ID
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function set_transaction_id($TXN_ID = 0)
+	{
+		$this->set('TXN_ID', $TXN_ID);
+	}
+
+
+	/**
+	 *        Set Session
+	 *
+	 * @param string $REG_session PHP Session ID
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function set_session($REG_session = '')
+	{
+		$this->set('REG_session', $REG_session);
+	}
+
+
+	/**
+	 *        Set Registration URL Link
+	 *
+	 * @param string $REG_url_link Registration URL Link
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function set_reg_url_link($REG_url_link = '')
+	{
+		$this->set('REG_url_link', $REG_url_link);
+	}
+
+
+	/**
+	 *        Set Attendee Counter
+	 *
+	 * @param int $REG_count Primary Attendee
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function set_count($REG_count = 1)
+	{
+		$this->set('REG_count', $REG_count);
+	}
+
+
+	/**
+	 *        Set Group Size
+	 *
+	 * @param boolean $REG_group_size Group Registration
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function set_group_size($REG_group_size = false)
+	{
+		$this->set('REG_group_size', $REG_group_size);
+	}
+
+
+	/**
+	 *    is_not_approved -  convenience method that returns TRUE if REG status ID ==
+	 *    RegStatus::AWAITING_REVIEW
+	 *
+	 * @return        boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_not_approved()
+	{
+		return $this->status_ID() === RegStatus::AWAITING_REVIEW;
+	}
+
+
+	/**
+	 *    is_pending_payment -  convenience method that returns TRUE if REG status ID ==
+	 *    RegStatus::PENDING_PAYMENT
+	 *
+	 * @return        boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_pending_payment()
+	{
+		return $this->status_ID() === RegStatus::PENDING_PAYMENT;
+	}
+
+
+	/**
+	 *    is_approved -  convenience method that returns TRUE if REG status ID == RegStatus::APPROVED
+	 *
+	 * @return        boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_approved()
+	{
+		return $this->status_ID() === RegStatus::APPROVED;
+	}
+
+
+	/**
+	 *    is_cancelled -  convenience method that returns TRUE if REG status ID == RegStatus::CANCELLED
+	 *
+	 * @return        boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_cancelled()
+	{
+		return $this->status_ID() === RegStatus::CANCELLED;
+	}
+
+
+	/**
+	 *    is_declined -  convenience method that returns TRUE if REG status ID == RegStatus::DECLINED
+	 *
+	 * @return        boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_declined()
+	{
+		return $this->status_ID() === RegStatus::DECLINED;
+	}
+
+
+	/**
+	 *    is_incomplete -  convenience method that returns TRUE if REG status ID ==
+	 *    RegStatus::INCOMPLETE
+	 *
+	 * @return        boolean
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_incomplete()
+	{
+		return $this->status_ID() === RegStatus::INCOMPLETE;
+	}
+
+
+	/**
+	 *        Set Registration Date
+	 *
+	 * @param mixed ( int or string ) $REG_date Registration Date - Unix timestamp or string representation of
+	 *                                                 Date
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function set_reg_date($REG_date = false)
+	{
+		$this->set('REG_date', $REG_date);
+	}
+
+
+	/**
+	 *    Set final price owing for this registration after all ticket/price modifications
+	 *
+	 * @param float $REG_final_price
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function set_final_price($REG_final_price = 0.00)
+	{
+		$this->set('REG_final_price', $REG_final_price);
+	}
+
+
+	/**
+	 *    Set amount paid towards this registration's final price
+	 *
+	 * @param float|int|string $REG_paid
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function set_paid($REG_paid = 0.00)
+	{
+		$this->set('REG_paid', (float) $REG_paid);
+	}
+
+
+	/**
+	 *        Attendee Is Going
+	 *
+	 * @param boolean $REG_att_is_going Attendee Is Going
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function set_att_is_going($REG_att_is_going = false)
+	{
+		$this->set('REG_att_is_going', $REG_att_is_going);
+	}
+
+
+	/**
+	 * Gets the related attendee
+	 *
+	 * @return EE_Attendee|EE_Base_Class
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function attendee()
+	{
+		return EEM_Attendee::instance()->get_one_by_ID($this->attendee_ID());
+	}
+
+
+	/**
+	 * Gets the name of the attendee.
+	 *
+	 * @param bool $apply_html_entities set to true if you want to use HTML entities.
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @since 4.10.12.p
+	 */
+	public function attendeeName($apply_html_entities = false)
+	{
+		$attendee = $this->attendee();
+		if ($attendee instanceof EE_Attendee) {
+			$attendee_name = $attendee->full_name($apply_html_entities);
+		} else {
+			$attendee_name = esc_html__('Unknown', 'event_espresso');
+		}
+		return $attendee_name;
+	}
+
+
+	/**
+	 *        get Event ID
+	 */
+	public function event_ID()
+	{
+		return $this->get('EVT_ID');
+	}
+
+
+	/**
+	 *        get Event ID
+	 */
+	public function event_name()
+	{
+		$event = $this->event_obj();
+		if ($event) {
+			return $event->name();
+		} else {
+			return null;
+		}
+	}
+
+
+	/**
+	 * Fetches the event this registration is for
+	 *
+	 * @return EE_Base_Class|EE_Event
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function event_obj()
+	{
+		return EEM_Event::instance()->get_one_by_ID($this->event_ID());
+	}
+
+
+	/**
+	 *        get Attendee ID
+	 */
+	public function attendee_ID()
+	{
+		return $this->get('ATT_ID');
+	}
+
+
+	/**
+	 *        get PHP Session ID
+	 */
+	public function session_ID()
+	{
+		return $this->get('REG_session');
+	}
+
+
+	/**
+	 * Gets the string which represents the URL trigger for the receipt template in the message template system.
+	 *
+	 * @param string $messenger 'pdf' or 'html'.  Default 'html'.
+	 * @return string
+	 * @throws DomainException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function receipt_url($messenger = 'html')
+	{
+		return apply_filters('FHEE__EE_Registration__receipt_url__receipt_url', '', $this, $messenger, 'receipt');
+	}
+
+
+	/**
+	 * Gets the string which represents the URL trigger for the invoice template in the message template system.
+	 *
+	 * @param string $messenger 'pdf' or 'html'.  Default 'html'.
+	 * @return string
+	 * @throws DomainException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function invoice_url($messenger = 'html')
+	{
+		return apply_filters('FHEE__EE_Registration__invoice_url__invoice_url', '', $this, $messenger, 'invoice');
+	}
+
+
+	/**
+	 * get Registration URL Link
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function reg_url_link()
+	{
+		return (string) $this->get('REG_url_link');
+	}
+
+
+	/**
+	 * Echoes out invoice_url()
+	 *
+	 * @param string $type 'download','launch', or 'html' (default is 'launch')
+	 * @return void
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function e_invoice_url($type = 'launch')
+	{
+		echo esc_url_raw($this->invoice_url($type));
+	}
+
+
+	/**
+	 * Echoes out payment_overview_url
+	 */
+	public function e_payment_overview_url()
+	{
+		echo esc_url_raw($this->payment_overview_url());
+	}
+
+
+	/**
+	 * Gets the URL for the checkout payment options reg step
+	 * with this registration's REG_url_link added as a query parameter
+	 *
+	 * @param bool $clear_session Set to true when you want to clear the session on revisiting the
+	 *                            payment overview url.
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function payment_overview_url($clear_session = false)
+	{
+		return add_query_arg(
+			(array) apply_filters(
+				'FHEE__EE_Registration__payment_overview_url__query_args',
+				[
+					'e_reg_url_link' => $this->reg_url_link(),
+					'step'           => 'payment_options',
+					'revisit'        => true,
+					'clear_session'  => (bool) $clear_session,
+				],
+				$this
+			),
+			EE_Registry::instance()->CFG->core->reg_page_url()
+		);
+	}
+
+
+	/**
+	 * Gets the URL for the checkout attendee information reg step
+	 * with this registration's REG_url_link added as a query parameter
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function edit_attendee_information_url()
+	{
+		return add_query_arg(
+			(array) apply_filters(
+				'FHEE__EE_Registration__edit_attendee_information_url__query_args',
+				[
+					'e_reg_url_link' => $this->reg_url_link(),
+					'step'           => 'attendee_information',
+					'revisit'        => true,
+				],
+				$this
+			),
+			EE_Registry::instance()->CFG->core->reg_page_url()
+		);
+	}
+
+
+	/**
+	 * Simply generates and returns the appropriate admin_url link to edit this registration
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_admin_edit_url()
+	{
+		return EEH_URL::add_query_args_and_nonce(
+			[
+				'page'    => 'espresso_registrations',
+				'action'  => 'view_registration',
+				'_REG_ID' => $this->ID(),
+			],
+			admin_url('admin.php')
+		);
+	}
+
+
+	/**
+	 * is_primary_registrant?
+	 *
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_primary_registrant()
+	{
+		return (int) $this->get('REG_count') === 1;
+	}
+
+
+	/**
+	 * This returns the primary registration object for this registration group (which may be this object).
+	 *
+	 * @return EE_Registration
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_primary_registration()
+	{
+		if ($this->is_primary_registrant()) {
+			return $this;
+		}
+
+		// k reg_count !== 1 so let's get the EE_Registration object matching this txn_id and reg_count == 1
+		/** @var EE_Registration $primary_registrant */
+		$primary_registrant = EEM_Registration::instance()->get_one(
+			[
+				[
+					'TXN_ID'    => $this->transaction_ID(),
+					'REG_count' => 1,
+				],
+			]
+		);
+		return $primary_registrant;
+	}
+
+
+	/**
+	 * get  Attendee Number
+	 *
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function count()
+	{
+		return $this->get('REG_count');
+	}
+
+
+	/**
+	 * get Group Size
+	 *
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function group_size()
+	{
+		return $this->get('REG_group_size');
+	}
+
+
+	/**
+	 * get Registration Date
+	 *
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function date()
+	{
+		return $this->get('REG_date');
+	}
+
+
+	/**
+	 * gets a pretty date
+	 *
+	 * @param string $date_format
+	 * @param string $time_format
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function pretty_date($date_format = null, $time_format = null)
+	{
+		return $this->get_datetime('REG_date', $date_format, $time_format);
+	}
+
+
+	/**
+	 * final_price
+	 * the registration's share of the transaction total, so that the
+	 * sum of all the transaction's REG_final_prices equal the transaction's total
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function final_price(): float
+	{
+		return (float) $this->get('REG_final_price');
+	}
+
+
+	/**
+	 * pretty_final_price
+	 *  final price as formatted string, with correct decimal places and currency symbol
+	 *
+	 * @param string|null $schema
+	 *      Schemas:
+	 *      'localized_float': "3,023.00"
+	 *      'no_currency_code': "$3,023.00"
+	 *      null: "$3,023.00<span>USD</span>"
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function pretty_final_price(?string $schema = null)
+	{
+		return $this->get_pretty('REG_final_price', $schema);
+	}
+
+
+	/**
+	 * get paid (yeah)
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function paid(): float
+	{
+		return (float) $this->get('REG_paid');
+	}
+
+
+	/**
+	 * pretty_paid
+	 *
+	 * @param string|null $schema
+	 *      Schemas:
+	 *      'localized_float': "3,023.00"
+	 *      'no_currency_code': "$3,023.00"
+	 *      null: "$3,023.00<span>USD</span>"
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function pretty_paid(?string $schema = null)
+	{
+		return $this->get_pretty('REG_paid', $schema);
+	}
+
+
+	/**
+	 * owes_monies_and_can_pay
+	 * whether this registration has monies owing and it's' status allows payment
+	 *
+	 * @param array $requires_payment list of registration statuses that allow a registrant to make a payment
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function owes_monies_and_can_pay(array $requires_payment = []): bool
+	{
+		// these reg statuses require payment (if event is not free)
+		$requires_payment = ! empty($requires_payment)
+			? $requires_payment
+			: EEM_Registration::reg_statuses_that_allow_payment();
+		if (
+			$this->final_price() !== 0.0 &&
+			$this->final_price() !== $this->paid() &&
+			in_array($this->status_ID(), $requires_payment)
+		) {
+			return true;
+		}
+		return false;
+	}
+
+
+	/**
+	 * Prints out the return value of $this->pretty_status()
+	 *
+	 * @param bool $show_icons
+	 * @return void
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function e_pretty_status($show_icons = false)
+	{
+		echo wp_kses($this->pretty_status($show_icons), AllowedTags::getAllowedTags());
+	}
+
+
+	/**
+	 * Returns a nice version of the status for displaying to customers
+	 *
+	 * @param bool $show_icons
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function pretty_status($show_icons = false)
+	{
+		$status = EEM_Status::instance()->localized_status(
+			[$this->status_ID() => esc_html__('unknown', 'event_espresso')],
+			false,
+			'sentence'
+		);
+		$icon   = '';
+		switch ($this->status_ID()) {
+			case RegStatus::APPROVED:
+				$icon = $show_icons
+					? '<span class="dashicons dashicons-star-filled ee-icon-size-16 green-text"></span>'
+					: '';
+				break;
+			case RegStatus::PENDING_PAYMENT:
+				$icon = $show_icons
+					? '<span class="dashicons dashicons-star-half ee-icon-size-16 orange-text"></span>'
+					: '';
+				break;
+			case RegStatus::AWAITING_REVIEW:
+				$icon = $show_icons
+					? '<span class="dashicons dashicons-marker ee-icon-size-16 orange-text"></span>'
+					: '';
+				break;
+			case RegStatus::CANCELLED:
+				$icon = $show_icons
+					? '<span class="dashicons dashicons-no ee-icon-size-16 lt-grey-text"></span>'
+					: '';
+				break;
+			case RegStatus::INCOMPLETE:
+				$icon = $show_icons
+					? '<span class="dashicons dashicons-no ee-icon-size-16 lt-orange-text"></span>'
+					: '';
+				break;
+			case RegStatus::DECLINED:
+				$icon = $show_icons
+					? '<span class="dashicons dashicons-no ee-icon-size-16 red-text"></span>'
+					: '';
+				break;
+			case RegStatus::WAIT_LIST:
+				$icon = $show_icons
+					? '<span class="dashicons dashicons-clipboard ee-icon-size-16 purple-text"></span>'
+					: '';
+				break;
+		}
+		return $icon . $status[ $this->status_ID() ];
+	}
+
+
+	/**
+	 *        get Attendee Is Going
+	 */
+	public function att_is_going()
+	{
+		return $this->get('REG_att_is_going');
+	}
+
+
+	/**
+	 * Gets related answers
+	 *
+	 * @param array $query_params @see
+	 *                            https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return EE_Answer[]|EE_Base_Class[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function answers($query_params = [])
+	{
+		return $this->get_many_related('Answer', $query_params);
+	}
+
+
+	/**
+	 * Gets the registration's answer value to the specified question
+	 * (either the question's ID or a question object)
+	 *
+	 * @param EE_Question|int $question
+	 * @param bool            $pretty_value
+	 * @return array|string if pretty_value= true, the result will always be a string
+	 * (because the answer might be an array of answer values, so passing pretty_value=true
+	 * will convert it into some kind of string)
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function answer_value_to_question($question, $pretty_value = true)
+	{
+		$question_id = EEM_Question::instance()->ensure_is_ID($question);
+		return EEM_Answer::instance()->get_answer_value_to_question($this, $question_id, $pretty_value);
+	}
+
+
+	/**
+	 * question_groups
+	 * returns an array of EE_Question_Group objects for this registration
+	 *
+	 * @return EE_Question_Group[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function question_groups()
+	{
+		return EEM_Event::instance()->get_question_groups_for_event($this->event_ID(), $this);
+	}
+
+
+	/**
+	 * count_question_groups
+	 * returns a count of the number of EE_Question_Group objects for this registration
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function count_question_groups()
+	{
+		return EEM_Event::instance()->count_related(
+			$this->event_ID(),
+			'Question_Group',
+			[
+				[
+					'Event_Question_Group.'
+					. EEM_Event_Question_Group::instance()->fieldNameForContext($this->is_primary_registrant()) => true,
+				],
+			]
+		);
+	}
+
+
+	/**
+	 * Returns the registration date in the 'standard' string format
+	 * (function may be improved in the future to allow for different formats and timezones)
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function reg_date()
+	{
+		return $this->get_datetime('REG_date');
+	}
+
+
+	/**
+	 * Gets the datetime-ticket for this registration (ie, it can be used to isolate
+	 * the ticket this registration purchased, or the datetime they have registered
+	 * to attend)
+	 *
+	 * @return EE_Base_Class|EE_Datetime_Ticket
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function datetime_ticket()
+	{
+		return $this->get_first_related('Datetime_Ticket');
+	}
+
+
+	/**
+	 * Sets the registration's datetime_ticket.
+	 *
+	 * @param EE_Datetime_Ticket $datetime_ticket
+	 * @return EE_Base_Class|EE_Datetime_Ticket
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_datetime_ticket($datetime_ticket)
+	{
+		return $this->_add_relation_to($datetime_ticket, 'Datetime_Ticket');
+	}
+
+
+	/**
+	 * Gets deleted
+	 *
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function deleted()
+	{
+		return $this->get('REG_deleted');
+	}
+
+
+	/**
+	 * Sets deleted
+	 *
+	 * @param boolean $deleted
+	 * @return void
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function set_deleted($deleted)
+	{
+		if ($deleted) {
+			$this->delete();
+		} else {
+			$this->restore();
+		}
+	}
+
+
+	/**
+	 * Get the status object of this object
+	 *
+	 * @return EE_Base_Class|EE_Status
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function status_obj()
+	{
+		return $this->get_first_related('Status');
+	}
+
+
+	/**
+	 * Returns the number of times this registration has checked into any of the datetimes it's available for
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function count_checkins()
+	{
+		return $this->get_model()->count_related($this, 'Checkin');
+	}
+
+
+	/**
+	 * Returns the number of current Check-ins this registration is checked into for any of the datetimes the
+	 * registration is for.  Note, this is ONLY checked in (does not include checked out)
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function count_checkins_not_checkedout()
+	{
+		return $this->get_model()->count_related($this, 'Checkin', [['CHK_in' => 1]]);
+	}
+
+
+	/**
+	 * The purpose of this method is simply to check whether this registration can check in to the given datetime.
+	 *
+	 * @param int | EE_Datetime $DTT_OR_ID      The datetime the registration is being checked against
+	 * @param bool              $check_approved This is used to indicate whether the caller wants can_checkin to also
+	 *                                          consider registration status as well as datetime access.
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function can_checkin($DTT_OR_ID, $check_approved = true)
+	{
+		$DTT_ID = EEM_Datetime::instance()->ensure_is_ID($DTT_OR_ID);
+		// first check registration status
+		if (! $DTT_ID || ($check_approved && ! $this->is_approved())) {
+			return false;
+		}
+		// is there a datetime ticket that matches this dtt_ID?
+		if (
+			! (EEM_Datetime_Ticket::instance()->exists(
+				[
+					[
+						'TKT_ID' => $this->get('TKT_ID'),
+						'DTT_ID' => $DTT_ID,
+					],
+				]
+			))
+		) {
+			return false;
+		}
+
+		// final check is against TKT_uses
+		return $this->verify_can_checkin_against_TKT_uses($DTT_ID);
+	}
+
+
+	/**
+	 * This method verifies whether the user can check in for the given datetime considering the max uses value set on
+	 * the ticket. To do this,  a query is done to get the count of the datetime records already checked into.  If the
+	 * datetime given does not have a check-in record and checking in for that datetime will exceed the allowed uses,
+	 * then return false.  Otherwise return true.
+	 *
+	 * @param int | EE_Datetime $DTT_OR_ID The datetime the registration is being checked against
+	 * @return bool true means can check in.  false means cannot check in.
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function verify_can_checkin_against_TKT_uses($DTT_OR_ID)
+	{
+		$DTT_ID = EEM_Datetime::instance()->ensure_is_ID($DTT_OR_ID);
+
+		if (! $DTT_ID) {
+			return false;
+		}
+
+		$max_uses = $this->ticket() instanceof EE_Ticket
+			? $this->ticket()->uses()
+			: EE_INF;
+
+		// if max uses is not set or equals infinity then return true
+		// because it's not a factor for whether user can check in or not.
+		if (! $max_uses || $max_uses === EE_INF) {
+			return true;
+		}
+
+		// does this datetime have a check-in record?  If so, then the dtt count has already been verified so we can just
+		// go ahead and toggle.
+		if (EEM_Checkin::instance()->exists([['REG_ID' => $this->ID(), 'DTT_ID' => $DTT_ID]])) {
+			return true;
+		}
+
+		// made it here so the last check is whether the number of check-ins per unique datetime on this registration
+		// disallows further check-ins.
+		$count_unique_dtt_checkins = EEM_Checkin::instance()->count(
+			[
+				[
+					'REG_ID' => $this->ID(),
+					'CHK_in' => true,
+				],
+			],
+			'DTT_ID',
+			true
+		);
+		// check-ins have already reached their max number of uses
+		// so registrant can NOT check in
+		if ($count_unique_dtt_checkins >= $max_uses) {
+			EE_Error::add_error(
+				esc_html__(
+					'Check-in denied because number of datetime uses for the ticket has been reached or exceeded.',
+					'event_espresso'
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+			return false;
+		}
+		return true;
+	}
+
+
+	/**
+	 * toggle Check-in status for this registration
+	 * Check-ins are toggled in the following order:
+	 * never checked in -> checked in
+	 * checked in -> checked out
+	 * checked out -> checked in
+	 *
+	 * @param int  $DTT_ID  include specific datetime to toggle Check-in for.
+	 *                      If not included or null, then it is assumed latest datetime is being toggled.
+	 * @param bool $verify  If true then can_checkin() is used to verify whether the person
+	 *                      can be checked in or not.  Otherwise this forces change in check-in status.
+	 * @return bool|int     the chk_in status toggled to OR false if nothing got changed.
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function toggle_checkin_status($DTT_ID = null, $verify = false)
+	{
+		if (empty($DTT_ID)) {
+			$datetime = $this->get_latest_related_datetime();
+			$DTT_ID   = $datetime instanceof EE_Datetime ? $datetime->ID() : 0;
+			// verify the registration can check in for the given DTT_ID
+		} elseif (! $this->can_checkin($DTT_ID, $verify)) {
+			EE_Error::add_error(
+				sprintf(
+					esc_html__(
+						'The given registration (ID:%1$d) can not be checked in to the given DTT_ID (%2$d), because the registration does not have access',
+						'event_espresso'
+					),
+					$this->ID(),
+					$DTT_ID
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+			return false;
+		}
+		$status_paths = [
+			EE_Checkin::status_checked_never => EE_Checkin::status_checked_in,
+			EE_Checkin::status_checked_in    => EE_Checkin::status_checked_out,
+			EE_Checkin::status_checked_out   => EE_Checkin::status_checked_in,
+		];
+		// start by getting the current status so we know what status we'll be changing to.
+		$cur_status = $this->check_in_status_for_datetime($DTT_ID);
+		$status_to  = $status_paths[ $cur_status ];
+		// database only records true for checked IN or false for checked OUT
+		// no record ( null ) means checked in NEVER, but we obviously don't save that
+		$new_status = $status_to === EE_Checkin::status_checked_in;
+		// add relation - note Check-ins are always creating new rows
+		// because we are keeping track of Check-ins over time.
+		// Eventually we'll probably want to show a list table
+		// for the individual Check-ins so that they can be managed.
+		$checkin = EE_Checkin::new_instance(
+			[
+				'REG_ID' => $this->ID(),
+				'DTT_ID' => $DTT_ID,
+				'CHK_in' => $new_status,
+			]
+		);
+		// if the record could not be saved then return false
+		if ($checkin->save() === 0) {
+			if (WP_DEBUG) {
+				global $wpdb;
+				$error = sprintf(
+					esc_html__(
+						'Registration check in update failed because of the following database error: %1$s%2$s',
+						'event_espresso'
+					),
+					'<br />',
+					$wpdb->last_error
+				);
+			} else {
+				$error = esc_html__(
+					'Registration check in update failed because of an unknown database error',
+					'event_espresso'
+				);
+			}
+			EE_Error::add_error($error, __FILE__, __FUNCTION__, __LINE__);
+			return false;
+		}
+		// Fire a checked_in and checkout_out action.
+		$checked_status = $status_to === EE_Checkin::status_checked_in
+			? 'checked_in'
+			: 'checked_out';
+		do_action("AHEE__EE_Registration__toggle_checkin_status__{$checked_status}", $this, $DTT_ID);
+		return $status_to;
+	}
+
+
+	/**
+	 * Returns the latest datetime related to this registration (via the ticket attached to the registration).
+	 * "Latest" is defined by the `DTT_EVT_start` column.
+	 *
+	 * @return EE_Datetime|null
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_latest_related_datetime(): ?EE_Datetime
+	{
+		return EEM_Datetime::instance()->get_one(
+			[
+				[
+					'Ticket.Registration.REG_ID' => $this->ID(),
+				],
+				'order_by' => ['DTT_EVT_start' => 'DESC'],
+			]
+		);
+	}
+
+
+	/**
+	 * Returns the earliest datetime related to this registration (via the ticket attached to the registration).
+	 * "Earliest" is defined by the `DTT_EVT_start` column.
+	 *
+	 * @return EE_Base_Class|EE_Soft_Delete_Base_Class|NULL
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_earliest_related_datetime()
+	{
+		return EEM_Datetime::instance()->get_one(
+			[
+				[
+					'Ticket.Registration.REG_ID' => $this->ID(),
+				],
+				'order_by' => ['DTT_EVT_start' => 'ASC'],
+			]
+		);
+	}
+
+
+	/**
+	 * This method simply returns the check-in status for this registration and the given datetime.
+	 * If neither the datetime nor the check-in values are provided as arguments,
+	 * then this will return the LATEST check-in status for the registration across all datetimes it belongs to.
+	 *
+	 * @param int|null        $DTT_ID  The ID of the datetime we're checking against
+	 *                                 (if empty we'll get the primary datetime for
+	 *                                 this registration (via event) and use its ID);
+	 * @param EE_Checkin|null $checkin If present, we use the given check-in object rather than the dtt_id.
+	 * @return int                     Integer representing Check-in status.
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function check_in_status_for_datetime(?int $DTT_ID = 0, ?EE_Checkin $checkin = null): int
+	{
+		if ($checkin instanceof EE_Checkin) {
+			return $checkin->status();
+		}
+
+		if (! $DTT_ID) {
+			return EE_Checkin::status_invalid;
+		}
+
+		$checkin_query_params = [
+			0          => ['DTT_ID' => $DTT_ID],
+			'order_by' => ['CHK_timestamp' => 'DESC'],
+		];
+
+		$checkin = $this->get_first_related(
+			'Checkin',
+			$checkin_query_params
+		);
+		return $checkin instanceof EE_Checkin ? $checkin->status() : EE_Checkin::status_checked_never;
+	}
+
+
+	/**
+	 * This method returns a localized message for the toggled Check-in message.
+	 *
+	 * @param int|null $DTT_ID include specific datetime to get the correct Check-in message.  If not included or null,
+	 *                         then it is assumed Check-in for primary datetime was toggled.
+	 * @param bool     $error  This just flags that you want an error message returned. This is put in so that the error
+	 *                         message can be customized with the attendee name.
+	 * @return string internationalized message
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_checkin_msg(?int $DTT_ID, bool $error = false): string
+	{
+		// let's get the attendee first so we can include the name of the attendee
+		$attendee = $this->attendee();
+		if ($attendee instanceof EE_Attendee) {
+			if ($error) {
+				return sprintf(
+					esc_html__("%s's check-in status was not changed.", "event_espresso"),
+					$attendee->full_name()
+				);
+			}
+			$cur_status = $this->check_in_status_for_datetime($DTT_ID);
+			// what is the status message going to be?
+			switch ($cur_status) {
+				case EE_Checkin::status_checked_never:
+					return sprintf(
+						esc_html__('%s has been removed from Check-in records', 'event_espresso'),
+						$attendee->full_name()
+					);
+				case EE_Checkin::status_checked_in:
+					return sprintf(esc_html__('%s has been checked in', 'event_espresso'), $attendee->full_name());
+				case EE_Checkin::status_checked_out:
+					return sprintf(esc_html__('%s has been checked out', 'event_espresso'), $attendee->full_name());
+			}
+		}
+		return esc_html__('The check-in status could not be determined.', 'event_espresso');
+	}
+
+
+	/**
+	 * Returns the related EE_Transaction to this registration
+	 *
+	 * @return EE_Transaction
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws ReflectionException
+	 */
+	public function transaction(): EE_Transaction
+	{
+		$TXN_ID = $this->transaction_ID();
+		$transaction = $TXN_ID
+			? EEM_Transaction::instance()->get_one_by_ID($TXN_ID)
+			: $this->get_one_from_cache('Transaction');
+		if (! $transaction instanceof \EE_Transaction) {
+			throw new EntityNotFoundException('Transaction ID', $this->transaction_ID());
+		}
+		return $transaction;
+	}
+
+
+	/**
+	 * get Registration Code
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function reg_code(): string
+	{
+		return $this->get('REG_code')
+			?: '';
+	}
+
+
+	/**
+	 * @return mixed
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function transaction_ID()
+	{
+		return $this->get('TXN_ID');
+	}
+
+
+	/**
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function ticket_ID()
+	{
+		return $this->get('TKT_ID');
+	}
+
+
+	/**
+	 * Set Registration Code
+	 *
+	 * @param RegCode|string $REG_code Registration Code
+	 * @param boolean        $use_default
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_reg_code($REG_code, bool $use_default = false)
+	{
+		if (! $this->reg_code()) {
+			parent::set('REG_code', $REG_code, $use_default);
+		} elseif (empty($REG_code)) {
+			EE_Error::add_error(
+				esc_html__('REG_code can not be empty.', 'event_espresso'),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+		} else {
+			EE_Error::doing_it_wrong(
+				__CLASS__ . '::' . __FUNCTION__,
+				esc_html__('Can not change a registration REG_code once it has been set.', 'event_espresso'),
+				'4.6.0'
+			);
+		}
+	}
+
+
+	/**
+	 * Returns all other registrations in the same group as this registrant who have the same ticket option.
+	 * Note, if you want to just get all registrations in the same transaction (group), use:
+	 *    $registration->transaction()->registrations();
+	 *
+	 * @return EE_Registration[] or empty array if this isn't a group registration.
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @since 4.5.0
+	 */
+	public function get_all_other_registrations_in_group()
+	{
+		if ($this->group_size() < 2) {
+			return [];
+		}
+
+		$query[0] = [
+			'TXN_ID' => $this->transaction_ID(),
+			'REG_ID' => ['!=', $this->ID()],
+			'TKT_ID' => $this->ticket_ID(),
+		];
+		/** @var EE_Registration[] $registrations */
+		$registrations = $this->get_model()->get_all($query);
+		return $registrations;
+	}
+
+
+	/**
+	 * Return the link to the admin details for the object.
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_admin_details_link()
+	{
+		EE_Registry::instance()->load_helper('URL');
+		return EEH_URL::add_query_args_and_nonce(
+			[
+				'page'    => 'espresso_registrations',
+				'action'  => 'view_registration',
+				'_REG_ID' => $this->ID(),
+			],
+			admin_url('admin.php')
+		);
+	}
+
+
+	/**
+	 * Returns the link to the editor for the object.  Sometimes this is the same as the details.
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_admin_edit_link()
+	{
+		return $this->get_admin_details_link();
+	}
+
+
+	/**
+	 * Returns the link to a settings page for the object.
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_admin_settings_link()
+	{
+		return $this->get_admin_details_link();
+	}
+
+
+	/**
+	 * Returns the link to the "overview" for the object (typically the "list table" view).
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_admin_overview_link()
+	{
+		EE_Registry::instance()->load_helper('URL');
+		return EEH_URL::add_query_args_and_nonce(
+			[
+				'page' => 'espresso_registrations',
+			],
+			admin_url('admin.php')
+		);
+	}
+
+
+	/**
+	 * @param array $query_params
+	 * @return EE_Base_Class[]|EE_Registration[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function payments($query_params = [])
+	{
+		return $this->get_many_related('Payment', $query_params);
+	}
+
+
+	/**
+	 * @param array $query_params
+	 * @return EE_Base_Class[]|EE_Registration_Payment[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function registration_payments($query_params = [])
+	{
+		return $this->get_many_related('Registration_Payment', $query_params);
+	}
+
+
+	/**
+	 * This grabs the payment method corresponding to the last payment made for the amount owing on the registration.
+	 * Note: if there are no payments on the registration there will be no payment method returned.
+	 *
+	 * @return EE_Payment|EE_Payment_Method|null
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 */
+	public function payment_method()
+	{
+		return EEM_Payment_Method::instance()->get_last_used_for_registration($this);
+	}
+
+
+	/**
+	 * @return \EE_Line_Item
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function ticket_line_item()
+	{
+		$ticket            = $this->ticket();
+		$transaction       = $this->transaction();
+		$line_item         = null;
+		$ticket_line_items = \EEH_Line_Item::get_line_items_by_object_type_and_IDs(
+			$transaction->total_line_item(),
+			'Ticket',
+			[$ticket->ID()]
+		);
+		foreach ($ticket_line_items as $ticket_line_item) {
+			if (
+				$ticket_line_item instanceof \EE_Line_Item
+				&& $ticket_line_item->OBJ_type() === 'Ticket'
+				&& $ticket_line_item->OBJ_ID() === $ticket->ID()
+			) {
+				$line_item = $ticket_line_item;
+				break;
+			}
+		}
+		if (! ($line_item instanceof \EE_Line_Item && $line_item->OBJ_type() === 'Ticket')) {
+			throw new EntityNotFoundException('Line Item Ticket ID', $ticket->ID());
+		}
+		return $line_item;
+	}
+
+
+	/**
+	 * Soft Deletes this model object.
+	 *
+	 * @param string $source function name that called this method
+	 * @return boolean | int
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function delete()
+	{
+		if ($this->update_extra_meta(EE_Registration::PRE_TRASH_REG_STATUS_KEY, $this->status_ID()) === true) {
+			$this->set_status(
+				RegStatus::CANCELLED,
+				false,
+				new Context(
+					__METHOD__,
+					esc_html__('Executed when a registration is trashed.', 'event_espresso')
+				)
+			);
+		}
+		return parent::delete();
+	}
+
+
+	/**
+	 * Restores whatever the previous status was on a registration before it was trashed (if possible)
+	 *
+	 * @param string $source function name that called this method
+	 * @return bool|int
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function restore()
+	{
+		$previous_status = $this->get_extra_meta(
+			EE_Registration::PRE_TRASH_REG_STATUS_KEY,
+			true,
+			RegStatus::CANCELLED
+		);
+		if ($previous_status) {
+			$this->delete_extra_meta(EE_Registration::PRE_TRASH_REG_STATUS_KEY);
+			$this->set_status(
+				$previous_status,
+				false,
+				new Context(
+					__METHOD__,
+					esc_html__('Executed when a trashed registration is restored.', 'event_espresso')
+				)
+			);
+		}
+		return parent::restore();
+	}
+
+
+	/**
+	 * possibly toggle Registration status based on comparison of REG_paid vs REG_final_price
+	 *
+	 * @param boolean $trigger_set_status_logic  EE_Registration::set_status() can trigger additional logic
+	 *                                           depending on whether the reg status changes to or from "Approved"
+	 * @return boolean whether the Registration status was updated
+	 * @throws DomainException
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws UnexpectedEntityException
+	 */
+	public function updateStatusBasedOnTotalPaid($trigger_set_status_logic = true)
+	{
+		$paid  = $this->paid();
+		$price = $this->final_price();
+		switch (true) {
+			// overpaid or paid
+			case EEH_Money::compare_floats($paid, $price, '>'):
+			case EEH_Money::compare_floats($paid, $price):
+				$new_status = RegStatus::APPROVED;
+				break;
+			//  underpaid
+			case EEH_Money::compare_floats($paid, $price, '<'):
+				$new_status = RegStatus::PENDING_PAYMENT;
+				break;
+			// uhhh Houston...
+			default:
+				throw new RuntimeException(
+					esc_html__('The total paid calculation for this registration is inaccurate.', 'event_espresso')
+				);
+		}
+		if ($new_status !== $this->status_ID()) {
+			if ($trigger_set_status_logic) {
+				return $this->set_status(
+					$new_status,
+					false,
+					new Context(
+						__METHOD__,
+						esc_html__(
+							'Executed when the registration status is updated based on total paid.',
+							'event_espresso'
+						)
+					)
+				);
+			}
+			parent::set('STS_ID', $new_status);
+			return true;
+		}
+		return false;
+	}
+
+
+	/*************************** DEPRECATED ***************************/
+
+
+	/**
+	 * @deprecated
+	 * @since     4.7.0
+	 */
+	public function price_paid()
+	{
+		EE_Error::doing_it_wrong(
+			'EE_Registration::price_paid()',
+			esc_html__(
+				'This method is deprecated, please use EE_Registration::final_price() instead.',
+				'event_espresso'
+			),
+			'4.7.0'
+		);
+		return $this->final_price();
+	}
+
+
+	/**
+	 * @param float $REG_final_price
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 * @throws DomainException
+	 * @deprecated
+	 * @since     4.7.0
+	 */
+	public function set_price_paid($REG_final_price = 0.00)
+	{
+		EE_Error::doing_it_wrong(
+			'EE_Registration::set_price_paid()',
+			esc_html__(
+				'This method is deprecated, please use EE_Registration::set_final_price() instead.',
+				'event_espresso'
+			),
+			'4.7.0'
+		);
+		$this->set_final_price($REG_final_price);
+	}
+
+
+	/**
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @deprecated
+	 * @since 4.7.0
+	 */
+	public function pretty_price_paid()
+	{
+		EE_Error::doing_it_wrong(
+			'EE_Registration::pretty_price_paid()',
+			esc_html__(
+				'This method is deprecated, please use EE_Registration::pretty_final_price() instead.',
+				'event_espresso'
+			),
+			'4.7.0'
+		);
+		return $this->pretty_final_price();
+	}
+
+
+	/**
+	 * Gets the primary datetime related to this registration via the related Event to this registration
+	 *
+	 * @return EE_Datetime
+	 * @throws EE_Error
+	 * @throws EntityNotFoundException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @deprecated 4.9.17
+	 */
+	public function get_related_primary_datetime()
+	{
+		EE_Error::doing_it_wrong(
+			__METHOD__,
+			esc_html__(
+				'Use EE_Registration::get_latest_related_datetime() or EE_Registration::get_earliest_related_datetime()',
+				'event_espresso'
+			),
+			'4.9.17',
+			'5.0.0'
+		);
+		return $this->event()->primary_datetime();
+	}
+
+
+	/**
+	 * Returns the contact's name (or "Unknown" if there is no contact.)
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @since 4.10.12.p
+	 */
+	public function name()
+	{
+		return $this->attendeeName();
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function wasMoved(): bool
+	{
+		// only need to check 'registration-moved-to' because
+		// the existence of a new REG ID means the registration was moved
+		$reg_moved = $this->get_extra_meta('registration-moved-to', true, []);
+		return isset($reg_moved['NEW_REG_ID']) && $reg_moved['NEW_REG_ID'];
+	}
+
+
+	/**
+	 * @param EE_Payment $payment
+	 * @param float|null $amount
+	 * @return float
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since 5.0.8.p
+	 */
+	public function applyPayment(EE_Payment $payment, ?float $amount = null): float
+	{
+		$payment_amount = $amount ?? $payment->amount();
+		// ensure $payment_amount is NOT negative
+		$payment_amount = (float) abs($payment_amount);
+		$payment_amount = $payment->is_a_refund()
+			? $this->processRefund($payment_amount)
+			: $this->processPayment($payment_amount);
+		if ($payment_amount) {
+			$reg_payment = EEM_Registration_Payment::instance()->get_one(
+				[['REG_ID' => $this->ID(), 'PAY_ID' => $payment->ID()]]
+			);
+			// if existing registration payment exists
+			if ($reg_payment instanceof EE_Registration_Payment) {
+				// then update that record
+				$reg_payment->set_amount($payment_amount);
+			} else {
+				// or add new relation between registration and payment and set amount
+				$reg_payment = EE_Registration_Payment::new_instance(
+					[
+						'REG_ID'     => $this->ID(),
+						'PAY_ID'     => $payment->ID(),
+						'RPY_amount' => $payment_amount,
+					]
+				);
+			}
+			$reg_payment->save();
+		}
+		return $payment_amount;
+	}
+
+
+	/**
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	private function processPayment(float $payment_amount): float
+	{
+		$paid  = $this->paid();
+		$owing = $this->final_price() - $paid;
+		if ($owing <= 0) {
+			return 0.0;
+		}
+		// don't allow payment amount to exceed the incoming amount, OR the amount owing
+		$payment_amount = min($payment_amount, $owing);
+		$paid           = $paid + $payment_amount;
+		// calculate and set new REG_paid
+		$this->set_paid($paid);
+		// make it stick
+		$this->save();
+		return (float) $payment_amount;
+	}
+
+
+	/**
+	 * @throws ReflectionException
+	 * @throws EE_Error
+	 */
+	private function processRefund(float $payment_amount): float
+	{
+		$paid = $this->paid();
+		if ($paid <= 0) {
+			return 0.0;
+		}
+		// don't allow refund amount to exceed the incoming amount, OR the amount paid
+		$payment_amount = min($payment_amount, $paid);
+		// calculate and set new REG_paid
+		$paid = $paid - $payment_amount;
+		$this->set_paid($paid);
+		// make it stick
+		$this->save();
+		// convert payment amount back to a negative value for storage in the db
+		return (float) $payment_amount;
+	}
+
+
+	/**
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since 5.0.20.p
+	 */
+	public function defaultRegistrationStatus(): string
+	{
+		$default_event_reg_status = $this->event()->default_registration_status();
+		$default_reg_status = (string) apply_filters(
+			'AFEE__EE_Registration__defaultRegistrationStatus__default_reg_status',
+			$default_event_reg_status,
+			$this
+		);
+		return RegStatus::isValidStatus($default_reg_status, false)
+			? $default_reg_status
+			: $default_event_reg_status;
+	}
 }

Spacing +18 added lines, -18 removed lines

@@ -137,7 +137,7 @@ 
     {
         switch ($field_name) {
             case 'REG_code':
-                if (! empty($field_value) && ! $this->reg_code()) {
+                if ( ! empty($field_value) && ! $this->reg_code()) {
                     $this->set_reg_code($field_value, $use_default);
                 }
                 break;
@@ -184,7 +184,7 @@ 
             $this
         );
         // it's still good to allow the parent set method to have a say
-        parent::set('STS_ID', (! empty($new_STS_ID) ? $new_STS_ID : null), $use_default);
+        parent::set('STS_ID', ( ! empty($new_STS_ID) ? $new_STS_ID : null), $use_default);
         // if status has changed
         if (
             $old_STS_ID !== $new_STS_ID // and that status has actually changed
@@ -436,7 +436,7 @@ 
     public function event(): EE_Event
     {
         $event = $this->event_obj();
-        if (! $event instanceof EE_Event) {
+        if ( ! $event instanceof EE_Event) {
             throw new EntityNotFoundException('Event ID', $this->event_ID());
         }
         return $event;
@@ -479,7 +479,7 @@ 
     {
         // reserved ticket and datetime counts will be decremented as sold counts are incremented
         // so stop tracking that this reg has a ticket reserved
-        $this->release_reserved_ticket(false, "REG: {$this->ID()} (ln:" . __LINE__ . ')');
+        $this->release_reserved_ticket(false, "REG: {$this->ID()} (ln:".__LINE__.')');
         $ticket = $this->ticket();
         $ticket->increaseSold();
         // possibly set event status to sold out
@@ -529,7 +529,7 @@ 
             $reserved = $this->update_extra_meta(EE_Registration::HAS_RESERVED_TICKET_KEY, true);
             if ($reserved && $update_ticket) {
                 $ticket = $this->ticket();
-                $ticket->increaseReserved(1, "REG: {$this->ID()} (ln:" . __LINE__ . ')');
+                $ticket->increaseReserved(1, "REG: {$this->ID()} (ln:".__LINE__.')');
                 $this->update_extra_meta('reserve_ticket', "{$this->ticket_ID()} from {$source}");
                 $ticket->save();
             }
@@ -557,7 +557,7 @@ 
             $reserved = $this->update_extra_meta(EE_Registration::HAS_RESERVED_TICKET_KEY, false);
             if ($reserved && $update_ticket) {
                 $ticket = $this->ticket();
-                $ticket->decreaseReserved(1, true, "REG: {$this->ID()} (ln:" . __LINE__ . ')');
+                $ticket->decreaseReserved(1, true, "REG: {$this->ID()} (ln:".__LINE__.')');
                 $this->update_extra_meta('release_reserved_ticket', "{$this->ticket_ID()} from {$source}");
             }
         }
@@ -1367,7 +1367,7 @@ 
             false,
             'sentence'
         );
-        $icon   = '';
+        $icon = '';
         switch ($this->status_ID()) {
             case RegStatus::APPROVED:
                 $icon = $show_icons
@@ -1405,7 +1405,7 @@ 
                     : '';
                 break;
         }
-        return $icon . $status[ $this->status_ID() ];
+        return $icon.$status[$this->status_ID()];
     }
 
 
@@ -1660,7 +1660,7 @@ 
     {
         $DTT_ID = EEM_Datetime::instance()->ensure_is_ID($DTT_OR_ID);
         // first check registration status
-        if (! $DTT_ID || ($check_approved && ! $this->is_approved())) {
+        if ( ! $DTT_ID || ($check_approved && ! $this->is_approved())) {
             return false;
         }
         // is there a datetime ticket that matches this dtt_ID?
@@ -1700,7 +1700,7 @@ 
     {
         $DTT_ID = EEM_Datetime::instance()->ensure_is_ID($DTT_OR_ID);
 
-        if (! $DTT_ID) {
+        if ( ! $DTT_ID) {
             return false;
         }
 
@@ -1710,7 +1710,7 @@ 
 
         // if max uses is not set or equals infinity then return true
         // because it's not a factor for whether user can check in or not.
-        if (! $max_uses || $max_uses === EE_INF) {
+        if ( ! $max_uses || $max_uses === EE_INF) {
             return true;
         }
 
@@ -1774,7 +1774,7 @@ 
             $datetime = $this->get_latest_related_datetime();
             $DTT_ID   = $datetime instanceof EE_Datetime ? $datetime->ID() : 0;
             // verify the registration can check in for the given DTT_ID
-        } elseif (! $this->can_checkin($DTT_ID, $verify)) {
+        } elseif ( ! $this->can_checkin($DTT_ID, $verify)) {
             EE_Error::add_error(
                 sprintf(
                     esc_html__(
@@ -1797,7 +1797,7 @@ 
         ];
         // start by getting the current status so we know what status we'll be changing to.
         $cur_status = $this->check_in_status_for_datetime($DTT_ID);
-        $status_to  = $status_paths[ $cur_status ];
+        $status_to  = $status_paths[$cur_status];
         // database only records true for checked IN or false for checked OUT
         // no record ( null ) means checked in NEVER, but we obviously don't save that
         $new_status = $status_to === EE_Checkin::status_checked_in;
@@ -1909,7 +1909,7 @@ 
             return $checkin->status();
         }
 
-        if (! $DTT_ID) {
+        if ( ! $DTT_ID) {
             return EE_Checkin::status_invalid;
         }
 
@@ -1980,7 +1980,7 @@ 
         $transaction = $TXN_ID
             ? EEM_Transaction::instance()->get_one_by_ID($TXN_ID)
             : $this->get_one_from_cache('Transaction');
-        if (! $transaction instanceof \EE_Transaction) {
+        if ( ! $transaction instanceof \EE_Transaction) {
             throw new EntityNotFoundException('Transaction ID', $this->transaction_ID());
         }
         return $transaction;
@@ -2045,7 +2045,7 @@ 
      */
     public function set_reg_code($REG_code, bool $use_default = false)
     {
-        if (! $this->reg_code()) {
+        if ( ! $this->reg_code()) {
             parent::set('REG_code', $REG_code, $use_default);
         } elseif (empty($REG_code)) {
             EE_Error::add_error(
@@ -2056,7 +2056,7 @@ 
             );
         } else {
             EE_Error::doing_it_wrong(
-                __CLASS__ . '::' . __FUNCTION__,
+                __CLASS__.'::'.__FUNCTION__,
                 esc_html__('Can not change a registration REG_code once it has been set.', 'event_espresso'),
                 '4.6.0'
             );
@@ -2247,7 +2247,7 @@ 
                 break;
             }
         }
-        if (! ($line_item instanceof \EE_Line_Item && $line_item->OBJ_type() === 'Ticket')) {
+        if ( ! ($line_item instanceof \EE_Line_Item && $line_item->OBJ_type() === 'Ticket')) {
             throw new EntityNotFoundException('Line Item Ticket ID', $ticket->ID());
         }
         return $line_item;

core/db_classes/EE_Line_Item.class.php

Indentation +1737 added lines, -1737 removed lines

@@ -16,1741 +16,1741 @@
  */
 class EE_Line_Item extends EE_Base_Class
 {
-    /**
-     * for children line items (currently not a normal relation)
-     *
-     * @var EE_Line_Item[]
-     */
-    protected array $_children = [];
-
-    /**
-     * query params used to obtain children line items above
-     *
-     * @var array
-     */
-    private array $children_query_params = [];
-
-    /**
-     * for the parent line item
-     *
-     * @var EE_Line_Item|null
-     */
-    protected ?EE_Line_Item $_parent = null;
-
-    /**
-     * @var LineItemCalculator
-     */
-    protected LineItemCalculator $calculator;
-
-
-    /**
-     * @param array       $props_n_values incoming values
-     * @param string|null $timezone       incoming timezone as set by the model.
-     *                                    If not set the timezone for the website will be used.
-     * @param array       $date_formats   incoming date_formats in an array where the first value is the
-     *                                    date_format and the second value is the time format
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function new_instance(
-        array $props_n_values = [],
-        ?string $timezone = '',
-        array $date_formats = []
-    ): EE_Line_Item {
-        $has_object = parent::_check_for_object(
-            $props_n_values,
-            __CLASS__,
-            $timezone,
-            $date_formats
-        );
-        return $has_object ?: new self($props_n_values, false, $timezone);
-    }
-
-
-    /**
-     * @param array       $props_n_values incoming values from the database
-     * @param string|null $timezone       incoming timezone as set by the model.
-     *                                    If not set the timezone for the website will be used.
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public static function new_instance_from_db(array $props_n_values = [], ?string $timezone = ''): EE_Line_Item
-    {
-        return new self($props_n_values, true, $timezone);
-    }
-
-
-    /**
-     * Adds some defaults if they're not specified
-     *
-     * @param array  $fieldValues
-     * @param bool   $bydb
-     * @param string $timezone
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    protected function __construct($fieldValues = [], $bydb = false, $timezone = '')
-    {
-        $this->calculator = LoaderFactory::getShared(LineItemCalculator::class);
-        parent::__construct($fieldValues, $bydb, $timezone);
-        if (! $this->get('LIN_code')) {
-            $this->set_code($this->generate_code());
-        }
-    }
-
-
-    public function __wakeup()
-    {
-        $this->calculator = LoaderFactory::getShared(LineItemCalculator::class);
-        parent::__wakeup();
-    }
-
-
-    /**
-     * Gets ID
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function ID(): int
-    {
-        return (int) $this->get('LIN_ID');
-    }
-
-
-    /**
-     * Gets TXN_ID
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function TXN_ID(): int
-    {
-        return (int) $this->get('TXN_ID');
-    }
-
-
-    /**
-     * Sets TXN_ID
-     *
-     * @param int $TXN_ID
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_TXN_ID(int $TXN_ID)
-    {
-        $this->set('TXN_ID', $TXN_ID);
-    }
-
-
-    /**
-     * Gets name
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function name(): string
-    {
-        $name = (string) $this->get('LIN_name');
-        if (! $name) {
-            $name = ucwords(str_replace('-', ' ', $this->type()));
-        }
-        return $name;
-    }
-
-
-    /**
-     * Sets name
-     *
-     * @param string $name
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_name(string $name)
-    {
-        $this->set('LIN_name', $name);
-    }
-
-
-    /**
-     * Gets desc
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function desc(): string
-    {
-        return (string) $this->get('LIN_desc');
-    }
-
-
-    /**
-     * Sets desc
-     *
-     * @param string $desc
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_desc(string $desc)
-    {
-        $this->set('LIN_desc', $desc);
-    }
-
-
-    /**
-     * Gets quantity
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function quantity(): int
-    {
-        return (int) $this->get('LIN_quantity');
-    }
-
-
-    /**
-     * Sets quantity
-     *
-     * @param int $quantity
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_quantity(int $quantity)
-    {
-        $this->set('LIN_quantity', max($quantity, 0));
-    }
-
-
-    /**
-     * Gets item_id
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function OBJ_ID(): int
-    {
-        return (int) $this->get('OBJ_ID');
-    }
-
-
-    /**
-     * Sets item_id
-     *
-     * @param int $item_id
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_OBJ_ID(int $item_id)
-    {
-        $this->set('OBJ_ID', $item_id);
-    }
-
-
-    /**
-     * Gets item_type
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function OBJ_type(): string
-    {
-        return (string) $this->get('OBJ_type');
-    }
-
-
-    /**
-     * Gets item_type
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function OBJ_type_i18n(): string
-    {
-        $obj_type = $this->OBJ_type();
-        switch ($obj_type) {
-            case EEM_Line_Item::OBJ_TYPE_EVENT:
-                $obj_type = esc_html__('Event', 'event_espresso');
-                break;
-            case EEM_Line_Item::OBJ_TYPE_PRICE:
-                $obj_type = esc_html__('Price', 'event_espresso');
-                break;
-            case EEM_Line_Item::OBJ_TYPE_PROMOTION:
-                $obj_type = esc_html__('Promotion', 'event_espresso');
-                break;
-            case EEM_Line_Item::OBJ_TYPE_TICKET:
-                $obj_type = esc_html__('Ticket', 'event_espresso');
-                break;
-            case EEM_Line_Item::OBJ_TYPE_TRANSACTION:
-                $obj_type = esc_html__('Transaction', 'event_espresso');
-                break;
-        }
-        return (string) apply_filters('FHEE__EE_Line_Item__OBJ_type_i18n', $obj_type, $this);
-    }
-
-
-    /**
-     * Sets item_type
-     *
-     * @param string $OBJ_type
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_OBJ_type(string $OBJ_type)
-    {
-        $this->set('OBJ_type', $OBJ_type);
-    }
-
-
-    /**
-     * Gets unit_price
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function unit_price(): float
-    {
-        return (float) $this->get('LIN_unit_price');
-    }
-
-
-    /**
-     * Sets unit_price
-     *
-     * @param int|float $unit_price
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_unit_price($unit_price)
-    {
-        $this->set('LIN_unit_price', (float) $unit_price);
-    }
-
-
-    /**
-     * Checks if this item is a percentage modifier or not
-     *
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_percent(): bool
-    {
-        if ($this->is_tax_sub_total()) {
-            // tax subtotals HAVE a percent on them, that percentage only applies
-            // to taxable items, so it's an exception. Treat it like a flat line item
-            return false;
-        }
-        $unit_price = abs($this->get('LIN_unit_price'));
-        $percent    = abs($this->get('LIN_percent'));
-        if ($unit_price < .001 && $percent) {
-            return true;
-        }
-        if ($unit_price >= .001 && ! $percent) {
-            return false;
-        }
-        if ($unit_price >= .001 && $percent) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'A Line Item can not have a unit price of (%s) AND a percent (%s)!',
-                        'event_espresso'
-                    ),
-                    $unit_price,
-                    $percent
-                )
-            );
-        }
-        // if they're both 0, assume it's not a percent item
-        return false;
-    }
-
-
-    /**
-     * Gets percent (between 100-.001)
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function percent(): float
-    {
-        return (float) $this->get('LIN_percent');
-    }
-
-
-    /**
-     * @return string
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since 5.0.0.p
-     */
-    public function prettyPercent(): string
-    {
-        return (string) $this->get_pretty('LIN_percent');
-    }
-
-
-    /**
-     * Sets percent (between 100-0.01)
-     *
-     * @param int|float $percent
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_percent($percent)
-    {
-        $this->set('LIN_percent', (float) $percent);
-    }
-
-
-    /**
-     * Gets total
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function pretaxTotal(): float
-    {
-        return (float) $this->get('LIN_pretax');
-    }
-
-
-    /**
-     * Sets total
-     *
-     * @param int|float $pretax_total
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function setPretaxTotal($pretax_total)
-    {
-        $this->set('LIN_pretax', (float) $pretax_total);
-    }
-
-
-    /**
-     * @return float
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since  5.0.0.p
-     */
-    public function totalWithTax(): float
-    {
-        return (float) $this->get('LIN_total');
-    }
-
-
-    /**
-     * Sets total
-     *
-     * @param int|float $total
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since  5.0.0.p
-     */
-    public function setTotalWithTax($total)
-    {
-        $this->set('LIN_total', (float) $total);
-    }
-
-
-    /**
-     * Gets total
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @deprecatd 5.0.0.p
-     */
-    public function total(): float
-    {
-        return $this->totalWithTax();
-    }
-
-
-    /**
-     * Sets total
-     *
-     * @param int|float $total
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @deprecatd 5.0.0.p
-     */
-    public function set_total($total)
-    {
-        $this->setTotalWithTax((float) $total);
-    }
-
-
-    /**
-     * Gets order
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function order(): int
-    {
-        return (int) $this->get('LIN_order');
-    }
-
-
-    /**
-     * Sets order
-     *
-     * @param int $order
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_order(int $order)
-    {
-        $this->set('LIN_order', $order);
-    }
-
-
-    /**
-     * Gets parent
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function parent_ID(): int
-    {
-        return (int) $this->get('LIN_parent');
-    }
-
-
-    /**
-     * Sets parent
-     *
-     * @param int $parent
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_parent_ID(int $parent)
-    {
-        $this->set('LIN_parent', $parent);
-    }
-
-
-    /**
-     * Gets type
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function type(): string
-    {
-        return (string) $this->get('LIN_type');
-    }
-
-
-    /**
-     * Sets type
-     *
-     * @param string $type
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_type(string $type)
-    {
-        $this->set('LIN_type', $type);
-    }
-
-
-    /**
-     * Gets the line item of which this item is a composite. Eg, if this is a subtotal, the parent might be a total\
-     * If this line item is saved to the DB, fetches the parent from the DB. However, if this line item isn't in the DB
-     * it uses its cached reference to its parent line item (which would have been set by `EE_Line_Item::set_parent()`
-     * or indirectly by `EE_Line_item::add_child_line_item()`)
-     *
-     * @return EE_Line_Item|null
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function parent(): ?EE_Line_Item
-    {
-        if (! $this->_parent instanceof EE_Line_Item) {
-            $this->_parent = $this->ID()
-                ? $this->get_model()->get_one_by_ID($this->parent_ID())
-                : $this->_parent;
-        }
-        return $this->_parent;
-    }
-
-
-    /**
-     * Gets ALL the children of this line item (ie, all the parts that contribute towards this total).
-     *
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function children(array $query_params = []): array
-    {
-        // check if the query params have changed since the last time we ran this query
-        $new_params = ! empty(EEH_Array::array_diff_recursive($query_params, $this->children_query_params));
-        if (($new_params || empty($this->_children)) && $this->ID()) {
-            $this->children_query_params = $query_params;
-            // ensure where params are an array
-            $query_params[0] = isset($query_params[0]) && is_array($query_params[0]) ? $query_params[0] : [];
-            // add defaults for line item parent and orderby
-            $query_params[0] += ['LIN_parent' => $this->ID()];
-            $query_params    += ['order_by' => ['LIN_order' => 'ASC']];
-            $children = $this->get_model()->get_all($query_params);
-            foreach ($children as $child) {
-                if ($child instanceof EE_Line_Item) {
-                    $this->addLineItemToChildren($child);
-                }
-            }
-        }
-        return $this->_children;
-    }
-
-
-    private function addLineItemToChildren($child_line_item)
-    {
-        $this->_children[ $child_line_item->code() ] = $child_line_item;
-    }
-
-
-    private function getChildLineItemFromCache(string $code): ?EE_Line_Item
-    {
-        return $this->_children[ $code ] ?? null;
-    }
-
-
-    private function removeChildLineItemFromCache(string $code): int
-    {
-        if (isset($this->_children[ $code ])) {
-            unset($this->_children[ $code ]);
-            return 1;
-        }
-        return 0;
-    }
-
-
-    private function resetChildren()
-    {
-        $this->_children = [];
-    }
-
-
-    /**
-     * Gets code
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function code(): string
-    {
-        return (string) $this->get('LIN_code');
-    }
-
-
-    /**
-     * Sets code
-     *
-     * @param string $code
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_code(string $code)
-    {
-        $this->set('LIN_code', $code);
-    }
-
-
-    /**
-     * Gets is_taxable
-     *
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_taxable(): bool
-    {
-        return (bool) $this->get('LIN_is_taxable');
-    }
-
-
-    /**
-     * Sets is_taxable
-     *
-     * @param bool $is_taxable
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_is_taxable(bool $is_taxable)
-    {
-        $this->set('LIN_is_taxable', $is_taxable);
-    }
-
-
-    /**
-     * @param int $timestamp
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since 5.0.0.p
-     */
-    public function setTimestamp(int $timestamp)
-    {
-        $this->set('LIN_timestamp', $timestamp);
-    }
-
-
-    /**
-     * Gets the object that this model-joins-to.
-     * returns one of the model objects that the field OBJ_ID can point to... see the 'OBJ_ID' field on
-     * EEM_Promotion_Object
-     *        Eg, if this line item join model object is for a ticket, this will return the EE_Ticket object
-     *
-     * @return EE_Base_Class|null
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_object(): ?EE_Base_Class
-    {
-        $model_name_of_related_obj = $this->OBJ_type();
-        return $this->get_model()->has_relation($model_name_of_related_obj)
-            ? $this->get_first_related($model_name_of_related_obj)
-            : null;
-    }
-
-
-    /**
-     * Like EE_Line_Item::get_object(), but can only ever actually return an EE_Ticket.
-     * (IE, if this line item is for a price or something else, will return NULL)
-     *
-     * @param array $query_params deprecated 5.0.12.p
-     * @return EE_Ticket|null
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function ticket(array $query_params = []): ?EE_Ticket
-    {
-        // we're going to assume that when this method is called
-        // we always want to receive the attached ticket EVEN if that ticket is archived.
-        if(! $this->OBJ_ID() || $this->OBJ_type() !== EEM_Line_Item::OBJ_TYPE_TICKET) {
-            return null;
-        }
-        if(empty($query_args)) {
-            return EEM_Ticket::instance()->get_one_by_ID($this->OBJ_ID());
-        }
-        // legacy usage
-        $query_params += ['default_where_conditions' => 'none'];
-        return $this->get_first_related(EEM_Line_Item::OBJ_TYPE_TICKET, $query_params);
-    }
-
-
-    /**
-     * Gets the EE_Datetime that's related to the ticket, IF this is for a ticket
-     *
-     * @return EE_Datetime|null
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_ticket_datetime(): ?EE_Datetime
-    {
-        if ($this->OBJ_type() === EEM_Line_Item::OBJ_TYPE_TICKET) {
-            $ticket = $this->ticket();
-            if ($ticket instanceof EE_Ticket) {
-                $datetime = $ticket->first_datetime();
-                if ($datetime instanceof EE_Datetime) {
-                    return $datetime;
-                }
-            }
-        }
-        return null;
-    }
-
-
-    /**
-     * Gets the event's name that's related to the ticket, if this is for
-     * a ticket
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function ticket_event_name(): string
-    {
-        $event_name = esc_html__('Unknown', 'event_espresso');
-        $event      = $this->ticket_event();
-        if ($event instanceof EE_Event) {
-            $event_name = $event->name();
-        }
-        return $event_name;
-    }
-
-
-    /**
-     * Gets the event that's related to the ticket, if this line item represents a ticket.
-     *
-     * @return EE_Event|null
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function ticket_event(): ?EE_Event
-    {
-        $event  = null;
-        $ticket = $this->ticket();
-        if ($ticket instanceof EE_Ticket) {
-            $datetime = $ticket->first_datetime();
-            if ($datetime instanceof EE_Datetime) {
-                $event = $datetime->event();
-            }
-        }
-        return $event;
-    }
-
-
-    /**
-     * Gets the first datetime for this lien item, assuming it's for a ticket
-     *
-     * @param string $date_format
-     * @param string $time_format
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function ticket_datetime_start(string $date_format = '', string $time_format = ''): string
-    {
-        $first_datetime_string = esc_html__('Unknown', 'event_espresso');
-        $datetime              = $this->get_ticket_datetime();
-        if ($datetime) {
-            $first_datetime_string = $datetime->start_date_and_time($date_format, $time_format);
-        }
-        return $first_datetime_string;
-    }
-
-
-    /**
-     * Adds the line item as a child to this line item. If there is another child line
-     * item with the same LIN_code, it is overwritten by this new one
-     *
-     * @param EE_Line_Item $line_item
-     * @param bool         $set_order
-     * @return bool success
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function add_child_line_item(EE_Line_Item $line_item, bool $set_order = true): bool
-    {
-        // should we calculate the LIN_order for this line item ?
-        if ($set_order || $line_item->order() === null) {
-            $line_item->set_order(count($this->children()));
-        }
-        if ($this->ID()) {
-            // check for any duplicate line items (with the same code), if so, this replaces it
-            $line_item_with_same_code = $this->get_child_line_item($line_item->code());
-            if ($line_item_with_same_code instanceof EE_Line_Item && $line_item_with_same_code !== $line_item) {
-                $this->delete_child_line_item($line_item_with_same_code->code());
-            }
-            $line_item->set_parent_ID($this->ID());
-            if ($this->TXN_ID()) {
-                $line_item->set_TXN_ID($this->TXN_ID());
-            }
-            $this->addLineItemToChildren($line_item);
-            return (bool) $line_item->save();
-        }
-        $this->addLineItemToChildren($line_item);
-        if ($line_item->parent() !== $this) {
-            $line_item->set_parent($this);
-        }
-        return true;
-    }
-
-
-    /**
-     * Similar to EE_Base_Class::_add_relation_to, except this isn't a normal relation.
-     * If this line item is saved to the DB, this is just a wrapper for set_parent_ID() and save()
-     * However, if this line item is NOT saved to the DB, this just caches the parent on
-     * the EE_Line_Item::_parent property.
-     *
-     * @param EE_Line_Item $line_item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function set_parent(EE_Line_Item $line_item)
-    {
-        if ($this->ID()) {
-            if (! $line_item->ID()) {
-                $line_item->save();
-            }
-            $this->set_parent_ID($line_item->ID());
-            $this->save();
-        } else {
-            $this->_parent = $line_item;
-            $this->set_parent_ID($line_item->ID());
-        }
-    }
-
-
-    /**
-     * Gets the child line item as specified by its code. Because this returns an object (by reference)
-     * you can modify this child line item and the parent (this object) can know about them
-     * because it also has a reference to that line item
-     *
-     * @param string $code
-     * @return EE_Base_Class|EE_Line_Item|EE_Soft_Delete_Base_Class|NULL
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_child_line_item(string $code)
-    {
-        $child = $this->getChildLineItemFromCache($code);
-        if ($child instanceof EE_Line_Item) {
-            return $child;
-        }
-        if ($this->ID()) {
-            return $this->get_model()->get_one(
-                [['LIN_parent' => $this->ID(), 'LIN_code' => $code]]
-            );
-        }
-        return null;
-    }
-
-
-    /**
-     * Returns how many items are deleted (or, if this item has not been saved ot the DB yet, just how many it HAD
-     * cached on it)
-     *
-     * @return int
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function delete_children_line_items(): int
-    {
-        $count = count($this->_children);
-        $this->resetChildren();
-        return $this->ID() ? (int) $this->get_model()->delete([['LIN_parent' => $this->ID()]]) : $count;
-    }
-
-
-    /**
-     * If this line item has been saved to the DB, deletes its child with LIN_code == $code. If this line
-     * HAS NOT been saved to the DB, removes the child line item with index $code.
-     * Also searches through the child's children for a matching line item. However, once a line item has been found
-     * and deleted, stops searching (so if there are line items with duplicate codes, only the first one found will be
-     * deleted)
-     *
-     * @param string $code
-     * @param bool   $stop_search_once_found
-     * @return int count of items deleted (or simply removed from the line item's cache, if not has not been saved to
-     *             the DB yet)
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function delete_child_line_item(string $code, bool $stop_search_once_found = true): int
-    {
-        $removed = $this->removeChildLineItemFromCache($code);
-        if ($this->ID()) {
-            $items_deleted = 0;
-            if ($this->code() === $code) {
-                $items_deleted += EEH_Line_Item::delete_all_child_items($this);
-                $items_deleted += (int) $this->delete();
-                if ($stop_search_once_found) {
-                    return $items_deleted;
-                }
-            }
-            foreach ($this->children() as $child_line_item) {
-                $items_deleted += $child_line_item->delete_child_line_item($code, $stop_search_once_found);
-            }
-            return $items_deleted;
-        }
-        return $removed;
-    }
-
-
-    /**
-     * If this line item is in the database, is of the type subtotal, and
-     * has no children, why do we have it? It should be deleted so this function
-     * does that
-     *
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function delete_if_childless_subtotal(): bool
-    {
-        if ($this->ID() && $this->type() === EEM_Line_Item::type_sub_total && ! $this->children()) {
-            return $this->delete();
-        }
-        return false;
-    }
-
-
-    /**
-     * Creates a code and returns a string. doesn't assign the code to this model object
-     *
-     * @return string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function generate_code(): string
-    {
-        // each line item in the cart requires a unique identifier
-        return $this->get('OBJ_type') . '-' . $this->get('OBJ_ID');
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function isTax(): bool
-    {
-        return $this->type() === EEM_Line_Item::type_tax || $this->type() === EEM_Line_Item::type_sub_tax;
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function isGlobalTax(): bool
-    {
-        return $this->type() === EEM_Line_Item::type_tax;
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function isSubTax(): bool
-    {
-        return $this->type() === EEM_Line_Item::type_sub_tax;
-    }
-
-
-    /**
-     * returns true if this is a line item with a direct descendent of the type sub-tax
-     *
-     * @return array
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function getSubTaxes(): array
-    {
-        if (! $this->is_line_item()) {
-            return [];
-        }
-        return EEH_Line_Item::get_descendants_of_type($this, EEM_Line_Item::type_sub_tax);
-    }
-
-
-    /**
-     * returns true if this is a line item with a direct descendent of the type sub-tax
-     *
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function hasSubTaxes(): bool
-    {
-        if (! $this->is_line_item()) {
-            return false;
-        }
-        $sub_taxes = $this->getSubTaxes();
-        return ! empty($sub_taxes);
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @deprecated   5.0.0.p
-     */
-    public function is_tax(): bool
-    {
-        return $this->isGlobalTax();
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_tax_sub_total(): bool
-    {
-        return $this->type() === EEM_Line_Item::type_tax_sub_total;
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_line_item(): bool
-    {
-        return $this->type() === EEM_Line_Item::type_line_item;
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_sub_line_item(): bool
-    {
-        return $this->type() === EEM_Line_Item::type_sub_line_item;
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_sub_total(): bool
-    {
-        return $this->type() === EEM_Line_Item::type_sub_total;
-    }
-
-
-    /**
-     * Whether this line item is a cancellation line item
-     *
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_cancellation(): bool
-    {
-        return EEM_Line_Item::type_cancellation === $this->type();
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_total(): bool
-    {
-        return $this->type() === EEM_Line_Item::type_total;
-    }
-
-
-    /**
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function is_cancelled(): bool
-    {
-        return $this->type() === EEM_Line_Item::type_cancellation;
-    }
-
-
-    /**
-     * @return string like '2, 004.00', formatted according to the localized currency
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function unit_price_no_code(): string
-    {
-        return $this->prettyUnitPrice();
-    }
-
-
-    /**
-     * @return string like '2, 004.00', formatted according to the localized currency
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since 5.0.0.p
-     */
-    public function prettyUnitPrice(): string
-    {
-        return $this->get_pretty('LIN_unit_price', 'no_currency_code');
-    }
-
-
-    /**
-     * @return string like '2, 004.00', formatted according to the localized currency
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function total_no_code(): string
-    {
-        return $this->prettyTotal();
-    }
-
-
-    /**
-     * @return string like '2, 004.00', formatted according to the localized currency
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since 5.0.0.p
-     */
-    public function prettyTotal(): string
-    {
-        return $this->get_pretty('LIN_total', 'no_currency_code');
-    }
-
-
-    /**
-     * Gets the final total on this item, taking taxes into account.
-     * Has the side effect of setting the sub-total as it was just calculated.
-     * If this is used on a grand-total line item, also updates the transaction's
-     * TXN_total (provided this line item is allowed to persist, otherwise we don't
-     * want to change a persistable transaction with info from a non-persistent line item)
-     *
-     * @param bool $update_txn_status
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @throws RuntimeException
-     */
-    public function recalculate_total_including_taxes(bool $update_txn_status = false): float
-    {
-        $grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
-        $grand_total_line_item->ensureLineItemsAreSaved();
-        return $this->calculator->recalculateTotalIncludingTaxes($grand_total_line_item, $update_txn_status);
-    }
-
-
-    /**
-     * Recursively goes through all the children and recalculates sub-totals EXCEPT for
-     * tax-sub-totals (they're an odd beast). Updates the 'total' on each line item according to either its
-     * unit price * quantity or the total of all its children EXCEPT when we're only calculating the taxable total and
-     * when this is called on the grand total
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function recalculate_pre_tax_total(): float
-    {
-        $grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
-        $grand_total_line_item->ensureLineItemsAreSaved();
-        [$total] = $this->calculator->recalculateLineItemTotals($grand_total_line_item);
-        return (float) $total;
-    }
-
-
-    /**
-     * Recalculates the total on each individual tax (based on a recalculation of the pre-tax total), sets
-     * the totals on each tax calculated, and returns the final tax total. Re-saves tax line items
-     * and tax sub-total if already in the DB
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function recalculate_taxes_and_tax_total(): float
-    {
-        $grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
-        $grand_total_line_item->ensureLineItemsAreSaved();
-        return $this->calculator->recalculateTaxesAndTaxTotal($grand_total_line_item);
-    }
-
-
-    /**
-     * Gets the total tax on this line item. Assumes taxes have already been calculated using
-     * recalculate_taxes_and_total
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_total_tax(): float
-    {
-        $grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
-        $grand_total_line_item->ensureLineItemsAreSaved();
-        return $this->calculator->recalculateTaxesAndTaxTotal($grand_total_line_item);
-    }
-
-
-    /**
-     * Gets the total for all the items purchased only
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_items_total()
-    {
-        // by default, let's make sure we're consistent with the existing line item
-        if ($this->is_total()) {
-            return $this->pretaxTotal();
-        }
-        $total = 0;
-        foreach ($this->get_items() as $item) {
-            if ($item instanceof EE_Line_Item) {
-                $total += $item->pretaxTotal();
-            }
-        }
-        return $total;
-    }
-
-
-    /**
-     * Gets all the descendants (ie, children or children of children etc.) that
-     * are of the type 'tax'
-     *
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function tax_descendants(): array
-    {
-        return EEH_Line_Item::get_tax_descendants($this);
-    }
-
-
-    /**
-     * Gets all the real items purchased which are children of this item
-     *
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_items(): array
-    {
-        return EEH_Line_Item::get_line_item_descendants($this);
-    }
-
-
-    /**
-     * Returns the amount taxable among this line item's children (or if it has no children,
-     * how much of it is taxable). Does not recalculate totals or subtotals.
-     * If the taxable total is negative, (eg, if none of the tickets were taxable,
-     * but there is a "Taxable" discount), returns 0.
-     *
-     * @return float
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function taxable_total(): float
-    {
-        $this->ensureLineItemsAreSaved();
-        return $this->calculator->taxableAmountForGlobalTaxes($this);
-    }
-
-
-    /**
-     * Gets the transaction for this line item
-     *
-     * @return EE_Transaction|null
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function transaction(): ?EE_Transaction
-    {
-        return $this->get_first_related(EEM_Line_Item::OBJ_TYPE_TRANSACTION);
-    }
-
-
-    /**
-     * Saves this line item to the DB, and recursively saves its descendants.
-     * Because there currently is no proper parent-child relation on the model,
-     * save_this_and_cached() will NOT save the descendants.
-     * Also sets the transaction on this line item and all its descendants before saving
-     *
-     * @param int|null $txn_id if none is provided, assumes $this->TXN_ID()
-     * @return int count of items saved
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function save_this_and_descendants_to_txn(int $txn_id = 0): int
-    {
-        $count = 0;
-        if ($txn_id) {
-            $this->set_TXN_ID($txn_id);
-        }
-        $children = $this->children();
-        $count    += $this->save() ? 1 : 0;
-        foreach ($children as $child_line_item) {
-            if ($child_line_item instanceof EE_Line_Item) {
-                $child_line_item->set_parent_ID($this->ID());
-                $count += $child_line_item->save_this_and_descendants_to_txn($txn_id);
-            }
-        }
-        return $count;
-    }
-
-
-    /**
-     * Saves this line item to the DB, and recursively saves its descendants.
-     *
-     * @return int count of items saved
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function save_this_and_descendants(): int
-    {
-        $count    = 0;
-        $children = $this->children();
-        $count    += $this->save() ? 1 : 0;
-        foreach ($children as $child_line_item) {
-            if ($child_line_item instanceof EE_Line_Item) {
-                $child_line_item->set_parent_ID($this->ID());
-                $count += $child_line_item->save_this_and_descendants();
-            }
-        }
-        return $count;
-    }
-
-
-    /**
-     * returns the cancellation line item if this item was cancelled
-     *
-     * @return EE_Line_Item[]
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws ReflectionException
-     * @throws EE_Error
-     */
-    public function get_cancellations(): array
-    {
-        return EEH_Line_Item::get_descendants_of_type($this, EEM_Line_Item::type_cancellation);
-    }
-
-
-    /**
-     * If this item has an ID, then this saves it again to update the db
-     *
-     * @return bool|int count of items saved or false on error
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function maybe_save()
-    {
-        if ($this->ID()) {
-            return $this->save();
-        }
-        return false;
-    }
-
-
-    /**
-     * clears the cached children and parent from the line item
-     *
-     * @return void
-     */
-    public function clear_related_line_item_cache()
-    {
-        $this->resetChildren();
-        $this->_parent   = null;
-    }
-
-
-    /**
-     * @param bool $raw
-     * @return int|string
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function timestamp(bool $raw = false)
-    {
-        return $raw
-            ? (int) $this->get_raw('LIN_timestamp')
-            : (string) $this->get('LIN_timestamp');
-    }
-
-
-    /**
-     * @return void
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since 5.0.25.p
-     */
-    private function ensureLineItemsAreSaved()
-    {
-        if (! $this->ID()) {
-            $this->save();
-        }
-        $children = $this->children();
-        foreach ($children as $child_line_item) {
-            $child_line_item->ensureLineItemsAreSaved();
-        }
-    }
-
-
-
-
-    /************************* DEPRECATED *************************/
-    /**
-     * @param string $type one of the constants on EEM_Line_Item
-     * @return EE_Line_Item[]
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @deprecated 4.6.0
-     */
-    protected function _get_descendants_of_type(string $type): array
-    {
-        EE_Error::doing_it_wrong(
-            'EE_Line_Item::_get_descendants_of_type()',
-            sprintf(
-                esc_html__('Method replaced with %1$s', 'event_espresso'),
-                'EEH_Line_Item::get_descendants_of_type()'
-            ),
-            '4.6.0'
-        );
-        return EEH_Line_Item::get_descendants_of_type($this, $type);
-    }
-
-
-    /**
-     * @param string $type like one of the EEM_Line_Item::type_*
-     * @return EE_Line_Item
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @deprecated 4.6.0
-     */
-    public function get_nearest_descendant_of_type(string $type): EE_Line_Item
-    {
-        EE_Error::doing_it_wrong(
-            'EE_Line_Item::get_nearest_descendant_of_type()',
-            sprintf(
-                esc_html__('Method replaced with %1$s', 'event_espresso'),
-                'EEH_Line_Item::get_nearest_descendant_of_type()'
-            ),
-            '4.6.0'
-        );
-        return EEH_Line_Item::get_nearest_descendant_of_type($this, $type);
-    }
+	/**
+	 * for children line items (currently not a normal relation)
+	 *
+	 * @var EE_Line_Item[]
+	 */
+	protected array $_children = [];
+
+	/**
+	 * query params used to obtain children line items above
+	 *
+	 * @var array
+	 */
+	private array $children_query_params = [];
+
+	/**
+	 * for the parent line item
+	 *
+	 * @var EE_Line_Item|null
+	 */
+	protected ?EE_Line_Item $_parent = null;
+
+	/**
+	 * @var LineItemCalculator
+	 */
+	protected LineItemCalculator $calculator;
+
+
+	/**
+	 * @param array       $props_n_values incoming values
+	 * @param string|null $timezone       incoming timezone as set by the model.
+	 *                                    If not set the timezone for the website will be used.
+	 * @param array       $date_formats   incoming date_formats in an array where the first value is the
+	 *                                    date_format and the second value is the time format
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function new_instance(
+		array $props_n_values = [],
+		?string $timezone = '',
+		array $date_formats = []
+	): EE_Line_Item {
+		$has_object = parent::_check_for_object(
+			$props_n_values,
+			__CLASS__,
+			$timezone,
+			$date_formats
+		);
+		return $has_object ?: new self($props_n_values, false, $timezone);
+	}
+
+
+	/**
+	 * @param array       $props_n_values incoming values from the database
+	 * @param string|null $timezone       incoming timezone as set by the model.
+	 *                                    If not set the timezone for the website will be used.
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public static function new_instance_from_db(array $props_n_values = [], ?string $timezone = ''): EE_Line_Item
+	{
+		return new self($props_n_values, true, $timezone);
+	}
+
+
+	/**
+	 * Adds some defaults if they're not specified
+	 *
+	 * @param array  $fieldValues
+	 * @param bool   $bydb
+	 * @param string $timezone
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	protected function __construct($fieldValues = [], $bydb = false, $timezone = '')
+	{
+		$this->calculator = LoaderFactory::getShared(LineItemCalculator::class);
+		parent::__construct($fieldValues, $bydb, $timezone);
+		if (! $this->get('LIN_code')) {
+			$this->set_code($this->generate_code());
+		}
+	}
+
+
+	public function __wakeup()
+	{
+		$this->calculator = LoaderFactory::getShared(LineItemCalculator::class);
+		parent::__wakeup();
+	}
+
+
+	/**
+	 * Gets ID
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function ID(): int
+	{
+		return (int) $this->get('LIN_ID');
+	}
+
+
+	/**
+	 * Gets TXN_ID
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function TXN_ID(): int
+	{
+		return (int) $this->get('TXN_ID');
+	}
+
+
+	/**
+	 * Sets TXN_ID
+	 *
+	 * @param int $TXN_ID
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_TXN_ID(int $TXN_ID)
+	{
+		$this->set('TXN_ID', $TXN_ID);
+	}
+
+
+	/**
+	 * Gets name
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function name(): string
+	{
+		$name = (string) $this->get('LIN_name');
+		if (! $name) {
+			$name = ucwords(str_replace('-', ' ', $this->type()));
+		}
+		return $name;
+	}
+
+
+	/**
+	 * Sets name
+	 *
+	 * @param string $name
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_name(string $name)
+	{
+		$this->set('LIN_name', $name);
+	}
+
+
+	/**
+	 * Gets desc
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function desc(): string
+	{
+		return (string) $this->get('LIN_desc');
+	}
+
+
+	/**
+	 * Sets desc
+	 *
+	 * @param string $desc
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_desc(string $desc)
+	{
+		$this->set('LIN_desc', $desc);
+	}
+
+
+	/**
+	 * Gets quantity
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function quantity(): int
+	{
+		return (int) $this->get('LIN_quantity');
+	}
+
+
+	/**
+	 * Sets quantity
+	 *
+	 * @param int $quantity
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_quantity(int $quantity)
+	{
+		$this->set('LIN_quantity', max($quantity, 0));
+	}
+
+
+	/**
+	 * Gets item_id
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function OBJ_ID(): int
+	{
+		return (int) $this->get('OBJ_ID');
+	}
+
+
+	/**
+	 * Sets item_id
+	 *
+	 * @param int $item_id
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_OBJ_ID(int $item_id)
+	{
+		$this->set('OBJ_ID', $item_id);
+	}
+
+
+	/**
+	 * Gets item_type
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function OBJ_type(): string
+	{
+		return (string) $this->get('OBJ_type');
+	}
+
+
+	/**
+	 * Gets item_type
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function OBJ_type_i18n(): string
+	{
+		$obj_type = $this->OBJ_type();
+		switch ($obj_type) {
+			case EEM_Line_Item::OBJ_TYPE_EVENT:
+				$obj_type = esc_html__('Event', 'event_espresso');
+				break;
+			case EEM_Line_Item::OBJ_TYPE_PRICE:
+				$obj_type = esc_html__('Price', 'event_espresso');
+				break;
+			case EEM_Line_Item::OBJ_TYPE_PROMOTION:
+				$obj_type = esc_html__('Promotion', 'event_espresso');
+				break;
+			case EEM_Line_Item::OBJ_TYPE_TICKET:
+				$obj_type = esc_html__('Ticket', 'event_espresso');
+				break;
+			case EEM_Line_Item::OBJ_TYPE_TRANSACTION:
+				$obj_type = esc_html__('Transaction', 'event_espresso');
+				break;
+		}
+		return (string) apply_filters('FHEE__EE_Line_Item__OBJ_type_i18n', $obj_type, $this);
+	}
+
+
+	/**
+	 * Sets item_type
+	 *
+	 * @param string $OBJ_type
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_OBJ_type(string $OBJ_type)
+	{
+		$this->set('OBJ_type', $OBJ_type);
+	}
+
+
+	/**
+	 * Gets unit_price
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function unit_price(): float
+	{
+		return (float) $this->get('LIN_unit_price');
+	}
+
+
+	/**
+	 * Sets unit_price
+	 *
+	 * @param int|float $unit_price
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_unit_price($unit_price)
+	{
+		$this->set('LIN_unit_price', (float) $unit_price);
+	}
+
+
+	/**
+	 * Checks if this item is a percentage modifier or not
+	 *
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_percent(): bool
+	{
+		if ($this->is_tax_sub_total()) {
+			// tax subtotals HAVE a percent on them, that percentage only applies
+			// to taxable items, so it's an exception. Treat it like a flat line item
+			return false;
+		}
+		$unit_price = abs($this->get('LIN_unit_price'));
+		$percent    = abs($this->get('LIN_percent'));
+		if ($unit_price < .001 && $percent) {
+			return true;
+		}
+		if ($unit_price >= .001 && ! $percent) {
+			return false;
+		}
+		if ($unit_price >= .001 && $percent) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'A Line Item can not have a unit price of (%s) AND a percent (%s)!',
+						'event_espresso'
+					),
+					$unit_price,
+					$percent
+				)
+			);
+		}
+		// if they're both 0, assume it's not a percent item
+		return false;
+	}
+
+
+	/**
+	 * Gets percent (between 100-.001)
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function percent(): float
+	{
+		return (float) $this->get('LIN_percent');
+	}
+
+
+	/**
+	 * @return string
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since 5.0.0.p
+	 */
+	public function prettyPercent(): string
+	{
+		return (string) $this->get_pretty('LIN_percent');
+	}
+
+
+	/**
+	 * Sets percent (between 100-0.01)
+	 *
+	 * @param int|float $percent
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_percent($percent)
+	{
+		$this->set('LIN_percent', (float) $percent);
+	}
+
+
+	/**
+	 * Gets total
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function pretaxTotal(): float
+	{
+		return (float) $this->get('LIN_pretax');
+	}
+
+
+	/**
+	 * Sets total
+	 *
+	 * @param int|float $pretax_total
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function setPretaxTotal($pretax_total)
+	{
+		$this->set('LIN_pretax', (float) $pretax_total);
+	}
+
+
+	/**
+	 * @return float
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since  5.0.0.p
+	 */
+	public function totalWithTax(): float
+	{
+		return (float) $this->get('LIN_total');
+	}
+
+
+	/**
+	 * Sets total
+	 *
+	 * @param int|float $total
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since  5.0.0.p
+	 */
+	public function setTotalWithTax($total)
+	{
+		$this->set('LIN_total', (float) $total);
+	}
+
+
+	/**
+	 * Gets total
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @deprecatd 5.0.0.p
+	 */
+	public function total(): float
+	{
+		return $this->totalWithTax();
+	}
+
+
+	/**
+	 * Sets total
+	 *
+	 * @param int|float $total
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @deprecatd 5.0.0.p
+	 */
+	public function set_total($total)
+	{
+		$this->setTotalWithTax((float) $total);
+	}
+
+
+	/**
+	 * Gets order
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function order(): int
+	{
+		return (int) $this->get('LIN_order');
+	}
+
+
+	/**
+	 * Sets order
+	 *
+	 * @param int $order
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_order(int $order)
+	{
+		$this->set('LIN_order', $order);
+	}
+
+
+	/**
+	 * Gets parent
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function parent_ID(): int
+	{
+		return (int) $this->get('LIN_parent');
+	}
+
+
+	/**
+	 * Sets parent
+	 *
+	 * @param int $parent
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_parent_ID(int $parent)
+	{
+		$this->set('LIN_parent', $parent);
+	}
+
+
+	/**
+	 * Gets type
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function type(): string
+	{
+		return (string) $this->get('LIN_type');
+	}
+
+
+	/**
+	 * Sets type
+	 *
+	 * @param string $type
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_type(string $type)
+	{
+		$this->set('LIN_type', $type);
+	}
+
+
+	/**
+	 * Gets the line item of which this item is a composite. Eg, if this is a subtotal, the parent might be a total\
+	 * If this line item is saved to the DB, fetches the parent from the DB. However, if this line item isn't in the DB
+	 * it uses its cached reference to its parent line item (which would have been set by `EE_Line_Item::set_parent()`
+	 * or indirectly by `EE_Line_item::add_child_line_item()`)
+	 *
+	 * @return EE_Line_Item|null
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function parent(): ?EE_Line_Item
+	{
+		if (! $this->_parent instanceof EE_Line_Item) {
+			$this->_parent = $this->ID()
+				? $this->get_model()->get_one_by_ID($this->parent_ID())
+				: $this->_parent;
+		}
+		return $this->_parent;
+	}
+
+
+	/**
+	 * Gets ALL the children of this line item (ie, all the parts that contribute towards this total).
+	 *
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function children(array $query_params = []): array
+	{
+		// check if the query params have changed since the last time we ran this query
+		$new_params = ! empty(EEH_Array::array_diff_recursive($query_params, $this->children_query_params));
+		if (($new_params || empty($this->_children)) && $this->ID()) {
+			$this->children_query_params = $query_params;
+			// ensure where params are an array
+			$query_params[0] = isset($query_params[0]) && is_array($query_params[0]) ? $query_params[0] : [];
+			// add defaults for line item parent and orderby
+			$query_params[0] += ['LIN_parent' => $this->ID()];
+			$query_params    += ['order_by' => ['LIN_order' => 'ASC']];
+			$children = $this->get_model()->get_all($query_params);
+			foreach ($children as $child) {
+				if ($child instanceof EE_Line_Item) {
+					$this->addLineItemToChildren($child);
+				}
+			}
+		}
+		return $this->_children;
+	}
+
+
+	private function addLineItemToChildren($child_line_item)
+	{
+		$this->_children[ $child_line_item->code() ] = $child_line_item;
+	}
+
+
+	private function getChildLineItemFromCache(string $code): ?EE_Line_Item
+	{
+		return $this->_children[ $code ] ?? null;
+	}
+
+
+	private function removeChildLineItemFromCache(string $code): int
+	{
+		if (isset($this->_children[ $code ])) {
+			unset($this->_children[ $code ]);
+			return 1;
+		}
+		return 0;
+	}
+
+
+	private function resetChildren()
+	{
+		$this->_children = [];
+	}
+
+
+	/**
+	 * Gets code
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function code(): string
+	{
+		return (string) $this->get('LIN_code');
+	}
+
+
+	/**
+	 * Sets code
+	 *
+	 * @param string $code
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_code(string $code)
+	{
+		$this->set('LIN_code', $code);
+	}
+
+
+	/**
+	 * Gets is_taxable
+	 *
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_taxable(): bool
+	{
+		return (bool) $this->get('LIN_is_taxable');
+	}
+
+
+	/**
+	 * Sets is_taxable
+	 *
+	 * @param bool $is_taxable
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_is_taxable(bool $is_taxable)
+	{
+		$this->set('LIN_is_taxable', $is_taxable);
+	}
+
+
+	/**
+	 * @param int $timestamp
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since 5.0.0.p
+	 */
+	public function setTimestamp(int $timestamp)
+	{
+		$this->set('LIN_timestamp', $timestamp);
+	}
+
+
+	/**
+	 * Gets the object that this model-joins-to.
+	 * returns one of the model objects that the field OBJ_ID can point to... see the 'OBJ_ID' field on
+	 * EEM_Promotion_Object
+	 *        Eg, if this line item join model object is for a ticket, this will return the EE_Ticket object
+	 *
+	 * @return EE_Base_Class|null
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_object(): ?EE_Base_Class
+	{
+		$model_name_of_related_obj = $this->OBJ_type();
+		return $this->get_model()->has_relation($model_name_of_related_obj)
+			? $this->get_first_related($model_name_of_related_obj)
+			: null;
+	}
+
+
+	/**
+	 * Like EE_Line_Item::get_object(), but can only ever actually return an EE_Ticket.
+	 * (IE, if this line item is for a price or something else, will return NULL)
+	 *
+	 * @param array $query_params deprecated 5.0.12.p
+	 * @return EE_Ticket|null
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function ticket(array $query_params = []): ?EE_Ticket
+	{
+		// we're going to assume that when this method is called
+		// we always want to receive the attached ticket EVEN if that ticket is archived.
+		if(! $this->OBJ_ID() || $this->OBJ_type() !== EEM_Line_Item::OBJ_TYPE_TICKET) {
+			return null;
+		}
+		if(empty($query_args)) {
+			return EEM_Ticket::instance()->get_one_by_ID($this->OBJ_ID());
+		}
+		// legacy usage
+		$query_params += ['default_where_conditions' => 'none'];
+		return $this->get_first_related(EEM_Line_Item::OBJ_TYPE_TICKET, $query_params);
+	}
+
+
+	/**
+	 * Gets the EE_Datetime that's related to the ticket, IF this is for a ticket
+	 *
+	 * @return EE_Datetime|null
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_ticket_datetime(): ?EE_Datetime
+	{
+		if ($this->OBJ_type() === EEM_Line_Item::OBJ_TYPE_TICKET) {
+			$ticket = $this->ticket();
+			if ($ticket instanceof EE_Ticket) {
+				$datetime = $ticket->first_datetime();
+				if ($datetime instanceof EE_Datetime) {
+					return $datetime;
+				}
+			}
+		}
+		return null;
+	}
+
+
+	/**
+	 * Gets the event's name that's related to the ticket, if this is for
+	 * a ticket
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function ticket_event_name(): string
+	{
+		$event_name = esc_html__('Unknown', 'event_espresso');
+		$event      = $this->ticket_event();
+		if ($event instanceof EE_Event) {
+			$event_name = $event->name();
+		}
+		return $event_name;
+	}
+
+
+	/**
+	 * Gets the event that's related to the ticket, if this line item represents a ticket.
+	 *
+	 * @return EE_Event|null
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function ticket_event(): ?EE_Event
+	{
+		$event  = null;
+		$ticket = $this->ticket();
+		if ($ticket instanceof EE_Ticket) {
+			$datetime = $ticket->first_datetime();
+			if ($datetime instanceof EE_Datetime) {
+				$event = $datetime->event();
+			}
+		}
+		return $event;
+	}
+
+
+	/**
+	 * Gets the first datetime for this lien item, assuming it's for a ticket
+	 *
+	 * @param string $date_format
+	 * @param string $time_format
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function ticket_datetime_start(string $date_format = '', string $time_format = ''): string
+	{
+		$first_datetime_string = esc_html__('Unknown', 'event_espresso');
+		$datetime              = $this->get_ticket_datetime();
+		if ($datetime) {
+			$first_datetime_string = $datetime->start_date_and_time($date_format, $time_format);
+		}
+		return $first_datetime_string;
+	}
+
+
+	/**
+	 * Adds the line item as a child to this line item. If there is another child line
+	 * item with the same LIN_code, it is overwritten by this new one
+	 *
+	 * @param EE_Line_Item $line_item
+	 * @param bool         $set_order
+	 * @return bool success
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function add_child_line_item(EE_Line_Item $line_item, bool $set_order = true): bool
+	{
+		// should we calculate the LIN_order for this line item ?
+		if ($set_order || $line_item->order() === null) {
+			$line_item->set_order(count($this->children()));
+		}
+		if ($this->ID()) {
+			// check for any duplicate line items (with the same code), if so, this replaces it
+			$line_item_with_same_code = $this->get_child_line_item($line_item->code());
+			if ($line_item_with_same_code instanceof EE_Line_Item && $line_item_with_same_code !== $line_item) {
+				$this->delete_child_line_item($line_item_with_same_code->code());
+			}
+			$line_item->set_parent_ID($this->ID());
+			if ($this->TXN_ID()) {
+				$line_item->set_TXN_ID($this->TXN_ID());
+			}
+			$this->addLineItemToChildren($line_item);
+			return (bool) $line_item->save();
+		}
+		$this->addLineItemToChildren($line_item);
+		if ($line_item->parent() !== $this) {
+			$line_item->set_parent($this);
+		}
+		return true;
+	}
+
+
+	/**
+	 * Similar to EE_Base_Class::_add_relation_to, except this isn't a normal relation.
+	 * If this line item is saved to the DB, this is just a wrapper for set_parent_ID() and save()
+	 * However, if this line item is NOT saved to the DB, this just caches the parent on
+	 * the EE_Line_Item::_parent property.
+	 *
+	 * @param EE_Line_Item $line_item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function set_parent(EE_Line_Item $line_item)
+	{
+		if ($this->ID()) {
+			if (! $line_item->ID()) {
+				$line_item->save();
+			}
+			$this->set_parent_ID($line_item->ID());
+			$this->save();
+		} else {
+			$this->_parent = $line_item;
+			$this->set_parent_ID($line_item->ID());
+		}
+	}
+
+
+	/**
+	 * Gets the child line item as specified by its code. Because this returns an object (by reference)
+	 * you can modify this child line item and the parent (this object) can know about them
+	 * because it also has a reference to that line item
+	 *
+	 * @param string $code
+	 * @return EE_Base_Class|EE_Line_Item|EE_Soft_Delete_Base_Class|NULL
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_child_line_item(string $code)
+	{
+		$child = $this->getChildLineItemFromCache($code);
+		if ($child instanceof EE_Line_Item) {
+			return $child;
+		}
+		if ($this->ID()) {
+			return $this->get_model()->get_one(
+				[['LIN_parent' => $this->ID(), 'LIN_code' => $code]]
+			);
+		}
+		return null;
+	}
+
+
+	/**
+	 * Returns how many items are deleted (or, if this item has not been saved ot the DB yet, just how many it HAD
+	 * cached on it)
+	 *
+	 * @return int
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function delete_children_line_items(): int
+	{
+		$count = count($this->_children);
+		$this->resetChildren();
+		return $this->ID() ? (int) $this->get_model()->delete([['LIN_parent' => $this->ID()]]) : $count;
+	}
+
+
+	/**
+	 * If this line item has been saved to the DB, deletes its child with LIN_code == $code. If this line
+	 * HAS NOT been saved to the DB, removes the child line item with index $code.
+	 * Also searches through the child's children for a matching line item. However, once a line item has been found
+	 * and deleted, stops searching (so if there are line items with duplicate codes, only the first one found will be
+	 * deleted)
+	 *
+	 * @param string $code
+	 * @param bool   $stop_search_once_found
+	 * @return int count of items deleted (or simply removed from the line item's cache, if not has not been saved to
+	 *             the DB yet)
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function delete_child_line_item(string $code, bool $stop_search_once_found = true): int
+	{
+		$removed = $this->removeChildLineItemFromCache($code);
+		if ($this->ID()) {
+			$items_deleted = 0;
+			if ($this->code() === $code) {
+				$items_deleted += EEH_Line_Item::delete_all_child_items($this);
+				$items_deleted += (int) $this->delete();
+				if ($stop_search_once_found) {
+					return $items_deleted;
+				}
+			}
+			foreach ($this->children() as $child_line_item) {
+				$items_deleted += $child_line_item->delete_child_line_item($code, $stop_search_once_found);
+			}
+			return $items_deleted;
+		}
+		return $removed;
+	}
+
+
+	/**
+	 * If this line item is in the database, is of the type subtotal, and
+	 * has no children, why do we have it? It should be deleted so this function
+	 * does that
+	 *
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function delete_if_childless_subtotal(): bool
+	{
+		if ($this->ID() && $this->type() === EEM_Line_Item::type_sub_total && ! $this->children()) {
+			return $this->delete();
+		}
+		return false;
+	}
+
+
+	/**
+	 * Creates a code and returns a string. doesn't assign the code to this model object
+	 *
+	 * @return string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function generate_code(): string
+	{
+		// each line item in the cart requires a unique identifier
+		return $this->get('OBJ_type') . '-' . $this->get('OBJ_ID');
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function isTax(): bool
+	{
+		return $this->type() === EEM_Line_Item::type_tax || $this->type() === EEM_Line_Item::type_sub_tax;
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function isGlobalTax(): bool
+	{
+		return $this->type() === EEM_Line_Item::type_tax;
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function isSubTax(): bool
+	{
+		return $this->type() === EEM_Line_Item::type_sub_tax;
+	}
+
+
+	/**
+	 * returns true if this is a line item with a direct descendent of the type sub-tax
+	 *
+	 * @return array
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function getSubTaxes(): array
+	{
+		if (! $this->is_line_item()) {
+			return [];
+		}
+		return EEH_Line_Item::get_descendants_of_type($this, EEM_Line_Item::type_sub_tax);
+	}
+
+
+	/**
+	 * returns true if this is a line item with a direct descendent of the type sub-tax
+	 *
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function hasSubTaxes(): bool
+	{
+		if (! $this->is_line_item()) {
+			return false;
+		}
+		$sub_taxes = $this->getSubTaxes();
+		return ! empty($sub_taxes);
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @deprecated   5.0.0.p
+	 */
+	public function is_tax(): bool
+	{
+		return $this->isGlobalTax();
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_tax_sub_total(): bool
+	{
+		return $this->type() === EEM_Line_Item::type_tax_sub_total;
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_line_item(): bool
+	{
+		return $this->type() === EEM_Line_Item::type_line_item;
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_sub_line_item(): bool
+	{
+		return $this->type() === EEM_Line_Item::type_sub_line_item;
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_sub_total(): bool
+	{
+		return $this->type() === EEM_Line_Item::type_sub_total;
+	}
+
+
+	/**
+	 * Whether this line item is a cancellation line item
+	 *
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_cancellation(): bool
+	{
+		return EEM_Line_Item::type_cancellation === $this->type();
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_total(): bool
+	{
+		return $this->type() === EEM_Line_Item::type_total;
+	}
+
+
+	/**
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function is_cancelled(): bool
+	{
+		return $this->type() === EEM_Line_Item::type_cancellation;
+	}
+
+
+	/**
+	 * @return string like '2, 004.00', formatted according to the localized currency
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function unit_price_no_code(): string
+	{
+		return $this->prettyUnitPrice();
+	}
+
+
+	/**
+	 * @return string like '2, 004.00', formatted according to the localized currency
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since 5.0.0.p
+	 */
+	public function prettyUnitPrice(): string
+	{
+		return $this->get_pretty('LIN_unit_price', 'no_currency_code');
+	}
+
+
+	/**
+	 * @return string like '2, 004.00', formatted according to the localized currency
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function total_no_code(): string
+	{
+		return $this->prettyTotal();
+	}
+
+
+	/**
+	 * @return string like '2, 004.00', formatted according to the localized currency
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since 5.0.0.p
+	 */
+	public function prettyTotal(): string
+	{
+		return $this->get_pretty('LIN_total', 'no_currency_code');
+	}
+
+
+	/**
+	 * Gets the final total on this item, taking taxes into account.
+	 * Has the side effect of setting the sub-total as it was just calculated.
+	 * If this is used on a grand-total line item, also updates the transaction's
+	 * TXN_total (provided this line item is allowed to persist, otherwise we don't
+	 * want to change a persistable transaction with info from a non-persistent line item)
+	 *
+	 * @param bool $update_txn_status
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @throws RuntimeException
+	 */
+	public function recalculate_total_including_taxes(bool $update_txn_status = false): float
+	{
+		$grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
+		$grand_total_line_item->ensureLineItemsAreSaved();
+		return $this->calculator->recalculateTotalIncludingTaxes($grand_total_line_item, $update_txn_status);
+	}
+
+
+	/**
+	 * Recursively goes through all the children and recalculates sub-totals EXCEPT for
+	 * tax-sub-totals (they're an odd beast). Updates the 'total' on each line item according to either its
+	 * unit price * quantity or the total of all its children EXCEPT when we're only calculating the taxable total and
+	 * when this is called on the grand total
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function recalculate_pre_tax_total(): float
+	{
+		$grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
+		$grand_total_line_item->ensureLineItemsAreSaved();
+		[$total] = $this->calculator->recalculateLineItemTotals($grand_total_line_item);
+		return (float) $total;
+	}
+
+
+	/**
+	 * Recalculates the total on each individual tax (based on a recalculation of the pre-tax total), sets
+	 * the totals on each tax calculated, and returns the final tax total. Re-saves tax line items
+	 * and tax sub-total if already in the DB
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function recalculate_taxes_and_tax_total(): float
+	{
+		$grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
+		$grand_total_line_item->ensureLineItemsAreSaved();
+		return $this->calculator->recalculateTaxesAndTaxTotal($grand_total_line_item);
+	}
+
+
+	/**
+	 * Gets the total tax on this line item. Assumes taxes have already been calculated using
+	 * recalculate_taxes_and_total
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_total_tax(): float
+	{
+		$grand_total_line_item = EEH_Line_Item::find_transaction_grand_total_for_line_item($this);
+		$grand_total_line_item->ensureLineItemsAreSaved();
+		return $this->calculator->recalculateTaxesAndTaxTotal($grand_total_line_item);
+	}
+
+
+	/**
+	 * Gets the total for all the items purchased only
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_items_total()
+	{
+		// by default, let's make sure we're consistent with the existing line item
+		if ($this->is_total()) {
+			return $this->pretaxTotal();
+		}
+		$total = 0;
+		foreach ($this->get_items() as $item) {
+			if ($item instanceof EE_Line_Item) {
+				$total += $item->pretaxTotal();
+			}
+		}
+		return $total;
+	}
+
+
+	/**
+	 * Gets all the descendants (ie, children or children of children etc.) that
+	 * are of the type 'tax'
+	 *
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function tax_descendants(): array
+	{
+		return EEH_Line_Item::get_tax_descendants($this);
+	}
+
+
+	/**
+	 * Gets all the real items purchased which are children of this item
+	 *
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_items(): array
+	{
+		return EEH_Line_Item::get_line_item_descendants($this);
+	}
+
+
+	/**
+	 * Returns the amount taxable among this line item's children (or if it has no children,
+	 * how much of it is taxable). Does not recalculate totals or subtotals.
+	 * If the taxable total is negative, (eg, if none of the tickets were taxable,
+	 * but there is a "Taxable" discount), returns 0.
+	 *
+	 * @return float
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function taxable_total(): float
+	{
+		$this->ensureLineItemsAreSaved();
+		return $this->calculator->taxableAmountForGlobalTaxes($this);
+	}
+
+
+	/**
+	 * Gets the transaction for this line item
+	 *
+	 * @return EE_Transaction|null
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function transaction(): ?EE_Transaction
+	{
+		return $this->get_first_related(EEM_Line_Item::OBJ_TYPE_TRANSACTION);
+	}
+
+
+	/**
+	 * Saves this line item to the DB, and recursively saves its descendants.
+	 * Because there currently is no proper parent-child relation on the model,
+	 * save_this_and_cached() will NOT save the descendants.
+	 * Also sets the transaction on this line item and all its descendants before saving
+	 *
+	 * @param int|null $txn_id if none is provided, assumes $this->TXN_ID()
+	 * @return int count of items saved
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function save_this_and_descendants_to_txn(int $txn_id = 0): int
+	{
+		$count = 0;
+		if ($txn_id) {
+			$this->set_TXN_ID($txn_id);
+		}
+		$children = $this->children();
+		$count    += $this->save() ? 1 : 0;
+		foreach ($children as $child_line_item) {
+			if ($child_line_item instanceof EE_Line_Item) {
+				$child_line_item->set_parent_ID($this->ID());
+				$count += $child_line_item->save_this_and_descendants_to_txn($txn_id);
+			}
+		}
+		return $count;
+	}
+
+
+	/**
+	 * Saves this line item to the DB, and recursively saves its descendants.
+	 *
+	 * @return int count of items saved
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function save_this_and_descendants(): int
+	{
+		$count    = 0;
+		$children = $this->children();
+		$count    += $this->save() ? 1 : 0;
+		foreach ($children as $child_line_item) {
+			if ($child_line_item instanceof EE_Line_Item) {
+				$child_line_item->set_parent_ID($this->ID());
+				$count += $child_line_item->save_this_and_descendants();
+			}
+		}
+		return $count;
+	}
+
+
+	/**
+	 * returns the cancellation line item if this item was cancelled
+	 *
+	 * @return EE_Line_Item[]
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws ReflectionException
+	 * @throws EE_Error
+	 */
+	public function get_cancellations(): array
+	{
+		return EEH_Line_Item::get_descendants_of_type($this, EEM_Line_Item::type_cancellation);
+	}
+
+
+	/**
+	 * If this item has an ID, then this saves it again to update the db
+	 *
+	 * @return bool|int count of items saved or false on error
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function maybe_save()
+	{
+		if ($this->ID()) {
+			return $this->save();
+		}
+		return false;
+	}
+
+
+	/**
+	 * clears the cached children and parent from the line item
+	 *
+	 * @return void
+	 */
+	public function clear_related_line_item_cache()
+	{
+		$this->resetChildren();
+		$this->_parent   = null;
+	}
+
+
+	/**
+	 * @param bool $raw
+	 * @return int|string
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function timestamp(bool $raw = false)
+	{
+		return $raw
+			? (int) $this->get_raw('LIN_timestamp')
+			: (string) $this->get('LIN_timestamp');
+	}
+
+
+	/**
+	 * @return void
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since 5.0.25.p
+	 */
+	private function ensureLineItemsAreSaved()
+	{
+		if (! $this->ID()) {
+			$this->save();
+		}
+		$children = $this->children();
+		foreach ($children as $child_line_item) {
+			$child_line_item->ensureLineItemsAreSaved();
+		}
+	}
+
+
+
+
+	/************************* DEPRECATED *************************/
+	/**
+	 * @param string $type one of the constants on EEM_Line_Item
+	 * @return EE_Line_Item[]
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @deprecated 4.6.0
+	 */
+	protected function _get_descendants_of_type(string $type): array
+	{
+		EE_Error::doing_it_wrong(
+			'EE_Line_Item::_get_descendants_of_type()',
+			sprintf(
+				esc_html__('Method replaced with %1$s', 'event_espresso'),
+				'EEH_Line_Item::get_descendants_of_type()'
+			),
+			'4.6.0'
+		);
+		return EEH_Line_Item::get_descendants_of_type($this, $type);
+	}
+
+
+	/**
+	 * @param string $type like one of the EEM_Line_Item::type_*
+	 * @return EE_Line_Item
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @deprecated 4.6.0
+	 */
+	public function get_nearest_descendant_of_type(string $type): EE_Line_Item
+	{
+		EE_Error::doing_it_wrong(
+			'EE_Line_Item::get_nearest_descendant_of_type()',
+			sprintf(
+				esc_html__('Method replaced with %1$s', 'event_espresso'),
+				'EEH_Line_Item::get_nearest_descendant_of_type()'
+			),
+			'4.6.0'
+		);
+		return EEH_Line_Item::get_nearest_descendant_of_type($this, $type);
+	}
 }

Spacing +17 added lines, -17 removed lines

@@ -104,7 +104,7 @@ 
     {
         $this->calculator = LoaderFactory::getShared(LineItemCalculator::class);
         parent::__construct($fieldValues, $bydb, $timezone);
-        if (! $this->get('LIN_code')) {
+        if ( ! $this->get('LIN_code')) {
             $this->set_code($this->generate_code());
         }
     }
@@ -178,7 +178,7 @@ 
     public function name(): string
     {
         $name = (string) $this->get('LIN_name');
-        if (! $name) {
+        if ( ! $name) {
             $name = ucwords(str_replace('-', ' ', $this->type()));
         }
         return $name;
@@ -678,7 +678,7 @@ 
      */
     public function parent(): ?EE_Line_Item
     {
-        if (! $this->_parent instanceof EE_Line_Item) {
+        if ( ! $this->_parent instanceof EE_Line_Item) {
             $this->_parent = $this->ID()
                 ? $this->get_model()->get_one_by_ID($this->parent_ID())
                 : $this->_parent;
@@ -721,20 +721,20 @@ 
 
     private function addLineItemToChildren($child_line_item)
     {
-        $this->_children[ $child_line_item->code() ] = $child_line_item;
+        $this->_children[$child_line_item->code()] = $child_line_item;
     }
 
 
     private function getChildLineItemFromCache(string $code): ?EE_Line_Item
     {
-        return $this->_children[ $code ] ?? null;
+        return $this->_children[$code] ?? null;
     }
 
 
     private function removeChildLineItemFromCache(string $code): int
     {
-        if (isset($this->_children[ $code ])) {
-            unset($this->_children[ $code ]);
+        if (isset($this->_children[$code])) {
+            unset($this->_children[$code]);
             return 1;
         }
         return 0;
@@ -858,10 +858,10 @@ 
     {
         // we're going to assume that when this method is called
         // we always want to receive the attached ticket EVEN if that ticket is archived.
-        if(! $this->OBJ_ID() || $this->OBJ_type() !== EEM_Line_Item::OBJ_TYPE_TICKET) {
+        if ( ! $this->OBJ_ID() || $this->OBJ_type() !== EEM_Line_Item::OBJ_TYPE_TICKET) {
             return null;
         }
-        if(empty($query_args)) {
+        if (empty($query_args)) {
             return EEM_Ticket::instance()->get_one_by_ID($this->OBJ_ID());
         }
         // legacy usage
@@ -1020,7 +1020,7 @@ 
     public function set_parent(EE_Line_Item $line_item)
     {
         if ($this->ID()) {
-            if (! $line_item->ID()) {
+            if ( ! $line_item->ID()) {
                 $line_item->save();
             }
             $this->set_parent_ID($line_item->ID());
@@ -1151,7 +1151,7 @@ 
     public function generate_code(): string
     {
         // each line item in the cart requires a unique identifier
-        return $this->get('OBJ_type') . '-' . $this->get('OBJ_ID');
+        return $this->get('OBJ_type').'-'.$this->get('OBJ_ID');
     }
 
 
@@ -1209,7 +1209,7 @@ 
      */
     public function getSubTaxes(): array
     {
-        if (! $this->is_line_item()) {
+        if ( ! $this->is_line_item()) {
             return [];
         }
         return EEH_Line_Item::get_descendants_of_type($this, EEM_Line_Item::type_sub_tax);
@@ -1228,7 +1228,7 @@ 
      */
     public function hasSubTaxes(): bool
     {
-        if (! $this->is_line_item()) {
+        if ( ! $this->is_line_item()) {
             return false;
         }
         $sub_taxes = $this->getSubTaxes();
@@ -1589,7 +1589,7 @@ 
             $this->set_TXN_ID($txn_id);
         }
         $children = $this->children();
-        $count    += $this->save() ? 1 : 0;
+        $count += $this->save() ? 1 : 0;
         foreach ($children as $child_line_item) {
             if ($child_line_item instanceof EE_Line_Item) {
                 $child_line_item->set_parent_ID($this->ID());
@@ -1614,7 +1614,7 @@ 
     {
         $count    = 0;
         $children = $this->children();
-        $count    += $this->save() ? 1 : 0;
+        $count += $this->save() ? 1 : 0;
         foreach ($children as $child_line_item) {
             if ($child_line_item instanceof EE_Line_Item) {
                 $child_line_item->set_parent_ID($this->ID());
@@ -1668,7 +1668,7 @@ 
     public function clear_related_line_item_cache()
     {
         $this->resetChildren();
-        $this->_parent   = null;
+        $this->_parent = null;
     }
 
 
@@ -1697,7 +1697,7 @@ 
      */
     private function ensureLineItemsAreSaved()
     {
-        if (! $this->ID()) {
+        if ( ! $this->ID()) {
             $this->save();
         }
         $children = $this->children();

core/db_classes/EE_Base_Class.class.php

Indentation +3359 added lines, -3359 removed lines

@@ -16,3374 +16,3374 @@
 abstract class EE_Base_Class
 {
 
-    /**
-     * @var EEM_Base|null
-     */
-    protected $_model = null;
-
-    /**
-     * This is an array of the original properties and values provided during construction
-     * of this model object. (keys are model field names, values are their values).
-     * This list is important to remember so that when we are merging data from the db, we know
-     * which values to override and which to not override.
-     */
-    protected ?array $_props_n_values_provided_in_constructor = null;
-
-    /**
-     * Timezone
-     * This gets set by the "set_timezone()" method so that we know what timezone incoming strings|timestamps are in.
-     * This can also be used before a get to set what timezone you want strings coming out of the object to be in.  NOT
-     * all EE_Base_Class child classes use this property but any that use a EE_Datetime_Field data type will have
-     * access to it.
-     */
-    protected string $_timezone = '';
-
-    /**
-     * date format
-     * pattern or format for displaying dates
-     */
-    protected string $_dt_frmt = '';
-
-    /**
-     * time format
-     * pattern or format for displaying time
-     */
-    protected string $_tm_frmt = '';
-
-    /**
-     * This property is for holding a cached array of object properties indexed by property name as the key.
-     * The purpose of this is for setting a cache on properties that may have calculated values after a
-     * prepare_for_get.  That way the cache can be checked first and the calculated property returned instead of having
-     * to recalculate. Used by _set_cached_property() and _get_cached_property() methods.
-     */
-    protected array $_cached_properties = [];
-
-    /**
-     * An array containing keys of the related model, and values are either an array of related mode objects or a
-     * single
-     * related model object. see the model's _model_relations. The keys should match those specified. And if the
-     * relation is of type EE_Belongs_To (or one of its children), then there should only be ONE related model object,
-     * all others have an array)
-     */
-    protected array $_model_relations = [];
-
-    /**
-     * Array where keys are field names (see the model's _fields property) and values are their values. To see what
-     * their types should be, look at what that field object returns on its prepare_for_get and prepare_for_set methods)
-     */
-    protected array $_fields = [];
-
-    /**
-     * indicating whether or not this model object is intended to ever be saved
-     * For example, we might create model objects intended to only be used for the duration
-     * of this request and to be thrown away, and if they were accidentally saved
-     * it would be a bug.
-     */
-    protected bool $_allow_persist = true;
-
-    /**
-     * indicating whether or not this model object's properties have changed since construction
-     */
-    protected bool $_has_changes = false;
-
-    /**
-     * This is a cache of results from custom selections done on a query that constructs this entity. The only purpose
-     * for these values is for retrieval of the results, they are not further queryable and they are not persisted to
-     * the db.  They also do not automatically update if there are any changes to the data that produced their results.
-     * The format is a simple array of field_alias => field_value.  So for instance if a custom select was something
-     * like,  "Select COUNT(Registration.REG_ID) as Registration_Count ...", then the resulting value will be in this
-     * array as:
-     * array(
-     *  'Registration_Count' => 24
-     * );
-     * Note: if the custom select configuration for the query included a data type, the value will be in the data type
-     * provided for the query (@see EventEspresso\core\domain\values\model\CustomSelects::__construct phpdocs for more
-     * info)
-     */
-    protected array $custom_selection_results = [];
-
-
-    /**
-     * basic constructor for Event Espresso classes, performs any necessary initialization, and verifies it's children
-     * play nice
-     *
-     * @param array   $fieldValues                             where each key is a field (ie, array key in the 2nd
-     *                                                         layer of the model's _fields array, (eg, EVT_ID,
-     *                                                         TXN_amount, QST_name, etc) and values are their values
-     * @param boolean $bydb                                    a flag for setting if the class is instantiated by the
-     *                                                         corresponding db model or not.
-     * @param string  $timezone                                indicate what timezone you want any datetime fields to
-     *                                                         be in when instantiating a EE_Base_Class object.
-     * @param array   $date_formats                            An array of date formats to set on construct where first
-     *                                                         value is the date_format and second value is the time
-     *                                                         format.
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    protected function __construct($fieldValues = [], $bydb = false, $timezone = '', $date_formats = [])
-    {
-        $className = get_class($this);
-        do_action("AHEE__{$className}__construct", $this, $fieldValues);
-        $model        = $this->get_model();
-        $model_fields = $model->field_settings();
-        // ensure $fieldValues is an array
-        $fieldValues = is_array($fieldValues) ? $fieldValues : [$fieldValues];
-        // verify client code has not passed any invalid field names
-        foreach ($fieldValues as $field_name => $field_value) {
-            if (! isset($model_fields[ $field_name ])) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            'Invalid field (%s) passed to constructor of %s. Allowed fields are :%s',
-                            'event_espresso'
-                        ),
-                        $field_name,
-                        get_class($this),
-                        implode(', ', array_keys($model_fields))
-                    )
-                );
-            }
-        }
-
-        $date_format     = null;
-        $time_format     = null;
-        $this->_timezone = EEH_DTT_Helper::get_valid_timezone_string($timezone);
-        if (! empty($date_formats) && is_array($date_formats)) {
-            [$date_format, $time_format] = $date_formats;
-        }
-        $this->set_date_format($date_format);
-        $this->set_time_format($time_format);
-        // if db model is instantiating
-        foreach ($model_fields as $fieldName => $field) {
-            if ($bydb) {
-                // client code has indicated these field values are from the database
-                $this->set_from_db(
-                    $fieldName,
-                    $fieldValues[ $fieldName ] ?? null
-                );
-            } else {
-                // we're constructing a brand new instance of the model object.
-                // Generally, this means we'll need to do more field validation
-                $this->set(
-                    $fieldName,
-                    $fieldValues[ $fieldName ] ?? null,
-                    true
-                );
-            }
-        }
-        // remember what values were passed to this constructor
-        $this->_props_n_values_provided_in_constructor = $fieldValues;
-        // remember in entity mapper
-        if (! $bydb && $model->has_primary_key_field() && $this->ID()) {
-            $model->add_to_entity_map($this);
-        }
-        // setup all the relations
-        foreach ($model->relation_settings() as $relation_name => $relation_obj) {
-            if ($relation_obj instanceof EE_Belongs_To_Relation) {
-                $this->_model_relations[ $relation_name ] = null;
-            } else {
-                $this->_model_relations[ $relation_name ] = [];
-            }
-        }
-        /**
-         * Action done at the end of each model object construction
-         *
-         * @param EE_Base_Class $this the model object just created
-         */
-        do_action('AHEE__EE_Base_Class__construct__finished', $this);
-    }
-
-
-    /**
-     * Gets whether or not this model object is allowed to persist/be saved to the database.
-     *
-     * @return boolean
-     */
-    public function allow_persist()
-    {
-        return $this->_allow_persist;
-    }
-
-
-    /**
-     * Sets whether or not this model object should be allowed to be saved to the DB.
-     * Normally once this is set to FALSE you wouldn't set it back to TRUE, unless
-     * you got new information that somehow made you change your mind.
-     *
-     * @param boolean $allow_persist
-     * @return boolean
-     */
-    public function set_allow_persist($allow_persist)
-    {
-        return $this->_allow_persist = $allow_persist;
-    }
-
-
-    /**
-     * Gets the field's original value when this object was constructed during this request.
-     * This can be helpful when determining if a model object has changed or not
-     *
-     * @param string $field_name
-     * @return mixed|null
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_original($field_name)
-    {
-        if (
-            isset($this->_props_n_values_provided_in_constructor[ $field_name ])
-            && $field_settings = $this->get_model()->field_settings_for($field_name)
-        ) {
-            return $field_settings->prepare_for_get($this->_props_n_values_provided_in_constructor[ $field_name ]);
-        }
-        return null;
-    }
-
-
-    /**
-     * @param EE_Base_Class $obj
-     * @return string
-     */
-    public function get_class($obj)
-    {
-        return get_class($obj);
-    }
-
-
-    /**
-     * Overrides parent because parent expects old models.
-     * This also doesn't do any validation, and won't work for serialized arrays
-     *
-     * @param string $field_name
-     * @param mixed  $field_value
-     * @param bool   $use_default
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws Exception
-     */
-    public function set(string $field_name, $field_value, bool $use_default = false)
-    {
-        // if not using default and nothing has changed, and object has already been setup (has ID),
-        // then don't do anything
-        if (
-            ! $use_default
-            && $this->_fields[ $field_name ] === $field_value
-            && $this->ID()
-        ) {
-            return;
-        }
-        $model              = $this->get_model();
-        $this->_has_changes = true;
-        $field_obj          = $model->field_settings_for($field_name);
-        if (! $field_obj instanceof EE_Model_Field_Base) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'A valid EE_Model_Field_Base could not be found for the given field name: %s',
-                        'event_espresso'
-                    ),
-                    $field_name
-                )
-            );
-        }
-        // if ( method_exists( $field_obj, 'set_timezone' )) {
-        if ($field_obj instanceof EE_Datetime_Field) {
-            $field_obj->set_timezone($this->_timezone);
-            $field_obj->set_date_format($this->_dt_frmt);
-            $field_obj->set_time_format($this->_tm_frmt);
-        }
-
-        // should the value be null?
-        $value = $field_value === null && ($use_default || ! $field_obj->is_nullable())
-            ? $field_obj->get_default_value()
-            : $field_value;
-
-        $this->_fields[ $field_name ] = $field_obj->prepare_for_set($value);
-
-        // if we're not in the constructor...
-        // now check if what we set was a primary key
-        if (
-            // note: props_n_values_provided_in_constructor is only set at the END of the constructor
-            $this->_props_n_values_provided_in_constructor
-            && $field_value
-            && $field_name === $model->primary_key_name()
-        ) {
-            // if so, we want all this object's fields to be filled either with
-            // what we've explicitly set on this model
-            // or what we have in the db
-            // echo "setting primary key!";
-            $fields_on_model = self::_get_model(get_class($this))->field_settings();
-            $obj_in_db       = self::_get_model(get_class($this))->get_one_by_ID($field_value);
-            foreach ($fields_on_model as $field_obj) {
-                if (
-                    ! array_key_exists($field_obj->get_name(), $this->_props_n_values_provided_in_constructor)
-                    && $field_obj->get_name() !== $field_name
-                ) {
-                    $this->set($field_obj->get_name(), $obj_in_db->get($field_obj->get_name()));
-                }
-            }
-            // oh this model object has an ID? well make sure its in the entity mapper
-            $model->add_to_entity_map($this);
-        }
-        // let's unset any cache for this field_name from the $_cached_properties property.
-        $this->_clear_cached_property($field_name);
-    }
-
-
-    /**
-     * Overrides parent because parent expects old models.
-     * This also doesn't do any validation, and won't work for serialized arrays
-     *
-     * @param string $field_name
-     * @param mixed  $field_value_from_db
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function set_from_db(string $field_name, $field_value_from_db)
-    {
-        $field_obj = $this->get_model()->field_settings_for($field_name);
-        if ($field_obj instanceof EE_Model_Field_Base) {
-            // you would think the DB has no NULLs for non-null label fields right? wrong!
-            // eg, a CPT model object could have an entry in the posts table, but no
-            // entry in the meta table. Meaning that all its columns in the meta table
-            // are null! yikes! so when we find one like that, use defaults for its meta columns
-            if ($field_value_from_db === null) {
-                if ($field_obj->is_nullable()) {
-                    // if the field allows nulls, then let it be null
-                    $field_value = null;
-                } else {
-                    $field_value = $field_obj->get_default_value();
-                }
-            } else {
-                $field_value = $field_obj->prepare_for_set_from_db($field_value_from_db);
-            }
-            $this->_fields[ $field_name ] = $field_value;
-            $this->_clear_cached_property($field_name);
-        }
-    }
-
-
-    /**
-     * Set custom select values for model.
-     *
-     * @param array $custom_select_values
-     */
-    public function setCustomSelectsValues(array $custom_select_values)
-    {
-        $this->custom_selection_results = $custom_select_values;
-    }
-
-
-    /**
-     * Returns the custom select value for the provided alias if its set.
-     * If not set, returns null.
-     *
-     * @param string $alias
-     * @return string|int|float|null
-     */
-    public function getCustomSelect($alias)
-    {
-        return $this->custom_selection_results[ $alias ] ?? null;
-    }
-
-
-    /**
-     * This sets the field value on the db column if it exists for the given $column_name or
-     * saves it to EE_Extra_Meta if the given $column_name does not match a db column.
-     *
-     * @param string $field_name  Must be the exact column name.
-     * @param mixed  $field_value The value to set.
-     * @return int|bool @see EE_Base_Class::update_extra_meta() for return docs.
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @see EE_message::get_column_value for related documentation on the necessity of this method.
-     */
-    public function set_field_or_extra_meta($field_name, $field_value)
-    {
-        if ($this->get_model()->has_field($field_name)) {
-            $this->set($field_name, $field_value);
-            return true;
-        }
-        // ensure this object is saved first so that extra meta can be properly related.
-        $this->save();
-        return $this->update_extra_meta($field_name, $field_value);
-    }
-
-
-    /**
-     * This retrieves the value of the db column set on this class or if that's not present
-     * it will attempt to retrieve from extra_meta if found.
-     * Example Usage:
-     * Via EE_Message child class:
-     * Due to the dynamic nature of the EE_messages system, EE_messengers will always have a "to",
-     * "from", "subject", and "content" field (as represented in the EE_Message schema), however they may
-     * also have additional main fields specific to the messenger.  The system accommodates those extra
-     * fields through the EE_Extra_Meta table.  This method allows for EE_messengers to retrieve the
-     * value for those extra fields dynamically via the EE_message object.
-     *
-     * @param string $field_name expecting the fully qualified field name.
-     * @return mixed|null  value for the field if found.  null if not found.
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_field_or_extra_meta($field_name)
-    {
-        if ($this->get_model()->has_field($field_name)) {
-            $column_value = $this->get($field_name);
-        } else {
-            // This isn't a column in the main table, let's see if it is in the extra meta.
-            $column_value = $this->get_extra_meta($field_name, true, null);
-        }
-        return $column_value;
-    }
-
-
-    /**
-     * See $_timezone property for description of what the timezone property is for.  This SETS the timezone internally
-     * for being able to reference what timezone we are running conversions on when converting TO the internal timezone
-     * (UTC Unix Timestamp) for the object OR when converting FROM the internal timezone (UTC Unix Timestamp). This is
-     * available to all child classes that may be using the EE_Datetime_Field for a field data type.
-     *
-     * @access public
-     * @param string $timezone A valid timezone string as described by @link http://www.php.net/manual/en/timezones.php
-     * @return void
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @throws Exception
-     */
-    public function set_timezone($timezone = '')
-    {
-        $this->_timezone = EEH_DTT_Helper::get_valid_timezone_string($timezone);
-        // make sure we clear all cached properties because they won't be relevant now
-        $this->_clear_cached_properties();
-        // make sure we update field settings and the date for all EE_Datetime_Fields
-        $model_fields = $this->get_model()->field_settings(false);
-        foreach ($model_fields as $field_name => $field_obj) {
-            if ($field_obj instanceof EE_Datetime_Field) {
-                $field_obj->set_timezone($this->_timezone);
-                if (isset($this->_fields[ $field_name ]) && $this->_fields[ $field_name ] instanceof DateTime) {
-                    EEH_DTT_Helper::setTimezone($this->_fields[ $field_name ], new DateTimeZone($this->_timezone));
-                }
-            }
-        }
-    }
-
-
-    /**
-     * This just returns whatever is set for the current timezone.
-     *
-     * @access public
-     * @return string timezone string
-     */
-    public function get_timezone()
-    {
-        return $this->_timezone;
-    }
-
-
-    /**
-     * This sets the internal date format to what is sent in to be used as the new default for the class
-     * internally instead of wp set date format options
-     *
-     * @param string|null $format should be a format recognizable by PHP date() functions.
-     * @since 4.6
-     */
-    public function set_date_format(?string $format)
-    {
-        $this->_dt_frmt = new DateFormat($format);
-        // clear cached_properties because they won't be relevant now.
-        $this->_clear_cached_properties();
-    }
-
-
-    /**
-     * This sets the internal time format string to what is sent in to be used as the new default for the
-     * class internally instead of wp set time format options.
-     *
-     * @param string|null $format should be a format recognizable by PHP date() functions.
-     * @since 4.6
-     */
-    public function set_time_format(?string $format)
-    {
-        $this->_tm_frmt = new TimeFormat($format);
-        // clear cached_properties because they won't be relevant now.
-        $this->_clear_cached_properties();
-    }
-
-
-    /**
-     * This returns the current internal set format for the date and time formats.
-     *
-     * @param bool $full           if true (default), then return the full format.  Otherwise will return an array
-     *                             where the first value is the date format and the second value is the time format.
-     * @return string|array
-     */
-    public function get_format($full = true)
-    {
-        return $full ? $this->_dt_frmt . ' ' . $this->_tm_frmt : [$this->_dt_frmt, $this->_tm_frmt];
-    }
-
-
-    /**
-     * cache
-     * stores the passed model object on the current model object.
-     * In certain circumstances, we can use this cached model object instead of querying for another one entirely.
-     *
-     * @param string        $relation_name   one of the keys in the _model_relations array on the model. Eg
-     *                                       'Registration' associated with this model object
-     * @param EE_Base_Class $object_to_cache that has a relation to this model object. (Eg, if this is a Transaction,
-     *                                       that could be a payment or a registration)
-     * @param null          $cache_id        a string or number that will be used as the key for any Belongs_To_Many
-     *                                       items which will be stored in an array on this object
-     * @return mixed    index into cache, or just TRUE if the relation is of type Belongs_To (because there's only one
-     *                                       related thing, no array)
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function cache($relation_name = '', $object_to_cache = null, $cache_id = null)
-    {
-        // its entirely possible that there IS no related object yet in which case there is nothing to cache.
-        if (! $object_to_cache instanceof EE_Base_Class) {
-            return false;
-        }
-        // also get "how" the object is related, or throw an error
-        if (! $relationship_to_model = $this->get_model()->related_settings_for($relation_name)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__('There is no relationship to %s on a %s. Cannot cache it', 'event_espresso'),
-                    $relation_name,
-                    get_class($this)
-                )
-            );
-        }
-        // how many things are related ?
-        if ($relationship_to_model instanceof EE_Belongs_To_Relation) {
-            // if it's a "belongs to" relationship, then there's only one related model object
-            // eg, if this is a registration, there's only 1 attendee for it
-            // so for these model objects just set it to be cached
-            $this->_model_relations[ $relation_name ] = $object_to_cache;
-            $return                                   = true;
-        } else {
-            // otherwise, this is the "many" side of a one to many relationship,
-            // so we'll add the object to the array of related objects for that type.
-            // eg: if this is an event, there are many registrations for that event,
-            // so we cache the registrations in an array
-            if (! is_array($this->_model_relations[ $relation_name ])) {
-                // if for some reason, the cached item is a model object,
-                // then stick that in the array, otherwise start with an empty array
-                $this->_model_relations[ $relation_name ] =
-                    $this->_model_relations[ $relation_name ] instanceof EE_Base_Class
-                        ? [$this->_model_relations[ $relation_name ]]
-                        : [];
-            }
-            // first check for a cache_id which is normally empty
-            if (! empty($cache_id)) {
-                // if the cache_id exists, then it means we are purposely trying to cache this
-                // with a known key that can then be used to retrieve the object later on
-                $this->_model_relations[ $relation_name ][ $cache_id ] = $object_to_cache;
-                $return                                                = $cache_id;
-            } elseif ($object_to_cache->ID()) {
-                // OR the cached object originally came from the db, so let's just use it's PK for an ID
-                $this->_model_relations[ $relation_name ][ $object_to_cache->ID() ] = $object_to_cache;
-                $return                                                             = $object_to_cache->ID();
-            } else {
-                // OR it's a new object with no ID, so just throw it in the array with an auto-incremented ID
-                $this->_model_relations[ $relation_name ][] = $object_to_cache;
-                // move the internal pointer to the end of the array
-                end($this->_model_relations[ $relation_name ]);
-                // and grab the key so that we can return it
-                $return = key($this->_model_relations[ $relation_name ]);
-            }
-        }
-        return $return;
-    }
-
-
-    /**
-     * For adding an item to the cached_properties property.
-     *
-     * @access protected
-     * @param string      $fieldname the property item the corresponding value is for.
-     * @param mixed       $value     The value we are caching.
-     * @param string|null $cache_type
-     * @return void
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _set_cached_property($fieldname, $value, $cache_type = null)
-    {
-        // first make sure this property exists
-        $this->get_model()->field_settings_for($fieldname);
-        $cache_type = empty($cache_type) ? 'standard' : $cache_type;
-
-        $this->_cached_properties[ $fieldname ][ $cache_type ] = $value;
-    }
-
-
-    /**
-     * This returns the value cached property if it exists OR the actual property value if the cache doesn't exist.
-     * This also SETS the cache if we return the actual property!
-     *
-     * @param string $fieldname        the name of the property we're trying to retrieve
-     * @param bool   $pretty
-     * @param string $extra_cache_ref  This allows the user to specify an extra cache ref for the given property
-     *                                 (in cases where the same property may be used for different outputs
-     *                                 - i.e. datetime, money etc.)
-     *                                 It can also accept certain pre-defined "schema" strings
-     *                                 to define how to output the property.
-     *                                 see the field's prepare_for_pretty_echoing for what strings can be used
-     * @return mixed                   whatever the value for the property is we're retrieving
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _get_cached_property($fieldname, $pretty = false, $extra_cache_ref = null)
-    {
-        // verify the field exists
-        $model = $this->get_model();
-        $model->field_settings_for($fieldname);
-        $cache_type = $pretty ? 'pretty' : 'standard';
-        $cache_type .= ! empty($extra_cache_ref) ? '_' . $extra_cache_ref : '';
-        if (isset($this->_cached_properties[ $fieldname ][ $cache_type ])) {
-            return $this->_cached_properties[ $fieldname ][ $cache_type ];
-        }
-        $value = $this->_get_fresh_property($fieldname, $pretty, $extra_cache_ref);
-        $this->_set_cached_property($fieldname, $value, $cache_type);
-        return $value;
-    }
-
-
-    /**
-     * If the cache didn't fetch the needed item, this fetches it.
-     *
-     * @param string $fieldname
-     * @param bool   $pretty
-     * @param string $extra_cache_ref
-     * @return mixed
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    protected function _get_fresh_property($fieldname, $pretty = false, $extra_cache_ref = null)
-    {
-        $field_obj = $this->get_model()->field_settings_for($fieldname);
-        // If this is an EE_Datetime_Field we need to make sure timezone, formats, and output are correct
-        if ($field_obj instanceof EE_Datetime_Field) {
-            $this->_prepare_datetime_field($field_obj, $pretty, $extra_cache_ref);
-        }
-        if (! isset($this->_fields[ $fieldname ])) {
-            $this->_fields[ $fieldname ] = null;
-        }
-        return $pretty
-            ? $field_obj->prepare_for_pretty_echoing($this->_fields[ $fieldname ], $extra_cache_ref)
-            : $field_obj->prepare_for_get($this->_fields[ $fieldname ]);
-    }
-
-
-    /**
-     * set timezone, formats, and output for EE_Datetime_Field objects
-     *
-     * @param EE_Datetime_Field $datetime_field
-     * @param bool              $pretty
-     * @param null              $date_or_time
-     * @return void
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     */
-    protected function _prepare_datetime_field(
-        EE_Datetime_Field $datetime_field,
-        $pretty = false,
-        $date_or_time = null
-    ) {
-        $datetime_field->set_timezone($this->_timezone);
-        $datetime_field->set_date_format($this->_dt_frmt, $pretty);
-        $datetime_field->set_time_format($this->_tm_frmt, $pretty);
-        // set the output returned
-        switch ($date_or_time) {
-            case 'D':
-                $datetime_field->set_date_time_output('date');
-                break;
-            case 'T':
-                $datetime_field->set_date_time_output('time');
-                break;
-            default:
-                $datetime_field->set_date_time_output();
-        }
-    }
-
-
-    /**
-     * This just takes care of clearing out the cached_properties
-     *
-     * @return void
-     */
-    protected function _clear_cached_properties()
-    {
-        $this->_cached_properties = [];
-    }
-
-
-    /**
-     * This just clears out ONE property if it exists in the cache
-     *
-     * @param string $property_name the property to remove if it exists (from the _cached_properties array)
-     * @return void
-     */
-    protected function _clear_cached_property($property_name)
-    {
-        if (isset($this->_cached_properties[ $property_name ])) {
-            unset($this->_cached_properties[ $property_name ]);
-        }
-    }
-
-
-    /**
-     * Ensures that this related thing is a model object.
-     *
-     * @param mixed  $object_or_id EE_base_Class/int/string either a related model object, or its ID
-     * @param string $model_name   name of the related thing, eg 'Attendee',
-     * @return EE_Base_Class
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function ensure_related_thing_is_model_obj($object_or_id, $model_name)
-    {
-        $other_model_instance = self::_get_model_instance_with_name(
-            self::_get_model_classname($model_name),
-            $this->_timezone
-        );
-        return $other_model_instance->ensure_is_obj($object_or_id);
-    }
-
-
-    /**
-     * Forgets the cached model of the given relation Name. So the next time we request it,
-     * we will fetch it again from the database. (Handy if you know it's changed somehow).
-     * If a specific object is supplied, and the relationship to it is either a HasMany or HABTM,
-     * then only remove that one object from our cached array. Otherwise, clear the entire list
-     *
-     * @param string $relation_name                        one of the keys in the _model_relations array on the model.
-     *                                                     Eg 'Registration'
-     * @param mixed  $object_to_remove_or_index_into_array or an index into the array of cached things, or NULL
-     *                                                     if you intend to use $clear_all = TRUE, or the relation only
-     *                                                     has 1 object anyways (ie, it's a BelongsToRelation)
-     * @param bool   $clear_all                            This flags clearing the entire cache relation property if
-     *                                                     this is HasMany or HABTM.
-     * @return EE_Base_Class | boolean from which was cleared from the cache, or true if we requested to remove a
-     *                                                     relation from all
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function clear_cache($relation_name, $object_to_remove_or_index_into_array = null, $clear_all = false)
-    {
-        $relationship_to_model = $this->get_model()->related_settings_for($relation_name);
-        $index_in_cache        = '';
-        if (! $relationship_to_model) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__('There is no relationship to %s on a %s. Cannot clear that cache', 'event_espresso'),
-                    $relation_name,
-                    get_class($this)
-                )
-            );
-        }
-        if ($clear_all) {
-            $obj_removed                              = true;
-            $this->_model_relations[ $relation_name ] = null;
-        } elseif ($relationship_to_model instanceof EE_Belongs_To_Relation) {
-            $obj_removed                              = $this->_model_relations[ $relation_name ];
-            $this->_model_relations[ $relation_name ] = null;
-        } else {
-            if (
-                $object_to_remove_or_index_into_array instanceof EE_Base_Class
-                && $object_to_remove_or_index_into_array->ID()
-            ) {
-                $index_in_cache = $object_to_remove_or_index_into_array->ID();
-                if (
-                    is_array($this->_model_relations[ $relation_name ])
-                    && ! isset($this->_model_relations[ $relation_name ][ $index_in_cache ])
-                ) {
-                    $index_found_at = null;
-                    // find this object in the array even though it has a different key
-                    foreach ($this->_model_relations[ $relation_name ] as $index => $obj) {
-                        /** @noinspection TypeUnsafeComparisonInspection */
-                        if (
-                            $obj instanceof EE_Base_Class
-                            && (
-                                $obj == $object_to_remove_or_index_into_array
-                                || $obj->ID() === $object_to_remove_or_index_into_array->ID()
-                            )
-                        ) {
-                            $index_found_at = $index;
-                            break;
-                        }
-                    }
-                    if ($index_found_at) {
-                        $index_in_cache = $index_found_at;
-                    } else {
-                        // it wasn't found. huh. well obviously it doesn't need to be removed from teh cache
-                        // if it wasn't in it to begin with. So we're done
-                        return $object_to_remove_or_index_into_array;
-                    }
-                }
-            } elseif ($object_to_remove_or_index_into_array instanceof EE_Base_Class) {
-                // so they provided a model object, but it's not yet saved to the DB... so let's go hunting for it!
-                foreach ($this->get_all_from_cache($relation_name) as $index => $potentially_obj_we_want) {
-                    /** @noinspection TypeUnsafeComparisonInspection */
-                    if ($potentially_obj_we_want == $object_to_remove_or_index_into_array) {
-                        $index_in_cache = $index;
-                    }
-                }
-            } else {
-                $index_in_cache = $object_to_remove_or_index_into_array;
-            }
-            // supposedly we've found it. But it could just be that the client code
-            // provided a bad index/object
-            if (isset($this->_model_relations[ $relation_name ][ $index_in_cache ])) {
-                $obj_removed = $this->_model_relations[ $relation_name ][ $index_in_cache ];
-                unset($this->_model_relations[ $relation_name ][ $index_in_cache ]);
-            } else {
-                // that thing was never cached anyways.
-                $obj_removed = null;
-            }
-        }
-        return $obj_removed;
-    }
-
-
-    /**
-     * update_cache_after_object_save
-     * Allows a cached item to have it's cache ID (within the array of cached items) reset using the new ID it has
-     * obtained after being saved to the db
-     *
-     * @param string        $relation_name      - the type of object that is cached
-     * @param EE_Base_Class $newly_saved_object - the newly saved object to be re-cached
-     * @param string        $current_cache_id   - the ID that was used when originally caching the object
-     * @return boolean TRUE on success, FALSE on fail
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function update_cache_after_object_save(
-        $relation_name,
-        EE_Base_Class $newly_saved_object,
-        $current_cache_id = ''
-    ) {
-        // verify that incoming object is of the correct type
-        $obj_class = 'EE_' . $relation_name;
-        if ($newly_saved_object instanceof $obj_class) {
-            /* @type EE_Base_Class $newly_saved_object */
-            // now get the type of relation
-            $relationship_to_model = $this->get_model()->related_settings_for($relation_name);
-            // if this is a 1:1 relationship
-            if ($relationship_to_model instanceof EE_Belongs_To_Relation) {
-                // then just replace the cached object with the newly saved object
-                $this->_model_relations[ $relation_name ] = $newly_saved_object;
-                return true;
-                // or if it's some kind of sordid feral polyamorous relationship...
-            }
-            if (
-                is_array($this->_model_relations[ $relation_name ])
-                && isset($this->_model_relations[ $relation_name ][ $current_cache_id ])
-            ) {
-                // then remove the current cached item
-                unset($this->_model_relations[ $relation_name ][ $current_cache_id ]);
-                // and cache the newly saved object using it's new ID
-                $this->_model_relations[ $relation_name ][ $newly_saved_object->ID() ] = $newly_saved_object;
-                return true;
-            }
-        }
-        return false;
-    }
-
-
-    /**
-     * Fetches a single EE_Base_Class on that relation. (If the relation is of type
-     * BelongsTo, it will only ever have 1 object. However, other relations could have an array of objects)
-     *
-     * @param string $relation_name
-     * @return EE_Base_Class
-     */
-    public function get_one_from_cache($relation_name)
-    {
-        $cached_array_or_object = $this->_model_relations[ $relation_name ] ?? null;
-        if (is_array($cached_array_or_object)) {
-            return array_shift($cached_array_or_object);
-        }
-        return $cached_array_or_object;
-    }
-
-
-    /**
-     * Fetches a single EE_Base_Class on that relation. (If the relation is of type
-     * BelongsTo, it will only ever have 1 object. However, other relations could have an array of objects)
-     *
-     * @param string $relation_name
-     * @return EE_Base_Class[] NOT necessarily indexed by primary keys
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function get_all_from_cache($relation_name)
-    {
-        $objects = $this->_model_relations[ $relation_name ] ?? [];
-        // if the result is not an array, but exists, make it an array
-        $objects = is_array($objects)
-            ? $objects
-            : [$objects];
-        // bugfix for https://events.codebasehq.com/projects/event-espresso/tickets/7143
-        // basically, if this model object was stored in the session, and these cached model objects
-        // already have IDs, let's make sure they're in their model's entity mapper
-        // otherwise we will have duplicates next time we call
-        // EE_Registry::instance()->load_model( $relation_name )->get_one_by_ID( $result->ID() );
-        $model = EE_Registry::instance()->load_model($relation_name);
-        foreach ($objects as $model_object) {
-            if ($model instanceof EEM_Base && $model_object instanceof EE_Base_Class) {
-                // ensure its in the map if it has an ID; otherwise it will be added to the map when its saved
-                if ($model_object->ID()) {
-                    $model->add_to_entity_map($model_object);
-                }
-            } else {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            'Error retrieving related model objects. Either $1%s is not a model or $2%s is not a model object',
-                            'event_espresso'
-                        ),
-                        $relation_name,
-                        gettype($model_object)
-                    )
-                );
-            }
-        }
-        return $objects;
-    }
-
-
-    /**
-     * Returns the next x number of EE_Base_Class objects in sequence from this object as found in the database
-     * matching the given query conditions.
-     *
-     * @param null  $field_to_order_by  What field is being used as the reference point.
-     * @param int   $limit              How many objects to return.
-     * @param array $query_params       Any additional conditions on the query.
-     * @param null  $columns_to_select  If left null, then an array of EE_Base_Class objects is returned, otherwise
-     *                                  you can indicate just the columns you want returned
-     * @return array|EE_Base_Class[]
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function next_x($field_to_order_by = null, $limit = 1, $query_params = [], $columns_to_select = null)
-    {
-        $model         = $this->get_model();
-        $field         = empty($field_to_order_by) && $model->has_primary_key_field()
-            ? $model->get_primary_key_field()->get_name()
-            : $field_to_order_by;
-        $current_value = ! empty($field)
-            ? $this->get($field)
-            : null;
-        if (empty($field) || empty($current_value)) {
-            return [];
-        }
-        return $model->next_x($current_value, $field, $limit, $query_params, $columns_to_select);
-    }
-
-
-    /**
-     * Returns the previous x number of EE_Base_Class objects in sequence from this object as found in the database
-     * matching the given query conditions.
-     *
-     * @param null  $field_to_order_by  What field is being used as the reference point.
-     * @param int   $limit              How many objects to return.
-     * @param array $query_params       Any additional conditions on the query.
-     * @param null  $columns_to_select  If left null, then an array of EE_Base_Class objects is returned, otherwise
-     *                                  you can indicate just the columns you want returned
-     * @return array|EE_Base_Class[]
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function previous_x(
-        $field_to_order_by = null,
-        $limit = 1,
-        $query_params = [],
-        $columns_to_select = null
-    ) {
-        $model         = $this->get_model();
-        $field         = empty($field_to_order_by) && $model->has_primary_key_field()
-            ? $model->get_primary_key_field()->get_name()
-            : $field_to_order_by;
-        $current_value = ! empty($field) ? $this->get($field) : null;
-        if (empty($field) || empty($current_value)) {
-            return [];
-        }
-        return $model->previous_x($current_value, $field, $limit, $query_params, $columns_to_select);
-    }
-
-
-    /**
-     * Returns the next EE_Base_Class object in sequence from this object as found in the database
-     * matching the given query conditions.
-     *
-     * @param null  $field_to_order_by  What field is being used as the reference point.
-     * @param array $query_params       Any additional conditions on the query.
-     * @param null  $columns_to_select  If left null, then an array of EE_Base_Class objects is returned, otherwise
-     *                                  you can indicate just the columns you want returned
-     * @return array|EE_Base_Class
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function next($field_to_order_by = null, $query_params = [], $columns_to_select = null)
-    {
-        $model         = $this->get_model();
-        $field         = empty($field_to_order_by) && $model->has_primary_key_field()
-            ? $model->get_primary_key_field()->get_name()
-            : $field_to_order_by;
-        $current_value = ! empty($field) ? $this->get($field) : null;
-        if (empty($field) || empty($current_value)) {
-            return [];
-        }
-        return $model->next($current_value, $field, $query_params, $columns_to_select);
-    }
-
-
-    /**
-     * Returns the previous EE_Base_Class object in sequence from this object as found in the database
-     * matching the given query conditions.
-     *
-     * @param null  $field_to_order_by  What field is being used as the reference point.
-     * @param array $query_params       Any additional conditions on the query.
-     * @param null  $columns_to_select  If left null, then an EE_Base_Class object is returned, otherwise
-     *                                  you can indicate just the column you want returned
-     * @return array|EE_Base_Class
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function previous($field_to_order_by = null, $query_params = [], $columns_to_select = null)
-    {
-        $model         = $this->get_model();
-        $field         = empty($field_to_order_by) && $model->has_primary_key_field()
-            ? $model->get_primary_key_field()->get_name()
-            : $field_to_order_by;
-        $current_value = ! empty($field) ? $this->get($field) : null;
-        if (empty($field) || empty($current_value)) {
-            return [];
-        }
-        return $model->previous($current_value, $field, $query_params, $columns_to_select);
-    }
-
-
-    /**
-     * verifies that the specified field is of the correct type
-     *
-     * @param string $field_name
-     * @param string $extra_cache_ref This allows the user to specify an extra cache ref for the given property
-     *                                (in cases where the same property may be used for different outputs
-     *                                - i.e. datetime, money etc.)
-     * @return mixed
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get($field_name, $extra_cache_ref = null)
-    {
-        return $this->_get_cached_property($field_name, false, $extra_cache_ref);
-    }
-
-
-    /**
-     * This method simply returns the RAW unprocessed value for the given property in this class
-     *
-     * @param string $field_name A valid fieldname
-     * @return mixed              Whatever the raw value stored on the property is.
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error if fieldSettings is misconfigured or the field doesn't exist.
-     */
-    public function get_raw($field_name)
-    {
-        $field_settings = $this->get_model()->field_settings_for($field_name);
-        return $field_settings instanceof EE_Datetime_Field && $this->_fields[ $field_name ] instanceof DateTime
-            ? $this->_fields[ $field_name ]->format('U')
-            : $this->_fields[ $field_name ];
-    }
-
-
-    /**
-     * This is used to return the internal DateTime object used for a field that is a
-     * EE_Datetime_Field.
-     *
-     * @param string $field_name               The field name retrieving the DateTime object.
-     * @return mixed null | false | DateTime  If the requested field is NOT a EE_Datetime_Field then
-     * @throws EE_Error an error is set and false returned.  If the field IS an
-     *                                         EE_Datetime_Field and but the field value is null, then
-     *                                         just null is returned (because that indicates that likely
-     *                                         this field is nullable).
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     */
-    public function get_DateTime_object($field_name)
-    {
-        $field_settings = $this->get_model()->field_settings_for($field_name);
-        if (! $field_settings instanceof EE_Datetime_Field) {
-            EE_Error::add_error(
-                sprintf(
-                    esc_html__(
-                        'The field %s is not an EE_Datetime_Field field.  There is no DateTime object stored on this field type.',
-                        'event_espresso'
-                    ),
-                    $field_name
-                ),
-                __FILE__,
-                __FUNCTION__,
-                __LINE__
-            );
-            return false;
-        }
-        return isset($this->_fields[ $field_name ]) && $this->_fields[ $field_name ] instanceof DateTime
-            ? clone $this->_fields[ $field_name ]
-            : null;
-    }
-
-
-    /**
-     * To be used in template to immediately echo out the value, and format it for output.
-     * Eg, should call stripslashes and whatnot before echoing
-     *
-     * @param string $field_name      the name of the field as it appears in the DB
-     * @param string $extra_cache_ref This allows the user to specify an extra cache ref for the given property
-     *                                (in cases where the same property may be used for different outputs
-     *                                - i.e. datetime, money etc.)
-     * @return void
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e($field_name, $extra_cache_ref = null)
-    {
-        echo wp_kses($this->get_pretty($field_name, $extra_cache_ref), AllowedTags::getWithFormTags());
-    }
-
-
-    /**
-     * Exactly like e(), echoes out the field, but sets its schema to 'form_input', so that it
-     * can be easily used as the value of form input.
-     *
-     * @param string $field_name
-     * @return void
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function f($field_name)
-    {
-        $this->e($field_name, 'form_input');
-    }
-
-
-    /**
-     * Same as `f()` but just returns the value instead of echoing it
-     *
-     * @param string $field_name
-     * @return string
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_f($field_name)
-    {
-        return (string) $this->get_pretty($field_name, 'form_input');
-    }
-
-
-    /**
-     * Gets a pretty view of the field's value. $extra_cache_ref can specify different formats for this.
-     * The $extra_cache_ref will be passed to the model field's prepare_for_pretty_echoing, so consult the field's class
-     * to see what options are available.
-     *
-     * @param string $field_name
-     * @param string $extra_cache_ref This allows the user to specify an extra cache ref for the given property
-     *                                (in cases where the same property may be used for different outputs
-     *                                - i.e. datetime, money etc.)
-     * @return mixed
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_pretty($field_name, $extra_cache_ref = null)
-    {
-        return $this->_get_cached_property($field_name, true, $extra_cache_ref);
-    }
-
-
-    /**
-     * This simply returns the datetime for the given field name
-     * Note: this protected function is called by the wrapper get_date or get_time or get_datetime functions
-     * (and the equivalent e_date, e_time, e_datetime).
-     *
-     * @access   protected
-     * @param string      $field_name   Field on the instantiated EE_Base_Class child object
-     * @param string|null $date_format  valid datetime format used for date
-     *                                  (if '' then we just use the default on the field,
-     *                                  if NULL we use the last-used format)
-     * @param string|null $time_format  Same as above except this is for time format
-     * @param string|null $date_or_time if NULL then both are returned, otherwise "D" = only date and "T" = only time.
-     * @param bool|null   $echo         Whether the datetime is pretty echoing or just returned using vanilla get
-     * @return string|bool|EE_Error string on success, FALSE on fail, or EE_Error Exception is thrown
-     *                                  if field is not a valid dtt field, or void if echoing
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    protected function _get_datetime(
-        string $field_name,
-        ?string $date_format = '',
-        ?string $time_format = '',
-        ?string $date_or_time = '',
-        ?bool $echo = false
-    ) {
-        // clear cached property
-        $this->_clear_cached_property($field_name);
-        // reset format properties because they are used in get()
-        $this->_dt_frmt = $date_format ?: $this->_dt_frmt;
-        $this->_tm_frmt = $time_format ?: $this->_tm_frmt;
-        if ($echo) {
-            $this->e($field_name, $date_or_time);
-            return '';
-        }
-        return $this->get($field_name, $date_or_time);
-    }
-
-
-    /**
-     * below are wrapper functions for the various datetime outputs that can be obtained for JUST returning the date
-     * portion of a datetime value. (note the only difference between get_ and e_ is one returns the value and the
-     * other echoes the pretty value for dtt)
-     *
-     * @param string $field_name name of model object datetime field holding the value
-     * @param string $format     format for the date returned (if NULL we use default in dt_frmt property)
-     * @return string            datetime value formatted
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_date($field_name, $format = '')
-    {
-        return $this->_get_datetime($field_name, $format, null, 'D');
-    }
-
-
-    /**
-     * @param        $field_name
-     * @param string $format
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e_date($field_name, $format = '')
-    {
-        $this->_get_datetime($field_name, $format, null, 'D', true);
-    }
-
-
-    /**
-     * below are wrapper functions for the various datetime outputs that can be obtained for JUST returning the time
-     * portion of a datetime value. (note the only difference between get_ and e_ is one returns the value and the
-     * other echoes the pretty value for dtt)
-     *
-     * @param string $field_name name of model object datetime field holding the value
-     * @param string $format     format for the time returned ( if NULL we use default in tm_frmt property)
-     * @return string             datetime value formatted
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_time($field_name, $format = '')
-    {
-        return $this->_get_datetime($field_name, null, $format, 'T');
-    }
-
-
-    /**
-     * @param        $field_name
-     * @param string $format
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e_time($field_name, $format = '')
-    {
-        $this->_get_datetime($field_name, null, $format, 'T', true);
-    }
-
-
-    /**
-     * below are wrapper functions for the various datetime outputs that can be obtained for returning the date AND
-     * time portion of a datetime value. (note the only difference between get_ and e_ is one returns the value and the
-     * other echoes the pretty value for dtt)
-     *
-     * @param string $field_name  name of model object datetime field holding the value
-     * @param string $date_format format for the date returned (if NULL we use default in dt_frmt property)
-     * @param string $time_format format for the time returned (if NULL we use default in tm_frmt property)
-     * @return string             datetime value formatted
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_datetime($field_name, $date_format = '', $time_format = '')
-    {
-        return $this->_get_datetime($field_name, $date_format, $time_format);
-    }
-
-
-    /**
-     * @param string $field_name
-     * @param string $date_format
-     * @param string $time_format
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function e_datetime($field_name, $date_format = '', $time_format = '')
-    {
-        $this->_get_datetime($field_name, $date_format, $time_format, null, true);
-    }
-
-
-    /**
-     * Get the i8ln value for a date using the WordPress @param string $field_name The EE_Datetime_Field reference for
-     *                           the date being retrieved.
-     *
-     * @param string $format     PHP valid date/time string format.  If none is provided then the internal set format
-     *                           on the object will be used.
-     * @return string Date and time string in set locale or false if no field exists for the given
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     *                           field name.
-     * @see date_i18n function.
-     */
-    public function get_i18n_datetime(string $field_name, string $format = ''): string
-    {
-        $format = empty($format) ? $this->_dt_frmt . ' ' . $this->_tm_frmt : $format;
-        return date_i18n(
-            $format,
-            EEH_DTT_Helper::get_timestamp_with_offset(
-                $this->get_raw($field_name),
-                $this->_timezone
-            )
-        );
-    }
-
-
-    /**
-     * This method validates whether the given field name is a valid field on the model object as well as it is of a
-     * type EE_Datetime_Field.  On success there will be returned the field settings.  On fail an EE_Error exception is
-     * thrown.
-     *
-     * @param string $field_name The field name being checked
-     * @return EE_Datetime_Field
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    protected function _get_dtt_field_settings($field_name)
-    {
-        $field = $this->get_model()->field_settings_for($field_name);
-        // check if field is dtt
-        if ($field instanceof EE_Datetime_Field) {
-            return $field;
-        }
-        throw new EE_Error(
-            sprintf(
-                esc_html__(
-                    'The field name "%s" has been requested for the EE_Base_Class datetime functions and it is not a valid EE_Datetime_Field.  Please check the spelling of the field and make sure it has been setup as a EE_Datetime_Field in the %s model constructor',
-                    'event_espresso'
-                ),
-                $field_name,
-                self::_get_model_classname(get_class($this))
-            )
-        );
-    }
-
-
-
-
-    /**
-     * NOTE ABOUT BELOW:
-     * These convenience date and time setters are for setting date and time independently.  In other words you might
-     * want to change the time on a datetime_field but leave the date the same (or vice versa). IF on the other hand
-     * you want to set both date and time at the same time, you can just use the models default set($fieldname,$value)
-     * method and make sure you send the entire datetime value for setting.
-     */
-    /**
-     * sets the time on a datetime property
-     *
-     * @access protected
-     * @param string|Datetime $time      a valid time string for php datetime functions (or DateTime object)
-     * @param string          $fieldname the name of the field the time is being set on (must match a EE_Datetime_Field)
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _set_time_for($time, $fieldname)
-    {
-        $this->_set_date_time('T', $time, $fieldname);
-    }
-
-
-    /**
-     * sets the date on a datetime property
-     *
-     * @access protected
-     * @param string|DateTime $date      a valid date string for php datetime functions ( or DateTime object)
-     * @param string          $fieldname the name of the field the date is being set on (must match a EE_Datetime_Field)
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _set_date_for($date, $fieldname)
-    {
-        $this->_set_date_time('D', $date, $fieldname);
-    }
-
-
-    /**
-     * This takes care of setting a date or time independently on a given model object property. This method also
-     * verifies that the given field_name matches a model object property and is for a EE_Datetime_Field field
-     *
-     * @access protected
-     * @param string          $what           "T" for time, 'B' for both, 'D' for Date.
-     * @param string|DateTime $datetime_value A valid Date or Time string (or DateTime object)
-     * @param string          $field_name     the name of the field the date OR time is being set on (must match a
-     *                                        EE_Datetime_Field property)
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _set_date_time(string $what, $datetime_value, string $field_name)
-    {
-        $field = $this->_get_dtt_field_settings($field_name);
-        $field->set_timezone($this->_timezone);
-        $field->set_date_format($this->_dt_frmt);
-        $field->set_time_format($this->_tm_frmt);
-        switch ($what) {
-            case 'T':
-                $this->_fields[ $field_name ] = $field->prepare_for_set_with_new_time(
-                    $datetime_value,
-                    $this->_fields[ $field_name ]
-                );
-                $this->_has_changes           = true;
-                break;
-            case 'D':
-                $this->_fields[ $field_name ] = $field->prepare_for_set_with_new_date(
-                    $datetime_value,
-                    $this->_fields[ $field_name ]
-                );
-                $this->_has_changes           = true;
-                break;
-            case 'B':
-                $this->_fields[ $field_name ] = $field->prepare_for_set($datetime_value);
-                $this->_has_changes           = true;
-                break;
-        }
-        $this->_clear_cached_property($field_name);
-    }
-
-
-    /**
-     * This will return a timestamp for the website timezone but ONLY when the current website timezone is different
-     * than the timezone set for the website. NOTE, this currently only works well with methods that return values.  If
-     * you use it with methods that echo values the $_timestamp property may not get reset to its original value and
-     * that could lead to some unexpected results!
-     *
-     * @access public
-     * @param string $field_name               This is the name of the field on the object that contains the date/time
-     *                                         value being returned.
-     * @param string $callback                 must match a valid method in this class (defaults to get_datetime)
-     * @param mixed (array|string) $args       This is the arguments that will be passed to the callback.
-     * @param string $prepend                  You can include something to prepend on the timestamp
-     * @param string $append                   You can include something to append on the timestamp
-     * @return string timestamp
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function display_in_my_timezone(
-        $field_name,
-        $callback = 'get_datetime',
-        $args = null,
-        $prepend = '',
-        $append = ''
-    ) {
-        $timezone = EEH_DTT_Helper::get_timezone();
-        if ($timezone === $this->_timezone) {
-            return '';
-        }
-        $original_timezone = $this->_timezone;
-        $this->set_timezone($timezone);
-        $fn   = (array) $field_name;
-        $args = array_merge($fn, (array) $args);
-        if (! method_exists($this, $callback)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'The method named "%s" given as the callback param in "display_in_my_timezone" does not exist.  Please check your spelling',
-                        'event_espresso'
-                    ),
-                    $callback
-                )
-            );
-        }
-        $args   = (array) $args;
-        $return = $prepend . call_user_func_array([$this, $callback], $args) . $append;
-        $this->set_timezone($original_timezone);
-        return $return;
-    }
-
-
-    /**
-     * Deletes this model object.
-     * This calls the `EE_Base_Class::_delete` method.  Child classes wishing to change default behaviour should
-     * override
-     * `EE_Base_Class::_delete` NOT this class.
-     *
-     * @return boolean | int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function delete()
-    {
-        /**
-         * Called just before the `EE_Base_Class::_delete` method call.
-         * Note:
-         * `EE_Base_Class::_delete` might be overridden by child classes so any client code hooking into these actions
-         * should be aware that `_delete` may not always result in a permanent delete.
-         * For example, `EE_Soft_Delete_Base_Class::_delete`
-         * soft deletes (trash) the object and does not permanently delete it.
-         *
-         * @param EE_Base_Class $model_object about to be 'deleted'
-         */
-        do_action('AHEE__EE_Base_Class__delete__before', $this);
-        $result = $this->_delete();
-        /**
-         * Called just after the `EE_Base_Class::_delete` method call.
-         * Note:
-         * `EE_Base_Class::_delete` might be overridden by child classes so any client code hooking into these actions
-         * should be aware that `_delete` may not always result in a permanent delete.
-         * For example `EE_Soft_Base_Class::_delete`
-         * soft deletes (trash) the object and does not permanently delete it.
-         *
-         * @param EE_Base_Class $model_object that was just 'deleted'
-         * @param boolean       $result
-         */
-        do_action('AHEE__EE_Base_Class__delete__end', $this, $result);
-        return $result;
-    }
-
-
-    /**
-     * Calls the specific delete method for the instantiated class.
-     * This method is called by the public `EE_Base_Class::delete` method.  Any child classes desiring to override
-     * default functionality for "delete" (which is to call `permanently_delete`) should override this method NOT
-     * `EE_Base_Class::delete`
-     *
-     * @return bool|int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _delete()
-    {
-        return $this->delete_permanently();
-    }
-
-
-    /**
-     * Deletes this model object permanently from db
-     * (but keep in mind related models may block the delete and return an error)
-     *
-     * @return bool | int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function delete_permanently()
-    {
-        /**
-         * Called just before HARD deleting a model object
-         *
-         * @param EE_Base_Class $model_object about to be 'deleted'
-         */
-        do_action('AHEE__EE_Base_Class__delete_permanently__before', $this);
-        $model  = $this->get_model();
-        $result = $model->delete_permanently_by_ID($this->ID());
-        $this->refresh_cache_of_related_objects();
-        /**
-         * Called just after HARD deleting a model object
-         *
-         * @param EE_Base_Class $model_object that was just 'deleted'
-         * @param boolean       $result
-         */
-        do_action('AHEE__EE_Base_Class__delete_permanently__end', $this, $result);
-        return $result;
-    }
-
-
-    /**
-     * When this model object is deleted, it may still be cached on related model objects. This clears the cache of
-     * related model objects
-     *
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function refresh_cache_of_related_objects()
-    {
-        $model = $this->get_model();
-        foreach ($model->relation_settings() as $relation_name => $relation_obj) {
-            if (! empty($this->_model_relations[ $relation_name ])) {
-                $related_objects = $this->_model_relations[ $relation_name ];
-                if ($relation_obj instanceof EE_Belongs_To_Relation) {
-                    // this relation only stores a single model object, not an array
-                    // but let's make it consistent
-                    $related_objects = [$related_objects];
-                }
-                foreach ($related_objects as $related_object) {
-                    // only refresh their cache if they're in memory
-                    if ($related_object instanceof EE_Base_Class) {
-                        $related_object->clear_cache(
-                            $model->get_this_model_name(),
-                            $this
-                        );
-                    }
-                }
-            }
-        }
-    }
-
-
-    /**
-     *        Saves this object to the database. An array may be supplied to set some values on this
-     * object just before saving.
-     *
-     * @access public
-     * @param array $set_cols_n_values keys are field names, values are their new values,
-     *                                 if provided during the save() method (often client code will change the fields'
-     *                                 values before calling save)
-     * @return bool|int|string         1 on a successful update
-     *                                 the ID of the new entry on insert
-     *                                 0 on failure or if the model object isn't allowed to persist
-     *                                 (as determined by EE_Base_Class::allow_persist())
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws ReflectionException
-     */
-    public function save($set_cols_n_values = [])
-    {
-        $model = $this->get_model();
-        /**
-         * Filters the fields we're about to save on the model object
-         *
-         * @param array         $set_cols_n_values
-         * @param EE_Base_Class $model_object
-         */
-        $set_cols_n_values = (array) apply_filters(
-            'FHEE__EE_Base_Class__save__set_cols_n_values',
-            $set_cols_n_values,
-            $this
-        );
-        // set attributes as provided in $set_cols_n_values
-        foreach ($set_cols_n_values as $column => $value) {
-            $this->set($column, $value);
-        }
-        // no changes ? then don't do anything
-        if (! $this->_has_changes && $this->ID() && $model->get_primary_key_field()->is_auto_increment()) {
-            return 0;
-        }
-        /**
-         * Saving a model object.
-         * Before we perform a save, this action is fired.
-         *
-         * @param EE_Base_Class $model_object the model object about to be saved.
-         */
-        do_action('AHEE__EE_Base_Class__save__begin', $this);
-        if (! $this->allow_persist()) {
-            return 0;
-        }
-        // now get current attribute values
-        $save_cols_n_values = $this->_fields;
-        // if the object already has an ID, update it. Otherwise, insert it
-        // also: change the assumption about values passed to the model NOT being prepare dby the model object.
-        // They have been
-        $old_assumption_concerning_value_preparation = $model
-            ->get_assumption_concerning_values_already_prepared_by_model_object();
-        $model->assume_values_already_prepared_by_model_object(true);
-        // does this model have an autoincrement PK?
-        if ($model->has_primary_key_field()) {
-            if ($model->get_primary_key_field()->is_auto_increment()) {
-                // ok check if it's set, if so: update; if not, insert
-                if (! empty($save_cols_n_values[ $model->primary_key_name() ])) {
-                    $results = $model->update_by_ID($save_cols_n_values, $this->ID());
-                } else {
-                    unset($save_cols_n_values[ $model->primary_key_name() ]);
-                    $results = $model->insert($save_cols_n_values);
-                    if ($results) {
-                        // if successful, set the primary key
-                        // but don't use the normal SET method, because it will check if
-                        // an item with the same ID exists in the mapper & db, then
-                        // will find it in the db (because we just added it) and THAT object
-                        // will get added to the mapper before we can add this one!
-                        // but if we just avoid using the SET method, all that headache can be avoided
-                        $pk_field_name                   = $model->primary_key_name();
-                        $this->_fields[ $pk_field_name ] = $results;
-                        $this->_clear_cached_property($pk_field_name);
-                        $model->add_to_entity_map($this);
-                        $this->_update_cached_related_model_objs_fks();
-                    }
-                }
-            } else {// PK is NOT auto-increment
-                // so check if one like it already exists in the db
-                if ($model->exists_by_ID($this->ID())) {
-                    if (WP_DEBUG && ! $this->in_entity_map()) {
-                        throw new EE_Error(
-                            sprintf(
-                                esc_html__(
-                                    'Using a model object %1$s that is NOT in the entity map, can lead to unexpected errors. You should either: %4$s 1. Put it in the entity mapper by calling %2$s %4$s 2. Discard this model object and use what is in the entity mapper %4$s 3. Fetch from the database using %3$s',
-                                    'event_espresso'
-                                ),
-                                get_class($this),
-                                get_class($model) . '::instance()->add_to_entity_map()',
-                                get_class($model) . '::instance()->get_one_by_ID()',
-                                '<br />'
-                            )
-                        );
-                    }
-                    $results = $model->update_by_ID($save_cols_n_values, $this->ID());
-                } else {
-                    $results = $model->insert($save_cols_n_values);
-                    $this->_update_cached_related_model_objs_fks();
-                }
-            }
-        } else {// there is NO primary key
-            $already_in_db = false;
-            foreach ($model->unique_indexes() as $index) {
-                $uniqueness_where_params = array_intersect_key($save_cols_n_values, $index->fields());
-                if ($model->exists([$uniqueness_where_params])) {
-                    $already_in_db = true;
-                }
-            }
-            if ($already_in_db) {
-                $combined_pk_fields_n_values = array_intersect_key(
-                    $save_cols_n_values,
-                    $model->get_combined_primary_key_fields()
-                );
-                $results                     = $model->update(
-                    $save_cols_n_values,
-                    $combined_pk_fields_n_values
-                );
-            } else {
-                $results = $model->insert($save_cols_n_values);
-            }
-        }
-        // restore the old assumption about values being prepared by the model object
-        $model->assume_values_already_prepared_by_model_object(
-            $old_assumption_concerning_value_preparation
-        );
-        /**
-         * After saving the model object this action is called
-         *
-         * @param EE_Base_Class $model_object which was just saved
-         * @param boolean|int   $results      if it were updated, TRUE or FALSE; if it were newly inserted
-         *                                    the new ID (or 0 if an error occurred and it wasn't updated)
-         */
-        do_action('AHEE__EE_Base_Class__save__end', $this, $results);
-        $this->_has_changes = false;
-        return $results;
-    }
-
-
-    /**
-     * Updates the foreign key on related models objects pointing to this to have this model object's ID
-     * as their foreign key.  If the cached related model objects already exist in the db, saves them (so that the DB
-     * is consistent) Especially useful in case we JUST added this model object ot the database and we want to let its
-     * cached relations with foreign keys to it know about that change. Eg: we've created a transaction but haven't
-     * saved it to the db. We also create a registration and don't save it to the DB, but we DO cache it on the
-     * transaction. Now, when we save the transaction, the registration's TXN_ID will be automatically updated, whether
-     * or not they exist in the DB (if they do, their DB records will be automatically updated)
-     *
-     * @return void
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected function _update_cached_related_model_objs_fks()
-    {
-        $model = $this->get_model();
-        foreach ($model->relation_settings() as $relation_name => $relation_obj) {
-            if ($relation_obj instanceof EE_Has_Many_Relation) {
-                foreach ($this->get_all_from_cache($relation_name) as $related_model_obj_in_cache) {
-                    $fk_to_this = $related_model_obj_in_cache->get_model()->get_foreign_key_to(
-                        $model->get_this_model_name()
-                    );
-                    $related_model_obj_in_cache->set($fk_to_this->get_name(), $this->ID());
-                    if ($related_model_obj_in_cache->ID()) {
-                        $related_model_obj_in_cache->save();
-                    }
-                }
-            }
-        }
-    }
-
-
-    /**
-     * Saves this model object and its NEW cached relations to the database.
-     * (Meaning, for now, IT DOES NOT WORK if the cached items already exist in the DB.
-     * In order for that to work, we would need to mark model objects as dirty/clean...
-     * because otherwise, there's a potential for infinite looping of saving
-     * Saves the cached related model objects, and ensures the relation between them
-     * and this object and properly setup
-     *
-     * @return int ID of new model object on save; 0 on failure+
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function save_new_cached_related_model_objs()
-    {
-        // make sure this has been saved
-        if (! $this->ID()) {
-            $id = $this->save();
-        } else {
-            $id = $this->ID();
-        }
-        // now save all the NEW cached model objects  (ie they don't exist in the DB)
-        foreach ($this->get_model()->relation_settings() as $relation_name => $relationObj) {
-            if ($this->_model_relations[ $relation_name ]) {
-                // is this a relation where we should expect just ONE related object (ie, EE_Belongs_To_relation)
-                // or MANY related objects (ie, EE_HABTM_Relation or EE_Has_Many_Relation)?
-                /* @var $related_model_obj EE_Base_Class */
-                if ($relationObj instanceof EE_Belongs_To_Relation) {
-                    // add a relation to that relation type (which saves the appropriate thing in the process)
-                    // but ONLY if it DOES NOT exist in the DB
-                    $related_model_obj = $this->_model_relations[ $relation_name ];
-                    // if( ! $related_model_obj->ID()){
-                    $this->_add_relation_to($related_model_obj, $relation_name);
-                    $related_model_obj->save_new_cached_related_model_objs();
-                    // }
-                } else {
-                    foreach ($this->_model_relations[ $relation_name ] as $related_model_obj) {
-                        // add a relation to that relation type (which saves the appropriate thing in the process)
-                        // but ONLY if it DOES NOT exist in the DB
-                        // if( ! $related_model_obj->ID()){
-                        $this->_add_relation_to($related_model_obj, $relation_name);
-                        $related_model_obj->save_new_cached_related_model_objs();
-                        // }
-                    }
-                }
-            }
-        }
-        return $id;
-    }
-
-
-    /**
-     * for getting a model while instantiated.
-     *
-     * @return EEM_Base | EEM_CPT_Base
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_model()
-    {
-        if (! $this->_model) {
-            $modelName    = self::_get_model_classname(get_class($this));
-            $this->_model = self::_get_model_instance_with_name($modelName, $this->_timezone);
-        } else {
-            $this->_model->set_timezone($this->_timezone);
-        }
-        return $this->_model;
-    }
-
-
-    /**
-     * @param $props_n_values
-     * @param $classname
-     * @return mixed bool|EE_Base_Class|EEM_CPT_Base
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected static function _get_object_from_entity_mapper($props_n_values, $classname)
-    {
-        // TODO: will not work for Term_Relationships because they have no PK!
-        $primary_id_ref = self::_get_primary_key_name($classname);
-        if (
-            array_key_exists($primary_id_ref, $props_n_values)
-            && ! empty($props_n_values[ $primary_id_ref ])
-        ) {
-            $id = $props_n_values[ $primary_id_ref ];
-            return self::_get_model($classname)->get_from_entity_map($id);
-        }
-        return false;
-    }
-
-
-    /**
-     * This is called by child static "new_instance" method and we'll check to see if there is an existing db entry for
-     * the primary key (if present in incoming values). If there is a key in the incoming array that matches the
-     * primary key for the model AND it is not null, then we check the db. If there's a an object we return it.  If not
-     * we return false.
-     *
-     * @param array  $props_n_values    incoming array of properties and their values
-     * @param string $classname         the classname of the child class
-     * @param null   $timezone
-     * @param array  $date_formats      incoming date_formats in an array where the first value is the
-     *                                  date_format and the second value is the time format
-     * @return mixed (EE_Base_Class|bool)
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    protected static function _check_for_object($props_n_values, $classname, $timezone = '', $date_formats = [])
-    {
-        $existing = null;
-        $model    = self::_get_model($classname, $timezone);
-        if ($model->has_primary_key_field()) {
-            $primary_id_ref = self::_get_primary_key_name($classname);
-            if (
-                array_key_exists($primary_id_ref, $props_n_values)
-                && ! empty($props_n_values[ $primary_id_ref ])
-            ) {
-                $existing = $model->get_one_by_ID(
-                    $props_n_values[ $primary_id_ref ]
-                );
-            }
-        } elseif ($model->has_all_combined_primary_key_fields($props_n_values)) {
-            // no primary key on this model, but there's still a matching item in the DB
-            $existing = self::_get_model($classname, $timezone)->get_one_by_ID(
-                self::_get_model($classname, $timezone)
-                    ->get_index_primary_key_string($props_n_values)
-            );
-        }
-        if ($existing) {
-            // set date formats if present before setting values
-            if (! empty($date_formats) && is_array($date_formats)) {
-                $existing->set_date_format($date_formats[0]);
-                $existing->set_time_format($date_formats[1]);
-            } else {
-                // set default formats for date and time
-                $existing->set_date_format(get_option('date_format'));
-                $existing->set_time_format(get_option('time_format'));
-            }
-            foreach ($props_n_values as $property => $field_value) {
-                $existing->set($property, $field_value);
-            }
-            return $existing;
-        }
-        return false;
-    }
-
-
-    /**
-     * Gets the EEM_*_Model for this class
-     *
-     * @access public now, as this is more convenient
-     * @param      $classname
-     * @param null $timezone
-     * @return EEM_Base
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    protected static function _get_model($classname, $timezone = '')
-    {
-        // find model for this class
-        if (! $classname) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        'What were you thinking calling _get_model(%s)?? You need to specify the class name',
-                        'event_espresso'
-                    ),
-                    $classname
-                )
-            );
-        }
-        $modelName = self::_get_model_classname($classname);
-        return self::_get_model_instance_with_name($modelName, $timezone);
-    }
-
-
-    /**
-     * Gets the model instance (eg instance of EEM_Attendee) given its classname (eg EE_Attendee)
-     *
-     * @param string $model_classname
-     * @param null   $timezone
-     * @return EEM_Base
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    protected static function _get_model_instance_with_name($model_classname, $timezone = '')
-    {
-        $model_classname = str_replace('EEM_', '', $model_classname);
-        $model           = EE_Registry::instance()->load_model($model_classname);
-        $model->set_timezone($timezone);
-        return $model;
-    }
-
-
-    /**
-     * If a model name is provided (eg Registration), gets the model classname for that model.
-     * Also works if a model class's classname is provided (eg EE_Registration).
-     *
-     * @param string|null $model_name
-     * @return string like EEM_Attendee
-     */
-    private static function _get_model_classname($model_name = '')
-    {
-        return strpos((string) $model_name, 'EE_') === 0
-            ? str_replace('EE_', 'EEM_', $model_name)
-            : 'EEM_' . $model_name;
-    }
-
-
-    /**
-     * returns the name of the primary key attribute
-     *
-     * @param null $classname
-     * @return string
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    protected static function _get_primary_key_name($classname = null)
-    {
-        if (! $classname) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__('What were you thinking calling _get_primary_key_name(%s)', 'event_espresso'),
-                    $classname
-                )
-            );
-        }
-        return self::_get_model($classname)->get_primary_key_field()->get_name();
-    }
-
-
-    /**
-     * Gets the value of the primary key.
-     * If the object hasn't yet been saved, it should be whatever the model field's default was
-     * (eg, if this were the EE_Event class, look at the primary key field on EEM_Event and see what its default value
-     * is. Usually defaults for integer primary keys are 0; string primary keys are usually NULL).
-     *
-     * @return mixed, if the primary key is of type INT it'll be an int. Otherwise it could be a string
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function ID()
-    {
-        $model = $this->get_model();
-        // now that we know the name of the variable, use a variable variable to get its value and return its
-        if ($model->has_primary_key_field()) {
-            return $this->_fields[ $model->primary_key_name() ];
-        }
-        return $model->get_index_primary_key_string($this->_fields);
-    }
-
-
-    /**
-     * @param EE_Base_Class|int|string $otherModelObjectOrID
-     * @param string                   $relation_name
-     * @return bool
-     * @throws EE_Error
-     * @throws ReflectionException
-     * @since   5.0.0.p
-     */
-    public function hasRelation($otherModelObjectOrID, string $relation_name): bool
-    {
-        $other_model = self::_get_model_instance_with_name(
-            self::_get_model_classname($relation_name),
-            $this->_timezone
-        );
-        $primary_key = $other_model->primary_key_name();
-        /** @var EE_Base_Class $otherModelObject */
-        $otherModelObject = $other_model->ensure_is_obj($otherModelObjectOrID, $relation_name);
-        return $this->count_related($relation_name, [[$primary_key => $otherModelObject->ID()]]) > 0;
-    }
-
-
-    /**
-     * Adds a relationship to the specified EE_Base_Class object, given the relationship's name. Eg, if the current
-     * model is related to a group of events, the $relation_name should be 'Event', and should be a key in the EE
-     * Model's $_model_relations array. If this model object doesn't exist in the DB, just caches the related thing
-     *
-     * @param mixed  $otherObjectModelObjectOrID       EE_Base_Class or the ID of the other object
-     * @param string $relation_name                    eg 'Events','Question',etc.
-     *                                                 an attendee to a group, you also want to specify which role they
-     *                                                 will have in that group. So you would use this parameter to
-     *                                                 specify array('role-column-name'=>'role-id')
-     * @param array  $extra_join_model_fields_n_values You can optionally include an array of key=>value pairs that
-     *                                                 allow you to further constrict the relation to being added.
-     *                                                 However, keep in mind that the columns (keys) given must match a
-     *                                                 column on the JOIN table and currently only the HABTM models
-     *                                                 accept these additional conditions.  Also remember that if an
-     *                                                 exact match isn't found for these extra cols/val pairs, then a
-     *                                                 NEW row is created in the join table.
-     * @param null   $cache_id
-     * @return EE_Base_Class the object the relation was added to
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function _add_relation_to(
-        $otherObjectModelObjectOrID,
-        $relation_name,
-        $extra_join_model_fields_n_values = [],
-        $cache_id = null
-    ) {
-        $model = $this->get_model();
-        // if this thing exists in the DB, save the relation to the DB
-        if ($this->ID()) {
-            $otherObject = $model->add_relationship_to(
-                $this,
-                $otherObjectModelObjectOrID,
-                $relation_name,
-                $extra_join_model_fields_n_values
-            );
-            // clear cache so future get_many_related and get_first_related() return new results.
-            $this->clear_cache($relation_name, $otherObject, true);
-            if ($otherObject instanceof EE_Base_Class) {
-                $otherObject->clear_cache($model->get_this_model_name(), $this);
-            }
-        } else {
-            // this thing doesn't exist in the DB,  so just cache it
-            if (! $otherObjectModelObjectOrID instanceof EE_Base_Class) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            'Before a model object is saved to the database, calls to _add_relation_to must be passed an actual object, not just an ID. You provided %s as the model object to a %s',
-                            'event_espresso'
-                        ),
-                        $otherObjectModelObjectOrID,
-                        get_class($this)
-                    )
-                );
-            }
-            $otherObject = $otherObjectModelObjectOrID;
-            $this->cache($relation_name, $otherObjectModelObjectOrID, $cache_id);
-        }
-        if ($otherObject instanceof EE_Base_Class) {
-            // fix the reciprocal relation too
-            if ($otherObject->ID()) {
-                // its saved so assumed relations exist in the DB, so we can just
-                // clear the cache so future queries use the updated info in the DB
-                $otherObject->clear_cache(
-                    $model->get_this_model_name(),
-                    null,
-                    true
-                );
-            } else {
-                // it's not saved, so it caches relations like this
-                $otherObject->cache($model->get_this_model_name(), $this);
-            }
-        }
-        return $otherObject;
-    }
-
-
-    /**
-     * Removes a relationship to the specified EE_Base_Class object, given the relationships' name. Eg, if the current
-     * model is related to a group of events, the $relation_name should be 'Events', and should be a key in the EE
-     * Model's $_model_relations array. If this model object doesn't exist in the DB, just removes the related thing
-     * from the cache
-     *
-     * @param mixed  $otherObjectModelObjectOrID
-     *                EE_Base_Class or the ID of the other object, OR an array key into the cache if this isn't saved
-     *                to the DB yet
-     * @param string $relation_name
-     * @param array  $where_query
-     *                You can optionally include an array of key=>value pairs that allow you to further constrict the
-     *                relation to being added. However, keep in mind that the columns (keys) given must match a column
-     *                on the JOIN table and currently only the HABTM models accept these additional conditions. Also
-     *                remember that if an exact match isn't found for these extra cols/val pairs, then no row is
-     *                deleted.
-     * @return EE_Base_Class the relation was removed from
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function _remove_relation_to($otherObjectModelObjectOrID, $relation_name, $where_query = [])
-    {
-        if ($this->ID()) {
-            // if this exists in the DB, save the relation change to the DB too
-            $otherObject = $this->get_model()->remove_relationship_to(
-                $this,
-                $otherObjectModelObjectOrID,
-                $relation_name,
-                $where_query
-            );
-            $this->clear_cache(
-                $relation_name,
-                $otherObject
-            );
-        } else {
-            // this doesn't exist in the DB, just remove it from the cache
-            $otherObject = $this->clear_cache(
-                $relation_name,
-                $otherObjectModelObjectOrID
-            );
-        }
-        if ($otherObject instanceof EE_Base_Class) {
-            $otherObject->clear_cache(
-                $this->get_model()->get_this_model_name(),
-                $this
-            );
-        }
-        return $otherObject;
-    }
-
-
-    /**
-     * Removes ALL the related things for the $relation_name.
-     *
-     * @param string $relation_name
-     * @param array  $where_query_params @see
-     *                                   https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
-     * @return EE_Base_Class
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function _remove_relations($relation_name, $where_query_params = [])
-    {
-        if ($this->ID()) {
-            // if this exists in the DB, save the relation change to the DB too
-            $otherObjects = $this->get_model()->remove_relations(
-                $this,
-                $relation_name,
-                $where_query_params
-            );
-            $this->clear_cache(
-                $relation_name,
-                null,
-                true
-            );
-        } else {
-            // this doesn't exist in the DB, just remove it from the cache
-            $otherObjects = $this->clear_cache(
-                $relation_name,
-                null,
-                true
-            );
-        }
-        if (is_array($otherObjects)) {
-            foreach ($otherObjects as $otherObject) {
-                $otherObject->clear_cache(
-                    $this->get_model()->get_this_model_name(),
-                    $this
-                );
-            }
-        }
-        return $otherObjects;
-    }
-
-
-    /**
-     * Gets all the related model objects of the specified type. Eg, if the current class if
-     * EE_Event, you could call $this->get_many_related('Registration') to get an array of all the
-     * EE_Registration objects which related to this event. Note: by default, we remove the "default query params"
-     * because we want to get even deleted items etc.
-     *
-     * @param string      $relation_name key in the model's _model_relations array
-     * @param array|null  $query_params  @see
-     *                              https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
-     * @return EE_Base_Class[]     Results not necessarily indexed by IDs, because some results might not have primary
-     *                              keys or might not be saved yet. Consider using EEM_Base::get_IDs() on these
-     *                              results if you want IDs
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_many_related($relation_name, $query_params = [])
-    {
-        if ($this->ID()) {
-            // this exists in the DB, so get the related things from either the cache or the DB
-            // if there are query parameters, forget about caching the related model objects.
-            if ($query_params) {
-                $related_model_objects = $this->get_model()->get_all_related(
-                    $this,
-                    $relation_name,
-                    $query_params
-                );
-            } else {
-                // did we already cache the result of this query?
-                $cached_results = $this->get_all_from_cache($relation_name);
-                if (! $cached_results) {
-                    $related_model_objects = $this->get_model()->get_all_related(
-                        $this,
-                        $relation_name,
-                        $query_params
-                    );
-                    // if no query parameters were passed, then we got all the related model objects
-                    // for that relation. We can cache them then.
-                    foreach ($related_model_objects as $related_model_object) {
-                        $this->cache($relation_name, $related_model_object);
-                    }
-                } else {
-                    $related_model_objects = $cached_results;
-                }
-            }
-        } else {
-            // this doesn't exist in the DB, so just get the related things from the cache
-            $related_model_objects = $this->get_all_from_cache($relation_name);
-        }
-        return $related_model_objects;
-    }
-
-
-    /**
-     * Instead of getting the related model objects, simply counts them. Ignores default_where_conditions by default,
-     * unless otherwise specified in the $query_params
-     *
-     * @param string $relation_name  model_name like 'Event', or 'Registration'
-     * @param array  $query_params   @see
-     *                               https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @param string $field_to_count name of field to count by. By default, uses primary key
-     * @param bool   $distinct       if we want to only count the distinct values for the column then you can trigger
-     *                               that by the setting $distinct to TRUE;
-     * @return int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function count_related($relation_name, $query_params = [], $field_to_count = null, $distinct = false)
-    {
-        return $this->get_model()->count_related(
-            $this,
-            $relation_name,
-            $query_params,
-            $field_to_count,
-            $distinct
-        );
-    }
-
-
-    /**
-     * Instead of getting the related model objects, simply sums up the values of the specified field.
-     * Note: ignores default_where_conditions by default, unless otherwise specified in the $query_params
-     *
-     * @param string $relation_name model_name like 'Event', or 'Registration'
-     * @param array  $query_params  @see
-     *                              https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @param string $field_to_sum  name of field to count by.
-     *                              By default, uses primary key
-     *                              (which doesn't make much sense, so you should probably change it)
-     * @return int
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function sum_related($relation_name, $query_params = [], $field_to_sum = null)
-    {
-        return $this->get_model()->sum_related(
-            $this,
-            $relation_name,
-            $query_params,
-            $field_to_sum
-        );
-    }
-
-
-    /**
-     * Gets the first (ie, one) related model object of the specified type.
-     *
-     * @param string $relation_name key in the model's _model_relations array
-     * @param array  $query_params  @see
-     *                              https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return EE_Base_Class|null (not an array, a single object)
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function get_first_related(string $relation_name, array $query_params = []): ?EE_Base_Class
-    {
-        $model = $this->get_model();
-        if ($this->ID()) {// this exists in the DB, get from the cache OR the DB
-            // if they've provided some query parameters, don't bother trying to cache the result
-            // also make sure we're not caching the result of get_first_related
-            // on a relation which should have an array of objects (because the cache might have an array of objects)
-            if (
-                $query_params
-                || ! $model->related_settings_for($relation_name) instanceof EE_Belongs_To_Relation
-            ) {
-                $related_model_object = $model->get_first_related(
-                    $this,
-                    $relation_name,
-                    $query_params
-                );
-            } else {
-                // first, check if we've already cached the result of this query
-                $cached_result = $this->get_one_from_cache($relation_name);
-                if (! $cached_result) {
-                    $related_model_object = $model->get_first_related(
-                        $this,
-                        $relation_name,
-                        $query_params
-                    );
-                    $this->cache($relation_name, $related_model_object);
-                } else {
-                    $related_model_object = $cached_result;
-                }
-            }
-        } else {
-            $related_model_object = null;
-            // this doesn't exist in the Db,
-            // but maybe the relation is of type belongs to, and so the related thing might
-            if ($model->related_settings_for($relation_name) instanceof EE_Belongs_To_Relation) {
-                $related_model_object = $model->get_first_related(
-                    $this,
-                    $relation_name,
-                    $query_params
-                );
-            }
-            // this doesn't exist in the DB and apparently the thing it belongs to doesn't either,
-            // just get what's cached on this object
-            if (! $related_model_object) {
-                $related_model_object = $this->get_one_from_cache($relation_name);
-            }
-        }
-        return $related_model_object;
-    }
-
-
-    /**
-     * Does a delete on all related objects of type $relation_name and removes
-     * the current model object's relation to them. If they can't be deleted (because
-     * of blocking related model objects) does nothing. If the related model objects are
-     * soft-deletable, they will be soft-deleted regardless of related blocking model objects.
-     * If this model object doesn't exist yet in the DB, just removes its related things
-     *
-     * @param string $relation_name
-     * @param array  $query_params @see
-     *                             https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return int how many deleted
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function delete_related($relation_name, $query_params = [])
-    {
-        if ($this->ID()) {
-            $count = $this->get_model()->delete_related(
-                $this,
-                $relation_name,
-                $query_params
-            );
-        } else {
-            $count = count($this->get_all_from_cache($relation_name));
-            $this->clear_cache($relation_name, null, true);
-        }
-        return $count;
-    }
-
-
-    /**
-     * Does a hard delete (ie, removes the DB row) on all related objects of type $relation_name and removes
-     * the current model object's relation to them. If they can't be deleted (because
-     * of blocking related model objects) just does a soft delete on it instead, if possible.
-     * If the related thing isn't a soft-deletable model object, this function is identical
-     * to delete_related(). If this model object doesn't exist in the DB, just remove its related things
-     *
-     * @param string $relation_name
-     * @param array  $query_params @see
-     *                             https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
-     * @return int how many deleted (including those soft deleted)
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function delete_related_permanently($relation_name, $query_params = [])
-    {
-        $count = $this->ID()
-            ? $this->get_model()->delete_related_permanently(
-                $this,
-                $relation_name,
-                $query_params
-            )
-            : count($this->get_all_from_cache($relation_name));
-
-        $this->clear_cache($relation_name, null, true);
-        return $count;
-    }
-
-
-    /**
-     * is_set
-     * Just a simple utility function children can use for checking if property exists
-     *
-     * @access  public
-     * @param string $field_name property to check
-     * @return bool                              TRUE if existing,FALSE if not.
-     */
-    public function is_set($field_name)
-    {
-        return isset($this->_fields[ $field_name ]);
-    }
-
-
-    /**
-     * Just a simple utility function children can use for checking if property (or properties) exists and throwing an
-     * EE_Error exception if they don't
-     *
-     * @param mixed (string|array) $properties properties to check
-     * @return bool                              TRUE if existing, throw EE_Error if not.
-     * @throws EE_Error
-     */
-    protected function _property_exists($properties)
-    {
-        foreach ((array) $properties as $property_name) {
-            // first make sure this property exists
-            if (! $this->_fields[ $property_name ]) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            'Trying to retrieve a non-existent property (%s).  Double check the spelling please',
-                            'event_espresso'
-                        ),
-                        $property_name
-                    )
-                );
-            }
-        }
-        return true;
-    }
-
-
-    /**
-     * This simply returns an array of model fields for this object
-     *
-     * @return array
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function model_field_array()
-    {
-        $fields     = $this->get_model()->field_settings(false);
-        $properties = [];
-        // remove prepended underscore
-        foreach ($fields as $field_name => $settings) {
-            $properties[ $field_name ] = $this->get($field_name);
-        }
-        return $properties;
-    }
-
-
-    /**
-     * Very handy general function to allow for plugins to extend any child of EE_Base_Class.
-     * If a method is called on a child of EE_Base_Class that doesn't exist, this function is called
-     * (http://www.garfieldtech.com/blog/php-magic-call) and passed the method's name and arguments.
-     * Instead of requiring a plugin to extend the EE_Base_Class
-     * (which works fine is there's only 1 plugin, but when will that happen?)
-     * they can add a hook onto 'filters_hook_espresso__{className}__{methodName}'
-     * (eg, filters_hook_espresso__EE_Answer__my_great_function)
-     * and accepts 2 arguments: the object on which the function was called,
-     * and an array of the original arguments passed to the function.
-     * Whatever their callback function returns will be returned by this function.
-     * Example: in functions.php (or in a plugin):
-     *      add_filter('FHEE__EE_Answer__my_callback','my_callback',10,3);
-     *      function my_callback($previousReturnValue,EE_Base_Class $object,$argsArray){
-     *          $returnString= "you called my_callback! and passed args:".implode(",",$argsArray);
-     *          return $previousReturnValue.$returnString;
-     *      }
-     * require('EE_Answer.class.php');
-     * echo EE_Answer::new_instance(['REG_ID' => 2,'QST_ID' => 3,'ANS_value' => The answer is 42'])
-     *      ->my_callback('monkeys',100);
-     * // will output "you called my_callback! and passed args:monkeys,100"
-     *
-     * @param string $methodName name of method which was called on a child of EE_Base_Class, but which
-     * @param array  $args       array of original arguments passed to the function
-     * @return mixed whatever the plugin which calls add_filter decides
-     * @throws EE_Error
-     */
-    public function __call($methodName, $args)
-    {
-        $className = get_class($this);
-        $tagName   = "FHEE__{$className}__{$methodName}";
-        if (! has_filter($tagName)) {
-            throw new EE_Error(
-                sprintf(
-                    esc_html__(
-                        "Method %s on class %s does not exist! You can create one with the following code in functions.php or in a plugin: add_filter('%s','my_callback',10,3);function my_callback(\$previousReturnValue,EE_Base_Class \$object, \$argsArray){/*function body*/return \$whatever;}",
-                        'event_espresso'
-                    ),
-                    $methodName,
-                    $className,
-                    $tagName
-                )
-            );
-        }
-        return apply_filters($tagName, null, $this, $args);
-    }
-
-
-    /**
-     * Similar to insert_post_meta, adds a record in the Extra_Meta model's table with the given key and value.
-     * A $previous_value can be specified in case there are many meta rows with the same key
-     *
-     * @param string $meta_key
-     * @param mixed  $meta_value
-     * @param mixed  $previous_value
-     * @return bool|int # of records updated (or BOOLEAN if we actually ended up inserting the extra meta row)
-     *                  NOTE: if the values haven't changed, returns 0
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function update_extra_meta(string $meta_key, $meta_value, $previous_value = null)
-    {
-        $query_params = [
-            [
-                'EXM_key'  => $meta_key,
-                'OBJ_ID'   => $this->ID(),
-                'EXM_type' => $this->get_model()->get_this_model_name(),
-            ],
-        ];
-        if ($previous_value !== null) {
-            $query_params[0]['EXM_value'] = $meta_value;
-        }
-        $existing_rows_like_that = EEM_Extra_Meta::instance()->get_all($query_params);
-        if (! $existing_rows_like_that) {
-            return $this->add_extra_meta($meta_key, $meta_value);
-        }
-        foreach ($existing_rows_like_that as $existing_row) {
-            $existing_row->save(['EXM_value' => $meta_value]);
-        }
-        return count($existing_rows_like_that);
-    }
-
-
-    /**
-     * Adds a new extra meta record. If $unique is set to TRUE, we'll first double-check
-     * no other extra meta for this model object have the same key. Returns TRUE if the
-     * extra meta row was entered, false if not
-     *
-     * @param string $meta_key
-     * @param mixed  $meta_value
-     * @param bool   $unique
-     * @return bool
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function add_extra_meta(string $meta_key, $meta_value, bool $unique = false): bool
-    {
-        if ($unique) {
-            $existing_extra_meta = EEM_Extra_Meta::instance()->get_one(
-                [
-                    [
-                        'EXM_key'  => $meta_key,
-                        'OBJ_ID'   => $this->ID(),
-                        'EXM_type' => $this->get_model()->get_this_model_name(),
-                    ],
-                ]
-            );
-            if ($existing_extra_meta) {
-                return false;
-            }
-        }
-        $new_extra_meta = EE_Extra_Meta::new_instance(
-            [
-                'EXM_key'   => $meta_key,
-                'EXM_value' => $meta_value,
-                'OBJ_ID'    => $this->ID(),
-                'EXM_type'  => $this->get_model()->get_this_model_name(),
-            ]
-        );
-        $new_extra_meta->save();
-        return true;
-    }
-
-
-    /**
-     * Deletes all the extra meta rows for this record as specified by key. If $meta_value
-     * is specified, only deletes extra meta records with that value.
-     *
-     * @param string $meta_key
-     * @param mixed  $meta_value
-     * @return int|bool number of extra meta rows deleted
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function delete_extra_meta(string $meta_key, $meta_value = null)
-    {
-        $query_params = [
-            [
-                'EXM_key'  => $meta_key,
-                'OBJ_ID'   => $this->ID(),
-                'EXM_type' => $this->get_model()->get_this_model_name(),
-            ],
-        ];
-        if ($meta_value !== null) {
-            $query_params[0]['EXM_value'] = $meta_value;
-        }
-        return EEM_Extra_Meta::instance()->delete($query_params);
-    }
-
-
-    /**
-     * Gets the extra meta with the given meta key. If you specify "single" we just return 1, otherwise
-     * an array of everything found. Requires that this model actually have a relation of type EE_Has_Many_Any_Relation.
-     * You can specify $default is case you haven't found the extra meta
-     *
-     * @param string     $meta_key
-     * @param bool       $single
-     * @param mixed      $default if we don't find anything, what should we return?
-     * @param array|null $extra_where
-     * @return mixed single value if $single; array if ! $single
-     * @throws ReflectionException
-     * @throws EE_Error
-     */
-    public function get_extra_meta(string $meta_key, bool $single = false, $default = null, ?array $extra_where = [])
-    {
-        $query_params = [$extra_where + ['EXM_key' => $meta_key]];
-        if ($single) {
-            $result = $this->get_first_related('Extra_Meta', $query_params);
-            if ($result instanceof EE_Extra_Meta) {
-                return $result->value();
-            }
-        } else {
-            $results = $this->get_many_related('Extra_Meta', $query_params);
-            if ($results) {
-                $values = [];
-                foreach ($results as $result) {
-                    if ($result instanceof EE_Extra_Meta) {
-                        $values[ $result->ID() ] = $result->value();
-                    }
-                }
-                return $values;
-            }
-        }
-        // if nothing discovered yet return default.
-        return apply_filters(
-            'FHEE__EE_Base_Class__get_extra_meta__default_value',
-            $default,
-            $meta_key,
-            $single,
-            $this
-        );
-    }
-
-
-    /**
-     * Returns a simple array of all the extra meta associated with this model object.
-     * If $one_of_each_key is true (Default), it will be an array of simple key-value pairs, keys being the
-     * extra meta's key, and teh value being its value. However, if there are duplicate extra meta rows with
-     * the same key, only one will be used. (eg array('foo'=>'bar','monkey'=>123))
-     * If $one_of_each_key is false, it will return an array with the top-level keys being
-     * the extra meta keys, but their values are also arrays, which have the extra-meta's ID as their sub-key, and
-     * finally the extra meta's value as each sub-value. (eg
-     * array('foo'=>array(1=>'bar',2=>'bill'),'monkey'=>array(3=>123)))
-     *
-     * @param bool $one_of_each_key
-     * @return array
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function all_extra_meta_array(bool $one_of_each_key = true): array
-    {
-        $return_array = [];
-        if ($one_of_each_key) {
-            $extra_meta_objs = $this->get_many_related(
-                'Extra_Meta',
-                ['group_by' => 'EXM_key']
-            );
-            foreach ($extra_meta_objs as $extra_meta_obj) {
-                if ($extra_meta_obj instanceof EE_Extra_Meta) {
-                    $return_array[ $extra_meta_obj->key() ] = $extra_meta_obj->value();
-                }
-            }
-        } else {
-            $extra_meta_objs = $this->get_many_related('Extra_Meta');
-            foreach ($extra_meta_objs as $extra_meta_obj) {
-                if ($extra_meta_obj instanceof EE_Extra_Meta) {
-                    if (! isset($return_array[ $extra_meta_obj->key() ])) {
-                        $return_array[ $extra_meta_obj->key() ] = [];
-                    }
-                    $return_array[ $extra_meta_obj->key() ][ $extra_meta_obj->ID() ] = $extra_meta_obj->value();
-                }
-            }
-        }
-        return $return_array;
-    }
-
-
-    /**
-     * Gets a pretty nice displayable nice for this model object. Often overridden
-     *
-     * @return string
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function name()
-    {
-        // find a field that's not a text field
-        $field_we_can_use = $this->get_model()->get_a_field_of_type('EE_Text_Field_Base');
-        if ($field_we_can_use) {
-            return $this->get($field_we_can_use->get_name());
-        }
-        $first_few_properties = $this->model_field_array();
-        $first_few_properties = array_slice($first_few_properties, 0, 3);
-        $name_parts           = [];
-        foreach ($first_few_properties as $name => $value) {
-            $name_parts[] = "$name:$value";
-        }
-        return implode(',', $name_parts);
-    }
-
-
-    /**
-     * in_entity_map
-     * Checks if this model object has been proven to already be in the entity map
-     *
-     * @return boolean
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function in_entity_map()
-    {
-        // well, if we looked, did we find it in the entity map?
-        return $this->ID() && $this->get_model()->get_from_entity_map($this->ID()) === $this;
-    }
-
-
-    /**
-     * refresh_from_db
-     * Makes sure the fields and values on this model object are in-sync with what's in the database.
-     *
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error if this model object isn't in the entity mapper (because then you should
-     * just use what's in the entity mapper and refresh it) and WP_DEBUG is TRUE
-     */
-    public function refresh_from_db()
-    {
-        if ($this->ID() && $this->in_entity_map()) {
-            $this->get_model()->refresh_entity_map_from_db($this->ID());
-        } else {
-            // if it doesn't have ID, you shouldn't be asking to refresh it from teh database (because its not in the database)
-            // if it has an ID but it's not in the map, and you're asking me to refresh it
-            // that's kinda dangerous. You should just use what's in the entity map, or add this to the entity map if there's
-            // absolutely nothing in it for this ID
-            if (WP_DEBUG) {
-                throw new EE_Error(
-                    sprintf(
-                        esc_html__(
-                            'Trying to refresh a model object with ID "%1$s" that\'s not in the entity map? First off: you should put it in the entity map by calling %2$s. Second off, if you want what\'s in the database right now, you should just call %3$s yourself and discard this model object.',
-                            'event_espresso'
-                        ),
-                        $this->ID(),
-                        get_class($this->get_model()) . '::instance()->add_to_entity_map()',
-                        get_class($this->get_model()) . '::instance()->refresh_entity_map()'
-                    )
-                );
-            }
-        }
-    }
-
-
-    /**
-     * Change $fields' values to $new_value_sql (which is a string of raw SQL)
-     *
-     * @param EE_Model_Field_Base[] $fields
-     * @param string                $new_value_sql
-     *          example: 'column_name=123',
-     *          or 'column_name=column_name+1',
-     *          or 'column_name= CASE
-     *          WHEN (`column_name` + `other_column` + 5) <= `yet_another_column`
-     *          THEN `column_name` + 5
-     *          ELSE `column_name`
-     *          END'
-     *          Also updates $field on this model object with the latest value from the database.
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @since 4.9.80.p
-     */
-    protected function updateFieldsInDB($fields, $new_value_sql)
-    {
-        // First make sure this model object actually exists in the DB. It would be silly to try to update it in the DB
-        // if it wasn't even there to start off.
-        if (! $this->ID()) {
-            $this->save();
-        }
-        global $wpdb;
-        if (empty($fields)) {
-            throw new InvalidArgumentException(
-                esc_html__(
-                    'EE_Base_Class::updateFieldsInDB was passed an empty array of fields.',
-                    'event_espresso'
-                )
-            );
-        }
-        $first_field = reset($fields);
-        $table_alias = $first_field->get_table_alias();
-        foreach ($fields as $field) {
-            if ($table_alias !== $field->get_table_alias()) {
-                throw new InvalidArgumentException(
-                    sprintf(
-                        esc_html__(
-                        // @codingStandardsIgnoreStart
-                            'EE_Base_Class::updateFieldsInDB was passed fields for different tables ("%1$s" and "%2$s"), which is not supported. Instead, please call the method multiple times.',
-                            // @codingStandardsIgnoreEnd
-                            'event_espresso'
-                        ),
-                        $table_alias,
-                        $field->get_table_alias()
-                    )
-                );
-            }
-        }
-        // Ok the fields are now known to all be for the same table. Proceed with creating the SQL to update it.
-        $table_obj      = $this->get_model()->get_table_obj_by_alias($table_alias);
-        $table_pk_value = $this->ID();
-        $table_name     = $table_obj->get_table_name();
-        if ($table_obj instanceof EE_Secondary_Table) {
-            $table_pk_field_name = $table_obj->get_fk_on_table();
-        } else {
-            $table_pk_field_name = $table_obj->get_pk_column();
-        }
-
-        $query  =
-            "UPDATE `{$table_name}`
+	/**
+	 * @var EEM_Base|null
+	 */
+	protected $_model = null;
+
+	/**
+	 * This is an array of the original properties and values provided during construction
+	 * of this model object. (keys are model field names, values are their values).
+	 * This list is important to remember so that when we are merging data from the db, we know
+	 * which values to override and which to not override.
+	 */
+	protected ?array $_props_n_values_provided_in_constructor = null;
+
+	/**
+	 * Timezone
+	 * This gets set by the "set_timezone()" method so that we know what timezone incoming strings|timestamps are in.
+	 * This can also be used before a get to set what timezone you want strings coming out of the object to be in.  NOT
+	 * all EE_Base_Class child classes use this property but any that use a EE_Datetime_Field data type will have
+	 * access to it.
+	 */
+	protected string $_timezone = '';
+
+	/**
+	 * date format
+	 * pattern or format for displaying dates
+	 */
+	protected string $_dt_frmt = '';
+
+	/**
+	 * time format
+	 * pattern or format for displaying time
+	 */
+	protected string $_tm_frmt = '';
+
+	/**
+	 * This property is for holding a cached array of object properties indexed by property name as the key.
+	 * The purpose of this is for setting a cache on properties that may have calculated values after a
+	 * prepare_for_get.  That way the cache can be checked first and the calculated property returned instead of having
+	 * to recalculate. Used by _set_cached_property() and _get_cached_property() methods.
+	 */
+	protected array $_cached_properties = [];
+
+	/**
+	 * An array containing keys of the related model, and values are either an array of related mode objects or a
+	 * single
+	 * related model object. see the model's _model_relations. The keys should match those specified. And if the
+	 * relation is of type EE_Belongs_To (or one of its children), then there should only be ONE related model object,
+	 * all others have an array)
+	 */
+	protected array $_model_relations = [];
+
+	/**
+	 * Array where keys are field names (see the model's _fields property) and values are their values. To see what
+	 * their types should be, look at what that field object returns on its prepare_for_get and prepare_for_set methods)
+	 */
+	protected array $_fields = [];
+
+	/**
+	 * indicating whether or not this model object is intended to ever be saved
+	 * For example, we might create model objects intended to only be used for the duration
+	 * of this request and to be thrown away, and if they were accidentally saved
+	 * it would be a bug.
+	 */
+	protected bool $_allow_persist = true;
+
+	/**
+	 * indicating whether or not this model object's properties have changed since construction
+	 */
+	protected bool $_has_changes = false;
+
+	/**
+	 * This is a cache of results from custom selections done on a query that constructs this entity. The only purpose
+	 * for these values is for retrieval of the results, they are not further queryable and they are not persisted to
+	 * the db.  They also do not automatically update if there are any changes to the data that produced their results.
+	 * The format is a simple array of field_alias => field_value.  So for instance if a custom select was something
+	 * like,  "Select COUNT(Registration.REG_ID) as Registration_Count ...", then the resulting value will be in this
+	 * array as:
+	 * array(
+	 *  'Registration_Count' => 24
+	 * );
+	 * Note: if the custom select configuration for the query included a data type, the value will be in the data type
+	 * provided for the query (@see EventEspresso\core\domain\values\model\CustomSelects::__construct phpdocs for more
+	 * info)
+	 */
+	protected array $custom_selection_results = [];
+
+
+	/**
+	 * basic constructor for Event Espresso classes, performs any necessary initialization, and verifies it's children
+	 * play nice
+	 *
+	 * @param array   $fieldValues                             where each key is a field (ie, array key in the 2nd
+	 *                                                         layer of the model's _fields array, (eg, EVT_ID,
+	 *                                                         TXN_amount, QST_name, etc) and values are their values
+	 * @param boolean $bydb                                    a flag for setting if the class is instantiated by the
+	 *                                                         corresponding db model or not.
+	 * @param string  $timezone                                indicate what timezone you want any datetime fields to
+	 *                                                         be in when instantiating a EE_Base_Class object.
+	 * @param array   $date_formats                            An array of date formats to set on construct where first
+	 *                                                         value is the date_format and second value is the time
+	 *                                                         format.
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	protected function __construct($fieldValues = [], $bydb = false, $timezone = '', $date_formats = [])
+	{
+		$className = get_class($this);
+		do_action("AHEE__{$className}__construct", $this, $fieldValues);
+		$model        = $this->get_model();
+		$model_fields = $model->field_settings();
+		// ensure $fieldValues is an array
+		$fieldValues = is_array($fieldValues) ? $fieldValues : [$fieldValues];
+		// verify client code has not passed any invalid field names
+		foreach ($fieldValues as $field_name => $field_value) {
+			if (! isset($model_fields[ $field_name ])) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							'Invalid field (%s) passed to constructor of %s. Allowed fields are :%s',
+							'event_espresso'
+						),
+						$field_name,
+						get_class($this),
+						implode(', ', array_keys($model_fields))
+					)
+				);
+			}
+		}
+
+		$date_format     = null;
+		$time_format     = null;
+		$this->_timezone = EEH_DTT_Helper::get_valid_timezone_string($timezone);
+		if (! empty($date_formats) && is_array($date_formats)) {
+			[$date_format, $time_format] = $date_formats;
+		}
+		$this->set_date_format($date_format);
+		$this->set_time_format($time_format);
+		// if db model is instantiating
+		foreach ($model_fields as $fieldName => $field) {
+			if ($bydb) {
+				// client code has indicated these field values are from the database
+				$this->set_from_db(
+					$fieldName,
+					$fieldValues[ $fieldName ] ?? null
+				);
+			} else {
+				// we're constructing a brand new instance of the model object.
+				// Generally, this means we'll need to do more field validation
+				$this->set(
+					$fieldName,
+					$fieldValues[ $fieldName ] ?? null,
+					true
+				);
+			}
+		}
+		// remember what values were passed to this constructor
+		$this->_props_n_values_provided_in_constructor = $fieldValues;
+		// remember in entity mapper
+		if (! $bydb && $model->has_primary_key_field() && $this->ID()) {
+			$model->add_to_entity_map($this);
+		}
+		// setup all the relations
+		foreach ($model->relation_settings() as $relation_name => $relation_obj) {
+			if ($relation_obj instanceof EE_Belongs_To_Relation) {
+				$this->_model_relations[ $relation_name ] = null;
+			} else {
+				$this->_model_relations[ $relation_name ] = [];
+			}
+		}
+		/**
+		 * Action done at the end of each model object construction
+		 *
+		 * @param EE_Base_Class $this the model object just created
+		 */
+		do_action('AHEE__EE_Base_Class__construct__finished', $this);
+	}
+
+
+	/**
+	 * Gets whether or not this model object is allowed to persist/be saved to the database.
+	 *
+	 * @return boolean
+	 */
+	public function allow_persist()
+	{
+		return $this->_allow_persist;
+	}
+
+
+	/**
+	 * Sets whether or not this model object should be allowed to be saved to the DB.
+	 * Normally once this is set to FALSE you wouldn't set it back to TRUE, unless
+	 * you got new information that somehow made you change your mind.
+	 *
+	 * @param boolean $allow_persist
+	 * @return boolean
+	 */
+	public function set_allow_persist($allow_persist)
+	{
+		return $this->_allow_persist = $allow_persist;
+	}
+
+
+	/**
+	 * Gets the field's original value when this object was constructed during this request.
+	 * This can be helpful when determining if a model object has changed or not
+	 *
+	 * @param string $field_name
+	 * @return mixed|null
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_original($field_name)
+	{
+		if (
+			isset($this->_props_n_values_provided_in_constructor[ $field_name ])
+			&& $field_settings = $this->get_model()->field_settings_for($field_name)
+		) {
+			return $field_settings->prepare_for_get($this->_props_n_values_provided_in_constructor[ $field_name ]);
+		}
+		return null;
+	}
+
+
+	/**
+	 * @param EE_Base_Class $obj
+	 * @return string
+	 */
+	public function get_class($obj)
+	{
+		return get_class($obj);
+	}
+
+
+	/**
+	 * Overrides parent because parent expects old models.
+	 * This also doesn't do any validation, and won't work for serialized arrays
+	 *
+	 * @param string $field_name
+	 * @param mixed  $field_value
+	 * @param bool   $use_default
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws Exception
+	 */
+	public function set(string $field_name, $field_value, bool $use_default = false)
+	{
+		// if not using default and nothing has changed, and object has already been setup (has ID),
+		// then don't do anything
+		if (
+			! $use_default
+			&& $this->_fields[ $field_name ] === $field_value
+			&& $this->ID()
+		) {
+			return;
+		}
+		$model              = $this->get_model();
+		$this->_has_changes = true;
+		$field_obj          = $model->field_settings_for($field_name);
+		if (! $field_obj instanceof EE_Model_Field_Base) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'A valid EE_Model_Field_Base could not be found for the given field name: %s',
+						'event_espresso'
+					),
+					$field_name
+				)
+			);
+		}
+		// if ( method_exists( $field_obj, 'set_timezone' )) {
+		if ($field_obj instanceof EE_Datetime_Field) {
+			$field_obj->set_timezone($this->_timezone);
+			$field_obj->set_date_format($this->_dt_frmt);
+			$field_obj->set_time_format($this->_tm_frmt);
+		}
+
+		// should the value be null?
+		$value = $field_value === null && ($use_default || ! $field_obj->is_nullable())
+			? $field_obj->get_default_value()
+			: $field_value;
+
+		$this->_fields[ $field_name ] = $field_obj->prepare_for_set($value);
+
+		// if we're not in the constructor...
+		// now check if what we set was a primary key
+		if (
+			// note: props_n_values_provided_in_constructor is only set at the END of the constructor
+			$this->_props_n_values_provided_in_constructor
+			&& $field_value
+			&& $field_name === $model->primary_key_name()
+		) {
+			// if so, we want all this object's fields to be filled either with
+			// what we've explicitly set on this model
+			// or what we have in the db
+			// echo "setting primary key!";
+			$fields_on_model = self::_get_model(get_class($this))->field_settings();
+			$obj_in_db       = self::_get_model(get_class($this))->get_one_by_ID($field_value);
+			foreach ($fields_on_model as $field_obj) {
+				if (
+					! array_key_exists($field_obj->get_name(), $this->_props_n_values_provided_in_constructor)
+					&& $field_obj->get_name() !== $field_name
+				) {
+					$this->set($field_obj->get_name(), $obj_in_db->get($field_obj->get_name()));
+				}
+			}
+			// oh this model object has an ID? well make sure its in the entity mapper
+			$model->add_to_entity_map($this);
+		}
+		// let's unset any cache for this field_name from the $_cached_properties property.
+		$this->_clear_cached_property($field_name);
+	}
+
+
+	/**
+	 * Overrides parent because parent expects old models.
+	 * This also doesn't do any validation, and won't work for serialized arrays
+	 *
+	 * @param string $field_name
+	 * @param mixed  $field_value_from_db
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function set_from_db(string $field_name, $field_value_from_db)
+	{
+		$field_obj = $this->get_model()->field_settings_for($field_name);
+		if ($field_obj instanceof EE_Model_Field_Base) {
+			// you would think the DB has no NULLs for non-null label fields right? wrong!
+			// eg, a CPT model object could have an entry in the posts table, but no
+			// entry in the meta table. Meaning that all its columns in the meta table
+			// are null! yikes! so when we find one like that, use defaults for its meta columns
+			if ($field_value_from_db === null) {
+				if ($field_obj->is_nullable()) {
+					// if the field allows nulls, then let it be null
+					$field_value = null;
+				} else {
+					$field_value = $field_obj->get_default_value();
+				}
+			} else {
+				$field_value = $field_obj->prepare_for_set_from_db($field_value_from_db);
+			}
+			$this->_fields[ $field_name ] = $field_value;
+			$this->_clear_cached_property($field_name);
+		}
+	}
+
+
+	/**
+	 * Set custom select values for model.
+	 *
+	 * @param array $custom_select_values
+	 */
+	public function setCustomSelectsValues(array $custom_select_values)
+	{
+		$this->custom_selection_results = $custom_select_values;
+	}
+
+
+	/**
+	 * Returns the custom select value for the provided alias if its set.
+	 * If not set, returns null.
+	 *
+	 * @param string $alias
+	 * @return string|int|float|null
+	 */
+	public function getCustomSelect($alias)
+	{
+		return $this->custom_selection_results[ $alias ] ?? null;
+	}
+
+
+	/**
+	 * This sets the field value on the db column if it exists for the given $column_name or
+	 * saves it to EE_Extra_Meta if the given $column_name does not match a db column.
+	 *
+	 * @param string $field_name  Must be the exact column name.
+	 * @param mixed  $field_value The value to set.
+	 * @return int|bool @see EE_Base_Class::update_extra_meta() for return docs.
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @see EE_message::get_column_value for related documentation on the necessity of this method.
+	 */
+	public function set_field_or_extra_meta($field_name, $field_value)
+	{
+		if ($this->get_model()->has_field($field_name)) {
+			$this->set($field_name, $field_value);
+			return true;
+		}
+		// ensure this object is saved first so that extra meta can be properly related.
+		$this->save();
+		return $this->update_extra_meta($field_name, $field_value);
+	}
+
+
+	/**
+	 * This retrieves the value of the db column set on this class or if that's not present
+	 * it will attempt to retrieve from extra_meta if found.
+	 * Example Usage:
+	 * Via EE_Message child class:
+	 * Due to the dynamic nature of the EE_messages system, EE_messengers will always have a "to",
+	 * "from", "subject", and "content" field (as represented in the EE_Message schema), however they may
+	 * also have additional main fields specific to the messenger.  The system accommodates those extra
+	 * fields through the EE_Extra_Meta table.  This method allows for EE_messengers to retrieve the
+	 * value for those extra fields dynamically via the EE_message object.
+	 *
+	 * @param string $field_name expecting the fully qualified field name.
+	 * @return mixed|null  value for the field if found.  null if not found.
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_field_or_extra_meta($field_name)
+	{
+		if ($this->get_model()->has_field($field_name)) {
+			$column_value = $this->get($field_name);
+		} else {
+			// This isn't a column in the main table, let's see if it is in the extra meta.
+			$column_value = $this->get_extra_meta($field_name, true, null);
+		}
+		return $column_value;
+	}
+
+
+	/**
+	 * See $_timezone property for description of what the timezone property is for.  This SETS the timezone internally
+	 * for being able to reference what timezone we are running conversions on when converting TO the internal timezone
+	 * (UTC Unix Timestamp) for the object OR when converting FROM the internal timezone (UTC Unix Timestamp). This is
+	 * available to all child classes that may be using the EE_Datetime_Field for a field data type.
+	 *
+	 * @access public
+	 * @param string $timezone A valid timezone string as described by @link http://www.php.net/manual/en/timezones.php
+	 * @return void
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @throws Exception
+	 */
+	public function set_timezone($timezone = '')
+	{
+		$this->_timezone = EEH_DTT_Helper::get_valid_timezone_string($timezone);
+		// make sure we clear all cached properties because they won't be relevant now
+		$this->_clear_cached_properties();
+		// make sure we update field settings and the date for all EE_Datetime_Fields
+		$model_fields = $this->get_model()->field_settings(false);
+		foreach ($model_fields as $field_name => $field_obj) {
+			if ($field_obj instanceof EE_Datetime_Field) {
+				$field_obj->set_timezone($this->_timezone);
+				if (isset($this->_fields[ $field_name ]) && $this->_fields[ $field_name ] instanceof DateTime) {
+					EEH_DTT_Helper::setTimezone($this->_fields[ $field_name ], new DateTimeZone($this->_timezone));
+				}
+			}
+		}
+	}
+
+
+	/**
+	 * This just returns whatever is set for the current timezone.
+	 *
+	 * @access public
+	 * @return string timezone string
+	 */
+	public function get_timezone()
+	{
+		return $this->_timezone;
+	}
+
+
+	/**
+	 * This sets the internal date format to what is sent in to be used as the new default for the class
+	 * internally instead of wp set date format options
+	 *
+	 * @param string|null $format should be a format recognizable by PHP date() functions.
+	 * @since 4.6
+	 */
+	public function set_date_format(?string $format)
+	{
+		$this->_dt_frmt = new DateFormat($format);
+		// clear cached_properties because they won't be relevant now.
+		$this->_clear_cached_properties();
+	}
+
+
+	/**
+	 * This sets the internal time format string to what is sent in to be used as the new default for the
+	 * class internally instead of wp set time format options.
+	 *
+	 * @param string|null $format should be a format recognizable by PHP date() functions.
+	 * @since 4.6
+	 */
+	public function set_time_format(?string $format)
+	{
+		$this->_tm_frmt = new TimeFormat($format);
+		// clear cached_properties because they won't be relevant now.
+		$this->_clear_cached_properties();
+	}
+
+
+	/**
+	 * This returns the current internal set format for the date and time formats.
+	 *
+	 * @param bool $full           if true (default), then return the full format.  Otherwise will return an array
+	 *                             where the first value is the date format and the second value is the time format.
+	 * @return string|array
+	 */
+	public function get_format($full = true)
+	{
+		return $full ? $this->_dt_frmt . ' ' . $this->_tm_frmt : [$this->_dt_frmt, $this->_tm_frmt];
+	}
+
+
+	/**
+	 * cache
+	 * stores the passed model object on the current model object.
+	 * In certain circumstances, we can use this cached model object instead of querying for another one entirely.
+	 *
+	 * @param string        $relation_name   one of the keys in the _model_relations array on the model. Eg
+	 *                                       'Registration' associated with this model object
+	 * @param EE_Base_Class $object_to_cache that has a relation to this model object. (Eg, if this is a Transaction,
+	 *                                       that could be a payment or a registration)
+	 * @param null          $cache_id        a string or number that will be used as the key for any Belongs_To_Many
+	 *                                       items which will be stored in an array on this object
+	 * @return mixed    index into cache, or just TRUE if the relation is of type Belongs_To (because there's only one
+	 *                                       related thing, no array)
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function cache($relation_name = '', $object_to_cache = null, $cache_id = null)
+	{
+		// its entirely possible that there IS no related object yet in which case there is nothing to cache.
+		if (! $object_to_cache instanceof EE_Base_Class) {
+			return false;
+		}
+		// also get "how" the object is related, or throw an error
+		if (! $relationship_to_model = $this->get_model()->related_settings_for($relation_name)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__('There is no relationship to %s on a %s. Cannot cache it', 'event_espresso'),
+					$relation_name,
+					get_class($this)
+				)
+			);
+		}
+		// how many things are related ?
+		if ($relationship_to_model instanceof EE_Belongs_To_Relation) {
+			// if it's a "belongs to" relationship, then there's only one related model object
+			// eg, if this is a registration, there's only 1 attendee for it
+			// so for these model objects just set it to be cached
+			$this->_model_relations[ $relation_name ] = $object_to_cache;
+			$return                                   = true;
+		} else {
+			// otherwise, this is the "many" side of a one to many relationship,
+			// so we'll add the object to the array of related objects for that type.
+			// eg: if this is an event, there are many registrations for that event,
+			// so we cache the registrations in an array
+			if (! is_array($this->_model_relations[ $relation_name ])) {
+				// if for some reason, the cached item is a model object,
+				// then stick that in the array, otherwise start with an empty array
+				$this->_model_relations[ $relation_name ] =
+					$this->_model_relations[ $relation_name ] instanceof EE_Base_Class
+						? [$this->_model_relations[ $relation_name ]]
+						: [];
+			}
+			// first check for a cache_id which is normally empty
+			if (! empty($cache_id)) {
+				// if the cache_id exists, then it means we are purposely trying to cache this
+				// with a known key that can then be used to retrieve the object later on
+				$this->_model_relations[ $relation_name ][ $cache_id ] = $object_to_cache;
+				$return                                                = $cache_id;
+			} elseif ($object_to_cache->ID()) {
+				// OR the cached object originally came from the db, so let's just use it's PK for an ID
+				$this->_model_relations[ $relation_name ][ $object_to_cache->ID() ] = $object_to_cache;
+				$return                                                             = $object_to_cache->ID();
+			} else {
+				// OR it's a new object with no ID, so just throw it in the array with an auto-incremented ID
+				$this->_model_relations[ $relation_name ][] = $object_to_cache;
+				// move the internal pointer to the end of the array
+				end($this->_model_relations[ $relation_name ]);
+				// and grab the key so that we can return it
+				$return = key($this->_model_relations[ $relation_name ]);
+			}
+		}
+		return $return;
+	}
+
+
+	/**
+	 * For adding an item to the cached_properties property.
+	 *
+	 * @access protected
+	 * @param string      $fieldname the property item the corresponding value is for.
+	 * @param mixed       $value     The value we are caching.
+	 * @param string|null $cache_type
+	 * @return void
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _set_cached_property($fieldname, $value, $cache_type = null)
+	{
+		// first make sure this property exists
+		$this->get_model()->field_settings_for($fieldname);
+		$cache_type = empty($cache_type) ? 'standard' : $cache_type;
+
+		$this->_cached_properties[ $fieldname ][ $cache_type ] = $value;
+	}
+
+
+	/**
+	 * This returns the value cached property if it exists OR the actual property value if the cache doesn't exist.
+	 * This also SETS the cache if we return the actual property!
+	 *
+	 * @param string $fieldname        the name of the property we're trying to retrieve
+	 * @param bool   $pretty
+	 * @param string $extra_cache_ref  This allows the user to specify an extra cache ref for the given property
+	 *                                 (in cases where the same property may be used for different outputs
+	 *                                 - i.e. datetime, money etc.)
+	 *                                 It can also accept certain pre-defined "schema" strings
+	 *                                 to define how to output the property.
+	 *                                 see the field's prepare_for_pretty_echoing for what strings can be used
+	 * @return mixed                   whatever the value for the property is we're retrieving
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _get_cached_property($fieldname, $pretty = false, $extra_cache_ref = null)
+	{
+		// verify the field exists
+		$model = $this->get_model();
+		$model->field_settings_for($fieldname);
+		$cache_type = $pretty ? 'pretty' : 'standard';
+		$cache_type .= ! empty($extra_cache_ref) ? '_' . $extra_cache_ref : '';
+		if (isset($this->_cached_properties[ $fieldname ][ $cache_type ])) {
+			return $this->_cached_properties[ $fieldname ][ $cache_type ];
+		}
+		$value = $this->_get_fresh_property($fieldname, $pretty, $extra_cache_ref);
+		$this->_set_cached_property($fieldname, $value, $cache_type);
+		return $value;
+	}
+
+
+	/**
+	 * If the cache didn't fetch the needed item, this fetches it.
+	 *
+	 * @param string $fieldname
+	 * @param bool   $pretty
+	 * @param string $extra_cache_ref
+	 * @return mixed
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	protected function _get_fresh_property($fieldname, $pretty = false, $extra_cache_ref = null)
+	{
+		$field_obj = $this->get_model()->field_settings_for($fieldname);
+		// If this is an EE_Datetime_Field we need to make sure timezone, formats, and output are correct
+		if ($field_obj instanceof EE_Datetime_Field) {
+			$this->_prepare_datetime_field($field_obj, $pretty, $extra_cache_ref);
+		}
+		if (! isset($this->_fields[ $fieldname ])) {
+			$this->_fields[ $fieldname ] = null;
+		}
+		return $pretty
+			? $field_obj->prepare_for_pretty_echoing($this->_fields[ $fieldname ], $extra_cache_ref)
+			: $field_obj->prepare_for_get($this->_fields[ $fieldname ]);
+	}
+
+
+	/**
+	 * set timezone, formats, and output for EE_Datetime_Field objects
+	 *
+	 * @param EE_Datetime_Field $datetime_field
+	 * @param bool              $pretty
+	 * @param null              $date_or_time
+	 * @return void
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 */
+	protected function _prepare_datetime_field(
+		EE_Datetime_Field $datetime_field,
+		$pretty = false,
+		$date_or_time = null
+	) {
+		$datetime_field->set_timezone($this->_timezone);
+		$datetime_field->set_date_format($this->_dt_frmt, $pretty);
+		$datetime_field->set_time_format($this->_tm_frmt, $pretty);
+		// set the output returned
+		switch ($date_or_time) {
+			case 'D':
+				$datetime_field->set_date_time_output('date');
+				break;
+			case 'T':
+				$datetime_field->set_date_time_output('time');
+				break;
+			default:
+				$datetime_field->set_date_time_output();
+		}
+	}
+
+
+	/**
+	 * This just takes care of clearing out the cached_properties
+	 *
+	 * @return void
+	 */
+	protected function _clear_cached_properties()
+	{
+		$this->_cached_properties = [];
+	}
+
+
+	/**
+	 * This just clears out ONE property if it exists in the cache
+	 *
+	 * @param string $property_name the property to remove if it exists (from the _cached_properties array)
+	 * @return void
+	 */
+	protected function _clear_cached_property($property_name)
+	{
+		if (isset($this->_cached_properties[ $property_name ])) {
+			unset($this->_cached_properties[ $property_name ]);
+		}
+	}
+
+
+	/**
+	 * Ensures that this related thing is a model object.
+	 *
+	 * @param mixed  $object_or_id EE_base_Class/int/string either a related model object, or its ID
+	 * @param string $model_name   name of the related thing, eg 'Attendee',
+	 * @return EE_Base_Class
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function ensure_related_thing_is_model_obj($object_or_id, $model_name)
+	{
+		$other_model_instance = self::_get_model_instance_with_name(
+			self::_get_model_classname($model_name),
+			$this->_timezone
+		);
+		return $other_model_instance->ensure_is_obj($object_or_id);
+	}
+
+
+	/**
+	 * Forgets the cached model of the given relation Name. So the next time we request it,
+	 * we will fetch it again from the database. (Handy if you know it's changed somehow).
+	 * If a specific object is supplied, and the relationship to it is either a HasMany or HABTM,
+	 * then only remove that one object from our cached array. Otherwise, clear the entire list
+	 *
+	 * @param string $relation_name                        one of the keys in the _model_relations array on the model.
+	 *                                                     Eg 'Registration'
+	 * @param mixed  $object_to_remove_or_index_into_array or an index into the array of cached things, or NULL
+	 *                                                     if you intend to use $clear_all = TRUE, or the relation only
+	 *                                                     has 1 object anyways (ie, it's a BelongsToRelation)
+	 * @param bool   $clear_all                            This flags clearing the entire cache relation property if
+	 *                                                     this is HasMany or HABTM.
+	 * @return EE_Base_Class | boolean from which was cleared from the cache, or true if we requested to remove a
+	 *                                                     relation from all
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function clear_cache($relation_name, $object_to_remove_or_index_into_array = null, $clear_all = false)
+	{
+		$relationship_to_model = $this->get_model()->related_settings_for($relation_name);
+		$index_in_cache        = '';
+		if (! $relationship_to_model) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__('There is no relationship to %s on a %s. Cannot clear that cache', 'event_espresso'),
+					$relation_name,
+					get_class($this)
+				)
+			);
+		}
+		if ($clear_all) {
+			$obj_removed                              = true;
+			$this->_model_relations[ $relation_name ] = null;
+		} elseif ($relationship_to_model instanceof EE_Belongs_To_Relation) {
+			$obj_removed                              = $this->_model_relations[ $relation_name ];
+			$this->_model_relations[ $relation_name ] = null;
+		} else {
+			if (
+				$object_to_remove_or_index_into_array instanceof EE_Base_Class
+				&& $object_to_remove_or_index_into_array->ID()
+			) {
+				$index_in_cache = $object_to_remove_or_index_into_array->ID();
+				if (
+					is_array($this->_model_relations[ $relation_name ])
+					&& ! isset($this->_model_relations[ $relation_name ][ $index_in_cache ])
+				) {
+					$index_found_at = null;
+					// find this object in the array even though it has a different key
+					foreach ($this->_model_relations[ $relation_name ] as $index => $obj) {
+						/** @noinspection TypeUnsafeComparisonInspection */
+						if (
+							$obj instanceof EE_Base_Class
+							&& (
+								$obj == $object_to_remove_or_index_into_array
+								|| $obj->ID() === $object_to_remove_or_index_into_array->ID()
+							)
+						) {
+							$index_found_at = $index;
+							break;
+						}
+					}
+					if ($index_found_at) {
+						$index_in_cache = $index_found_at;
+					} else {
+						// it wasn't found. huh. well obviously it doesn't need to be removed from teh cache
+						// if it wasn't in it to begin with. So we're done
+						return $object_to_remove_or_index_into_array;
+					}
+				}
+			} elseif ($object_to_remove_or_index_into_array instanceof EE_Base_Class) {
+				// so they provided a model object, but it's not yet saved to the DB... so let's go hunting for it!
+				foreach ($this->get_all_from_cache($relation_name) as $index => $potentially_obj_we_want) {
+					/** @noinspection TypeUnsafeComparisonInspection */
+					if ($potentially_obj_we_want == $object_to_remove_or_index_into_array) {
+						$index_in_cache = $index;
+					}
+				}
+			} else {
+				$index_in_cache = $object_to_remove_or_index_into_array;
+			}
+			// supposedly we've found it. But it could just be that the client code
+			// provided a bad index/object
+			if (isset($this->_model_relations[ $relation_name ][ $index_in_cache ])) {
+				$obj_removed = $this->_model_relations[ $relation_name ][ $index_in_cache ];
+				unset($this->_model_relations[ $relation_name ][ $index_in_cache ]);
+			} else {
+				// that thing was never cached anyways.
+				$obj_removed = null;
+			}
+		}
+		return $obj_removed;
+	}
+
+
+	/**
+	 * update_cache_after_object_save
+	 * Allows a cached item to have it's cache ID (within the array of cached items) reset using the new ID it has
+	 * obtained after being saved to the db
+	 *
+	 * @param string        $relation_name      - the type of object that is cached
+	 * @param EE_Base_Class $newly_saved_object - the newly saved object to be re-cached
+	 * @param string        $current_cache_id   - the ID that was used when originally caching the object
+	 * @return boolean TRUE on success, FALSE on fail
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function update_cache_after_object_save(
+		$relation_name,
+		EE_Base_Class $newly_saved_object,
+		$current_cache_id = ''
+	) {
+		// verify that incoming object is of the correct type
+		$obj_class = 'EE_' . $relation_name;
+		if ($newly_saved_object instanceof $obj_class) {
+			/* @type EE_Base_Class $newly_saved_object */
+			// now get the type of relation
+			$relationship_to_model = $this->get_model()->related_settings_for($relation_name);
+			// if this is a 1:1 relationship
+			if ($relationship_to_model instanceof EE_Belongs_To_Relation) {
+				// then just replace the cached object with the newly saved object
+				$this->_model_relations[ $relation_name ] = $newly_saved_object;
+				return true;
+				// or if it's some kind of sordid feral polyamorous relationship...
+			}
+			if (
+				is_array($this->_model_relations[ $relation_name ])
+				&& isset($this->_model_relations[ $relation_name ][ $current_cache_id ])
+			) {
+				// then remove the current cached item
+				unset($this->_model_relations[ $relation_name ][ $current_cache_id ]);
+				// and cache the newly saved object using it's new ID
+				$this->_model_relations[ $relation_name ][ $newly_saved_object->ID() ] = $newly_saved_object;
+				return true;
+			}
+		}
+		return false;
+	}
+
+
+	/**
+	 * Fetches a single EE_Base_Class on that relation. (If the relation is of type
+	 * BelongsTo, it will only ever have 1 object. However, other relations could have an array of objects)
+	 *
+	 * @param string $relation_name
+	 * @return EE_Base_Class
+	 */
+	public function get_one_from_cache($relation_name)
+	{
+		$cached_array_or_object = $this->_model_relations[ $relation_name ] ?? null;
+		if (is_array($cached_array_or_object)) {
+			return array_shift($cached_array_or_object);
+		}
+		return $cached_array_or_object;
+	}
+
+
+	/**
+	 * Fetches a single EE_Base_Class on that relation. (If the relation is of type
+	 * BelongsTo, it will only ever have 1 object. However, other relations could have an array of objects)
+	 *
+	 * @param string $relation_name
+	 * @return EE_Base_Class[] NOT necessarily indexed by primary keys
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function get_all_from_cache($relation_name)
+	{
+		$objects = $this->_model_relations[ $relation_name ] ?? [];
+		// if the result is not an array, but exists, make it an array
+		$objects = is_array($objects)
+			? $objects
+			: [$objects];
+		// bugfix for https://events.codebasehq.com/projects/event-espresso/tickets/7143
+		// basically, if this model object was stored in the session, and these cached model objects
+		// already have IDs, let's make sure they're in their model's entity mapper
+		// otherwise we will have duplicates next time we call
+		// EE_Registry::instance()->load_model( $relation_name )->get_one_by_ID( $result->ID() );
+		$model = EE_Registry::instance()->load_model($relation_name);
+		foreach ($objects as $model_object) {
+			if ($model instanceof EEM_Base && $model_object instanceof EE_Base_Class) {
+				// ensure its in the map if it has an ID; otherwise it will be added to the map when its saved
+				if ($model_object->ID()) {
+					$model->add_to_entity_map($model_object);
+				}
+			} else {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							'Error retrieving related model objects. Either $1%s is not a model or $2%s is not a model object',
+							'event_espresso'
+						),
+						$relation_name,
+						gettype($model_object)
+					)
+				);
+			}
+		}
+		return $objects;
+	}
+
+
+	/**
+	 * Returns the next x number of EE_Base_Class objects in sequence from this object as found in the database
+	 * matching the given query conditions.
+	 *
+	 * @param null  $field_to_order_by  What field is being used as the reference point.
+	 * @param int   $limit              How many objects to return.
+	 * @param array $query_params       Any additional conditions on the query.
+	 * @param null  $columns_to_select  If left null, then an array of EE_Base_Class objects is returned, otherwise
+	 *                                  you can indicate just the columns you want returned
+	 * @return array|EE_Base_Class[]
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function next_x($field_to_order_by = null, $limit = 1, $query_params = [], $columns_to_select = null)
+	{
+		$model         = $this->get_model();
+		$field         = empty($field_to_order_by) && $model->has_primary_key_field()
+			? $model->get_primary_key_field()->get_name()
+			: $field_to_order_by;
+		$current_value = ! empty($field)
+			? $this->get($field)
+			: null;
+		if (empty($field) || empty($current_value)) {
+			return [];
+		}
+		return $model->next_x($current_value, $field, $limit, $query_params, $columns_to_select);
+	}
+
+
+	/**
+	 * Returns the previous x number of EE_Base_Class objects in sequence from this object as found in the database
+	 * matching the given query conditions.
+	 *
+	 * @param null  $field_to_order_by  What field is being used as the reference point.
+	 * @param int   $limit              How many objects to return.
+	 * @param array $query_params       Any additional conditions on the query.
+	 * @param null  $columns_to_select  If left null, then an array of EE_Base_Class objects is returned, otherwise
+	 *                                  you can indicate just the columns you want returned
+	 * @return array|EE_Base_Class[]
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function previous_x(
+		$field_to_order_by = null,
+		$limit = 1,
+		$query_params = [],
+		$columns_to_select = null
+	) {
+		$model         = $this->get_model();
+		$field         = empty($field_to_order_by) && $model->has_primary_key_field()
+			? $model->get_primary_key_field()->get_name()
+			: $field_to_order_by;
+		$current_value = ! empty($field) ? $this->get($field) : null;
+		if (empty($field) || empty($current_value)) {
+			return [];
+		}
+		return $model->previous_x($current_value, $field, $limit, $query_params, $columns_to_select);
+	}
+
+
+	/**
+	 * Returns the next EE_Base_Class object in sequence from this object as found in the database
+	 * matching the given query conditions.
+	 *
+	 * @param null  $field_to_order_by  What field is being used as the reference point.
+	 * @param array $query_params       Any additional conditions on the query.
+	 * @param null  $columns_to_select  If left null, then an array of EE_Base_Class objects is returned, otherwise
+	 *                                  you can indicate just the columns you want returned
+	 * @return array|EE_Base_Class
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function next($field_to_order_by = null, $query_params = [], $columns_to_select = null)
+	{
+		$model         = $this->get_model();
+		$field         = empty($field_to_order_by) && $model->has_primary_key_field()
+			? $model->get_primary_key_field()->get_name()
+			: $field_to_order_by;
+		$current_value = ! empty($field) ? $this->get($field) : null;
+		if (empty($field) || empty($current_value)) {
+			return [];
+		}
+		return $model->next($current_value, $field, $query_params, $columns_to_select);
+	}
+
+
+	/**
+	 * Returns the previous EE_Base_Class object in sequence from this object as found in the database
+	 * matching the given query conditions.
+	 *
+	 * @param null  $field_to_order_by  What field is being used as the reference point.
+	 * @param array $query_params       Any additional conditions on the query.
+	 * @param null  $columns_to_select  If left null, then an EE_Base_Class object is returned, otherwise
+	 *                                  you can indicate just the column you want returned
+	 * @return array|EE_Base_Class
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function previous($field_to_order_by = null, $query_params = [], $columns_to_select = null)
+	{
+		$model         = $this->get_model();
+		$field         = empty($field_to_order_by) && $model->has_primary_key_field()
+			? $model->get_primary_key_field()->get_name()
+			: $field_to_order_by;
+		$current_value = ! empty($field) ? $this->get($field) : null;
+		if (empty($field) || empty($current_value)) {
+			return [];
+		}
+		return $model->previous($current_value, $field, $query_params, $columns_to_select);
+	}
+
+
+	/**
+	 * verifies that the specified field is of the correct type
+	 *
+	 * @param string $field_name
+	 * @param string $extra_cache_ref This allows the user to specify an extra cache ref for the given property
+	 *                                (in cases where the same property may be used for different outputs
+	 *                                - i.e. datetime, money etc.)
+	 * @return mixed
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get($field_name, $extra_cache_ref = null)
+	{
+		return $this->_get_cached_property($field_name, false, $extra_cache_ref);
+	}
+
+
+	/**
+	 * This method simply returns the RAW unprocessed value for the given property in this class
+	 *
+	 * @param string $field_name A valid fieldname
+	 * @return mixed              Whatever the raw value stored on the property is.
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error if fieldSettings is misconfigured or the field doesn't exist.
+	 */
+	public function get_raw($field_name)
+	{
+		$field_settings = $this->get_model()->field_settings_for($field_name);
+		return $field_settings instanceof EE_Datetime_Field && $this->_fields[ $field_name ] instanceof DateTime
+			? $this->_fields[ $field_name ]->format('U')
+			: $this->_fields[ $field_name ];
+	}
+
+
+	/**
+	 * This is used to return the internal DateTime object used for a field that is a
+	 * EE_Datetime_Field.
+	 *
+	 * @param string $field_name               The field name retrieving the DateTime object.
+	 * @return mixed null | false | DateTime  If the requested field is NOT a EE_Datetime_Field then
+	 * @throws EE_Error an error is set and false returned.  If the field IS an
+	 *                                         EE_Datetime_Field and but the field value is null, then
+	 *                                         just null is returned (because that indicates that likely
+	 *                                         this field is nullable).
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 */
+	public function get_DateTime_object($field_name)
+	{
+		$field_settings = $this->get_model()->field_settings_for($field_name);
+		if (! $field_settings instanceof EE_Datetime_Field) {
+			EE_Error::add_error(
+				sprintf(
+					esc_html__(
+						'The field %s is not an EE_Datetime_Field field.  There is no DateTime object stored on this field type.',
+						'event_espresso'
+					),
+					$field_name
+				),
+				__FILE__,
+				__FUNCTION__,
+				__LINE__
+			);
+			return false;
+		}
+		return isset($this->_fields[ $field_name ]) && $this->_fields[ $field_name ] instanceof DateTime
+			? clone $this->_fields[ $field_name ]
+			: null;
+	}
+
+
+	/**
+	 * To be used in template to immediately echo out the value, and format it for output.
+	 * Eg, should call stripslashes and whatnot before echoing
+	 *
+	 * @param string $field_name      the name of the field as it appears in the DB
+	 * @param string $extra_cache_ref This allows the user to specify an extra cache ref for the given property
+	 *                                (in cases where the same property may be used for different outputs
+	 *                                - i.e. datetime, money etc.)
+	 * @return void
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e($field_name, $extra_cache_ref = null)
+	{
+		echo wp_kses($this->get_pretty($field_name, $extra_cache_ref), AllowedTags::getWithFormTags());
+	}
+
+
+	/**
+	 * Exactly like e(), echoes out the field, but sets its schema to 'form_input', so that it
+	 * can be easily used as the value of form input.
+	 *
+	 * @param string $field_name
+	 * @return void
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function f($field_name)
+	{
+		$this->e($field_name, 'form_input');
+	}
+
+
+	/**
+	 * Same as `f()` but just returns the value instead of echoing it
+	 *
+	 * @param string $field_name
+	 * @return string
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_f($field_name)
+	{
+		return (string) $this->get_pretty($field_name, 'form_input');
+	}
+
+
+	/**
+	 * Gets a pretty view of the field's value. $extra_cache_ref can specify different formats for this.
+	 * The $extra_cache_ref will be passed to the model field's prepare_for_pretty_echoing, so consult the field's class
+	 * to see what options are available.
+	 *
+	 * @param string $field_name
+	 * @param string $extra_cache_ref This allows the user to specify an extra cache ref for the given property
+	 *                                (in cases where the same property may be used for different outputs
+	 *                                - i.e. datetime, money etc.)
+	 * @return mixed
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_pretty($field_name, $extra_cache_ref = null)
+	{
+		return $this->_get_cached_property($field_name, true, $extra_cache_ref);
+	}
+
+
+	/**
+	 * This simply returns the datetime for the given field name
+	 * Note: this protected function is called by the wrapper get_date or get_time or get_datetime functions
+	 * (and the equivalent e_date, e_time, e_datetime).
+	 *
+	 * @access   protected
+	 * @param string      $field_name   Field on the instantiated EE_Base_Class child object
+	 * @param string|null $date_format  valid datetime format used for date
+	 *                                  (if '' then we just use the default on the field,
+	 *                                  if NULL we use the last-used format)
+	 * @param string|null $time_format  Same as above except this is for time format
+	 * @param string|null $date_or_time if NULL then both are returned, otherwise "D" = only date and "T" = only time.
+	 * @param bool|null   $echo         Whether the datetime is pretty echoing or just returned using vanilla get
+	 * @return string|bool|EE_Error string on success, FALSE on fail, or EE_Error Exception is thrown
+	 *                                  if field is not a valid dtt field, or void if echoing
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	protected function _get_datetime(
+		string $field_name,
+		?string $date_format = '',
+		?string $time_format = '',
+		?string $date_or_time = '',
+		?bool $echo = false
+	) {
+		// clear cached property
+		$this->_clear_cached_property($field_name);
+		// reset format properties because they are used in get()
+		$this->_dt_frmt = $date_format ?: $this->_dt_frmt;
+		$this->_tm_frmt = $time_format ?: $this->_tm_frmt;
+		if ($echo) {
+			$this->e($field_name, $date_or_time);
+			return '';
+		}
+		return $this->get($field_name, $date_or_time);
+	}
+
+
+	/**
+	 * below are wrapper functions for the various datetime outputs that can be obtained for JUST returning the date
+	 * portion of a datetime value. (note the only difference between get_ and e_ is one returns the value and the
+	 * other echoes the pretty value for dtt)
+	 *
+	 * @param string $field_name name of model object datetime field holding the value
+	 * @param string $format     format for the date returned (if NULL we use default in dt_frmt property)
+	 * @return string            datetime value formatted
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_date($field_name, $format = '')
+	{
+		return $this->_get_datetime($field_name, $format, null, 'D');
+	}
+
+
+	/**
+	 * @param        $field_name
+	 * @param string $format
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e_date($field_name, $format = '')
+	{
+		$this->_get_datetime($field_name, $format, null, 'D', true);
+	}
+
+
+	/**
+	 * below are wrapper functions for the various datetime outputs that can be obtained for JUST returning the time
+	 * portion of a datetime value. (note the only difference between get_ and e_ is one returns the value and the
+	 * other echoes the pretty value for dtt)
+	 *
+	 * @param string $field_name name of model object datetime field holding the value
+	 * @param string $format     format for the time returned ( if NULL we use default in tm_frmt property)
+	 * @return string             datetime value formatted
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_time($field_name, $format = '')
+	{
+		return $this->_get_datetime($field_name, null, $format, 'T');
+	}
+
+
+	/**
+	 * @param        $field_name
+	 * @param string $format
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e_time($field_name, $format = '')
+	{
+		$this->_get_datetime($field_name, null, $format, 'T', true);
+	}
+
+
+	/**
+	 * below are wrapper functions for the various datetime outputs that can be obtained for returning the date AND
+	 * time portion of a datetime value. (note the only difference between get_ and e_ is one returns the value and the
+	 * other echoes the pretty value for dtt)
+	 *
+	 * @param string $field_name  name of model object datetime field holding the value
+	 * @param string $date_format format for the date returned (if NULL we use default in dt_frmt property)
+	 * @param string $time_format format for the time returned (if NULL we use default in tm_frmt property)
+	 * @return string             datetime value formatted
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_datetime($field_name, $date_format = '', $time_format = '')
+	{
+		return $this->_get_datetime($field_name, $date_format, $time_format);
+	}
+
+
+	/**
+	 * @param string $field_name
+	 * @param string $date_format
+	 * @param string $time_format
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function e_datetime($field_name, $date_format = '', $time_format = '')
+	{
+		$this->_get_datetime($field_name, $date_format, $time_format, null, true);
+	}
+
+
+	/**
+	 * Get the i8ln value for a date using the WordPress @param string $field_name The EE_Datetime_Field reference for
+	 *                           the date being retrieved.
+	 *
+	 * @param string $format     PHP valid date/time string format.  If none is provided then the internal set format
+	 *                           on the object will be used.
+	 * @return string Date and time string in set locale or false if no field exists for the given
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 *                           field name.
+	 * @see date_i18n function.
+	 */
+	public function get_i18n_datetime(string $field_name, string $format = ''): string
+	{
+		$format = empty($format) ? $this->_dt_frmt . ' ' . $this->_tm_frmt : $format;
+		return date_i18n(
+			$format,
+			EEH_DTT_Helper::get_timestamp_with_offset(
+				$this->get_raw($field_name),
+				$this->_timezone
+			)
+		);
+	}
+
+
+	/**
+	 * This method validates whether the given field name is a valid field on the model object as well as it is of a
+	 * type EE_Datetime_Field.  On success there will be returned the field settings.  On fail an EE_Error exception is
+	 * thrown.
+	 *
+	 * @param string $field_name The field name being checked
+	 * @return EE_Datetime_Field
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	protected function _get_dtt_field_settings($field_name)
+	{
+		$field = $this->get_model()->field_settings_for($field_name);
+		// check if field is dtt
+		if ($field instanceof EE_Datetime_Field) {
+			return $field;
+		}
+		throw new EE_Error(
+			sprintf(
+				esc_html__(
+					'The field name "%s" has been requested for the EE_Base_Class datetime functions and it is not a valid EE_Datetime_Field.  Please check the spelling of the field and make sure it has been setup as a EE_Datetime_Field in the %s model constructor',
+					'event_espresso'
+				),
+				$field_name,
+				self::_get_model_classname(get_class($this))
+			)
+		);
+	}
+
+
+
+
+	/**
+	 * NOTE ABOUT BELOW:
+	 * These convenience date and time setters are for setting date and time independently.  In other words you might
+	 * want to change the time on a datetime_field but leave the date the same (or vice versa). IF on the other hand
+	 * you want to set both date and time at the same time, you can just use the models default set($fieldname,$value)
+	 * method and make sure you send the entire datetime value for setting.
+	 */
+	/**
+	 * sets the time on a datetime property
+	 *
+	 * @access protected
+	 * @param string|Datetime $time      a valid time string for php datetime functions (or DateTime object)
+	 * @param string          $fieldname the name of the field the time is being set on (must match a EE_Datetime_Field)
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _set_time_for($time, $fieldname)
+	{
+		$this->_set_date_time('T', $time, $fieldname);
+	}
+
+
+	/**
+	 * sets the date on a datetime property
+	 *
+	 * @access protected
+	 * @param string|DateTime $date      a valid date string for php datetime functions ( or DateTime object)
+	 * @param string          $fieldname the name of the field the date is being set on (must match a EE_Datetime_Field)
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _set_date_for($date, $fieldname)
+	{
+		$this->_set_date_time('D', $date, $fieldname);
+	}
+
+
+	/**
+	 * This takes care of setting a date or time independently on a given model object property. This method also
+	 * verifies that the given field_name matches a model object property and is for a EE_Datetime_Field field
+	 *
+	 * @access protected
+	 * @param string          $what           "T" for time, 'B' for both, 'D' for Date.
+	 * @param string|DateTime $datetime_value A valid Date or Time string (or DateTime object)
+	 * @param string          $field_name     the name of the field the date OR time is being set on (must match a
+	 *                                        EE_Datetime_Field property)
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _set_date_time(string $what, $datetime_value, string $field_name)
+	{
+		$field = $this->_get_dtt_field_settings($field_name);
+		$field->set_timezone($this->_timezone);
+		$field->set_date_format($this->_dt_frmt);
+		$field->set_time_format($this->_tm_frmt);
+		switch ($what) {
+			case 'T':
+				$this->_fields[ $field_name ] = $field->prepare_for_set_with_new_time(
+					$datetime_value,
+					$this->_fields[ $field_name ]
+				);
+				$this->_has_changes           = true;
+				break;
+			case 'D':
+				$this->_fields[ $field_name ] = $field->prepare_for_set_with_new_date(
+					$datetime_value,
+					$this->_fields[ $field_name ]
+				);
+				$this->_has_changes           = true;
+				break;
+			case 'B':
+				$this->_fields[ $field_name ] = $field->prepare_for_set($datetime_value);
+				$this->_has_changes           = true;
+				break;
+		}
+		$this->_clear_cached_property($field_name);
+	}
+
+
+	/**
+	 * This will return a timestamp for the website timezone but ONLY when the current website timezone is different
+	 * than the timezone set for the website. NOTE, this currently only works well with methods that return values.  If
+	 * you use it with methods that echo values the $_timestamp property may not get reset to its original value and
+	 * that could lead to some unexpected results!
+	 *
+	 * @access public
+	 * @param string $field_name               This is the name of the field on the object that contains the date/time
+	 *                                         value being returned.
+	 * @param string $callback                 must match a valid method in this class (defaults to get_datetime)
+	 * @param mixed (array|string) $args       This is the arguments that will be passed to the callback.
+	 * @param string $prepend                  You can include something to prepend on the timestamp
+	 * @param string $append                   You can include something to append on the timestamp
+	 * @return string timestamp
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function display_in_my_timezone(
+		$field_name,
+		$callback = 'get_datetime',
+		$args = null,
+		$prepend = '',
+		$append = ''
+	) {
+		$timezone = EEH_DTT_Helper::get_timezone();
+		if ($timezone === $this->_timezone) {
+			return '';
+		}
+		$original_timezone = $this->_timezone;
+		$this->set_timezone($timezone);
+		$fn   = (array) $field_name;
+		$args = array_merge($fn, (array) $args);
+		if (! method_exists($this, $callback)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'The method named "%s" given as the callback param in "display_in_my_timezone" does not exist.  Please check your spelling',
+						'event_espresso'
+					),
+					$callback
+				)
+			);
+		}
+		$args   = (array) $args;
+		$return = $prepend . call_user_func_array([$this, $callback], $args) . $append;
+		$this->set_timezone($original_timezone);
+		return $return;
+	}
+
+
+	/**
+	 * Deletes this model object.
+	 * This calls the `EE_Base_Class::_delete` method.  Child classes wishing to change default behaviour should
+	 * override
+	 * `EE_Base_Class::_delete` NOT this class.
+	 *
+	 * @return boolean | int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function delete()
+	{
+		/**
+		 * Called just before the `EE_Base_Class::_delete` method call.
+		 * Note:
+		 * `EE_Base_Class::_delete` might be overridden by child classes so any client code hooking into these actions
+		 * should be aware that `_delete` may not always result in a permanent delete.
+		 * For example, `EE_Soft_Delete_Base_Class::_delete`
+		 * soft deletes (trash) the object and does not permanently delete it.
+		 *
+		 * @param EE_Base_Class $model_object about to be 'deleted'
+		 */
+		do_action('AHEE__EE_Base_Class__delete__before', $this);
+		$result = $this->_delete();
+		/**
+		 * Called just after the `EE_Base_Class::_delete` method call.
+		 * Note:
+		 * `EE_Base_Class::_delete` might be overridden by child classes so any client code hooking into these actions
+		 * should be aware that `_delete` may not always result in a permanent delete.
+		 * For example `EE_Soft_Base_Class::_delete`
+		 * soft deletes (trash) the object and does not permanently delete it.
+		 *
+		 * @param EE_Base_Class $model_object that was just 'deleted'
+		 * @param boolean       $result
+		 */
+		do_action('AHEE__EE_Base_Class__delete__end', $this, $result);
+		return $result;
+	}
+
+
+	/**
+	 * Calls the specific delete method for the instantiated class.
+	 * This method is called by the public `EE_Base_Class::delete` method.  Any child classes desiring to override
+	 * default functionality for "delete" (which is to call `permanently_delete`) should override this method NOT
+	 * `EE_Base_Class::delete`
+	 *
+	 * @return bool|int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _delete()
+	{
+		return $this->delete_permanently();
+	}
+
+
+	/**
+	 * Deletes this model object permanently from db
+	 * (but keep in mind related models may block the delete and return an error)
+	 *
+	 * @return bool | int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function delete_permanently()
+	{
+		/**
+		 * Called just before HARD deleting a model object
+		 *
+		 * @param EE_Base_Class $model_object about to be 'deleted'
+		 */
+		do_action('AHEE__EE_Base_Class__delete_permanently__before', $this);
+		$model  = $this->get_model();
+		$result = $model->delete_permanently_by_ID($this->ID());
+		$this->refresh_cache_of_related_objects();
+		/**
+		 * Called just after HARD deleting a model object
+		 *
+		 * @param EE_Base_Class $model_object that was just 'deleted'
+		 * @param boolean       $result
+		 */
+		do_action('AHEE__EE_Base_Class__delete_permanently__end', $this, $result);
+		return $result;
+	}
+
+
+	/**
+	 * When this model object is deleted, it may still be cached on related model objects. This clears the cache of
+	 * related model objects
+	 *
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function refresh_cache_of_related_objects()
+	{
+		$model = $this->get_model();
+		foreach ($model->relation_settings() as $relation_name => $relation_obj) {
+			if (! empty($this->_model_relations[ $relation_name ])) {
+				$related_objects = $this->_model_relations[ $relation_name ];
+				if ($relation_obj instanceof EE_Belongs_To_Relation) {
+					// this relation only stores a single model object, not an array
+					// but let's make it consistent
+					$related_objects = [$related_objects];
+				}
+				foreach ($related_objects as $related_object) {
+					// only refresh their cache if they're in memory
+					if ($related_object instanceof EE_Base_Class) {
+						$related_object->clear_cache(
+							$model->get_this_model_name(),
+							$this
+						);
+					}
+				}
+			}
+		}
+	}
+
+
+	/**
+	 *        Saves this object to the database. An array may be supplied to set some values on this
+	 * object just before saving.
+	 *
+	 * @access public
+	 * @param array $set_cols_n_values keys are field names, values are their new values,
+	 *                                 if provided during the save() method (often client code will change the fields'
+	 *                                 values before calling save)
+	 * @return bool|int|string         1 on a successful update
+	 *                                 the ID of the new entry on insert
+	 *                                 0 on failure or if the model object isn't allowed to persist
+	 *                                 (as determined by EE_Base_Class::allow_persist())
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws ReflectionException
+	 */
+	public function save($set_cols_n_values = [])
+	{
+		$model = $this->get_model();
+		/**
+		 * Filters the fields we're about to save on the model object
+		 *
+		 * @param array         $set_cols_n_values
+		 * @param EE_Base_Class $model_object
+		 */
+		$set_cols_n_values = (array) apply_filters(
+			'FHEE__EE_Base_Class__save__set_cols_n_values',
+			$set_cols_n_values,
+			$this
+		);
+		// set attributes as provided in $set_cols_n_values
+		foreach ($set_cols_n_values as $column => $value) {
+			$this->set($column, $value);
+		}
+		// no changes ? then don't do anything
+		if (! $this->_has_changes && $this->ID() && $model->get_primary_key_field()->is_auto_increment()) {
+			return 0;
+		}
+		/**
+		 * Saving a model object.
+		 * Before we perform a save, this action is fired.
+		 *
+		 * @param EE_Base_Class $model_object the model object about to be saved.
+		 */
+		do_action('AHEE__EE_Base_Class__save__begin', $this);
+		if (! $this->allow_persist()) {
+			return 0;
+		}
+		// now get current attribute values
+		$save_cols_n_values = $this->_fields;
+		// if the object already has an ID, update it. Otherwise, insert it
+		// also: change the assumption about values passed to the model NOT being prepare dby the model object.
+		// They have been
+		$old_assumption_concerning_value_preparation = $model
+			->get_assumption_concerning_values_already_prepared_by_model_object();
+		$model->assume_values_already_prepared_by_model_object(true);
+		// does this model have an autoincrement PK?
+		if ($model->has_primary_key_field()) {
+			if ($model->get_primary_key_field()->is_auto_increment()) {
+				// ok check if it's set, if so: update; if not, insert
+				if (! empty($save_cols_n_values[ $model->primary_key_name() ])) {
+					$results = $model->update_by_ID($save_cols_n_values, $this->ID());
+				} else {
+					unset($save_cols_n_values[ $model->primary_key_name() ]);
+					$results = $model->insert($save_cols_n_values);
+					if ($results) {
+						// if successful, set the primary key
+						// but don't use the normal SET method, because it will check if
+						// an item with the same ID exists in the mapper & db, then
+						// will find it in the db (because we just added it) and THAT object
+						// will get added to the mapper before we can add this one!
+						// but if we just avoid using the SET method, all that headache can be avoided
+						$pk_field_name                   = $model->primary_key_name();
+						$this->_fields[ $pk_field_name ] = $results;
+						$this->_clear_cached_property($pk_field_name);
+						$model->add_to_entity_map($this);
+						$this->_update_cached_related_model_objs_fks();
+					}
+				}
+			} else {// PK is NOT auto-increment
+				// so check if one like it already exists in the db
+				if ($model->exists_by_ID($this->ID())) {
+					if (WP_DEBUG && ! $this->in_entity_map()) {
+						throw new EE_Error(
+							sprintf(
+								esc_html__(
+									'Using a model object %1$s that is NOT in the entity map, can lead to unexpected errors. You should either: %4$s 1. Put it in the entity mapper by calling %2$s %4$s 2. Discard this model object and use what is in the entity mapper %4$s 3. Fetch from the database using %3$s',
+									'event_espresso'
+								),
+								get_class($this),
+								get_class($model) . '::instance()->add_to_entity_map()',
+								get_class($model) . '::instance()->get_one_by_ID()',
+								'<br />'
+							)
+						);
+					}
+					$results = $model->update_by_ID($save_cols_n_values, $this->ID());
+				} else {
+					$results = $model->insert($save_cols_n_values);
+					$this->_update_cached_related_model_objs_fks();
+				}
+			}
+		} else {// there is NO primary key
+			$already_in_db = false;
+			foreach ($model->unique_indexes() as $index) {
+				$uniqueness_where_params = array_intersect_key($save_cols_n_values, $index->fields());
+				if ($model->exists([$uniqueness_where_params])) {
+					$already_in_db = true;
+				}
+			}
+			if ($already_in_db) {
+				$combined_pk_fields_n_values = array_intersect_key(
+					$save_cols_n_values,
+					$model->get_combined_primary_key_fields()
+				);
+				$results                     = $model->update(
+					$save_cols_n_values,
+					$combined_pk_fields_n_values
+				);
+			} else {
+				$results = $model->insert($save_cols_n_values);
+			}
+		}
+		// restore the old assumption about values being prepared by the model object
+		$model->assume_values_already_prepared_by_model_object(
+			$old_assumption_concerning_value_preparation
+		);
+		/**
+		 * After saving the model object this action is called
+		 *
+		 * @param EE_Base_Class $model_object which was just saved
+		 * @param boolean|int   $results      if it were updated, TRUE or FALSE; if it were newly inserted
+		 *                                    the new ID (or 0 if an error occurred and it wasn't updated)
+		 */
+		do_action('AHEE__EE_Base_Class__save__end', $this, $results);
+		$this->_has_changes = false;
+		return $results;
+	}
+
+
+	/**
+	 * Updates the foreign key on related models objects pointing to this to have this model object's ID
+	 * as their foreign key.  If the cached related model objects already exist in the db, saves them (so that the DB
+	 * is consistent) Especially useful in case we JUST added this model object ot the database and we want to let its
+	 * cached relations with foreign keys to it know about that change. Eg: we've created a transaction but haven't
+	 * saved it to the db. We also create a registration and don't save it to the DB, but we DO cache it on the
+	 * transaction. Now, when we save the transaction, the registration's TXN_ID will be automatically updated, whether
+	 * or not they exist in the DB (if they do, their DB records will be automatically updated)
+	 *
+	 * @return void
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected function _update_cached_related_model_objs_fks()
+	{
+		$model = $this->get_model();
+		foreach ($model->relation_settings() as $relation_name => $relation_obj) {
+			if ($relation_obj instanceof EE_Has_Many_Relation) {
+				foreach ($this->get_all_from_cache($relation_name) as $related_model_obj_in_cache) {
+					$fk_to_this = $related_model_obj_in_cache->get_model()->get_foreign_key_to(
+						$model->get_this_model_name()
+					);
+					$related_model_obj_in_cache->set($fk_to_this->get_name(), $this->ID());
+					if ($related_model_obj_in_cache->ID()) {
+						$related_model_obj_in_cache->save();
+					}
+				}
+			}
+		}
+	}
+
+
+	/**
+	 * Saves this model object and its NEW cached relations to the database.
+	 * (Meaning, for now, IT DOES NOT WORK if the cached items already exist in the DB.
+	 * In order for that to work, we would need to mark model objects as dirty/clean...
+	 * because otherwise, there's a potential for infinite looping of saving
+	 * Saves the cached related model objects, and ensures the relation between them
+	 * and this object and properly setup
+	 *
+	 * @return int ID of new model object on save; 0 on failure+
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function save_new_cached_related_model_objs()
+	{
+		// make sure this has been saved
+		if (! $this->ID()) {
+			$id = $this->save();
+		} else {
+			$id = $this->ID();
+		}
+		// now save all the NEW cached model objects  (ie they don't exist in the DB)
+		foreach ($this->get_model()->relation_settings() as $relation_name => $relationObj) {
+			if ($this->_model_relations[ $relation_name ]) {
+				// is this a relation where we should expect just ONE related object (ie, EE_Belongs_To_relation)
+				// or MANY related objects (ie, EE_HABTM_Relation or EE_Has_Many_Relation)?
+				/* @var $related_model_obj EE_Base_Class */
+				if ($relationObj instanceof EE_Belongs_To_Relation) {
+					// add a relation to that relation type (which saves the appropriate thing in the process)
+					// but ONLY if it DOES NOT exist in the DB
+					$related_model_obj = $this->_model_relations[ $relation_name ];
+					// if( ! $related_model_obj->ID()){
+					$this->_add_relation_to($related_model_obj, $relation_name);
+					$related_model_obj->save_new_cached_related_model_objs();
+					// }
+				} else {
+					foreach ($this->_model_relations[ $relation_name ] as $related_model_obj) {
+						// add a relation to that relation type (which saves the appropriate thing in the process)
+						// but ONLY if it DOES NOT exist in the DB
+						// if( ! $related_model_obj->ID()){
+						$this->_add_relation_to($related_model_obj, $relation_name);
+						$related_model_obj->save_new_cached_related_model_objs();
+						// }
+					}
+				}
+			}
+		}
+		return $id;
+	}
+
+
+	/**
+	 * for getting a model while instantiated.
+	 *
+	 * @return EEM_Base | EEM_CPT_Base
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_model()
+	{
+		if (! $this->_model) {
+			$modelName    = self::_get_model_classname(get_class($this));
+			$this->_model = self::_get_model_instance_with_name($modelName, $this->_timezone);
+		} else {
+			$this->_model->set_timezone($this->_timezone);
+		}
+		return $this->_model;
+	}
+
+
+	/**
+	 * @param $props_n_values
+	 * @param $classname
+	 * @return mixed bool|EE_Base_Class|EEM_CPT_Base
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected static function _get_object_from_entity_mapper($props_n_values, $classname)
+	{
+		// TODO: will not work for Term_Relationships because they have no PK!
+		$primary_id_ref = self::_get_primary_key_name($classname);
+		if (
+			array_key_exists($primary_id_ref, $props_n_values)
+			&& ! empty($props_n_values[ $primary_id_ref ])
+		) {
+			$id = $props_n_values[ $primary_id_ref ];
+			return self::_get_model($classname)->get_from_entity_map($id);
+		}
+		return false;
+	}
+
+
+	/**
+	 * This is called by child static "new_instance" method and we'll check to see if there is an existing db entry for
+	 * the primary key (if present in incoming values). If there is a key in the incoming array that matches the
+	 * primary key for the model AND it is not null, then we check the db. If there's a an object we return it.  If not
+	 * we return false.
+	 *
+	 * @param array  $props_n_values    incoming array of properties and their values
+	 * @param string $classname         the classname of the child class
+	 * @param null   $timezone
+	 * @param array  $date_formats      incoming date_formats in an array where the first value is the
+	 *                                  date_format and the second value is the time format
+	 * @return mixed (EE_Base_Class|bool)
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	protected static function _check_for_object($props_n_values, $classname, $timezone = '', $date_formats = [])
+	{
+		$existing = null;
+		$model    = self::_get_model($classname, $timezone);
+		if ($model->has_primary_key_field()) {
+			$primary_id_ref = self::_get_primary_key_name($classname);
+			if (
+				array_key_exists($primary_id_ref, $props_n_values)
+				&& ! empty($props_n_values[ $primary_id_ref ])
+			) {
+				$existing = $model->get_one_by_ID(
+					$props_n_values[ $primary_id_ref ]
+				);
+			}
+		} elseif ($model->has_all_combined_primary_key_fields($props_n_values)) {
+			// no primary key on this model, but there's still a matching item in the DB
+			$existing = self::_get_model($classname, $timezone)->get_one_by_ID(
+				self::_get_model($classname, $timezone)
+					->get_index_primary_key_string($props_n_values)
+			);
+		}
+		if ($existing) {
+			// set date formats if present before setting values
+			if (! empty($date_formats) && is_array($date_formats)) {
+				$existing->set_date_format($date_formats[0]);
+				$existing->set_time_format($date_formats[1]);
+			} else {
+				// set default formats for date and time
+				$existing->set_date_format(get_option('date_format'));
+				$existing->set_time_format(get_option('time_format'));
+			}
+			foreach ($props_n_values as $property => $field_value) {
+				$existing->set($property, $field_value);
+			}
+			return $existing;
+		}
+		return false;
+	}
+
+
+	/**
+	 * Gets the EEM_*_Model for this class
+	 *
+	 * @access public now, as this is more convenient
+	 * @param      $classname
+	 * @param null $timezone
+	 * @return EEM_Base
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	protected static function _get_model($classname, $timezone = '')
+	{
+		// find model for this class
+		if (! $classname) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						'What were you thinking calling _get_model(%s)?? You need to specify the class name',
+						'event_espresso'
+					),
+					$classname
+				)
+			);
+		}
+		$modelName = self::_get_model_classname($classname);
+		return self::_get_model_instance_with_name($modelName, $timezone);
+	}
+
+
+	/**
+	 * Gets the model instance (eg instance of EEM_Attendee) given its classname (eg EE_Attendee)
+	 *
+	 * @param string $model_classname
+	 * @param null   $timezone
+	 * @return EEM_Base
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	protected static function _get_model_instance_with_name($model_classname, $timezone = '')
+	{
+		$model_classname = str_replace('EEM_', '', $model_classname);
+		$model           = EE_Registry::instance()->load_model($model_classname);
+		$model->set_timezone($timezone);
+		return $model;
+	}
+
+
+	/**
+	 * If a model name is provided (eg Registration), gets the model classname for that model.
+	 * Also works if a model class's classname is provided (eg EE_Registration).
+	 *
+	 * @param string|null $model_name
+	 * @return string like EEM_Attendee
+	 */
+	private static function _get_model_classname($model_name = '')
+	{
+		return strpos((string) $model_name, 'EE_') === 0
+			? str_replace('EE_', 'EEM_', $model_name)
+			: 'EEM_' . $model_name;
+	}
+
+
+	/**
+	 * returns the name of the primary key attribute
+	 *
+	 * @param null $classname
+	 * @return string
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	protected static function _get_primary_key_name($classname = null)
+	{
+		if (! $classname) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__('What were you thinking calling _get_primary_key_name(%s)', 'event_espresso'),
+					$classname
+				)
+			);
+		}
+		return self::_get_model($classname)->get_primary_key_field()->get_name();
+	}
+
+
+	/**
+	 * Gets the value of the primary key.
+	 * If the object hasn't yet been saved, it should be whatever the model field's default was
+	 * (eg, if this were the EE_Event class, look at the primary key field on EEM_Event and see what its default value
+	 * is. Usually defaults for integer primary keys are 0; string primary keys are usually NULL).
+	 *
+	 * @return mixed, if the primary key is of type INT it'll be an int. Otherwise it could be a string
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function ID()
+	{
+		$model = $this->get_model();
+		// now that we know the name of the variable, use a variable variable to get its value and return its
+		if ($model->has_primary_key_field()) {
+			return $this->_fields[ $model->primary_key_name() ];
+		}
+		return $model->get_index_primary_key_string($this->_fields);
+	}
+
+
+	/**
+	 * @param EE_Base_Class|int|string $otherModelObjectOrID
+	 * @param string                   $relation_name
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 * @since   5.0.0.p
+	 */
+	public function hasRelation($otherModelObjectOrID, string $relation_name): bool
+	{
+		$other_model = self::_get_model_instance_with_name(
+			self::_get_model_classname($relation_name),
+			$this->_timezone
+		);
+		$primary_key = $other_model->primary_key_name();
+		/** @var EE_Base_Class $otherModelObject */
+		$otherModelObject = $other_model->ensure_is_obj($otherModelObjectOrID, $relation_name);
+		return $this->count_related($relation_name, [[$primary_key => $otherModelObject->ID()]]) > 0;
+	}
+
+
+	/**
+	 * Adds a relationship to the specified EE_Base_Class object, given the relationship's name. Eg, if the current
+	 * model is related to a group of events, the $relation_name should be 'Event', and should be a key in the EE
+	 * Model's $_model_relations array. If this model object doesn't exist in the DB, just caches the related thing
+	 *
+	 * @param mixed  $otherObjectModelObjectOrID       EE_Base_Class or the ID of the other object
+	 * @param string $relation_name                    eg 'Events','Question',etc.
+	 *                                                 an attendee to a group, you also want to specify which role they
+	 *                                                 will have in that group. So you would use this parameter to
+	 *                                                 specify array('role-column-name'=>'role-id')
+	 * @param array  $extra_join_model_fields_n_values You can optionally include an array of key=>value pairs that
+	 *                                                 allow you to further constrict the relation to being added.
+	 *                                                 However, keep in mind that the columns (keys) given must match a
+	 *                                                 column on the JOIN table and currently only the HABTM models
+	 *                                                 accept these additional conditions.  Also remember that if an
+	 *                                                 exact match isn't found for these extra cols/val pairs, then a
+	 *                                                 NEW row is created in the join table.
+	 * @param null   $cache_id
+	 * @return EE_Base_Class the object the relation was added to
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function _add_relation_to(
+		$otherObjectModelObjectOrID,
+		$relation_name,
+		$extra_join_model_fields_n_values = [],
+		$cache_id = null
+	) {
+		$model = $this->get_model();
+		// if this thing exists in the DB, save the relation to the DB
+		if ($this->ID()) {
+			$otherObject = $model->add_relationship_to(
+				$this,
+				$otherObjectModelObjectOrID,
+				$relation_name,
+				$extra_join_model_fields_n_values
+			);
+			// clear cache so future get_many_related and get_first_related() return new results.
+			$this->clear_cache($relation_name, $otherObject, true);
+			if ($otherObject instanceof EE_Base_Class) {
+				$otherObject->clear_cache($model->get_this_model_name(), $this);
+			}
+		} else {
+			// this thing doesn't exist in the DB,  so just cache it
+			if (! $otherObjectModelObjectOrID instanceof EE_Base_Class) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							'Before a model object is saved to the database, calls to _add_relation_to must be passed an actual object, not just an ID. You provided %s as the model object to a %s',
+							'event_espresso'
+						),
+						$otherObjectModelObjectOrID,
+						get_class($this)
+					)
+				);
+			}
+			$otherObject = $otherObjectModelObjectOrID;
+			$this->cache($relation_name, $otherObjectModelObjectOrID, $cache_id);
+		}
+		if ($otherObject instanceof EE_Base_Class) {
+			// fix the reciprocal relation too
+			if ($otherObject->ID()) {
+				// its saved so assumed relations exist in the DB, so we can just
+				// clear the cache so future queries use the updated info in the DB
+				$otherObject->clear_cache(
+					$model->get_this_model_name(),
+					null,
+					true
+				);
+			} else {
+				// it's not saved, so it caches relations like this
+				$otherObject->cache($model->get_this_model_name(), $this);
+			}
+		}
+		return $otherObject;
+	}
+
+
+	/**
+	 * Removes a relationship to the specified EE_Base_Class object, given the relationships' name. Eg, if the current
+	 * model is related to a group of events, the $relation_name should be 'Events', and should be a key in the EE
+	 * Model's $_model_relations array. If this model object doesn't exist in the DB, just removes the related thing
+	 * from the cache
+	 *
+	 * @param mixed  $otherObjectModelObjectOrID
+	 *                EE_Base_Class or the ID of the other object, OR an array key into the cache if this isn't saved
+	 *                to the DB yet
+	 * @param string $relation_name
+	 * @param array  $where_query
+	 *                You can optionally include an array of key=>value pairs that allow you to further constrict the
+	 *                relation to being added. However, keep in mind that the columns (keys) given must match a column
+	 *                on the JOIN table and currently only the HABTM models accept these additional conditions. Also
+	 *                remember that if an exact match isn't found for these extra cols/val pairs, then no row is
+	 *                deleted.
+	 * @return EE_Base_Class the relation was removed from
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function _remove_relation_to($otherObjectModelObjectOrID, $relation_name, $where_query = [])
+	{
+		if ($this->ID()) {
+			// if this exists in the DB, save the relation change to the DB too
+			$otherObject = $this->get_model()->remove_relationship_to(
+				$this,
+				$otherObjectModelObjectOrID,
+				$relation_name,
+				$where_query
+			);
+			$this->clear_cache(
+				$relation_name,
+				$otherObject
+			);
+		} else {
+			// this doesn't exist in the DB, just remove it from the cache
+			$otherObject = $this->clear_cache(
+				$relation_name,
+				$otherObjectModelObjectOrID
+			);
+		}
+		if ($otherObject instanceof EE_Base_Class) {
+			$otherObject->clear_cache(
+				$this->get_model()->get_this_model_name(),
+				$this
+			);
+		}
+		return $otherObject;
+	}
+
+
+	/**
+	 * Removes ALL the related things for the $relation_name.
+	 *
+	 * @param string $relation_name
+	 * @param array  $where_query_params @see
+	 *                                   https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
+	 * @return EE_Base_Class
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function _remove_relations($relation_name, $where_query_params = [])
+	{
+		if ($this->ID()) {
+			// if this exists in the DB, save the relation change to the DB too
+			$otherObjects = $this->get_model()->remove_relations(
+				$this,
+				$relation_name,
+				$where_query_params
+			);
+			$this->clear_cache(
+				$relation_name,
+				null,
+				true
+			);
+		} else {
+			// this doesn't exist in the DB, just remove it from the cache
+			$otherObjects = $this->clear_cache(
+				$relation_name,
+				null,
+				true
+			);
+		}
+		if (is_array($otherObjects)) {
+			foreach ($otherObjects as $otherObject) {
+				$otherObject->clear_cache(
+					$this->get_model()->get_this_model_name(),
+					$this
+				);
+			}
+		}
+		return $otherObjects;
+	}
+
+
+	/**
+	 * Gets all the related model objects of the specified type. Eg, if the current class if
+	 * EE_Event, you could call $this->get_many_related('Registration') to get an array of all the
+	 * EE_Registration objects which related to this event. Note: by default, we remove the "default query params"
+	 * because we want to get even deleted items etc.
+	 *
+	 * @param string      $relation_name key in the model's _model_relations array
+	 * @param array|null  $query_params  @see
+	 *                              https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md#0-where-conditions
+	 * @return EE_Base_Class[]     Results not necessarily indexed by IDs, because some results might not have primary
+	 *                              keys or might not be saved yet. Consider using EEM_Base::get_IDs() on these
+	 *                              results if you want IDs
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_many_related($relation_name, $query_params = [])
+	{
+		if ($this->ID()) {
+			// this exists in the DB, so get the related things from either the cache or the DB
+			// if there are query parameters, forget about caching the related model objects.
+			if ($query_params) {
+				$related_model_objects = $this->get_model()->get_all_related(
+					$this,
+					$relation_name,
+					$query_params
+				);
+			} else {
+				// did we already cache the result of this query?
+				$cached_results = $this->get_all_from_cache($relation_name);
+				if (! $cached_results) {
+					$related_model_objects = $this->get_model()->get_all_related(
+						$this,
+						$relation_name,
+						$query_params
+					);
+					// if no query parameters were passed, then we got all the related model objects
+					// for that relation. We can cache them then.
+					foreach ($related_model_objects as $related_model_object) {
+						$this->cache($relation_name, $related_model_object);
+					}
+				} else {
+					$related_model_objects = $cached_results;
+				}
+			}
+		} else {
+			// this doesn't exist in the DB, so just get the related things from the cache
+			$related_model_objects = $this->get_all_from_cache($relation_name);
+		}
+		return $related_model_objects;
+	}
+
+
+	/**
+	 * Instead of getting the related model objects, simply counts them. Ignores default_where_conditions by default,
+	 * unless otherwise specified in the $query_params
+	 *
+	 * @param string $relation_name  model_name like 'Event', or 'Registration'
+	 * @param array  $query_params   @see
+	 *                               https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @param string $field_to_count name of field to count by. By default, uses primary key
+	 * @param bool   $distinct       if we want to only count the distinct values for the column then you can trigger
+	 *                               that by the setting $distinct to TRUE;
+	 * @return int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function count_related($relation_name, $query_params = [], $field_to_count = null, $distinct = false)
+	{
+		return $this->get_model()->count_related(
+			$this,
+			$relation_name,
+			$query_params,
+			$field_to_count,
+			$distinct
+		);
+	}
+
+
+	/**
+	 * Instead of getting the related model objects, simply sums up the values of the specified field.
+	 * Note: ignores default_where_conditions by default, unless otherwise specified in the $query_params
+	 *
+	 * @param string $relation_name model_name like 'Event', or 'Registration'
+	 * @param array  $query_params  @see
+	 *                              https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @param string $field_to_sum  name of field to count by.
+	 *                              By default, uses primary key
+	 *                              (which doesn't make much sense, so you should probably change it)
+	 * @return int
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function sum_related($relation_name, $query_params = [], $field_to_sum = null)
+	{
+		return $this->get_model()->sum_related(
+			$this,
+			$relation_name,
+			$query_params,
+			$field_to_sum
+		);
+	}
+
+
+	/**
+	 * Gets the first (ie, one) related model object of the specified type.
+	 *
+	 * @param string $relation_name key in the model's _model_relations array
+	 * @param array  $query_params  @see
+	 *                              https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return EE_Base_Class|null (not an array, a single object)
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function get_first_related(string $relation_name, array $query_params = []): ?EE_Base_Class
+	{
+		$model = $this->get_model();
+		if ($this->ID()) {// this exists in the DB, get from the cache OR the DB
+			// if they've provided some query parameters, don't bother trying to cache the result
+			// also make sure we're not caching the result of get_first_related
+			// on a relation which should have an array of objects (because the cache might have an array of objects)
+			if (
+				$query_params
+				|| ! $model->related_settings_for($relation_name) instanceof EE_Belongs_To_Relation
+			) {
+				$related_model_object = $model->get_first_related(
+					$this,
+					$relation_name,
+					$query_params
+				);
+			} else {
+				// first, check if we've already cached the result of this query
+				$cached_result = $this->get_one_from_cache($relation_name);
+				if (! $cached_result) {
+					$related_model_object = $model->get_first_related(
+						$this,
+						$relation_name,
+						$query_params
+					);
+					$this->cache($relation_name, $related_model_object);
+				} else {
+					$related_model_object = $cached_result;
+				}
+			}
+		} else {
+			$related_model_object = null;
+			// this doesn't exist in the Db,
+			// but maybe the relation is of type belongs to, and so the related thing might
+			if ($model->related_settings_for($relation_name) instanceof EE_Belongs_To_Relation) {
+				$related_model_object = $model->get_first_related(
+					$this,
+					$relation_name,
+					$query_params
+				);
+			}
+			// this doesn't exist in the DB and apparently the thing it belongs to doesn't either,
+			// just get what's cached on this object
+			if (! $related_model_object) {
+				$related_model_object = $this->get_one_from_cache($relation_name);
+			}
+		}
+		return $related_model_object;
+	}
+
+
+	/**
+	 * Does a delete on all related objects of type $relation_name and removes
+	 * the current model object's relation to them. If they can't be deleted (because
+	 * of blocking related model objects) does nothing. If the related model objects are
+	 * soft-deletable, they will be soft-deleted regardless of related blocking model objects.
+	 * If this model object doesn't exist yet in the DB, just removes its related things
+	 *
+	 * @param string $relation_name
+	 * @param array  $query_params @see
+	 *                             https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return int how many deleted
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function delete_related($relation_name, $query_params = [])
+	{
+		if ($this->ID()) {
+			$count = $this->get_model()->delete_related(
+				$this,
+				$relation_name,
+				$query_params
+			);
+		} else {
+			$count = count($this->get_all_from_cache($relation_name));
+			$this->clear_cache($relation_name, null, true);
+		}
+		return $count;
+	}
+
+
+	/**
+	 * Does a hard delete (ie, removes the DB row) on all related objects of type $relation_name and removes
+	 * the current model object's relation to them. If they can't be deleted (because
+	 * of blocking related model objects) just does a soft delete on it instead, if possible.
+	 * If the related thing isn't a soft-deletable model object, this function is identical
+	 * to delete_related(). If this model object doesn't exist in the DB, just remove its related things
+	 *
+	 * @param string $relation_name
+	 * @param array  $query_params @see
+	 *                             https://github.com/eventespresso/event-espresso-core/tree/master/docs/G--Model-System/model-query-params.md
+	 * @return int how many deleted (including those soft deleted)
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function delete_related_permanently($relation_name, $query_params = [])
+	{
+		$count = $this->ID()
+			? $this->get_model()->delete_related_permanently(
+				$this,
+				$relation_name,
+				$query_params
+			)
+			: count($this->get_all_from_cache($relation_name));
+
+		$this->clear_cache($relation_name, null, true);
+		return $count;
+	}
+
+
+	/**
+	 * is_set
+	 * Just a simple utility function children can use for checking if property exists
+	 *
+	 * @access  public
+	 * @param string $field_name property to check
+	 * @return bool                              TRUE if existing,FALSE if not.
+	 */
+	public function is_set($field_name)
+	{
+		return isset($this->_fields[ $field_name ]);
+	}
+
+
+	/**
+	 * Just a simple utility function children can use for checking if property (or properties) exists and throwing an
+	 * EE_Error exception if they don't
+	 *
+	 * @param mixed (string|array) $properties properties to check
+	 * @return bool                              TRUE if existing, throw EE_Error if not.
+	 * @throws EE_Error
+	 */
+	protected function _property_exists($properties)
+	{
+		foreach ((array) $properties as $property_name) {
+			// first make sure this property exists
+			if (! $this->_fields[ $property_name ]) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							'Trying to retrieve a non-existent property (%s).  Double check the spelling please',
+							'event_espresso'
+						),
+						$property_name
+					)
+				);
+			}
+		}
+		return true;
+	}
+
+
+	/**
+	 * This simply returns an array of model fields for this object
+	 *
+	 * @return array
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function model_field_array()
+	{
+		$fields     = $this->get_model()->field_settings(false);
+		$properties = [];
+		// remove prepended underscore
+		foreach ($fields as $field_name => $settings) {
+			$properties[ $field_name ] = $this->get($field_name);
+		}
+		return $properties;
+	}
+
+
+	/**
+	 * Very handy general function to allow for plugins to extend any child of EE_Base_Class.
+	 * If a method is called on a child of EE_Base_Class that doesn't exist, this function is called
+	 * (http://www.garfieldtech.com/blog/php-magic-call) and passed the method's name and arguments.
+	 * Instead of requiring a plugin to extend the EE_Base_Class
+	 * (which works fine is there's only 1 plugin, but when will that happen?)
+	 * they can add a hook onto 'filters_hook_espresso__{className}__{methodName}'
+	 * (eg, filters_hook_espresso__EE_Answer__my_great_function)
+	 * and accepts 2 arguments: the object on which the function was called,
+	 * and an array of the original arguments passed to the function.
+	 * Whatever their callback function returns will be returned by this function.
+	 * Example: in functions.php (or in a plugin):
+	 *      add_filter('FHEE__EE_Answer__my_callback','my_callback',10,3);
+	 *      function my_callback($previousReturnValue,EE_Base_Class $object,$argsArray){
+	 *          $returnString= "you called my_callback! and passed args:".implode(",",$argsArray);
+	 *          return $previousReturnValue.$returnString;
+	 *      }
+	 * require('EE_Answer.class.php');
+	 * echo EE_Answer::new_instance(['REG_ID' => 2,'QST_ID' => 3,'ANS_value' => The answer is 42'])
+	 *      ->my_callback('monkeys',100);
+	 * // will output "you called my_callback! and passed args:monkeys,100"
+	 *
+	 * @param string $methodName name of method which was called on a child of EE_Base_Class, but which
+	 * @param array  $args       array of original arguments passed to the function
+	 * @return mixed whatever the plugin which calls add_filter decides
+	 * @throws EE_Error
+	 */
+	public function __call($methodName, $args)
+	{
+		$className = get_class($this);
+		$tagName   = "FHEE__{$className}__{$methodName}";
+		if (! has_filter($tagName)) {
+			throw new EE_Error(
+				sprintf(
+					esc_html__(
+						"Method %s on class %s does not exist! You can create one with the following code in functions.php or in a plugin: add_filter('%s','my_callback',10,3);function my_callback(\$previousReturnValue,EE_Base_Class \$object, \$argsArray){/*function body*/return \$whatever;}",
+						'event_espresso'
+					),
+					$methodName,
+					$className,
+					$tagName
+				)
+			);
+		}
+		return apply_filters($tagName, null, $this, $args);
+	}
+
+
+	/**
+	 * Similar to insert_post_meta, adds a record in the Extra_Meta model's table with the given key and value.
+	 * A $previous_value can be specified in case there are many meta rows with the same key
+	 *
+	 * @param string $meta_key
+	 * @param mixed  $meta_value
+	 * @param mixed  $previous_value
+	 * @return bool|int # of records updated (or BOOLEAN if we actually ended up inserting the extra meta row)
+	 *                  NOTE: if the values haven't changed, returns 0
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function update_extra_meta(string $meta_key, $meta_value, $previous_value = null)
+	{
+		$query_params = [
+			[
+				'EXM_key'  => $meta_key,
+				'OBJ_ID'   => $this->ID(),
+				'EXM_type' => $this->get_model()->get_this_model_name(),
+			],
+		];
+		if ($previous_value !== null) {
+			$query_params[0]['EXM_value'] = $meta_value;
+		}
+		$existing_rows_like_that = EEM_Extra_Meta::instance()->get_all($query_params);
+		if (! $existing_rows_like_that) {
+			return $this->add_extra_meta($meta_key, $meta_value);
+		}
+		foreach ($existing_rows_like_that as $existing_row) {
+			$existing_row->save(['EXM_value' => $meta_value]);
+		}
+		return count($existing_rows_like_that);
+	}
+
+
+	/**
+	 * Adds a new extra meta record. If $unique is set to TRUE, we'll first double-check
+	 * no other extra meta for this model object have the same key. Returns TRUE if the
+	 * extra meta row was entered, false if not
+	 *
+	 * @param string $meta_key
+	 * @param mixed  $meta_value
+	 * @param bool   $unique
+	 * @return bool
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function add_extra_meta(string $meta_key, $meta_value, bool $unique = false): bool
+	{
+		if ($unique) {
+			$existing_extra_meta = EEM_Extra_Meta::instance()->get_one(
+				[
+					[
+						'EXM_key'  => $meta_key,
+						'OBJ_ID'   => $this->ID(),
+						'EXM_type' => $this->get_model()->get_this_model_name(),
+					],
+				]
+			);
+			if ($existing_extra_meta) {
+				return false;
+			}
+		}
+		$new_extra_meta = EE_Extra_Meta::new_instance(
+			[
+				'EXM_key'   => $meta_key,
+				'EXM_value' => $meta_value,
+				'OBJ_ID'    => $this->ID(),
+				'EXM_type'  => $this->get_model()->get_this_model_name(),
+			]
+		);
+		$new_extra_meta->save();
+		return true;
+	}
+
+
+	/**
+	 * Deletes all the extra meta rows for this record as specified by key. If $meta_value
+	 * is specified, only deletes extra meta records with that value.
+	 *
+	 * @param string $meta_key
+	 * @param mixed  $meta_value
+	 * @return int|bool number of extra meta rows deleted
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function delete_extra_meta(string $meta_key, $meta_value = null)
+	{
+		$query_params = [
+			[
+				'EXM_key'  => $meta_key,
+				'OBJ_ID'   => $this->ID(),
+				'EXM_type' => $this->get_model()->get_this_model_name(),
+			],
+		];
+		if ($meta_value !== null) {
+			$query_params[0]['EXM_value'] = $meta_value;
+		}
+		return EEM_Extra_Meta::instance()->delete($query_params);
+	}
+
+
+	/**
+	 * Gets the extra meta with the given meta key. If you specify "single" we just return 1, otherwise
+	 * an array of everything found. Requires that this model actually have a relation of type EE_Has_Many_Any_Relation.
+	 * You can specify $default is case you haven't found the extra meta
+	 *
+	 * @param string     $meta_key
+	 * @param bool       $single
+	 * @param mixed      $default if we don't find anything, what should we return?
+	 * @param array|null $extra_where
+	 * @return mixed single value if $single; array if ! $single
+	 * @throws ReflectionException
+	 * @throws EE_Error
+	 */
+	public function get_extra_meta(string $meta_key, bool $single = false, $default = null, ?array $extra_where = [])
+	{
+		$query_params = [$extra_where + ['EXM_key' => $meta_key]];
+		if ($single) {
+			$result = $this->get_first_related('Extra_Meta', $query_params);
+			if ($result instanceof EE_Extra_Meta) {
+				return $result->value();
+			}
+		} else {
+			$results = $this->get_many_related('Extra_Meta', $query_params);
+			if ($results) {
+				$values = [];
+				foreach ($results as $result) {
+					if ($result instanceof EE_Extra_Meta) {
+						$values[ $result->ID() ] = $result->value();
+					}
+				}
+				return $values;
+			}
+		}
+		// if nothing discovered yet return default.
+		return apply_filters(
+			'FHEE__EE_Base_Class__get_extra_meta__default_value',
+			$default,
+			$meta_key,
+			$single,
+			$this
+		);
+	}
+
+
+	/**
+	 * Returns a simple array of all the extra meta associated with this model object.
+	 * If $one_of_each_key is true (Default), it will be an array of simple key-value pairs, keys being the
+	 * extra meta's key, and teh value being its value. However, if there are duplicate extra meta rows with
+	 * the same key, only one will be used. (eg array('foo'=>'bar','monkey'=>123))
+	 * If $one_of_each_key is false, it will return an array with the top-level keys being
+	 * the extra meta keys, but their values are also arrays, which have the extra-meta's ID as their sub-key, and
+	 * finally the extra meta's value as each sub-value. (eg
+	 * array('foo'=>array(1=>'bar',2=>'bill'),'monkey'=>array(3=>123)))
+	 *
+	 * @param bool $one_of_each_key
+	 * @return array
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function all_extra_meta_array(bool $one_of_each_key = true): array
+	{
+		$return_array = [];
+		if ($one_of_each_key) {
+			$extra_meta_objs = $this->get_many_related(
+				'Extra_Meta',
+				['group_by' => 'EXM_key']
+			);
+			foreach ($extra_meta_objs as $extra_meta_obj) {
+				if ($extra_meta_obj instanceof EE_Extra_Meta) {
+					$return_array[ $extra_meta_obj->key() ] = $extra_meta_obj->value();
+				}
+			}
+		} else {
+			$extra_meta_objs = $this->get_many_related('Extra_Meta');
+			foreach ($extra_meta_objs as $extra_meta_obj) {
+				if ($extra_meta_obj instanceof EE_Extra_Meta) {
+					if (! isset($return_array[ $extra_meta_obj->key() ])) {
+						$return_array[ $extra_meta_obj->key() ] = [];
+					}
+					$return_array[ $extra_meta_obj->key() ][ $extra_meta_obj->ID() ] = $extra_meta_obj->value();
+				}
+			}
+		}
+		return $return_array;
+	}
+
+
+	/**
+	 * Gets a pretty nice displayable nice for this model object. Often overridden
+	 *
+	 * @return string
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function name()
+	{
+		// find a field that's not a text field
+		$field_we_can_use = $this->get_model()->get_a_field_of_type('EE_Text_Field_Base');
+		if ($field_we_can_use) {
+			return $this->get($field_we_can_use->get_name());
+		}
+		$first_few_properties = $this->model_field_array();
+		$first_few_properties = array_slice($first_few_properties, 0, 3);
+		$name_parts           = [];
+		foreach ($first_few_properties as $name => $value) {
+			$name_parts[] = "$name:$value";
+		}
+		return implode(',', $name_parts);
+	}
+
+
+	/**
+	 * in_entity_map
+	 * Checks if this model object has been proven to already be in the entity map
+	 *
+	 * @return boolean
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function in_entity_map()
+	{
+		// well, if we looked, did we find it in the entity map?
+		return $this->ID() && $this->get_model()->get_from_entity_map($this->ID()) === $this;
+	}
+
+
+	/**
+	 * refresh_from_db
+	 * Makes sure the fields and values on this model object are in-sync with what's in the database.
+	 *
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error if this model object isn't in the entity mapper (because then you should
+	 * just use what's in the entity mapper and refresh it) and WP_DEBUG is TRUE
+	 */
+	public function refresh_from_db()
+	{
+		if ($this->ID() && $this->in_entity_map()) {
+			$this->get_model()->refresh_entity_map_from_db($this->ID());
+		} else {
+			// if it doesn't have ID, you shouldn't be asking to refresh it from teh database (because its not in the database)
+			// if it has an ID but it's not in the map, and you're asking me to refresh it
+			// that's kinda dangerous. You should just use what's in the entity map, or add this to the entity map if there's
+			// absolutely nothing in it for this ID
+			if (WP_DEBUG) {
+				throw new EE_Error(
+					sprintf(
+						esc_html__(
+							'Trying to refresh a model object with ID "%1$s" that\'s not in the entity map? First off: you should put it in the entity map by calling %2$s. Second off, if you want what\'s in the database right now, you should just call %3$s yourself and discard this model object.',
+							'event_espresso'
+						),
+						$this->ID(),
+						get_class($this->get_model()) . '::instance()->add_to_entity_map()',
+						get_class($this->get_model()) . '::instance()->refresh_entity_map()'
+					)
+				);
+			}
+		}
+	}
+
+
+	/**
+	 * Change $fields' values to $new_value_sql (which is a string of raw SQL)
+	 *
+	 * @param EE_Model_Field_Base[] $fields
+	 * @param string                $new_value_sql
+	 *          example: 'column_name=123',
+	 *          or 'column_name=column_name+1',
+	 *          or 'column_name= CASE
+	 *          WHEN (`column_name` + `other_column` + 5) <= `yet_another_column`
+	 *          THEN `column_name` + 5
+	 *          ELSE `column_name`
+	 *          END'
+	 *          Also updates $field on this model object with the latest value from the database.
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @since 4.9.80.p
+	 */
+	protected function updateFieldsInDB($fields, $new_value_sql)
+	{
+		// First make sure this model object actually exists in the DB. It would be silly to try to update it in the DB
+		// if it wasn't even there to start off.
+		if (! $this->ID()) {
+			$this->save();
+		}
+		global $wpdb;
+		if (empty($fields)) {
+			throw new InvalidArgumentException(
+				esc_html__(
+					'EE_Base_Class::updateFieldsInDB was passed an empty array of fields.',
+					'event_espresso'
+				)
+			);
+		}
+		$first_field = reset($fields);
+		$table_alias = $first_field->get_table_alias();
+		foreach ($fields as $field) {
+			if ($table_alias !== $field->get_table_alias()) {
+				throw new InvalidArgumentException(
+					sprintf(
+						esc_html__(
+						// @codingStandardsIgnoreStart
+							'EE_Base_Class::updateFieldsInDB was passed fields for different tables ("%1$s" and "%2$s"), which is not supported. Instead, please call the method multiple times.',
+							// @codingStandardsIgnoreEnd
+							'event_espresso'
+						),
+						$table_alias,
+						$field->get_table_alias()
+					)
+				);
+			}
+		}
+		// Ok the fields are now known to all be for the same table. Proceed with creating the SQL to update it.
+		$table_obj      = $this->get_model()->get_table_obj_by_alias($table_alias);
+		$table_pk_value = $this->ID();
+		$table_name     = $table_obj->get_table_name();
+		if ($table_obj instanceof EE_Secondary_Table) {
+			$table_pk_field_name = $table_obj->get_fk_on_table();
+		} else {
+			$table_pk_field_name = $table_obj->get_pk_column();
+		}
+
+		$query  =
+			"UPDATE `{$table_name}`
             SET "
-            . $new_value_sql
-            . $wpdb->prepare(
-                "
+			. $new_value_sql
+			. $wpdb->prepare(
+				"
             WHERE `{$table_pk_field_name}` = %d;",
-                $table_pk_value
-            );
-        $result = $wpdb->query($query);
-        foreach ($fields as $field) {
-            // If it was successful, we'd like to know the new value.
-            // If it failed, we'd also like to know the new value.
-            $new_value = $this->get_model()->get_var(
-                $this->get_model()->alter_query_params_to_restrict_by_ID(
-                    $this->get_model()->get_index_primary_key_string(
-                        $this->model_field_array()
-                    ),
-                    [
-                        'default_where_conditions' => 'minimum',
-                    ]
-                ),
-                $field->get_name()
-            );
-            $this->set_from_db(
-                $field->get_name(),
-                $new_value
-            );
-        }
-        return (bool) $result;
-    }
-
-
-    /**
-     * Nudges $field_name's value by $quantity, without any conditionals (in comparison to bumpConditionally()).
-     * Does not allow negative values, however.
-     *
-     * @param array $fields_n_quantities keys are the field names, and values are the amount by which to bump them
-     *                                   (positive or negative). One important gotcha: all these values must be
-     *                                   on the same table (eg don't pass in one field for the posts table and
-     *                                   another for the event meta table.)
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @since 4.9.80.p
-     */
-    public function adjustNumericFieldsInDb(array $fields_n_quantities)
-    {
-        global $wpdb;
-        if (empty($fields_n_quantities)) {
-            // No fields to update? Well sure, we updated them to that value just fine.
-            return true;
-        }
-        $fields             = [];
-        $set_sql_statements = [];
-        foreach ($fields_n_quantities as $field_name => $quantity) {
-            $field       = $this->get_model()->field_settings_for($field_name, true);
-            $fields[]    = $field;
-            $column_name = $field->get_table_column();
-
-            $abs_qty = absint($quantity);
-            if ($quantity > 0) {
-                // don't let the value be negative as often these fields are unsigned
-                $set_sql_statements[] = $wpdb->prepare(
-                    "`{$column_name}` = `{$column_name}` + %d",
-                    $abs_qty
-                );
-            } else {
-                $set_sql_statements[] = $wpdb->prepare(
-                    "`{$column_name}` = CASE
+				$table_pk_value
+			);
+		$result = $wpdb->query($query);
+		foreach ($fields as $field) {
+			// If it was successful, we'd like to know the new value.
+			// If it failed, we'd also like to know the new value.
+			$new_value = $this->get_model()->get_var(
+				$this->get_model()->alter_query_params_to_restrict_by_ID(
+					$this->get_model()->get_index_primary_key_string(
+						$this->model_field_array()
+					),
+					[
+						'default_where_conditions' => 'minimum',
+					]
+				),
+				$field->get_name()
+			);
+			$this->set_from_db(
+				$field->get_name(),
+				$new_value
+			);
+		}
+		return (bool) $result;
+	}
+
+
+	/**
+	 * Nudges $field_name's value by $quantity, without any conditionals (in comparison to bumpConditionally()).
+	 * Does not allow negative values, however.
+	 *
+	 * @param array $fields_n_quantities keys are the field names, and values are the amount by which to bump them
+	 *                                   (positive or negative). One important gotcha: all these values must be
+	 *                                   on the same table (eg don't pass in one field for the posts table and
+	 *                                   another for the event meta table.)
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @since 4.9.80.p
+	 */
+	public function adjustNumericFieldsInDb(array $fields_n_quantities)
+	{
+		global $wpdb;
+		if (empty($fields_n_quantities)) {
+			// No fields to update? Well sure, we updated them to that value just fine.
+			return true;
+		}
+		$fields             = [];
+		$set_sql_statements = [];
+		foreach ($fields_n_quantities as $field_name => $quantity) {
+			$field       = $this->get_model()->field_settings_for($field_name, true);
+			$fields[]    = $field;
+			$column_name = $field->get_table_column();
+
+			$abs_qty = absint($quantity);
+			if ($quantity > 0) {
+				// don't let the value be negative as often these fields are unsigned
+				$set_sql_statements[] = $wpdb->prepare(
+					"`{$column_name}` = `{$column_name}` + %d",
+					$abs_qty
+				);
+			} else {
+				$set_sql_statements[] = $wpdb->prepare(
+					"`{$column_name}` = CASE
                        WHEN (`{$column_name}` >= %d)
                        THEN `{$column_name}` - %d
                        ELSE 0
                     END",
-                    $abs_qty,
-                    $abs_qty
-                );
-            }
-        }
-        return $this->updateFieldsInDB(
-            $fields,
-            implode(', ', $set_sql_statements)
-        );
-    }
-
-
-    /**
-     * Increases the value of the field $field_name_to_bump by $quantity, but only if the values of
-     * $field_name_to_bump plus $field_name_affecting_total and $quantity won't exceed $limit_field_name's value.
-     * For example, this is useful when bumping the value of TKT_reserved, TKT_sold, DTT_reserved or DTT_sold.
-     * Returns true if the value was successfully bumped, and updates the value on this model object.
-     * Otherwise returns false.
-     *
-     * @param string $field_name_to_bump
-     * @param string $field_name_affecting_total
-     * @param string $limit_field_name
-     * @param int    $quantity
-     * @return bool
-     * @throws EE_Error
-     * @throws InvalidArgumentException
-     * @throws InvalidDataTypeException
-     * @throws InvalidInterfaceException
-     * @throws ReflectionException
-     * @since 4.9.80.p
-     */
-    public function incrementFieldConditionallyInDb(
-        $field_name_to_bump,
-        $field_name_affecting_total,
-        $limit_field_name,
-        $quantity
-    ) {
-        global $wpdb;
-        $field       = $this->get_model()->field_settings_for($field_name_to_bump, true);
-        $column_name = $field->get_table_column();
-
-        $field_affecting_total  = $this->get_model()->field_settings_for($field_name_affecting_total, true);
-        $column_affecting_total = $field_affecting_total->get_table_column();
-
-        $limiting_field  = $this->get_model()->field_settings_for($limit_field_name, true);
-        $limiting_column = $limiting_field->get_table_column();
-        return $this->updateFieldsInDB(
-            [$field],
-            $wpdb->prepare(
-                "`{$column_name}` =
+					$abs_qty,
+					$abs_qty
+				);
+			}
+		}
+		return $this->updateFieldsInDB(
+			$fields,
+			implode(', ', $set_sql_statements)
+		);
+	}
+
+
+	/**
+	 * Increases the value of the field $field_name_to_bump by $quantity, but only if the values of
+	 * $field_name_to_bump plus $field_name_affecting_total and $quantity won't exceed $limit_field_name's value.
+	 * For example, this is useful when bumping the value of TKT_reserved, TKT_sold, DTT_reserved or DTT_sold.
+	 * Returns true if the value was successfully bumped, and updates the value on this model object.
+	 * Otherwise returns false.
+	 *
+	 * @param string $field_name_to_bump
+	 * @param string $field_name_affecting_total
+	 * @param string $limit_field_name
+	 * @param int    $quantity
+	 * @return bool
+	 * @throws EE_Error
+	 * @throws InvalidArgumentException
+	 * @throws InvalidDataTypeException
+	 * @throws InvalidInterfaceException
+	 * @throws ReflectionException
+	 * @since 4.9.80.p
+	 */
+	public function incrementFieldConditionallyInDb(
+		$field_name_to_bump,
+		$field_name_affecting_total,
+		$limit_field_name,
+		$quantity
+	) {
+		global $wpdb;
+		$field       = $this->get_model()->field_settings_for($field_name_to_bump, true);
+		$column_name = $field->get_table_column();
+
+		$field_affecting_total  = $this->get_model()->field_settings_for($field_name_affecting_total, true);
+		$column_affecting_total = $field_affecting_total->get_table_column();
+
+		$limiting_field  = $this->get_model()->field_settings_for($limit_field_name, true);
+		$limiting_column = $limiting_field->get_table_column();
+		return $this->updateFieldsInDB(
+			[$field],
+			$wpdb->prepare(
+				"`{$column_name}` =
             CASE
                WHEN ((`{$column_name}` + `{$column_affecting_total}` + %d) <= `{$limiting_column}`) OR `{$limiting_column}` = %d
                THEN `{$column_name}` + %d
                ELSE `{$column_name}`
             END",
-                $quantity,
-                EE_INF_IN_DB,
-                $quantity
-            )
-        );
-    }
-
-
-    /**
-     * Because some other plugins, like Advanced Cron Manager, expect all objects to have this method
-     * (probably a bad assumption they have made, oh well)
-     *
-     * @return string
-     */
-    public function __toString()
-    {
-        try {
-            return sprintf('%s (%s)', $this->name(), $this->ID());
-        } catch (Exception $e) {
-            EE_Error::add_error($e->getMessage(), __FILE__, __FUNCTION__, __LINE__);
-            return '';
-        }
-    }
-
-
-    /**
-     * Clear related model objects if they're already in the DB, because otherwise when we
-     * UN-serialize this model object we'll need to be careful to add them to the entity map.
-     * This means if we have made changes to those related model objects, and want to unserialize
-     * the this model object on a subsequent request, changes to those related model objects will be lost.
-     * Instead, those related model objects should be directly serialized and stored.
-     * Eg, the following won't work:
-     * $reg = EEM_Registration::instance()->get_one_by_ID( 123 );
-     * $att = $reg->attendee();
-     * $att->set( 'ATT_fname', 'Dirk' );
-     * update_option( 'my_option', serialize( $reg ) );
-     * //END REQUEST
-     * //START NEXT REQUEST
-     * $reg = get_option( 'my_option' );
-     * $reg->attendee()->save();
-     * And would need to be replace with:
-     * $reg = EEM_Registration::instance()->get_one_by_ID( 123 );
-     * $att = $reg->attendee();
-     * $att->set( 'ATT_fname', 'Dirk' );
-     * update_option( 'my_option', serialize( $reg ) );
-     * //END REQUEST
-     * //START NEXT REQUEST
-     * $att = get_option( 'my_option' );
-     * $att->save();
-     *
-     * @return array
-     * @throws ReflectionException
-     * @throws InvalidArgumentException
-     * @throws InvalidInterfaceException
-     * @throws InvalidDataTypeException
-     * @throws EE_Error
-     */
-    public function __sleep()
-    {
-        $model = $this->get_model();
-        foreach ($model->relation_settings() as $relation_name => $relation_obj) {
-            if ($relation_obj instanceof EE_Belongs_To_Relation) {
-                $classname = 'EE_' . $model->get_this_model_name();
-                if (
-                    $this->get_one_from_cache($relation_name) instanceof $classname
-                    && $this->get_one_from_cache($relation_name)->ID()
-                ) {
-                    $this->clear_cache(
-                        $relation_name,
-                        $this->get_one_from_cache($relation_name)->ID()
-                    );
-                }
-            }
-        }
-        $this->_props_n_values_provided_in_constructor = [];
-        $properties_to_serialize                       = get_object_vars($this);
-        // don't serialize the model. It's big and that risks recursion
-        unset($properties_to_serialize['_model']);
-        return array_keys($properties_to_serialize);
-    }
-
-
-    /**
-     * restore _props_n_values_provided_in_constructor
-     * PLZ NOTE: this will reset the array to whatever fields values were present prior to serialization,
-     * and therefore should NOT be used to determine if state change has occurred since initial construction.
-     * At best, you would only be able to detect if state change has occurred during THIS request.
-     */
-    public function __wakeup()
-    {
-        $this->_props_n_values_provided_in_constructor = $this->_fields;
-    }
-
-
-    /**
-     * Usage of this magic method is to ensure any internally cached references to object instances that must remain
-     * distinct with the clone host instance are also cloned.
-     */
-    public function __clone()
-    {
-        // handle DateTimes (this is handled in here because there's no one specific child class that uses datetimes).
-        foreach ($this->_fields as $field => $value) {
-            if ($value instanceof DateTime) {
-                $this->_fields[ $field ] = clone $value;
-            }
-        }
-    }
-
-
-    public function debug()
-    {
-        $this->echoProperty(get_class($this), get_object_vars($this));
-        echo "\n\n";
-    }
-
-
-    private function echoProperty($field, $value, int $indent = 0)
-    {
-        $bullets = str_repeat(' -', $indent) . ' ';
-        $field = strpos($field, '_') === 0 ? substr($field, 1) : $field;
-        echo "\n$bullets$field: ";
-        if ($value instanceof EEM_Base) {
-            $value = get_class($value);
-        } elseif (is_object($value)) {
-            $value = get_object_vars($value);
-        }
-        if (is_array($value)) {
-            foreach ($value as $f => $v ) {
-                $this->echoProperty($f, $v, $indent+1);
-            }
-            return;
-        }
-        ob_start();
-        var_dump($value);
-        echo rtrim(ob_get_clean(), "\n");
-    }
+				$quantity,
+				EE_INF_IN_DB,
+				$quantity
+			)
+		);
+	}
+
+
+	/**
+	 * Because some other plugins, like Advanced Cron Manager, expect all objects to have this method
+	 * (probably a bad assumption they have made, oh well)
+	 *
+	 * @return string
+	 */
+	public function __toString()
+	{
+		try {
+			return sprintf('%s (%s)', $this->name(), $this->ID());
+		} catch (Exception $e) {
+			EE_Error::add_error($e->getMessage(), __FILE__, __FUNCTION__, __LINE__);
+			return '';
+		}
+	}
+
+
+	/**
+	 * Clear related model objects if they're already in the DB, because otherwise when we
+	 * UN-serialize this model object we'll need to be careful to add them to the entity map.
+	 * This means if we have made changes to those related model objects, and want to unserialize
+	 * the this model object on a subsequent request, changes to those related model objects will be lost.
+	 * Instead, those related model objects should be directly serialized and stored.
+	 * Eg, the following won't work:
+	 * $reg = EEM_Registration::instance()->get_one_by_ID( 123 );
+	 * $att = $reg->attendee();
+	 * $att->set( 'ATT_fname', 'Dirk' );
+	 * update_option( 'my_option', serialize( $reg ) );
+	 * //END REQUEST
+	 * //START NEXT REQUEST
+	 * $reg = get_option( 'my_option' );
+	 * $reg->attendee()->save();
+	 * And would need to be replace with:
+	 * $reg = EEM_Registration::instance()->get_one_by_ID( 123 );
+	 * $att = $reg->attendee();
+	 * $att->set( 'ATT_fname', 'Dirk' );
+	 * update_option( 'my_option', serialize( $reg ) );
+	 * //END REQUEST
+	 * //START NEXT REQUEST
+	 * $att = get_option( 'my_option' );
+	 * $att->save();
+	 *
+	 * @return array
+	 * @throws ReflectionException
+	 * @throws InvalidArgumentException
+	 * @throws InvalidInterfaceException
+	 * @throws InvalidDataTypeException
+	 * @throws EE_Error
+	 */
+	public function __sleep()
+	{
+		$model = $this->get_model();
+		foreach ($model->relation_settings() as $relation_name => $relation_obj) {
+			if ($relation_obj instanceof EE_Belongs_To_Relation) {
+				$classname = 'EE_' . $model->get_this_model_name();
+				if (
+					$this->get_one_from_cache($relation_name) instanceof $classname
+					&& $this->get_one_from_cache($relation_name)->ID()
+				) {
+					$this->clear_cache(
+						$relation_name,
+						$this->get_one_from_cache($relation_name)->ID()
+					);
+				}
+			}
+		}
+		$this->_props_n_values_provided_in_constructor = [];
+		$properties_to_serialize                       = get_object_vars($this);
+		// don't serialize the model. It's big and that risks recursion
+		unset($properties_to_serialize['_model']);
+		return array_keys($properties_to_serialize);
+	}
+
+
+	/**
+	 * restore _props_n_values_provided_in_constructor
+	 * PLZ NOTE: this will reset the array to whatever fields values were present prior to serialization,
+	 * and therefore should NOT be used to determine if state change has occurred since initial construction.
+	 * At best, you would only be able to detect if state change has occurred during THIS request.
+	 */
+	public function __wakeup()
+	{
+		$this->_props_n_values_provided_in_constructor = $this->_fields;
+	}
+
+
+	/**
+	 * Usage of this magic method is to ensure any internally cached references to object instances that must remain
+	 * distinct with the clone host instance are also cloned.
+	 */
+	public function __clone()
+	{
+		// handle DateTimes (this is handled in here because there's no one specific child class that uses datetimes).
+		foreach ($this->_fields as $field => $value) {
+			if ($value instanceof DateTime) {
+				$this->_fields[ $field ] = clone $value;
+			}
+		}
+	}
+
+
+	public function debug()
+	{
+		$this->echoProperty(get_class($this), get_object_vars($this));
+		echo "\n\n";
+	}
+
+
+	private function echoProperty($field, $value, int $indent = 0)
+	{
+		$bullets = str_repeat(' -', $indent) . ' ';
+		$field = strpos($field, '_') === 0 ? substr($field, 1) : $field;
+		echo "\n$bullets$field: ";
+		if ($value instanceof EEM_Base) {
+			$value = get_class($value);
+		} elseif (is_object($value)) {
+			$value = get_object_vars($value);
+		}
+		if (is_array($value)) {
+			foreach ($value as $f => $v ) {
+				$this->echoProperty($f, $v, $indent+1);
+			}
+			return;
+		}
+		ob_start();
+		var_dump($value);
+		echo rtrim(ob_get_clean(), "\n");
+	}
 }

Spacing +119 added lines, -119 removed lines

@@ -133,7 +133,7 @@ 
         $fieldValues = is_array($fieldValues) ? $fieldValues : [$fieldValues];
         // verify client code has not passed any invalid field names
         foreach ($fieldValues as $field_name => $field_value) {
-            if (! isset($model_fields[ $field_name ])) {
+            if ( ! isset($model_fields[$field_name])) {
                 throw new EE_Error(
                     sprintf(
                         esc_html__(
@@ -151,7 +151,7 @@ 
         $date_format     = null;
         $time_format     = null;
         $this->_timezone = EEH_DTT_Helper::get_valid_timezone_string($timezone);
-        if (! empty($date_formats) && is_array($date_formats)) {
+        if ( ! empty($date_formats) && is_array($date_formats)) {
             [$date_format, $time_format] = $date_formats;
         }
         $this->set_date_format($date_format);
@@ -162,14 +162,14 @@ 
                 // client code has indicated these field values are from the database
                 $this->set_from_db(
                     $fieldName,
-                    $fieldValues[ $fieldName ] ?? null
+                    $fieldValues[$fieldName] ?? null
                 );
             } else {
                 // we're constructing a brand new instance of the model object.
                 // Generally, this means we'll need to do more field validation
                 $this->set(
                     $fieldName,
-                    $fieldValues[ $fieldName ] ?? null,
+                    $fieldValues[$fieldName] ?? null,
                     true
                 );
             }
@@ -177,15 +177,15 @@ 
         // remember what values were passed to this constructor
         $this->_props_n_values_provided_in_constructor = $fieldValues;
         // remember in entity mapper
-        if (! $bydb && $model->has_primary_key_field() && $this->ID()) {
+        if ( ! $bydb && $model->has_primary_key_field() && $this->ID()) {
             $model->add_to_entity_map($this);
         }
         // setup all the relations
         foreach ($model->relation_settings() as $relation_name => $relation_obj) {
             if ($relation_obj instanceof EE_Belongs_To_Relation) {
-                $this->_model_relations[ $relation_name ] = null;
+                $this->_model_relations[$relation_name] = null;
             } else {
-                $this->_model_relations[ $relation_name ] = [];
+                $this->_model_relations[$relation_name] = [];
             }
         }
         /**
@@ -237,10 +237,10 @@ 
     public function get_original($field_name)
     {
         if (
-            isset($this->_props_n_values_provided_in_constructor[ $field_name ])
+            isset($this->_props_n_values_provided_in_constructor[$field_name])
             && $field_settings = $this->get_model()->field_settings_for($field_name)
         ) {
-            return $field_settings->prepare_for_get($this->_props_n_values_provided_in_constructor[ $field_name ]);
+            return $field_settings->prepare_for_get($this->_props_n_values_provided_in_constructor[$field_name]);
         }
         return null;
     }
@@ -276,7 +276,7 @@ 
         // then don't do anything
         if (
             ! $use_default
-            && $this->_fields[ $field_name ] === $field_value
+            && $this->_fields[$field_name] === $field_value
             && $this->ID()
         ) {
             return;
@@ -284,7 +284,7 @@ 
         $model              = $this->get_model();
         $this->_has_changes = true;
         $field_obj          = $model->field_settings_for($field_name);
-        if (! $field_obj instanceof EE_Model_Field_Base) {
+        if ( ! $field_obj instanceof EE_Model_Field_Base) {
             throw new EE_Error(
                 sprintf(
                     esc_html__(
@@ -307,7 +307,7 @@ 
             ? $field_obj->get_default_value()
             : $field_value;
 
-        $this->_fields[ $field_name ] = $field_obj->prepare_for_set($value);
+        $this->_fields[$field_name] = $field_obj->prepare_for_set($value);
 
         // if we're not in the constructor...
         // now check if what we set was a primary key
@@ -369,7 +369,7 @@ 
             } else {
                 $field_value = $field_obj->prepare_for_set_from_db($field_value_from_db);
             }
-            $this->_fields[ $field_name ] = $field_value;
+            $this->_fields[$field_name] = $field_value;
             $this->_clear_cached_property($field_name);
         }
     }
@@ -395,7 +395,7 @@ 
      */
     public function getCustomSelect($alias)
     {
-        return $this->custom_selection_results[ $alias ] ?? null;
+        return $this->custom_selection_results[$alias] ?? null;
     }
 
 
@@ -482,8 +482,8 @@ 
         foreach ($model_fields as $field_name => $field_obj) {
             if ($field_obj instanceof EE_Datetime_Field) {
                 $field_obj->set_timezone($this->_timezone);
-                if (isset($this->_fields[ $field_name ]) && $this->_fields[ $field_name ] instanceof DateTime) {
-                    EEH_DTT_Helper::setTimezone($this->_fields[ $field_name ], new DateTimeZone($this->_timezone));
+                if (isset($this->_fields[$field_name]) && $this->_fields[$field_name] instanceof DateTime) {
+                    EEH_DTT_Helper::setTimezone($this->_fields[$field_name], new DateTimeZone($this->_timezone));
                 }
             }
         }
@@ -541,7 +541,7 @@ 
      */
     public function get_format($full = true)
     {
-        return $full ? $this->_dt_frmt . ' ' . $this->_tm_frmt : [$this->_dt_frmt, $this->_tm_frmt];
+        return $full ? $this->_dt_frmt.' '.$this->_tm_frmt : [$this->_dt_frmt, $this->_tm_frmt];
     }
 
 
@@ -567,11 +567,11 @@ 
     public function cache($relation_name = '', $object_to_cache = null, $cache_id = null)
     {
         // its entirely possible that there IS no related object yet in which case there is nothing to cache.
-        if (! $object_to_cache instanceof EE_Base_Class) {
+        if ( ! $object_to_cache instanceof EE_Base_Class) {
             return false;
         }
         // also get "how" the object is related, or throw an error
-        if (! $relationship_to_model = $this->get_model()->related_settings_for($relation_name)) {
+        if ( ! $relationship_to_model = $this->get_model()->related_settings_for($relation_name)) {
             throw new EE_Error(
                 sprintf(
                     esc_html__('There is no relationship to %s on a %s. Cannot cache it', 'event_espresso'),
@@ -585,38 +585,38 @@ 
             // if it's a "belongs to" relationship, then there's only one related model object
             // eg, if this is a registration, there's only 1 attendee for it
             // so for these model objects just set it to be cached
-            $this->_model_relations[ $relation_name ] = $object_to_cache;
+            $this->_model_relations[$relation_name] = $object_to_cache;
             $return                                   = true;
         } else {
             // otherwise, this is the "many" side of a one to many relationship,
             // so we'll add the object to the array of related objects for that type.
             // eg: if this is an event, there are many registrations for that event,
             // so we cache the registrations in an array
-            if (! is_array($this->_model_relations[ $relation_name ])) {
+            if ( ! is_array($this->_model_relations[$relation_name])) {
                 // if for some reason, the cached item is a model object,
                 // then stick that in the array, otherwise start with an empty array
-                $this->_model_relations[ $relation_name ] =
-                    $this->_model_relations[ $relation_name ] instanceof EE_Base_Class
-                        ? [$this->_model_relations[ $relation_name ]]
+                $this->_model_relations[$relation_name] =
+                    $this->_model_relations[$relation_name] instanceof EE_Base_Class
+                        ? [$this->_model_relations[$relation_name]]
                         : [];
             }
             // first check for a cache_id which is normally empty
-            if (! empty($cache_id)) {
+            if ( ! empty($cache_id)) {
                 // if the cache_id exists, then it means we are purposely trying to cache this
                 // with a known key that can then be used to retrieve the object later on
-                $this->_model_relations[ $relation_name ][ $cache_id ] = $object_to_cache;
+                $this->_model_relations[$relation_name][$cache_id] = $object_to_cache;
                 $return                                                = $cache_id;
             } elseif ($object_to_cache->ID()) {
                 // OR the cached object originally came from the db, so let's just use it's PK for an ID
-                $this->_model_relations[ $relation_name ][ $object_to_cache->ID() ] = $object_to_cache;
+                $this->_model_relations[$relation_name][$object_to_cache->ID()] = $object_to_cache;
                 $return                                                             = $object_to_cache->ID();
             } else {
                 // OR it's a new object with no ID, so just throw it in the array with an auto-incremented ID
-                $this->_model_relations[ $relation_name ][] = $object_to_cache;
+                $this->_model_relations[$relation_name][] = $object_to_cache;
                 // move the internal pointer to the end of the array
-                end($this->_model_relations[ $relation_name ]);
+                end($this->_model_relations[$relation_name]);
                 // and grab the key so that we can return it
-                $return = key($this->_model_relations[ $relation_name ]);
+                $return = key($this->_model_relations[$relation_name]);
             }
         }
         return $return;
@@ -643,7 +643,7 @@ 
         $this->get_model()->field_settings_for($fieldname);
         $cache_type = empty($cache_type) ? 'standard' : $cache_type;
 
-        $this->_cached_properties[ $fieldname ][ $cache_type ] = $value;
+        $this->_cached_properties[$fieldname][$cache_type] = $value;
     }
 
 
@@ -672,9 +672,9 @@ 
         $model = $this->get_model();
         $model->field_settings_for($fieldname);
         $cache_type = $pretty ? 'pretty' : 'standard';
-        $cache_type .= ! empty($extra_cache_ref) ? '_' . $extra_cache_ref : '';
-        if (isset($this->_cached_properties[ $fieldname ][ $cache_type ])) {
-            return $this->_cached_properties[ $fieldname ][ $cache_type ];
+        $cache_type .= ! empty($extra_cache_ref) ? '_'.$extra_cache_ref : '';
+        if (isset($this->_cached_properties[$fieldname][$cache_type])) {
+            return $this->_cached_properties[$fieldname][$cache_type];
         }
         $value = $this->_get_fresh_property($fieldname, $pretty, $extra_cache_ref);
         $this->_set_cached_property($fieldname, $value, $cache_type);
@@ -702,12 +702,12 @@ 
         if ($field_obj instanceof EE_Datetime_Field) {
             $this->_prepare_datetime_field($field_obj, $pretty, $extra_cache_ref);
         }
-        if (! isset($this->_fields[ $fieldname ])) {
-            $this->_fields[ $fieldname ] = null;
+        if ( ! isset($this->_fields[$fieldname])) {
+            $this->_fields[$fieldname] = null;
         }
         return $pretty
-            ? $field_obj->prepare_for_pretty_echoing($this->_fields[ $fieldname ], $extra_cache_ref)
-            : $field_obj->prepare_for_get($this->_fields[ $fieldname ]);
+            ? $field_obj->prepare_for_pretty_echoing($this->_fields[$fieldname], $extra_cache_ref)
+            : $field_obj->prepare_for_get($this->_fields[$fieldname]);
     }
 
 
@@ -763,8 +763,8 @@ 
      */
     protected function _clear_cached_property($property_name)
     {
-        if (isset($this->_cached_properties[ $property_name ])) {
-            unset($this->_cached_properties[ $property_name ]);
+        if (isset($this->_cached_properties[$property_name])) {
+            unset($this->_cached_properties[$property_name]);
         }
     }
 
@@ -816,7 +816,7 @@ 
     {
         $relationship_to_model = $this->get_model()->related_settings_for($relation_name);
         $index_in_cache        = '';
-        if (! $relationship_to_model) {
+        if ( ! $relationship_to_model) {
             throw new EE_Error(
                 sprintf(
                     esc_html__('There is no relationship to %s on a %s. Cannot clear that cache', 'event_espresso'),
@@ -827,10 +827,10 @@ 
         }
         if ($clear_all) {
             $obj_removed                              = true;
-            $this->_model_relations[ $relation_name ] = null;
+            $this->_model_relations[$relation_name] = null;
         } elseif ($relationship_to_model instanceof EE_Belongs_To_Relation) {
-            $obj_removed                              = $this->_model_relations[ $relation_name ];
-            $this->_model_relations[ $relation_name ] = null;
+            $obj_removed                              = $this->_model_relations[$relation_name];
+            $this->_model_relations[$relation_name] = null;
         } else {
             if (
                 $object_to_remove_or_index_into_array instanceof EE_Base_Class
@@ -838,12 +838,12 @@ 
             ) {
                 $index_in_cache = $object_to_remove_or_index_into_array->ID();
                 if (
-                    is_array($this->_model_relations[ $relation_name ])
-                    && ! isset($this->_model_relations[ $relation_name ][ $index_in_cache ])
+                    is_array($this->_model_relations[$relation_name])
+                    && ! isset($this->_model_relations[$relation_name][$index_in_cache])
                 ) {
                     $index_found_at = null;
                     // find this object in the array even though it has a different key
-                    foreach ($this->_model_relations[ $relation_name ] as $index => $obj) {
+                    foreach ($this->_model_relations[$relation_name] as $index => $obj) {
                         /** @noinspection TypeUnsafeComparisonInspection */
                         if (
                             $obj instanceof EE_Base_Class
@@ -877,9 +877,9 @@ 
             }
             // supposedly we've found it. But it could just be that the client code
             // provided a bad index/object
-            if (isset($this->_model_relations[ $relation_name ][ $index_in_cache ])) {
-                $obj_removed = $this->_model_relations[ $relation_name ][ $index_in_cache ];
-                unset($this->_model_relations[ $relation_name ][ $index_in_cache ]);
+            if (isset($this->_model_relations[$relation_name][$index_in_cache])) {
+                $obj_removed = $this->_model_relations[$relation_name][$index_in_cache];
+                unset($this->_model_relations[$relation_name][$index_in_cache]);
             } else {
                 // that thing was never cached anyways.
                 $obj_removed = null;
@@ -910,7 +910,7 @@ 
         $current_cache_id = ''
     ) {
         // verify that incoming object is of the correct type
-        $obj_class = 'EE_' . $relation_name;
+        $obj_class = 'EE_'.$relation_name;
         if ($newly_saved_object instanceof $obj_class) {
             /* @type EE_Base_Class $newly_saved_object */
             // now get the type of relation
@@ -918,18 +918,18 @@ 
             // if this is a 1:1 relationship
             if ($relationship_to_model instanceof EE_Belongs_To_Relation) {
                 // then just replace the cached object with the newly saved object
-                $this->_model_relations[ $relation_name ] = $newly_saved_object;
+                $this->_model_relations[$relation_name] = $newly_saved_object;
                 return true;
                 // or if it's some kind of sordid feral polyamorous relationship...
             }
             if (
-                is_array($this->_model_relations[ $relation_name ])
-                && isset($this->_model_relations[ $relation_name ][ $current_cache_id ])
+                is_array($this->_model_relations[$relation_name])
+                && isset($this->_model_relations[$relation_name][$current_cache_id])
             ) {
                 // then remove the current cached item
-                unset($this->_model_relations[ $relation_name ][ $current_cache_id ]);
+                unset($this->_model_relations[$relation_name][$current_cache_id]);
                 // and cache the newly saved object using it's new ID
-                $this->_model_relations[ $relation_name ][ $newly_saved_object->ID() ] = $newly_saved_object;
+                $this->_model_relations[$relation_name][$newly_saved_object->ID()] = $newly_saved_object;
                 return true;
             }
         }
@@ -946,7 +946,7 @@ 
      */
     public function get_one_from_cache($relation_name)
     {
-        $cached_array_or_object = $this->_model_relations[ $relation_name ] ?? null;
+        $cached_array_or_object = $this->_model_relations[$relation_name] ?? null;
         if (is_array($cached_array_or_object)) {
             return array_shift($cached_array_or_object);
         }
@@ -968,7 +968,7 @@ 
      */
     public function get_all_from_cache($relation_name)
     {
-        $objects = $this->_model_relations[ $relation_name ] ?? [];
+        $objects = $this->_model_relations[$relation_name] ?? [];
         // if the result is not an array, but exists, make it an array
         $objects = is_array($objects)
             ? $objects
@@ -1160,9 +1160,9 @@ 
     public function get_raw($field_name)
     {
         $field_settings = $this->get_model()->field_settings_for($field_name);
-        return $field_settings instanceof EE_Datetime_Field && $this->_fields[ $field_name ] instanceof DateTime
-            ? $this->_fields[ $field_name ]->format('U')
-            : $this->_fields[ $field_name ];
+        return $field_settings instanceof EE_Datetime_Field && $this->_fields[$field_name] instanceof DateTime
+            ? $this->_fields[$field_name]->format('U')
+            : $this->_fields[$field_name];
     }
 
 
@@ -1184,7 +1184,7 @@ 
     public function get_DateTime_object($field_name)
     {
         $field_settings = $this->get_model()->field_settings_for($field_name);
-        if (! $field_settings instanceof EE_Datetime_Field) {
+        if ( ! $field_settings instanceof EE_Datetime_Field) {
             EE_Error::add_error(
                 sprintf(
                     esc_html__(
@@ -1199,8 +1199,8 @@ 
             );
             return false;
         }
-        return isset($this->_fields[ $field_name ]) && $this->_fields[ $field_name ] instanceof DateTime
-            ? clone $this->_fields[ $field_name ]
+        return isset($this->_fields[$field_name]) && $this->_fields[$field_name] instanceof DateTime
+            ? clone $this->_fields[$field_name]
             : null;
     }
 
@@ -1445,7 +1445,7 @@ 
      */
     public function get_i18n_datetime(string $field_name, string $format = ''): string
     {
-        $format = empty($format) ? $this->_dt_frmt . ' ' . $this->_tm_frmt : $format;
+        $format = empty($format) ? $this->_dt_frmt.' '.$this->_tm_frmt : $format;
         return date_i18n(
             $format,
             EEH_DTT_Helper::get_timestamp_with_offset(
@@ -1557,21 +1557,21 @@ 
         $field->set_time_format($this->_tm_frmt);
         switch ($what) {
             case 'T':
-                $this->_fields[ $field_name ] = $field->prepare_for_set_with_new_time(
+                $this->_fields[$field_name] = $field->prepare_for_set_with_new_time(
                     $datetime_value,
-                    $this->_fields[ $field_name ]
+                    $this->_fields[$field_name]
                 );
                 $this->_has_changes           = true;
                 break;
             case 'D':
-                $this->_fields[ $field_name ] = $field->prepare_for_set_with_new_date(
+                $this->_fields[$field_name] = $field->prepare_for_set_with_new_date(
                     $datetime_value,
-                    $this->_fields[ $field_name ]
+                    $this->_fields[$field_name]
                 );
                 $this->_has_changes           = true;
                 break;
             case 'B':
-                $this->_fields[ $field_name ] = $field->prepare_for_set($datetime_value);
+                $this->_fields[$field_name] = $field->prepare_for_set($datetime_value);
                 $this->_has_changes           = true;
                 break;
         }
@@ -1614,7 +1614,7 @@ 
         $this->set_timezone($timezone);
         $fn   = (array) $field_name;
         $args = array_merge($fn, (array) $args);
-        if (! method_exists($this, $callback)) {
+        if ( ! method_exists($this, $callback)) {
             throw new EE_Error(
                 sprintf(
                     esc_html__(
@@ -1626,7 +1626,7 @@ 
             );
         }
         $args   = (array) $args;
-        $return = $prepend . call_user_func_array([$this, $callback], $args) . $append;
+        $return = $prepend.call_user_func_array([$this, $callback], $args).$append;
         $this->set_timezone($original_timezone);
         return $return;
     }
@@ -1741,8 +1741,8 @@ 
     {
         $model = $this->get_model();
         foreach ($model->relation_settings() as $relation_name => $relation_obj) {
-            if (! empty($this->_model_relations[ $relation_name ])) {
-                $related_objects = $this->_model_relations[ $relation_name ];
+            if ( ! empty($this->_model_relations[$relation_name])) {
+                $related_objects = $this->_model_relations[$relation_name];
                 if ($relation_obj instanceof EE_Belongs_To_Relation) {
                     // this relation only stores a single model object, not an array
                     // but let's make it consistent
@@ -1799,7 +1799,7 @@ 
             $this->set($column, $value);
         }
         // no changes ? then don't do anything
-        if (! $this->_has_changes && $this->ID() && $model->get_primary_key_field()->is_auto_increment()) {
+        if ( ! $this->_has_changes && $this->ID() && $model->get_primary_key_field()->is_auto_increment()) {
             return 0;
         }
         /**
@@ -1809,7 +1809,7 @@ 
          * @param EE_Base_Class $model_object the model object about to be saved.
          */
         do_action('AHEE__EE_Base_Class__save__begin', $this);
-        if (! $this->allow_persist()) {
+        if ( ! $this->allow_persist()) {
             return 0;
         }
         // now get current attribute values
@@ -1824,10 +1824,10 @@ 
         if ($model->has_primary_key_field()) {
             if ($model->get_primary_key_field()->is_auto_increment()) {
                 // ok check if it's set, if so: update; if not, insert
-                if (! empty($save_cols_n_values[ $model->primary_key_name() ])) {
+                if ( ! empty($save_cols_n_values[$model->primary_key_name()])) {
                     $results = $model->update_by_ID($save_cols_n_values, $this->ID());
                 } else {
-                    unset($save_cols_n_values[ $model->primary_key_name() ]);
+                    unset($save_cols_n_values[$model->primary_key_name()]);
                     $results = $model->insert($save_cols_n_values);
                     if ($results) {
                         // if successful, set the primary key
@@ -1837,7 +1837,7 @@ 
                         // will get added to the mapper before we can add this one!
                         // but if we just avoid using the SET method, all that headache can be avoided
                         $pk_field_name                   = $model->primary_key_name();
-                        $this->_fields[ $pk_field_name ] = $results;
+                        $this->_fields[$pk_field_name] = $results;
                         $this->_clear_cached_property($pk_field_name);
                         $model->add_to_entity_map($this);
                         $this->_update_cached_related_model_objs_fks();
@@ -1854,8 +1854,8 @@ 
                                     'event_espresso'
                                 ),
                                 get_class($this),
-                                get_class($model) . '::instance()->add_to_entity_map()',
-                                get_class($model) . '::instance()->get_one_by_ID()',
+                                get_class($model).'::instance()->add_to_entity_map()',
+                                get_class($model).'::instance()->get_one_by_ID()',
                                 '<br />'
                             )
                         );
@@ -1879,7 +1879,7 @@ 
                     $save_cols_n_values,
                     $model->get_combined_primary_key_fields()
                 );
-                $results                     = $model->update(
+                $results = $model->update(
                     $save_cols_n_values,
                     $combined_pk_fields_n_values
                 );
@@ -1957,27 +1957,27 @@ 
     public function save_new_cached_related_model_objs()
     {
         // make sure this has been saved
-        if (! $this->ID()) {
+        if ( ! $this->ID()) {
             $id = $this->save();
         } else {
             $id = $this->ID();
         }
         // now save all the NEW cached model objects  (ie they don't exist in the DB)
         foreach ($this->get_model()->relation_settings() as $relation_name => $relationObj) {
-            if ($this->_model_relations[ $relation_name ]) {
+            if ($this->_model_relations[$relation_name]) {
                 // is this a relation where we should expect just ONE related object (ie, EE_Belongs_To_relation)
                 // or MANY related objects (ie, EE_HABTM_Relation or EE_Has_Many_Relation)?
                 /* @var $related_model_obj EE_Base_Class */
                 if ($relationObj instanceof EE_Belongs_To_Relation) {
                     // add a relation to that relation type (which saves the appropriate thing in the process)
                     // but ONLY if it DOES NOT exist in the DB
-                    $related_model_obj = $this->_model_relations[ $relation_name ];
+                    $related_model_obj = $this->_model_relations[$relation_name];
                     // if( ! $related_model_obj->ID()){
                     $this->_add_relation_to($related_model_obj, $relation_name);
                     $related_model_obj->save_new_cached_related_model_objs();
                     // }
                 } else {
-                    foreach ($this->_model_relations[ $relation_name ] as $related_model_obj) {
+                    foreach ($this->_model_relations[$relation_name] as $related_model_obj) {
                         // add a relation to that relation type (which saves the appropriate thing in the process)
                         // but ONLY if it DOES NOT exist in the DB
                         // if( ! $related_model_obj->ID()){
@@ -2004,7 +2004,7 @@ 
      */
     public function get_model()
     {
-        if (! $this->_model) {
+        if ( ! $this->_model) {
             $modelName    = self::_get_model_classname(get_class($this));
             $this->_model = self::_get_model_instance_with_name($modelName, $this->_timezone);
         } else {
@@ -2030,9 +2030,9 @@ 
         $primary_id_ref = self::_get_primary_key_name($classname);
         if (
             array_key_exists($primary_id_ref, $props_n_values)
-            && ! empty($props_n_values[ $primary_id_ref ])
+            && ! empty($props_n_values[$primary_id_ref])
         ) {
-            $id = $props_n_values[ $primary_id_ref ];
+            $id = $props_n_values[$primary_id_ref];
             return self::_get_model($classname)->get_from_entity_map($id);
         }
         return false;
@@ -2065,10 +2065,10 @@ 
             $primary_id_ref = self::_get_primary_key_name($classname);
             if (
                 array_key_exists($primary_id_ref, $props_n_values)
-                && ! empty($props_n_values[ $primary_id_ref ])
+                && ! empty($props_n_values[$primary_id_ref])
             ) {
                 $existing = $model->get_one_by_ID(
-                    $props_n_values[ $primary_id_ref ]
+                    $props_n_values[$primary_id_ref]
                 );
             }
         } elseif ($model->has_all_combined_primary_key_fields($props_n_values)) {
@@ -2080,7 +2080,7 @@ 
         }
         if ($existing) {
             // set date formats if present before setting values
-            if (! empty($date_formats) && is_array($date_formats)) {
+            if ( ! empty($date_formats) && is_array($date_formats)) {
                 $existing->set_date_format($date_formats[0]);
                 $existing->set_time_format($date_formats[1]);
             } else {
@@ -2113,7 +2113,7 @@ 
     protected static function _get_model($classname, $timezone = '')
     {
         // find model for this class
-        if (! $classname) {
+        if ( ! $classname) {
             throw new EE_Error(
                 sprintf(
                     esc_html__(
@@ -2161,7 +2161,7 @@ 
     {
         return strpos((string) $model_name, 'EE_') === 0
             ? str_replace('EE_', 'EEM_', $model_name)
-            : 'EEM_' . $model_name;
+            : 'EEM_'.$model_name;
     }
 
 
@@ -2178,7 +2178,7 @@ 
      */
     protected static function _get_primary_key_name($classname = null)
     {
-        if (! $classname) {
+        if ( ! $classname) {
             throw new EE_Error(
                 sprintf(
                     esc_html__('What were you thinking calling _get_primary_key_name(%s)', 'event_espresso'),
@@ -2208,7 +2208,7 @@ 
         $model = $this->get_model();
         // now that we know the name of the variable, use a variable variable to get its value and return its
         if ($model->has_primary_key_field()) {
-            return $this->_fields[ $model->primary_key_name() ];
+            return $this->_fields[$model->primary_key_name()];
         }
         return $model->get_index_primary_key_string($this->_fields);
     }
@@ -2282,7 +2282,7 @@ 
             }
         } else {
             // this thing doesn't exist in the DB,  so just cache it
-            if (! $otherObjectModelObjectOrID instanceof EE_Base_Class) {
+            if ( ! $otherObjectModelObjectOrID instanceof EE_Base_Class) {
                 throw new EE_Error(
                     sprintf(
                         esc_html__(
@@ -2449,7 +2449,7 @@ 
             } else {
                 // did we already cache the result of this query?
                 $cached_results = $this->get_all_from_cache($relation_name);
-                if (! $cached_results) {
+                if ( ! $cached_results) {
                     $related_model_objects = $this->get_model()->get_all_related(
                         $this,
                         $relation_name,
@@ -2561,7 +2561,7 @@ 
             } else {
                 // first, check if we've already cached the result of this query
                 $cached_result = $this->get_one_from_cache($relation_name);
-                if (! $cached_result) {
+                if ( ! $cached_result) {
                     $related_model_object = $model->get_first_related(
                         $this,
                         $relation_name,
@@ -2585,7 +2585,7 @@ 
             }
             // this doesn't exist in the DB and apparently the thing it belongs to doesn't either,
             // just get what's cached on this object
-            if (! $related_model_object) {
+            if ( ! $related_model_object) {
                 $related_model_object = $this->get_one_from_cache($relation_name);
             }
         }
@@ -2668,7 +2668,7 @@ 
      */
     public function is_set($field_name)
     {
-        return isset($this->_fields[ $field_name ]);
+        return isset($this->_fields[$field_name]);
     }
 
 
@@ -2684,7 +2684,7 @@ 
     {
         foreach ((array) $properties as $property_name) {
             // first make sure this property exists
-            if (! $this->_fields[ $property_name ]) {
+            if ( ! $this->_fields[$property_name]) {
                 throw new EE_Error(
                     sprintf(
                         esc_html__(
@@ -2716,7 +2716,7 @@ 
         $properties = [];
         // remove prepended underscore
         foreach ($fields as $field_name => $settings) {
-            $properties[ $field_name ] = $this->get($field_name);
+            $properties[$field_name] = $this->get($field_name);
         }
         return $properties;
     }
@@ -2753,7 +2753,7 @@ 
     {
         $className = get_class($this);
         $tagName   = "FHEE__{$className}__{$methodName}";
-        if (! has_filter($tagName)) {
+        if ( ! has_filter($tagName)) {
             throw new EE_Error(
                 sprintf(
                     esc_html__(
@@ -2798,7 +2798,7 @@ 
             $query_params[0]['EXM_value'] = $meta_value;
         }
         $existing_rows_like_that = EEM_Extra_Meta::instance()->get_all($query_params);
-        if (! $existing_rows_like_that) {
+        if ( ! $existing_rows_like_that) {
             return $this->add_extra_meta($meta_key, $meta_value);
         }
         foreach ($existing_rows_like_that as $existing_row) {
@@ -2908,7 +2908,7 @@ 
                 $values = [];
                 foreach ($results as $result) {
                     if ($result instanceof EE_Extra_Meta) {
-                        $values[ $result->ID() ] = $result->value();
+                        $values[$result->ID()] = $result->value();
                     }
                 }
                 return $values;
@@ -2953,17 +2953,17 @@ 
             );
             foreach ($extra_meta_objs as $extra_meta_obj) {
                 if ($extra_meta_obj instanceof EE_Extra_Meta) {
-                    $return_array[ $extra_meta_obj->key() ] = $extra_meta_obj->value();
+                    $return_array[$extra_meta_obj->key()] = $extra_meta_obj->value();
                 }
             }
         } else {
             $extra_meta_objs = $this->get_many_related('Extra_Meta');
             foreach ($extra_meta_objs as $extra_meta_obj) {
                 if ($extra_meta_obj instanceof EE_Extra_Meta) {
-                    if (! isset($return_array[ $extra_meta_obj->key() ])) {
-                        $return_array[ $extra_meta_obj->key() ] = [];
+                    if ( ! isset($return_array[$extra_meta_obj->key()])) {
+                        $return_array[$extra_meta_obj->key()] = [];
                     }
-                    $return_array[ $extra_meta_obj->key() ][ $extra_meta_obj->ID() ] = $extra_meta_obj->value();
+                    $return_array[$extra_meta_obj->key()][$extra_meta_obj->ID()] = $extra_meta_obj->value();
                 }
             }
         }
@@ -3044,8 +3044,8 @@ 
                             'event_espresso'
                         ),
                         $this->ID(),
-                        get_class($this->get_model()) . '::instance()->add_to_entity_map()',
-                        get_class($this->get_model()) . '::instance()->refresh_entity_map()'
+                        get_class($this->get_model()).'::instance()->add_to_entity_map()',
+                        get_class($this->get_model()).'::instance()->refresh_entity_map()'
                     )
                 );
             }
@@ -3078,7 +3078,7 @@ 
     {
         // First make sure this model object actually exists in the DB. It would be silly to try to update it in the DB
         // if it wasn't even there to start off.
-        if (! $this->ID()) {
+        if ( ! $this->ID()) {
             $this->save();
         }
         global $wpdb;
@@ -3118,7 +3118,7 @@ 
             $table_pk_field_name = $table_obj->get_pk_column();
         }
 
-        $query  =
+        $query =
             "UPDATE `{$table_name}`
             SET "
             . $new_value_sql
@@ -3312,7 +3312,7 @@ 
         $model = $this->get_model();
         foreach ($model->relation_settings() as $relation_name => $relation_obj) {
             if ($relation_obj instanceof EE_Belongs_To_Relation) {
-                $classname = 'EE_' . $model->get_this_model_name();
+                $classname = 'EE_'.$model->get_this_model_name();
                 if (
                     $this->get_one_from_cache($relation_name) instanceof $classname
                     && $this->get_one_from_cache($relation_name)->ID()
@@ -3353,7 +3353,7 @@ 
         // handle DateTimes (this is handled in here because there's no one specific child class that uses datetimes).
         foreach ($this->_fields as $field => $value) {
             if ($value instanceof DateTime) {
-                $this->_fields[ $field ] = clone $value;
+                $this->_fields[$field] = clone $value;
             }
         }
     }
@@ -3368,7 +3368,7 @@ 
 
     private function echoProperty($field, $value, int $indent = 0)
     {
-        $bullets = str_repeat(' -', $indent) . ' ';
+        $bullets = str_repeat(' -', $indent).' ';
         $field = strpos($field, '_') === 0 ? substr($field, 1) : $field;
         echo "\n$bullets$field: ";
         if ($value instanceof EEM_Base) {
@@ -3377,8 +3377,8 @@ 
             $value = get_object_vars($value);
         }
         if (is_array($value)) {
-            foreach ($value as $f => $v ) {
-                $this->echoProperty($f, $v, $indent+1);
+            foreach ($value as $f => $v) {
+                $this->echoProperty($f, $v, $indent + 1);
             }
             return;
         }

core/db_classes/EE_Registration_Payment.class.php

Indentation +81 added lines, -81 removed lines

@@ -12,99 +12,99 @@
  */
 class EE_Registration_Payment extends EE_Base_Class
 {
-    /**
-     * @param array  $props_n_values
-     * @param string $timezone
-     * @param array  $date_formats
-     * @return EE_Registration_Payment
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public static function new_instance($props_n_values = [], $timezone = '', $date_formats = [])
-    {
-        $has_object = parent::_check_for_object($props_n_values, __CLASS__, $timezone, $date_formats);
-        return $has_object ?: new self($props_n_values, false, $timezone, $date_formats);
-    }
+	/**
+	 * @param array  $props_n_values
+	 * @param string $timezone
+	 * @param array  $date_formats
+	 * @return EE_Registration_Payment
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public static function new_instance($props_n_values = [], $timezone = '', $date_formats = [])
+	{
+		$has_object = parent::_check_for_object($props_n_values, __CLASS__, $timezone, $date_formats);
+		return $has_object ?: new self($props_n_values, false, $timezone, $date_formats);
+	}
 
 
-    /**
-     * @param array  $props_n_values
-     * @param string $timezone
-     * @return EE_Registration_Payment
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public static function new_instance_from_db($props_n_values = [], $timezone = '')
-    {
-        return new self($props_n_values, true, $timezone);
-    }
+	/**
+	 * @param array  $props_n_values
+	 * @param string $timezone
+	 * @return EE_Registration_Payment
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public static function new_instance_from_db($props_n_values = [], $timezone = '')
+	{
+		return new self($props_n_values, true, $timezone);
+	}
 
 
-    /**
-     * @return    int
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function registration_ID(): int
-    {
-        return (int) $this->get('REG_ID');
-    }
+	/**
+	 * @return    int
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function registration_ID(): int
+	{
+		return (int) $this->get('REG_ID');
+	}
 
 
-    /**
-     * @return    int
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function payment_ID(): int
-    {
-        return (int) $this->get('PAY_ID');
-    }
+	/**
+	 * @return    int
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function payment_ID(): int
+	{
+		return (int) $this->get('PAY_ID');
+	}
 
 
-    /**
-     * amount
-     *
-     * @access    public
-     * @return    float
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function amount(): float
-    {
-        return (float) $this->get('RPY_amount');
-    }
+	/**
+	 * amount
+	 *
+	 * @access    public
+	 * @return    float
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function amount(): float
+	{
+		return (float) $this->get('RPY_amount');
+	}
 
 
-    /**
-     * @param float|int|string $amount
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function set_amount($amount = 0.000)
-    {
-        $this->set('RPY_amount', (float) $amount);
-    }
+	/**
+	 * @param float|int|string $amount
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function set_amount($amount = 0.000)
+	{
+		$this->set('RPY_amount', (float) $amount);
+	}
 
 
-    /**
-     * @return EE_Registration|null
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function registration(): ?EE_Registration
-    {
-        return $this->get_first_related('Registration');
-    }
+	/**
+	 * @return EE_Registration|null
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function registration(): ?EE_Registration
+	{
+		return $this->get_first_related('Registration');
+	}
 
 
-    /**
-     * @return EE_Payment|null
-     * @throws EE_Error
-     * @throws ReflectionException
-     */
-    public function payment(): ?EE_Payment
-    {
-        return $this->get_first_related('Payment');
-    }
+	/**
+	 * @return EE_Payment|null
+	 * @throws EE_Error
+	 * @throws ReflectionException
+	 */
+	public function payment(): ?EE_Payment
+	{
+		return $this->get_first_related('Payment');
+	}
 }