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<?php |
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namespace vijinho\Enums; |
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/** |
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* Abstract class for implementing ENUMs in PHP7 |
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* |
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* @author Vijay Mahrra <[email protected]> |
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* @copyright (c) Copyright 2016 Vijay Mahrra |
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* @license GPLv3 (http://www.gnu.org/licenses/gpl-3.0.html) |
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* @link http://php.net/manual/en/class.serializable.php |
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* @link http://php.net/manual/en/class.arrayaccess.php |
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*/ |
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class Enum implements \Serializable, \ArrayAccess |
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{ |
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/** |
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* base enum values |
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* |
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* @var array $values |
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*/ |
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protected static $values = []; |
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/** |
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* allow keys to be unset/deleted? |
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* cannot be over-ridden once defined in a class |
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* |
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* @var boolean |
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*/ |
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protected static $delete = false; |
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/** |
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* allow keys to be over-written when adding? |
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* cannot be over-ridden once defined in a class |
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* |
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* @var boolean |
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*/ |
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protected static $overwrite = false; |
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/** |
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* always capitalize enum keys? |
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* can be over-ridden once defined in a class |
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* with capitalize(boolean) method |
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* |
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* @var boolean |
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*/ |
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protected static $capitalize = false; |
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/** |
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* case-sensitive check when searching by key for a value? |
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* can be over-ridden once defined in a class |
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* with caseSensitive(boolean) method |
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* |
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* @var boolean |
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*/ |
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protected static $caseSensitive = false; |
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/** |
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* initialize with array of additional values not existing already |
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* |
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* @param array static::$values |
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*/ |
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public function __construct(array $newValues = []) |
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{ |
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static::fixKeys(); |
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static::add($newValues); |
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} |
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/** |
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* Set case-sensitivity when searching |
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* |
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* @param boolean $bool |
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*/ |
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public static function caseSensitive($bool = false) |
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{ |
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static::$caseSensitive = !empty($bool); |
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} |
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/** |
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* Set capitalization for enum keys |
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* |
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* @param boolean $bool |
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*/ |
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public static function capitalize($bool = false) |
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{ |
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static::$capitalize = !empty($bool); |
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if (static::$capitalize) { |
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static::$values = array_change_key_case(static::$values, CASE_UPPER); |
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} |
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} |
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/** |
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* Clear all data - use with care! |
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* |
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* @param boolean $caseSensitive |
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* @param boolean $capitalize |
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*/ |
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public static function reset($caseSensitive = false, $capitalize = false) |
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{ |
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static::$values = []; |
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static::$caseSensitive = $caseSensitive; |
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static::$capitalize = $capitalize; |
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} |
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/** |
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* Remove an enum value - use with care! |
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* |
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*/ |
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public static function delete($key) |
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{ |
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$allowed = !empty(static::$delete); |
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if (empty($allowed)) { |
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throw new \LogicException('Method not allowed.'); |
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} |
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$values = & static::$values; |
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if (array_key_exists($key, $values)) { |
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unset($values[$key]); |
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} else { |
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return false; |
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} |
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return true; |
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} |
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/** |
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* Make sure that the enum keys have no SPACEs |
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* Make sure the keys are strings |
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* Set the case according to the settings |
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* |
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* @param return array static::$values |
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*/ |
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public static function fixKeys(): array |
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{ |
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$values = static::$values; |
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foreach ($values as $k => $v) { |
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unset($values[$k]); |
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if (!is_string($k)) { |
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if (!is_string($v)) { |
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throw new \UnexpectedValueException(sprintf("Key '%s' for value '%s' is not a string!", print_r($k, 1), print_r($v, 1))); |
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} else { |
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// if the key is not a string, use the value if it is a string |
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$k = $v; |
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} |
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} |
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$k = str_replace(' ', '_', $k); // space converted for magic calls |
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$values[$k] = $v; |
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} |
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static::$values = empty(static::$capitalize) ? |
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$values : array_change_key_case($values, CASE_UPPER); |
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return static::$values; |
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} |
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/** |
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* add array of extra values not existing already |
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* |
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* @param array|string $newValues |
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* @param null|boolean $overwrite allow over-write of values? |
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* @return array static::$values |
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*/ |
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public static function add($newValues, $overwrite = null): array |
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{ |
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if (empty(static::$overwrite) && !empty($overwrite)) { |
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throw new \LogicException('Overwrite not allowed.'); |
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} |
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$values = & static::$values; |
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// if it's a string, convert to array |
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if (is_string($newValues)) { |
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$newValues = [$newValues => $newValues]; |
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} |
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foreach ($newValues as $k => $v) { |
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$overwrite = (null == $overwrite) ? static::$overwrite : $overwrite; |
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if (!empty($overwrite)) { |
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$values[$k] = $v; |
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} elseif (!array_key_exists($k, $values)) { |
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$values[$k] = $v; |
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} |
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} |
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return static::fixKeys(); |
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} |
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/** |
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* get array of keys |
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* |
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* @return array keys of static::$values |
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*/ |
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public static function keys(): array |
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{ |
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return array_keys(static::$values); |
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} |
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/** |
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* get key for the given value |
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* |
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* @param mixed $value |
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* @param null|bool $caseSensitive search is case sensitive? |
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* @return string|array key(s) |
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*/ |
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public static function key($value, $caseSensitive = null) |
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{ |
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$values = static::$values; |
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if (!is_array($value) && !is_object($value)) { |
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if (is_string($value)) { |
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$value = strtoupper($value); |
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// if case-sensitivity is not specified use the class boolean value |
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if (null === $caseSensitive) { |
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$caseSensitive = static::$caseSensitive; |
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} |
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if (empty($caseSensitive)) { |
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$values = array_map(function($value) { |
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return strtoupper($value); |
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}, $values); |
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} |
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} |
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$keys = array_keys($values, $value); |
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$count = count($keys); |
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if (0 === $count) { |
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throw new \InvalidArgumentException(sprintf("Key for value '%s' does not exist.", print_r($value, 1))); |
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} |
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return count($keys) > 1 ? $keys : $keys[0]; |
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} elseif (is_array($value)) { |
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$search = array_search($value, $values); |
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if (false === $search) { |
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throw new \InvalidArgumentException(sprintf("Key for value '%s' does not exist.", print_r($value, 1))); |
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} |
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return $search; |
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} |
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} |
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/** |
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* count values |
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* |
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* @return int number of values |
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*/ |
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public static function count(): int |
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{ |
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return count(static::$values); |
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} |
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/** |
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* count values |
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* |
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* @return int number of values |
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*/ |
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public static function sizeof(): int |
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{ |
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return static::count(); |
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} |
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/** |
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* get existing values |
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* |
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* @return array static::$values |
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*/ |
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public static function values(): array |
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{ |
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return static::$values; |
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} |
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/** |
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* get value for the given key |
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* |
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* @param string $key |
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* @param null|bool $caseSensitive search is case sensitive? |
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* @return mixed static::$values[$key] |
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*/ |
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public static function value($key, $caseSensitive = null) |
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{ |
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$values = static::$values; |
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// if case-sensitivity is not specified use the class boolean value |
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3 |
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if (null === $caseSensitive) { |
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$caseSensitive = static::$caseSensitive; |
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} |
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3 |
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if (empty($caseSensitive)) { |
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$key = strtoupper($key); |
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$values = array_change_key_case($values, CASE_UPPER); |
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} |
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3 |
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if (false === array_key_exists($key, $values)) { |
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throw new \InvalidArgumentException(sprintf("Value for key '%s' does not exist.", print_r($key, 1))); |
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} |
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return $values[$key]; |
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} |
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/** |
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* get value for the given key |
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* method allows getting value from an object with $object->key |
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* |
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* @return mixed static::$values[$key] |
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* @link http://php.net/manual/en/language.oop5.overloading.php#object.get |
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*/ |
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public function __get(string $key) { |
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return static::value($key); |
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} |
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/** |
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* get value named the same as the method called |
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* method allows getting value from an object with $object->key() |
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* |
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* @param string $key the method called is used as the key |
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* @param array $args |
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* @return mixed static::$values[$key] |
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* @link http://php.net/manual/en/language.oop5.overloading.php#object.call |
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*/ |
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1 |
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public function __call(string $key, array $args = []) { |
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1 |
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return static::value($key); |
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} |
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326
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/** |
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327
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* get value named the same as the method called statically |
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328
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* method allows getting value from an object with $object::key() |
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* |
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* @param string $key the method called is used as the key |
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* @param array $args |
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* @return mixed static::$values[$key] |
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* @link http://php.net/manual/en/language.oop5.overloading.php#object.callstatic |
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334
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*/ |
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335
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public static function __callStatic(string $key, array $args = []) { |
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336
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return static::value($key); |
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337
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} |
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338
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|
339
|
|
|
|
|
340
|
|
|
/** |
|
341
|
|
|
* check if the given key exists via call to $object of isset($object->key) |
|
342
|
|
|
* |
|
343
|
|
|
* @param string $key |
|
344
|
|
|
* @return boolean |
|
345
|
|
|
* @link http://php.net/manual/en/language.oop5.overloading.php#object.isset |
|
346
|
|
|
*/ |
|
347
|
1 |
|
public function __isset($key) |
|
348
|
|
|
{ |
|
349
|
1 |
|
return empty(static::$caseSensitive) ? |
|
350
|
1 |
|
array_key_exists(strtoupper($key), array_change_key_case(static::$values, CASE_UPPER)) : array_key_exists($key, static::$values); |
|
351
|
|
|
} |
|
352
|
|
|
|
|
353
|
|
|
|
|
354
|
|
|
/** |
|
355
|
|
|
* when called as a function this class will add new values and return the result |
|
356
|
|
|
* |
|
357
|
|
|
* @param array $newValues |
|
358
|
|
|
* @return boolean |
|
|
|
|
|
|
359
|
|
|
* @link http://php.net/manual/en/language.oop5.overloading.php#object.invoke |
|
360
|
|
|
*/ |
|
361
|
1 |
|
public function __invoke($newValues) |
|
362
|
|
|
{ |
|
363
|
1 |
|
return static::add($newValues); |
|
364
|
|
|
} |
|
365
|
|
|
|
|
366
|
|
|
|
|
367
|
|
|
/** |
|
368
|
|
|
* return the values as a string |
|
369
|
|
|
* method allows outputting values as a string |
|
370
|
|
|
* |
|
371
|
|
|
* @return string json_encode(static::$values) |
|
372
|
|
|
* @link http://php.net/manual/en/language.oop5.magic.php#object.tostring |
|
373
|
|
|
*/ |
|
374
|
1 |
|
public function __toString(): string |
|
375
|
|
|
{ |
|
376
|
1 |
|
return json_encode(static::$values, JSON_PRETTY_PRINT); |
|
377
|
|
|
} |
|
378
|
|
|
|
|
379
|
|
|
|
|
380
|
|
|
/** |
|
381
|
|
|
* return the values as a string |
|
382
|
|
|
* method allows outputting values as a string when called statically |
|
383
|
|
|
* |
|
384
|
|
|
* @return string json_encode(static::$values) |
|
385
|
|
|
*/ |
|
386
|
|
|
public static function toString(): string |
|
387
|
|
|
{ |
|
388
|
|
|
return json_encode(static::$values, JSON_PRETTY_PRINT); |
|
389
|
|
|
} |
|
390
|
|
|
|
|
391
|
|
|
|
|
392
|
|
|
/** |
|
393
|
|
|
* serialize enum values |
|
394
|
|
|
* |
|
395
|
|
|
* @return string enum values serialized |
|
396
|
|
|
* @link http://php.net/manual/en/class.serializable.php |
|
397
|
|
|
*/ |
|
398
|
1 |
|
public function serialize(): string |
|
399
|
|
|
{ |
|
400
|
1 |
|
return serialize(static::$values); |
|
401
|
|
|
} |
|
402
|
|
|
|
|
403
|
|
|
/** |
|
404
|
|
|
* unserialize serialized values to object |
|
405
|
|
|
* |
|
406
|
|
|
* @return string enum values serialized |
|
407
|
|
|
* @link http://php.net/manual/en/class.serializable.php |
|
408
|
|
|
* @return void |
|
409
|
|
|
*/ |
|
410
|
1 |
|
public function unserialize($data) { |
|
411
|
1 |
|
$data = unserialize($data); |
|
412
|
1 |
|
static::$values = $data; |
|
413
|
1 |
|
} |
|
414
|
|
|
|
|
415
|
|
|
|
|
416
|
|
|
/** |
|
417
|
|
|
* returned dump values as array |
|
418
|
|
|
* |
|
419
|
|
|
* @return array |
|
420
|
|
|
*/ |
|
421
|
|
|
public static function var_dump(): array |
|
422
|
|
|
{ |
|
423
|
|
|
$delete = static::$delete; |
|
424
|
|
|
$overwrite = static::$overwrite; |
|
425
|
|
|
$capitalize = static::$capitalize; |
|
426
|
|
|
$caseSensitive = static::$caseSensitive; |
|
427
|
|
|
$values = static::$values; |
|
428
|
|
|
return [ |
|
429
|
|
|
'overwrite' => $overwrite, |
|
430
|
|
|
'delete' => $delete, |
|
431
|
|
|
'capitalise' => $capitalize, |
|
432
|
|
|
'caseSensitive' => $caseSensitive, |
|
433
|
|
|
'values' => $values |
|
434
|
|
|
]; |
|
435
|
|
|
} |
|
436
|
|
|
|
|
437
|
|
|
|
|
438
|
|
|
/** |
|
439
|
|
|
* returned values when called with var_dump() |
|
440
|
|
|
* |
|
441
|
|
|
* @return array debug info |
|
442
|
|
|
* @link http://php.net/manual/en/language.oop5.magic.php#object.debuginfo |
|
443
|
|
|
*/ |
|
444
|
|
|
public function __debugInfo(): array |
|
445
|
|
|
{ |
|
446
|
|
|
return static::var_dump(); |
|
447
|
|
|
} |
|
448
|
|
|
|
|
449
|
|
|
/** |
|
450
|
|
|
* Implement Array offsetSet |
|
451
|
|
|
* |
|
452
|
|
|
* @param string $key the key to set |
|
453
|
|
|
* @param mixed $value the value to set |
|
454
|
|
|
* @return array debug info |
|
|
|
|
|
|
455
|
|
|
* @link http://php.net/manual/en/class.arrayaccess.php |
|
456
|
|
|
*/ |
|
457
|
|
|
public function offsetSet($key, $value) { |
|
458
|
|
|
if (is_null($key)) { |
|
459
|
|
|
static::$values[] = $value; |
|
460
|
|
|
} else { |
|
461
|
|
|
static::$values[$key] = $value; |
|
462
|
|
|
} |
|
463
|
|
|
} |
|
464
|
|
|
|
|
465
|
|
|
|
|
466
|
|
|
/** |
|
467
|
|
|
* Implement Array offsetExists |
|
468
|
|
|
* |
|
469
|
|
|
* @param string $key the key to set |
|
470
|
|
|
* @param mixed $value the value to set |
|
|
|
|
|
|
471
|
|
|
* @return array debug info |
|
|
|
|
|
|
472
|
|
|
* @link http://php.net/manual/en/class.arrayaccess.php |
|
473
|
|
|
*/ |
|
474
|
1 |
|
public function offsetExists($key) { |
|
475
|
1 |
|
return isset(static::$values[$key]); |
|
476
|
|
|
} |
|
477
|
|
|
|
|
478
|
|
|
|
|
479
|
|
|
/** |
|
480
|
|
|
* Implement Array offsetUnset |
|
481
|
|
|
* |
|
482
|
|
|
* @param string $key the key to set |
|
483
|
|
|
* @param mixed $value the value to set |
|
|
|
|
|
|
484
|
|
|
* @return array debug info |
|
|
|
|
|
|
485
|
|
|
* @link http://php.net/manual/en/class.arrayaccess.php |
|
486
|
|
|
*/ |
|
487
|
1 |
|
public function offsetUnset($key) { |
|
488
|
1 |
|
if (!empty(static::$overwrite)) { |
|
489
|
|
|
throw new \LogicException('Overwrite not allowed.'); |
|
490
|
|
|
} |
|
491
|
1 |
|
unset(static::$values[$key]); |
|
492
|
1 |
|
} |
|
493
|
|
|
|
|
494
|
|
|
|
|
495
|
|
|
/** |
|
496
|
|
|
* Implement Array offsetGet |
|
497
|
|
|
* |
|
498
|
|
|
* @param string $key the key to set |
|
499
|
|
|
* @param mixed $value the value to set |
|
|
|
|
|
|
500
|
|
|
* @return array debug info |
|
501
|
|
|
* @link http://php.net/manual/en/class.arrayaccess.php |
|
502
|
|
|
*/ |
|
503
|
1 |
|
public function offsetGet($key) { |
|
504
|
1 |
|
return isset(static::$values[$key]) ? static::$values[$key] : null; |
|
505
|
|
|
} |
|
506
|
|
|
} |
|
507
|
|
|
|
This check compares the return type specified in the
@returnannotation of a function or method doc comment with the types returned by the function and raises an issue if they mismatch.