vijinho / kohana2-legacy

system/libraries/ORM.php

<?php defined('SYSPATH') or die('No direct access allowed.');
/**
 * [Object Relational Mapping][ref-orm] (ORM) is a method of abstracting database
 * access to standard PHP calls. All table rows are represented as model objects,
 * with object properties representing row data. ORM in Kohana generally follows
 * the [Active Record][ref-act] pattern.
 *
 * [ref-orm]: http://wikipedia.org/wiki/Object-relational_mapping
 * [ref-act]: http://wikipedia.org/wiki/Active_record
 *
 * $Id: ORM.php 4354 2009-05-15 16:51:37Z kiall $
 *
 * @package    ORM
 * @author     Kohana Team
 * @copyright  (c) 2007-2008 Kohana Team
 * @license    http://kohanaphp.com/license.html
 */
class ORM_Core
{

    // Current relationships
    protected $has_one                 = array();
    protected $belongs_to              = array();
    protected $has_many                = array();
    protected $has_and_belongs_to_many = array();

The variable name $has_and_belongs_to_many exceeds the maximum configured length of 20.

    // Relationships that should always be joined
    protected $load_with = array();

    // Current object
    protected $object  = array();
    protected $changed = array();
    protected $related = array();
    protected $loaded  = false;
    protected $saved   = false;
    protected $sorting;

    // Related objects
    protected $object_relations = array();
    protected $changed_relations = array();

    // Model table information
    protected $object_name;
    protected $object_plural;
    protected $table_name;
    protected $table_columns;
    protected $ignored_columns;

    // Table primary key and value
    protected $primary_key = 'id';
    protected $primary_val = 'name';

    // Array of foreign key name overloads
    protected $foreign_key = array();

    // Model configuration
    protected $table_names_plural = true;
    protected $reload_on_wakeup   = true;

    // Database configuration
    protected $db = 'default';

Avoid variables with short names like $db. Configured minimum length is 3.

    protected $db_applied = array();

    // With calls already applied
    protected $with_applied = array();

    // Stores column information for ORM models
    protected static $column_cache = array();

    /**
     * Creates and returns a new model.
     *
     * @chainable
     * @param   string  model name
     * @param   mixed   parameter for find()
     * @return  ORM
     */
    public static function factory($model, $id = null)
    {
        // Set class name
        $model = ucfirst($model).'_Model';

        return new $model($id);
    }

    /**
     * Prepares the model database connection and loads the object.
     *
     * @param   mixed  parameter for find or object to load
     * @return  void

Adding a @return annotation to constructors is generally not recommended as a constructor does not have a meaningful return value.

     */
    public function __construct($id = null)
    {
        // Set the object name and plural name
        $this->object_name   = strtolower(substr(get_class($this), 0, -6));
        $this->object_plural = inflector::plural($this->object_name);

        if (!isset($this->sorting)) {
            // Default sorting
            $this->sorting = array($this->primary_key => 'asc');
        }

        // Initialize database
        $this->__initialize();

        // Clear the object
        $this->clear();

        if (is_object($id)) {
            // Load an object
            $this->load_values((array) $id);
        } elseif (!empty($id)) {
            // Find an object
            $this->find($id);
        }
    }

    /**
     * Prepares the model database connection, determines the table name,
     * and loads column information.
     *
     * @return  void
     */
    public function __initialize()
    {
        if (! is_object($this->db)) {
            // Get database instance
            $this->db = Database::instance($this->db);
        }

        if (empty($this->table_name)) {
            // Table name is the same as the object name
            $this->table_name = $this->object_name;

            if ($this->table_names_plural === true) {
                // Make the table name plural
                $this->table_name = inflector::plural($this->table_name);
            }
        }

        if (is_array($this->ignored_columns)) {
            // Make the ignored columns mirrored = mirrored
            $this->ignored_columns = array_combine($this->ignored_columns, $this->ignored_columns);
        }

        // Load column information
        $this->reload_columns();
    }

    /**
     * Allows serialization of only the object data and state, to prevent
     * "stale" objects being unserialized, which also requires less memory.
     *
     * @return  string[]
     */
    public function __sleep()
    {
        // Store only information about the object
        return array('object_name', 'object', 'changed', 'loaded', 'saved', 'sorting');
    }

    /**
     * Prepares the database connection and reloads the object.
     *
     * @return  void
     */
    public function __wakeup()
    {
        // Initialize database
        $this->__initialize();

        if ($this->reload_on_wakeup === true) {
            // Reload the object
            $this->reload();
        }
    }

    /**
     * Handles pass-through to database methods. Calls to query methods
     * (query, get, insert, update) are not allowed. Query builder methods
     * are chainable.
     *
     * @param   string  method name
     * @param   array   method arguments
     * @return  mixed
     */
    public function __call($method, array $args)
    {
        if (method_exists($this->db, $method)) {
            if (in_array($method, array('query', 'get', 'insert', 'update', 'delete'))) {
                throw new Kohana_Exception('orm.query_methods_not_allowed');
            }

            // Method has been applied to the database
            $this->db_applied[$method] = $method;

            // Number of arguments passed
            $num_args = count($args);

            if ($method === 'select' and $num_args > 3) {
                // Call select() manually to avoid call_user_func_array
                $this->db->select($args);

The method select cannot be called on $this->db (of type string).

            } else {
                // We use switch here to manually call the database methods. This is
                // done for speed: call_user_func_array can take over 300% longer to
                // make calls. Most database methods are 4 arguments or less, so this
                // avoids almost any calls to call_user_func_array.

                switch ($num_args) {
                    case 0:
                        if (in_array($method, array('open_paren', 'close_paren', 'enable_cache', 'disable_cache'))) {
                            // Should return ORM, not Database
                            $this->db->$method();

The method $method cannot be called on $this->db (of type string).

                        } else {
                            // Support for things like reset_select, reset_write, list_tables
                            return $this->db->$method();

The method $method cannot be called on $this->db (of type string).

                        }
                    break;
                    case 1:
                        $this->db->$method($args[0]);

The method $method cannot be called on $this->db (of type string).

                    break;
                    case 2:
                        $this->db->$method($args[0], $args[1]);

The method $method cannot be called on $this->db (of type string).

                    break;
                    case 3:

This code seems to be duplicated across your project.

                        $this->db->$method($args[0], $args[1], $args[2]);

The method $method cannot be called on $this->db (of type string).

                    break;
                    case 4:

This code seems to be duplicated across your project.

                        $this->db->$method($args[0], $args[1], $args[2], $args[3]);

The method $method cannot be called on $this->db (of type string).

                    break;
                    default:
                        // Here comes the snail...
                        call_user_func_array(array($this->db, $method), $args);
                    break;
                }
            }

            return $this;
        } else {
            throw new Kohana_Exception('core.invalid_method', $method, get_class($this));
        }
    }

    /**
     * Handles retrieval of all model values, relationships, and metadata.
     *
     * @param   string  column name
     * @return  mixed
     */
    public function __get($column)
    {
        if (array_key_exists($column, $this->object)) {
            return $this->object[$column];
        } elseif (isset($this->related[$column])) {
            return $this->related[$column];
        } elseif ($column === 'primary_key_value') {
            return $this->object[$this->primary_key];
        } elseif ($model = $this->related_object($column)) {
            // This handles the has_one and belongs_to relationships

            if (in_array($model->object_name, $this->belongs_to) or ! array_key_exists($this->foreign_key($column), $model->object)) {
                // Foreign key lies in this table (this model belongs_to target model) OR an invalid has_one relationship
                $where = array($model->table_name.'.'.$model->primary_key => $this->object[$this->foreign_key($column)]);
            } else {
                // Foreign key lies in the target table (this model has_one target model)
                $where = array($this->foreign_key($column, $model->table_name) => $this->primary_key_value);

The property primary_key_value does not seem to exist. Did you mean primary_key?

            }

            // one<>alias:one relationship
            return $this->related[$column] = $model->find($where);
        } elseif (isset($this->has_many[$column])) {
            // Load the "middle" model
            $through = ORM::factory(inflector::singular($this->has_many[$column]));

            // Load the "end" model
            $model = ORM::factory(inflector::singular($column));

            // Join ON target model's primary key set to 'through' model's foreign key
            // User-defined foreign keys must be defined in the 'through' model
            $join_table = $through->table_name;
            $join_col1  = $through->foreign_key($model->object_name, $join_table);
            $join_col2  = $model->table_name.'.'.$model->primary_key;

            // one<>alias:many relationship
            return $this->related[$column] = $model
                ->join($join_table, $join_col1, $join_col2)
                ->where($through->foreign_key($this->object_name, $join_table), $this->object[$this->primary_key])
                ->find_all();
        } elseif (in_array($column, $this->has_many)) {
            // one<>many relationship
            $model = ORM::factory(inflector::singular($column));
            return $this->related[$column] = $model
                ->where($this->foreign_key($column, $model->table_name), $this->object[$this->primary_key])
                ->find_all();
        } elseif (in_array($column, $this->has_and_belongs_to_many)) {
            // Load the remote model, always singular
            $model = ORM::factory(inflector::singular($column));

            if ($this->has($model, true)) {
                // many<>many relationship
                return $this->related[$column] = $model
                    ->in($model->table_name.'.'.$model->primary_key, $this->changed_relations[$column])
                    ->find_all();
            } else {
                // empty many<>many relationship
                return $this->related[$column] = $model
                    ->where($model->table_name.'.'.$model->primary_key, null)
                    ->find_all();
            }
        } elseif (isset($this->ignored_columns[$column])) {
            return null;
        } elseif (in_array($column, array(
                'object_name', 'object_plural', // Object
                'primary_key', 'primary_val', 'table_name', 'table_columns', // Table
                'loaded', 'saved', // Status
                'has_one', 'belongs_to', 'has_many', 'has_and_belongs_to_many', 'load_with' // Relationships
            ))) {
            // Model meta information
            return $this->$column;
        } else {
            throw new Kohana_Exception('core.invalid_property', $column, get_class($this));
        }
    }

    /**
     * Handles setting of all model values, and tracks changes between values.
     *
     * @param   string  column name
     * @param   mixed   column value
     * @return  void
     */
    public function __set($column, $value)
    {
        if (isset($this->ignored_columns[$column])) {
            return null;
        } elseif (isset($this->object[$column]) or array_key_exists($column, $this->object)) {
            if (isset($this->table_columns[$column])) {
                // Data has changed
                $this->changed[$column] = $column;

                // Object is no longer saved
                $this->saved = false;
            }

            $this->object[$column] = $this->load_type($column, $value);
        } elseif (in_array($column, $this->has_and_belongs_to_many) and is_array($value)) {
            // Load relations
            $model = ORM::factory(inflector::singular($column));

            if (! isset($this->object_relations[$column])) {
                // Load relations
                $this->has($model);
            }

            // Change the relationships
            $this->changed_relations[$column] = $value;

            if (isset($this->related[$column])) {
                // Force a reload of the relationships
                unset($this->related[$column]);
            }
        } else {
            throw new Kohana_Exception('core.invalid_property', $column, get_class($this));
        }
    }

    /**
     * Checks if object data is set.
     *
     * @param   string  column name
     * @return  boolean
     */
    public function __isset($column)
    {
        return (isset($this->object[$column]) or isset($this->related[$column]));
    }

    /**
     * Unsets object data.
     *
     * @param   string  column name
     * @return  void
     */
    public function __unset($column)
    {
        unset($this->object[$column], $this->changed[$column], $this->related[$column]);
    }

    /**
     * Displays the primary key of a model when it is converted to a string.
     *
     * @return  string
     */
    public function __toString()
    {
        return (string) $this->object[$this->primary_key];
    }

    /**
     * Returns the values of this object as an array.
     *
     * @return  array
     */
    public function as_array()
    {
        $object = array();

        foreach ($this->object as $key => $val) {
            // Reconstruct the array (calls __get)
            $object[$key] = $this->$key;
        }

        return $object;
    }

    /**
     * Binds another one-to-one object to this model.  One-to-one objects
     * can be nested using 'object1:object2' syntax
     *
     * @param string $target_path
     * @return ORM_Core
     */
    public function with($target_path)
    {
        if (isset($this->with_applied[$target_path])) {
            // Don't join anything already joined
            return $this;
        }

        // Split object parts
        $objects = explode(':', $target_path);
        $target     = $this;
        foreach ($objects as $object) {
            // Go down the line of objects to find the given target
            $parent = $target;
            $target = $parent->related_object($object);

            if (! $target) {
                // Can't find related object
                return $this;
            }
        }

        $target_name = $object;

The variable $object seems to be defined by a foreach iteration on line 433. Are you sure the iterator is never empty, otherwise this variable is not defined?

        // Pop-off top object to get the parent object (user:photo:tag becomes user:photo - the parent table prefix)
        array_pop($objects);
        $parent_path = implode(':', $objects);

        if (empty($parent_path)) {
            // Use this table name itself for the parent object
            $parent_path = $this->table_name;
        } else {
            if (! isset($this->with_applied[$parent_path])) {
                // If the parent object hasn't been joined yet, do it first (otherwise LEFT JOINs fail)
                $this->with($parent_path);
            }
        }

        // Add to with_applied to prevent duplicate joins
        $this->with_applied[$target_path] = true;

        // Use the keys of the empty object to determine the columns
        $select = array_keys($target->object);
        foreach ($select as $i => $column) {
            // Add the prefix so that load_result can determine the relationship
            $select[$i] = $target_path.'.'.$column.' AS '.$target_path.':'.$column;
        }


        // Select all of the prefixed keys in the object
        $this->db->select($select);

The method select cannot be called on $this->db (of type string).

        if (in_array($target->object_name, $parent->belongs_to) or ! isset($target->object[$parent->foreign_key($target_name)])) {
            // Parent belongs_to target, use target's primary key as join column
            $join_col1 = $target->foreign_key(true, $target_path);
            $join_col2 = $parent->foreign_key($target_name, $parent_path);

The variable $parent does not seem to be defined for all execution paths leading up to this point.

        } else {
            // Parent has_one target, use parent's primary key as join column
            $join_col2 = $parent->foreign_key(true, $parent_path);
            $join_col1 = $parent->foreign_key($target_name, $target_path);
        }

        // This allows for models to use different table prefixes (sharing the same database)
        $join_table = new Database_Expression($target->db->table_prefix().$target->table_name.' AS '.$this->db->table_prefix().$target_path);

The method table_prefix cannot be called on $this->db (of type string).

        // Join the related object into the result
        $this->db->join($join_table, $join_col1, $join_col2, 'LEFT');

The method join cannot be called on $this->db (of type string).

        return $this;
    }

    /**
     * Finds and loads a single database row into the object.
     *
     * @chainable
     * @param   mixed  primary key or an array of clauses
     * @return  ORM

Should the return type not be ORM_Iterator|ORM_Core?

     */
    public function find($id = null)
    {
        if ($id !== null) {
            if (is_array($id)) {
                // Search for all clauses
                $this->db->where($id);

The method where cannot be called on $this->db (of type string).

            } else {
                // Search for a specific column
                $this->db->where($this->table_name.'.'.$this->unique_key($id), $id);

The method where cannot be called on $this->db (of type string).

            }
        }

        return $this->load_result();
    }

    /**
     * Finds multiple database rows and returns an iterator of the rows found.
     *
     * @chainable
     * @param   integer  SQL limit
     * @param   integer  SQL offset
     * @return  ORM_Iterator
     */
    public function find_all($limit = null, $offset = null)
    {
        if ($limit !== null and ! isset($this->db_applied['limit'])) {
            // Set limit
            $this->limit($limit);

The method limit does not exist on object<ORM_Core>? Since you implemented __call, maybe consider adding a @method annotation.

        }

        if ($offset !== null and ! isset($this->db_applied['offset'])) {
            // Set offset
            $this->offset($offset);

The method offset does not exist on object<ORM_Core>? Since you implemented __call, maybe consider adding a @method annotation.

        }

        return $this->load_result(true);

The expression $this->load_result(true); of type ORM_Iterator|ORM_Core adds the type ORM_Core to the return on line 535 which is incompatible with the return type documented by ORM_Core::find_all of type ORM_Iterator.

    }

    /**
     * Creates a key/value array from all of the objects available. Uses find_all
     * to find the objects.
     *
     * @param   string  key column
     * @param   string  value column
     * @return  array
     */
    public function select_list($key = null, $val = null)
    {
        if ($key === null) {
            $key = $this->primary_key;
        }

        if ($val === null) {
            $val = $this->primary_val;
        }

        // Return a select list from the results
        return $this->select($key, $val)->find_all()->select_list($key, $val);

The method select() does not exist on ORM_Core. Did you maybe mean select_list()?

    }

    /**
     * Validates the current object. This method should generally be called
     * via the model, after the $_POST Validation object has been created.
     *
     * @param   object   Validation array
     * @return  boolean
     */
    public function validate(Validation $array, $save = false)
    {
        $safe_array = $array->safe_array();

        if (! $array->submitted()) {
            foreach ($safe_array as $key => $value) {
                // Get the value from this object
                $value = $this->$key;

                if (is_object($value) and $value instanceof ORM_Iterator) {

The class ORM_Iterator does not exist. Did you forget a USE statement, or did you not list all dependencies?

                    // Convert the value to an array of primary keys
                    $value = $value->primary_key_array();
                }

                // Pre-fill data
                $array[$key] = $value;
            }
        }

        // Validate the array
        if ($status = $array->validate()) {
            // Grab only set fields (excludes missing data, unlike safe_array)
            $fields = $array->as_array();

            foreach ($fields as $key => $value) {
                if (isset($safe_array[$key])) {
                    // Set new data, ignoring any missing fields or fields without rules
                    $this->$key = $value;
                }
            }

            if ($save === true or is_string($save)) {
                // Save this object
                $this->save();

                if (is_string($save)) {
                    // Redirect to the saved page
                    url::redirect($save);
                }
            }
        }

        // Return validation status
        return $status;
    }

    /**
     * Saves the current object.
     *
     * @chainable
     * @return  ORM_Core
     */
    public function save()
    {
        if (! empty($this->changed)) {
            $data = array();
            foreach ($this->changed as $column) {
                // Compile changed data
                $data[$column] = $this->object[$column];
            }

            if ($this->loaded === true) {
                $query = $this->db

The method where cannot be called on $this->db (of type string).

$query is not used, you could remove the assignment.

                    ->where($this->primary_key, $this->object[$this->primary_key])
                    ->update($this->table_name, $data);

                // Object has been saved
                $this->saved = true;
            } else {
                $query = $this->db

The method insert cannot be called on $this->db (of type string).

                    ->insert($this->table_name, $data);

                if ($query->count() > 0) {
                    if (empty($this->object[$this->primary_key])) {
                        // Load the insert id as the primary key
                        $this->object[$this->primary_key] = $query->insert_id();
                    }

                    // Object is now loaded and saved
                    $this->loaded = $this->saved = true;
                }
            }

            if ($this->saved === true) {
                // All changes have been saved
                $this->changed = array();
            }
        }

        if ($this->saved === true and ! empty($this->changed_relations)) {
            foreach ($this->changed_relations as $column => $values) {
                // All values that were added
                $added = array_diff($values, $this->object_relations[$column]);

                // All values that were saved
                $removed = array_diff($this->object_relations[$column], $values);

                if (empty($added) and empty($removed)) {
                    // No need to bother
                    continue;
                }

                // Clear related columns
                unset($this->related[$column]);

                // Load the model
                $model = ORM::factory(inflector::singular($column));

                if (($join_table = array_search($column, $this->has_and_belongs_to_many)) === false) {
                    continue;
                }

                if (is_int($join_table)) {
                    // No "through" table, load the default JOIN table
                    $join_table = $model->join_table($this->table_name);
                }

                // Foreign keys for the join table
                $object_fk  = $this->foreign_key(null);
                $related_fk = $model->foreign_key(null);

                if (! empty($added)) {
                    foreach ($added as $id) {
                        // Insert the new relationship
                        $this->db->insert($join_table, array(

The method insert cannot be called on $this->db (of type string).

                            $object_fk  => $this->object[$this->primary_key],
                            $related_fk => $id,
                        ));
                    }
                }

                if (! empty($removed)) {
                    $this->db

The method where cannot be called on $this->db (of type string).

                        ->where($object_fk, $this->object[$this->primary_key])
                        ->in($related_fk, $removed)
                        ->delete($join_table);
                }

                // Clear all relations for this column
                unset($this->object_relations[$column], $this->changed_relations[$column]);
            }
        }

        return $this;
    }

    /**
     * Deletes the current object from the database. This does NOT destroy
     * relationships that have been created with other objects.
     *
     * @chainable
     * @return  ORM_Core
     */
    public function delete($id = null)
    {
        if ($id === null and $this->loaded) {
            // Use the the primary key value
            $id = $this->object[$this->primary_key];
        }

        // Delete this object
        $this->db->where($this->primary_key, $id)->delete($this->table_name);

The method where cannot be called on $this->db (of type string).

        return $this->clear();
    }

    /**
     * Delete all objects in the associated table. This does NOT destroy
     * relationships that have been created with other objects.
     *
     * @chainable
     * @param   array  ids to delete
     * @return  ORM_Core
     */
    public function delete_all($ids = null)
    {
        if (is_array($ids)) {
            // Delete only given ids
            $this->db->in($this->primary_key, $ids);

The method in cannot be called on $this->db (of type string).

        } elseif (is_null($ids)) {
            // Delete all records
            $this->db->where('1=1');

The method where cannot be called on $this->db (of type string).

        } else {
            // Do nothing - safeguard
            return $this;
        }

        // Delete all objects
        $this->db->delete($this->table_name);

The method delete cannot be called on $this->db (of type string).

        return $this->clear();
    }

    /**
     * Unloads the current object and clears the status.
     *
     * @chainable
     * @return  ORM_Core
     */
    public function clear()
    {
        // Create an array with all the columns set to NULL
        $columns = array_keys($this->table_columns);
        $values  = array_combine($columns, array_fill(0, count($columns), null));

        // Replace the current object with an empty one
        $this->load_values($values);

        return $this;
    }

    /**
     * Reloads the current object from the database.
     *
     * @chainable
     * @return  ORM

Should the return type not be ORM_Iterator|ORM_Core?

     */
    public function reload()
    {
        return $this->find($this->object[$this->primary_key]);
    }

    /**
     * Reload column definitions.
     *
     * @chainable
     * @param   boolean  force reloading
     * @return  ORM_Core
     */
    public function reload_columns($force = false)
    {
        if ($force === true or empty($this->table_columns)) {
            if (isset(ORM::$column_cache[$this->object_name])) {
                // Use cached column information
                $this->table_columns = ORM::$column_cache[$this->object_name];
            } else {
                // Load table columns
                ORM::$column_cache[$this->object_name] = $this->table_columns = $this->list_fields();
            }
        }

        return $this;
    }

    /**
     * Tests if this object has a relationship to a different model.
     *
     * @param   object   related ORM model
     * @param   boolean  check for any relations to given model
     * @return  boolean
     */
    public function has(ORM $model, $any = false)
    {
        // Determine plural or singular relation name
        $related = ($model->table_names_plural === true) ? $model->object_plural : $model->object_name;

        if (($join_table = array_search($related, $this->has_and_belongs_to_many)) === false) {
            return false;
        }

        if (is_int($join_table)) {
            // No "through" table, load the default JOIN table
            $join_table = $model->join_table($this->table_name);
        }

        if (! isset($this->object_relations[$related])) {
            // Load the object relationships
            $this->changed_relations[$related] = $this->object_relations[$related] = $this->load_relations($join_table, $model);
        }

        if (! $model->empty_primary_key()) {
            // Check if a specific object exists
            return in_array($model->primary_key_value, $this->changed_relations[$related]);
        } elseif ($any) {
            // Check if any relations to given model exist
            return ! empty($this->changed_relations[$related]);
        } else {
            return false;
        }
    }

    /**
     * Adds a new relationship to between this model and another.
     *
     * @param   object   related ORM model
     * @return  boolean
     */
    public function add(ORM $model)
    {
        if ($this->has($model)) {
            return true;
        }

        // Get the faked column name
        $column = $model->object_plural;

        // Add the new relation to the update
        $this->changed_relations[$column][] = $model->primary_key_value;

        if (isset($this->related[$column])) {
            // Force a reload of the relationships
            unset($this->related[$column]);
        }

        return true;
    }

    /**
     * Adds a new relationship to between this model and another.
     *
     * @param   object   related ORM model
     * @return  boolean
     */
    public function remove(ORM $model)
    {
        if (! $this->has($model)) {
            return false;
        }

        // Get the faked column name
        $column = $model->object_plural;

        if (($key = array_search($model->primary_key_value, $this->changed_relations[$column])) === false) {
            return false;
        }

        // Remove the relationship
        unset($this->changed_relations[$column][$key]);

        if (isset($this->related[$column])) {
            // Force a reload of the relationships
            unset($this->related[$column]);
        }

        return true;
    }

    /**
     * Count the number of records in the table.
     *
     * @return  integer
     */
    public function count_all()
    {
        // Return the total number of records in a table
        return $this->db->count_records($this->table_name);

The method count_records cannot be called on $this->db (of type string).

    }

    /**
     * Proxy method to Database list_fields.
     *
     * @param   string  table name or NULL to use this table
     * @return  array
     */
    public function list_fields($table = null)
    {
        if ($table === null) {
            $table = $this->table_name;
        }

        // Proxy to database
        return $this->db->list_fields($table);

The method list_fields cannot be called on $this->db (of type string).

    }

    /**
     * Proxy method to Database field_data.
     *
     * @param   string  table name
     * @return  array
     */
    public function field_data($table)
    {
        // Proxy to database
        return $this->db->field_data($table);

The method field_data cannot be called on $this->db (of type string).

    }

    /**
     * Proxy method to Database field_data.
     *
     * @chainable
     * @param   string  SQL query to clear
     * @return  ORM_Core
     */
    public function clear_cache($sql = null)
    {
        // Proxy to database
        $this->db->clear_cache($sql);

The method clear_cache cannot be called on $this->db (of type string).

        ORM::$column_cache = array();

        return $this;
    }

    /**
     * Returns the unique key for a specific value. This method is expected
     * to be overloaded in models if the model has other unique columns.
     *
     * @param   mixed   unique value
     * @return  string
     */
    public function unique_key($id)

The parameter $id is not used and could be removed.

    {
        return $this->primary_key;
    }

    /**
     * Determines the name of a foreign key for a specific table.
     *
     * @param   string  related table name
     * @param   string  prefix table name (used for JOINs)
     * @return  string
     */
    public function foreign_key($table = null, $prefix_table = null)
    {
        if ($table === true) {
            if (is_string($prefix_table)) {
                // Use prefix table name and this table's PK
                return $prefix_table.'.'.$this->primary_key;
            } else {
                // Return the name of this table's PK
                return $this->table_name.'.'.$this->primary_key;
            }
        }

        if (is_string($prefix_table)) {
            // Add a period for prefix_table.column support
            $prefix_table .= '.';
        }

        if (isset($this->foreign_key[$table])) {
            // Use the defined foreign key name, no magic here!
            $foreign_key = $this->foreign_key[$table];
        } else {
            if (! is_string($table) or ! array_key_exists($table.'_'.$this->primary_key, $this->object)) {
                // Use this table
                $table = $this->table_name;

                if (strpos($table, '.') !== false) {
                    // Hack around support for PostgreSQL schemas
                    list($schema, $table) = explode('.', $table, 2);

The assignment to $schema is unused. Consider omitting it like so list($first,,$third).

                }

                if ($this->table_names_plural === true) {
                    // Make the key name singular
                    $table = inflector::singular($table);
                }
            }

            $foreign_key = $table.'_'.$this->primary_key;
        }

        return $prefix_table.$foreign_key;
    }

    /**
     * This uses alphabetical comparison to choose the name of the table.
     *
     * Example: The joining table of users and roles would be roles_users,
     * because "r" comes before "u". Joining products and categories would
     * result in categories_products, because "c" comes before "p".
     *
     * Example: zoo > zebra > robber > ocean > angel > aardvark
     *
     * @param   string  table name
     * @return  string
     */
    public function join_table($table)
    {
        if ($this->table_name > $table) {
            $table = $table.'_'.$this->table_name;
        } else {
            $table = $this->table_name.'_'.$table;
        }

        return $table;
    }

    /**
     * Returns an ORM model for the given object name;
     *
     * @param   string  object name
     * @return  ORM
     */
    protected function related_object($object)
    {
        if (isset($this->has_one[$object])) {
            $object = ORM::factory($this->has_one[$object]);
        } elseif (isset($this->belongs_to[$object])) {
            $object = ORM::factory($this->belongs_to[$object]);
        } elseif (in_array($object, $this->has_one) or in_array($object, $this->belongs_to)) {
            $object = ORM::factory($object);
        } else {
            return false;

The return type of return false; (false) is incompatible with the return type documented by ORM_Core::related_object of type ORM.

        }

        return $object;
    }

    /**
     * Loads an array of values into into the current object.
     *
     * @chainable
     * @param   array  values to load
     * @return  ORM_Core
     */
    public function load_values(array $values)
    {
        if (array_key_exists($this->primary_key, $values)) {
            // Replace the object and reset the object status
            $this->object = $this->changed = $this->related = array();

            // Set the loaded and saved object status based on the primary key
            $this->loaded = $this->saved = ($values[$this->primary_key] !== null);
        }

        // Related objects
        $related = array();

        foreach ($values as $column => $value) {
            if (strpos($column, ':') === false) {
                if (isset($this->table_columns[$column])) {
                    // The type of the value can be determined, convert the value
                    $value = $this->load_type($column, $value);
                }

                $this->object[$column] = $value;
            } else {
                list($prefix, $column) = explode(':', $column, 2);

                $related[$prefix][$column] = $value;
            }
        }

        if (! empty($related)) {
            foreach ($related as $object => $values) {
                // Load the related objects with the values in the result
                $this->related[$object] = $this->related_object($object)->load_values($values);
            }
        }

        return $this;
    }

    /**
     * Loads a value according to the types defined by the column metadata.
     *
     * @param   string  column name
     * @param   mixed   value to load
     * @return  mixed
     */
    protected function load_type($column, $value)
    {
        $type = gettype($value);
        if ($type == 'object' or $type == 'array' or ! isset($this->table_columns[$column])) {
            return $value;
        }

        // Load column data
        $column = $this->table_columns[$column];

        if ($value === null and ! empty($column['null'])) {
            return $value;
        }

        if (! empty($column['binary']) and ! empty($column['exact']) and (int) $column['length'] === 1) {
            // Use boolean for BINARY(1) fields
            $column['type'] = 'boolean';
        }

        switch ($column['type']) {
            case 'int':
                if ($value === '' and ! empty($column['null'])) {
                    // Forms will only submit strings, so empty integer values must be null
                    $value = null;
                } elseif ((float) $value > PHP_INT_MAX) {
                    // This number cannot be represented by a PHP integer, so we convert it to a string
                    $value = (string) $value;
                } else {
                    $value = (int) $value;
                }
            break;
            case 'float':
                $value = (float) $value;
            break;
            case 'boolean':
                $value = (bool) $value;
            break;
            case 'string':
                $value = (string) $value;
            break;
        }

        return $value;
    }

    /**
     * Loads a database result, either as a new object for this model, or as
     * an iterator for multiple rows.
     *
     * @chainable
     * @param   boolean       return an iterator or load a single row
     * @return  ORM           for single rows
     * @return  ORM_Iterator  for multiple rows

Should the return type not be ORM_Iterator|ORM_Core?

     */
    protected function load_result($array = false)
    {
        if ($array === false) {
            // Only fetch 1 record
            $this->db->limit(1);

The method limit cannot be called on $this->db (of type string).

        }

        if (! isset($this->db_applied['select'])) {
            // Select all columns by default
            $this->db->select($this->table_name.'.*');

The method select cannot be called on $this->db (of type string).

        }

        if (! empty($this->load_with)) {
            foreach ($this->load_with as $alias => $object) {
                // Join each object into the results
                if (is_string($alias)) {
                    // Use alias
                    $this->with($alias);
                } else {
                    // Use object
                    $this->with($object);
                }
            }
        }

        if (! isset($this->db_applied['orderby']) and ! empty($this->sorting)) {
            $sorting = array();
            foreach ($this->sorting as $column => $direction) {
                if (strpos($column, '.') === false) {
                    // Keeps sorting working properly when using JOINs on
                    // tables with columns of the same name
                    $column = $this->table_name.'.'.$column;
                }

                $sorting[$column] = $direction;
            }

            // Apply the user-defined sorting
            $this->db->orderby($sorting);

The method orderby cannot be called on $this->db (of type string).

        }

        // Load the result
        $result = $this->db->get($this->table_name);

The method get cannot be called on $this->db (of type string).

        if ($array === true) {
            // Return an iterated result
            return new ORM_Iterator($this, $result);
        }

        if ($result->count() === 1) {
            // Load object values
            $this->load_values($result->result(false)->current());
        } else {
            // Clear the object, nothing was found
            $this->clear();
        }

        return $this;
    }

    /**
     * Return an array of all the primary keys of the related table.
     *
     * @param   string  table name
     * @param   object  ORM model to find relations of
     * @return  array
     */
    protected function load_relations($table, ORM $model)
    {
        // Save the current query chain (otherwise the next call will clash)
        $this->db->push();

The method push cannot be called on $this->db (of type string).

        $query = $this->db

The method select cannot be called on $this->db (of type string).

            ->select($model->foreign_key(null).' AS id')
            ->from($table)
            ->where($this->foreign_key(null, $table), $this->object[$this->primary_key])
            ->get()
            ->result(true);

        $this->db->pop();

The method pop cannot be called on $this->db (of type string).

        $relations = array();
        foreach ($query as $row) {
            $relations[] = $row->id;
        }

        return $relations;
    }

    /**
     * Returns whether or not primary key is empty
     *
     * @return bool
     */
    protected function empty_primary_key()
    {
        return (empty($this->object[$this->primary_key]) and $this->object[$this->primary_key] !== '0');
    }
} // End ORM