parsifal_php-ar_virt-attrs

<?php
/**
 * @package ActiveRecord
 */
namespace ActiveRecord;

/**
 * The base class for your models.
 *
 * Defining an ActiveRecord model for a table called people and orders:
 *
 * <code>
 * CREATE TABLE people(
 *   id int primary key auto_increment,
 *   parent_id int,
 *   first_name varchar(50),
 *   last_name varchar(50)
 * );
 *
 * CREATE TABLE orders(
 *   id int primary key auto_increment,
 *   person_id int not null,
 *   cost decimal(10,2),
 *   total decimal(10,2)
 * );
 * </code>
 *
 * <code>
 * class Person extends ActiveRecord\Model {
 *   static $belongs_to = array(
 *     array('parent', 'foreign_key' => 'parent_id', 'class_name' => 'Person')
 *   );
 *
 *   static $has_many = array(
 *     array('children', 'foreign_key' => 'parent_id', 'class_name' => 'Person'),
 *     array('orders')
 *   );
 *
 *   static $validates_length_of = array(
 *     array('first_name', 'within' => array(1,50)),
 *     array('last_name', 'within' => array(1,50))
 *   );
 * }
 *
 * class Order extends ActiveRecord\Model {
 *   static $belongs_to = array(
 *     array('person')
 *   );
 *
 *   static $validates_numericality_of = array(
 *     array('cost', 'greater_than' => 0),
 *     array('total', 'greater_than' => 0)
 *   );
 *
 *   static $before_save = array('calculate_total_with_tax');
 *
 *   public function calculate_total_with_tax() {
 *     $this->total = $this->cost * 0.045;
 *   }
 * }
 * </code>
 *
 * For a more in-depth look at defining models, relationships, callbacks and many other things
 * please consult our {@link http://www.phpactiverecord.org/guides Guides}.
 *
 * @package ActiveRecord
 * @see BelongsTo
 * @see CallBack
 * @see HasMany
 * @see HasAndBelongsToMany
 * @see Serialization
 * @see Validations
 */
class Model
{
    /**
     * An instance of {@link Errors} and will be instantiated once a write method is called.
     *
     * @var Errors
     */
    public $errors;

    /**
     * Contains model values as column_name => value
     *
     * @var array
     */
    private $attributes = array();

    /**
     * Flag whether or not this model's attributes have been modified since it will either be null or an array of column_names that have been modified
     *
     * @var array
     */
    private $__dirty = null;

    /**
     * Flag that determines of this model can have a writer method invoked such as: save/update/insert/delete
     *
     * @var boolean
     */
    private $__readonly = false;

    /**
     * Array of relationship objects as model_attribute_name => relationship
     *
     * @var array
     */
    private $__relationships = array();

    /**
     * Flag that determines if a call to save() should issue an insert or an update sql statement
     *
     * @var boolean
     */
    private $__new_record = true;

    /**
     * Set to the name of the connection this {@link Model} should use.
     *
     * @var string
     */
    static $connection;

    /**
     * Set to the name of the database this Model's table is in.
     *
     * @var string
     */
    static $db;

    /**
     * Set this to explicitly specify the model's table name if different from inferred name.
     *
     * If your table doesn't follow our table name convention you can set this to the
     * name of your table to explicitly tell ActiveRecord what your table is called.
     *
     * @var string
     */
    static $table_name;

    /**
     * Set this to override the default primary key name if different from default name of "id".
     *
     * @var string
     */
    static $primary_key;

    /**
     * Set this to explicitly specify the sequence name for the table.
     *
     * @var string
     */
    static $sequence;

    /**
     * Allows you to create aliases for attributes.
     *
     * <code>
     * class Person extends ActiveRecord\Model {
     *   static $alias_attribute = array(
     *     'alias_first_name' => 'first_name',
     *     'alias_last_name' => 'last_name');
     * }
     *
     * $person = Person::first();
     * $person->alias_first_name = 'Tito';
     * echo $person->alias_first_name;
     * </code>
     *
     * @var array
     */
    static $alias_attribute = array();

    /**
     * Whitelist of attributes that are checked from mass-assignment calls such as constructing a model or using update_attributes.
     *
     * This is the opposite of {@link attr_protected $attr_protected}.
     *
     * <code>
     * class Person extends ActiveRecord\Model {
     *   static $attr_accessible = array('first_name','last_name');
     * }
     *
     * $person = new Person(array(
     *   'first_name' => 'Tito',
     *   'last_name' => 'the Grief',
     *   'id' => 11111));
     *
     * echo $person->id; # => null
     * </code>
     *
     * @var array
     */
    static $attr_accessible = array();

    /**
     * Blacklist of attributes that cannot be mass-assigned.
     *
     * This is the opposite of {@link attr_accessible $attr_accessible} and the format
     * for defining these are exactly the same.
     *
     * If the attribute is both accessible and protected, it is treated as protected.
     *
     * @var array
     */
    static $attr_protected = array();

    /**
     * Delegates calls to a relationship.
     *
     * <code>
     * class Person extends ActiveRecord\Model {
     *   static $belongs_to = array(array('venue'),array('host'));
     *   static $delegate = array(
     *     array('name', 'state', 'to' => 'venue'),
     *     array('name', 'to' => 'host', 'prefix' => 'woot'));
     * }
     * </code>
     *
     * Can then do:
     *
     * <code>
     * $person->state     # same as calling $person->venue->state
     * $person->name      # same as calling $person->venue->name
     * $person->woot_name # same as calling $person->host->name
     * </code>
     *
     * @var array
     */
    static $delegate = array();

    /**
     * Constructs a model.
     *
     * When a user instantiates a new object (e.g.: it was not ActiveRecord that instantiated via a find)
     * then @var $attributes will be mapped according to the schema's defaults. Otherwise, the given
     * $attributes will be mapped via set_attributes_via_mass_assignment.
     *
     * <code>
     * new Person(array('first_name' => 'Tito', 'last_name' => 'the Grief'));
     * </code>
     *
     * @param array $attributes Hash containing names and values to mass assign to the model
     * @param boolean $guard_attributes Set to true to guard protected/non-accessible attributes
     * @param boolean $instantiating_via_find Set to true if this model is being created from a find call
     * @param boolean $new_record Set to true if this should be considered a new record
     * @return Model
     */
    public function __construct(array $attributes=array(), $guard_attributes=true, $instantiating_via_find=false, $new_record=true)
    {
        $this->__new_record = $new_record;

        // initialize attributes applying defaults
        if (!$instantiating_via_find)
        {
            foreach (static::table()->columns as $name => $meta)
                $this->attributes[$meta->inflected_name] = $meta->default;
        }

        $this->set_attributes_via_mass_assignment($attributes, $guard_attributes);

        // since all attribute assignment now goes thru assign_attributes() we want to reset
        // dirty if instantiating via find since nothing is really dirty when doing that
        if ($instantiating_via_find)
            $this->__dirty = array();

        // Let the user declare virtual attributes -- accessors that defer to
        // accessor methods.
        // (patch by Sean Gilbertson <sean.gilbertson@gmail.com>)
        if (isset(static::$virtual_attributes)) {
            foreach (static::$virtual_attributes as $attr) {
                $this->assign_attribute($attr, null);
                // $this->attributes[$attr] = null;
            }
            $this->reset_dirty();
        }

        $this->invoke_callback('after_construct',false);
    }

    /**
     * Magic method which delegates to read_attribute(). This handles firing off getter methods,
     * as they are not checked/invoked inside of read_attribute(). This circumvents the problem with
     * a getter being accessed with the same name as an actual attribute.
     *
     * You can also define customer getter methods for the model.
     *
     * EXAMPLE:
     * <code>
     * class User extends ActiveRecord\Model {
     *
     *   # define custom getter methods. Note you must
     *   # prepend get_ to your method name:
     *   function get_middle_initial() {
     *     return $this->middle_name{0};
     *   }
     * }
     *
     * $user = new User();
     * echo $user->middle_name;  # will call $user->get_middle_name()
     * </code>
     *
     * If you define a custom getter with the same name as an attribute then you
     * will need to use read_attribute() to get the attribute's value.
     * This is necessary due to the way __get() works.
     *
     * For example, assume 'name' is a field on the table and we're defining a
     * custom getter for 'name':
     *
     * <code>
     * class User extends ActiveRecord\Model {
     *
     *   # INCORRECT way to do it
     *   # function get_name() {
     *   #   return strtoupper($this->name);
     *   # }
     *
     *   function get_name() {
     *     return strtoupper($this->read_attribute('name'));
     *   }
     * }
     *
     * $user = new User();
     * $user->name = 'bob';
     * echo $user->name; # => BOB
     * </code>
     *
     *
     * @see read_attribute()
     * @param string $name Name of an attribute
     * @return mixed The value of the attribute
     */
    public function &__get($name)
    {
        // check for getter
        if (method_exists($this, "get_$name"))
        {
            $name = "get_$name";
            $value = $this->$name();
            return $value;
        }

        return $this->read_attribute($name);
    }

    /**
     * Determines if an attribute exists for this {@link Model}.
     *
     * @param string $attribute_name
     * @return boolean
     */
    public function __isset($attribute_name)
    {
        return array_key_exists($attribute_name,$this->attributes) || array_key_exists($attribute_name,static::$alias_attribute);
    }

    /**
     * Magic allows un-defined attributes to set via $attributes.
     *
     * You can also define customer setter methods for the model.
     *
     * EXAMPLE:
     * <code>
     * class User extends ActiveRecord\Model {
     *
     *   # define custom setter methods. Note you must
     *   # prepend set_ to your method name:
     *   function set_password($plaintext) {
     *     $this->encrypted_password = md5($plaintext);
     *   }
     * }
     *
     * $user = new User();
     * $user->password = 'plaintext';  # will call $user->set_password('plaintext')
     * </code>
     *
     * If you define a custom setter with the same name as an attribute then you
     * will need to use assign_attribute() to assign the value to the attribute.
     * This is necessary due to the way __set() works.
     *
     * For example, assume 'name' is a field on the table and we're defining a
     * custom setter for 'name':
     *
     * <code>
     * class User extends ActiveRecord\Model {
     *
     *   # INCORRECT way to do it
     *   # function set_name($name) {
     *   #   $this->name = strtoupper($name);
     *   # }
     *
     *   function set_name($name) {
     *     $this->assign_attribute('name',strtoupper($name));
     *   }
     * }
     *
     * $user = new User();
     * $user->name = 'bob';
     * echo $user->name; # => BOB
     * </code>
     *
     * @throws {@link UndefinedPropertyException} if $name does not exist
     * @param string $name Name of attribute, relationship or other to set
     * @param mixed $value The value
     * @return mixed The value
     */
    public function __set($name, $value)
    {
        if (array_key_exists($name, static::$alias_attribute))
            $name = static::$alias_attribute[$name];

        elseif (method_exists($this,"set_$name"))
        {
            $name = "set_$name";
            return $this->$name($value);
        }

        if (array_key_exists($name,$this->attributes))
            return $this->assign_attribute($name,$value);

        if ($name == 'id')
            return $this->assign_attribute($this->get_primary_key(true),$value);

        foreach (static::$delegate as &$item)
        {
            if (($delegated_name = $this->is_delegated($name,$item)))
                return $this->$item['to']->$delegated_name = $value;
        }

        throw new UndefinedPropertyException(get_called_class(),$name);
    }

    public function __wakeup()
    {
        // make sure the models Table instance gets initialized when waking up
        static::table();
    }

    /**
     * Assign a value to an attribute.
     *
     * @param string $name Name of the attribute
     * @param mixed &$value Value of the attribute
     * @return mixed the attribute value
     */
    public function assign_attribute($name, $value)
    {
        $table = static::table();

        if (array_key_exists($name,$table->columns) && !is_object($value))
            $value = $table->columns[$name]->cast($value,static::connection());

        // convert php's \DateTime to ours
        if ($value instanceof \DateTime)
            $value = new DateTime($value->format('Y-m-d H:i:s T'));

        // make sure DateTime values know what model they belong to so
        // dirty stuff works when calling set methods on the DateTime object
        if ($value instanceof DateTime)
            $value->attribute_of($this,$name);

        $this->attributes[$name] = $value;
        $this->flag_dirty($name);
        return $value;
    }

    /**
     * Retrieves an attribute's value or a relationship object based on the name passed. If the attribute
     * accessed is 'id' then it will return the model's primary key no matter what the actual attribute name is
     * for the primary key.
     *
     * @param string $name Name of an attribute
     * @return mixed The value of the attribute
     * @throws {@link UndefinedPropertyException} if name could not be resolved to an attribute, relationship, ...
     */
    public function &read_attribute($name)
    {
        // check for aliased attribute
        if (array_key_exists($name, static::$alias_attribute))
            $name = static::$alias_attribute[$name];

        // check for attribute
        if (array_key_exists($name,$this->attributes))
            return $this->attributes[$name];

        // check relationships if no attribute
        if (array_key_exists($name,$this->__relationships))
            return $this->__relationships[$name];

        $table = static::table();

        // this may be first access to the relationship so check Table
        if (($relationship = $table->get_relationship($name)))
        {
            $this->__relationships[$name] = $relationship->load($this);
            return $this->__relationships[$name];
        }

        if ($name == 'id')
        {
            $pk = $this->get_primary_key(true);
            if (isset($this->attributes[$pk]))
                return $this->attributes[$pk];
        }

        //do not remove - have to return null by reference in strict mode
        $null = null;

        foreach (static::$delegate as &$item)
        {
            if (($delegated_name = $this->is_delegated($name,$item)))
            {
                $to = $item['to'];
                if ($this->$to)
                {
                    $val =& $this->$to->__get($delegated_name);
                    return $val;
                }
                else
                    return $null;
            }
        }

        throw new UndefinedPropertyException(get_called_class(),$name);
    }

    /**
     * Flags an attribute as dirty.
     *
     * @param string $name Attribute name
     */
    public function flag_dirty($name)
    {
        if (!$this->__dirty)
            $this->__dirty = array();

        $this->__dirty[$name] = true;
    }

    /**
     * Returns hash of attributes that have been modified since loading the model.
     *
     * @return mixed null if no dirty attributes otherwise returns array of dirty attributes.
     */
    public function dirty_attributes()
    {
        if (!$this->__dirty)
            return null;

        $dirty = array_intersect_key($this->attributes,$this->__dirty);
        return !empty($dirty) ? $dirty : null;
    }

    /**
     * Check if a particular attribute has been modified since loading the model.
     * @param string $attribute Name of the attribute
     * @return boolean TRUE if it has been modified.
     */
    public function attribute_is_dirty($attribute)
    {
        return $this->__dirty && $this->__dirty[$attribute] && array_key_exists($attribute, $this->attributes);
    }

    /**
     * Returns a copy of the model's attributes hash.
     *
     * @return array A copy of the model's attribute data
     */
    public function attributes()
    {
        // Make sure to allow for special __get functionality.
        // (patch by Sean Gilbertson <sean.gilbertson@gmail.com>)
        $out = array();
        foreach ($this->attributes as $attr => $val) {
            $out [$attr]= $this->$attr;
        }

        return $out;
    }

    /**
     * Retrieve the primary key name.
     *
     * @param boolean Set to true to return the first value in the pk array only
     * @return string The primary key for the model
     */
    public function get_primary_key($first=false)
    {
        $pk = static::table()->pk;
        return $first ? $pk[0] : $pk;
    }

    /**
     * Returns the actual attribute name if $name is aliased.
     *
     * @param string $name An attribute name
     * @return string
     */
    public function get_real_attribute_name($name)
    {
        if (array_key_exists($name,$this->attributes))
            return $name;

        if (array_key_exists($name,static::$alias_attribute))
            return static::$alias_attribute[$name];

        return null;
    }

    /**
     * Returns array of validator data for this Model.
     *
     * Will return an array looking like:
     *
     * <code>
     * array(
     *   'name' => array(
     *     array('validator' => 'validates_presence_of'),
     *     array('validator' => 'validates_inclusion_of', 'in' => array('Bob','Joe','John')),
     *   'password' => array(
     *     array('validator' => 'validates_length_of', 'minimum' => 6))
     *   )
     * );
     * </code>
     *
     * @return array An array containing validator data for this model.
     */
    public function get_validation_rules()
    {
        require_once 'Validations.php';

        $validator = new Validations($this);
        return $validator->rules();
    }

    /**
     * Returns an associative array containing values for all the attributes in $attributes
     *
     * @param array $attributes Array containing attribute names
     * @return array A hash containing $name => $value
     */
    public function get_values_for($attributes)
    {
        $ret = array();

        foreach ($attributes as $name)
        {
            if (array_key_exists($name,$this->attributes))
                $ret[$name] = $this->attributes[$name];
        }
        return $ret;
    }

    /**
     * Retrieves the name of the table for this Model.
     *
     * @return string
     */
    public static function table_name()
    {
        return static::table()->table;
    }

    /**
     * Returns the attribute name on the delegated relationship if $name is
     * delegated or null if not delegated.
     *
     * @param string $name Name of an attribute
     * @param array $delegate An array containing delegate data
     * @return delegated attribute name or null
     */
    private function is_delegated($name, &$delegate)
    {
        if ($delegate['prefix'] != '')
            $name = substr($name,strlen($delegate['prefix'])+1);

        if (is_array($delegate) && in_array($name,$delegate['delegate']))
            return $name;

        return null;
    }

    /**
     * Determine if the model is in read-only mode.
     *
     * @return boolean
     */
    public function is_readonly()
    {
        return $this->__readonly;
    }

    /**
     * Determine if the model is a new record.
     *
     * @return boolean
     */
    public function is_new_record()
    {
        return $this->__new_record;
    }

    /**
     * Throws an exception if this model is set to readonly.
     *
     * @throws ActiveRecord\ReadOnlyException
     * @param string $method_name Name of method that was invoked on model for exception message
     */
    private function verify_not_readonly($method_name)
    {
        if ($this->is_readonly())
            throw new ReadOnlyException(get_class($this), $method_name);
    }

    /**
     * Flag model as readonly.
     *
     * @param boolean $readonly Set to true to put the model into readonly mode
     */
    public function readonly($readonly=true)
    {
        $this->__readonly = $readonly;
    }

    /**
     * Retrieve the connection for this model.
     *
     * @return Connection
     */
    public static function connection()
    {
        return static::table()->conn;
    }

    /**
     * Re-establishes the database connection with a new connection.
     *
     * @return Connection
     */
    public static function reestablish_connection()
    {
        return static::table()->reestablish_connection();
    }

    /**
     * Returns the {@link Table} object for this model.
     *
     * Be sure to call in static scoping: static::table()
     *
     * @return Table
     */
    public static function table()
    {
        return Table::load(get_called_class());
    }

    /**
     * Creates a model and saves it to the database.
     *
     * @param array $attributes Array of the models attributes
     * @param boolean $validate True if the validators should be run
     * @return Model
     */
    public static function create($attributes, $validate=true)
    {
        $class_name = get_called_class();
        $model = new $class_name($attributes);
        $model->save($validate);
        return $model;
    }

    /**
     * Save the model to the database.
     *
     * This function will automatically determine if an INSERT or UPDATE needs to occur.
     * If a validation or a callback for this model returns false, then the model will
     * not be saved and this will return false.
     *
     * If saving an existing model only data that has changed will be saved.
     *
     * @param boolean $validate Set to true or false depending on if you want the validators to run or not
     * @return boolean True if the model was saved to the database otherwise false
     */
    public function save($validate=true)
    {
        $this->verify_not_readonly('save');
        return $this->is_new_record() ? $this->insert($validate) : $this->update($validate);
    }

    /**
     * Issue an INSERT sql statement for this model's attribute.
     *
     * @see save
     * @param boolean $validate Set to true or false depending on if you want the validators to run or not
     * @return boolean True if the model was saved to the database otherwise false
     */
    private function insert($validate=true)
    {
        $this->verify_not_readonly('insert');

        if (($validate && !$this->_validate() || !$this->invoke_callback('before_create',false)))
            return false;

        $table = static::table();

        if (!($attributes = $this->dirty_attributes()))
            $attributes = $this->attributes;

        $pk = $this->get_primary_key(true);
        $use_sequence = false;

        if ($table->sequence && !isset($attributes[$pk]))
        {
            if (($conn = static::connection()) instanceof OciAdapter)
            {
                // terrible oracle makes us select the nextval first
                $attributes[$pk] = $conn->get_next_sequence_value($table->sequence);
                $table->insert($attributes);
                $this->attributes[$pk] = $attributes[$pk];
            }
            else
            {
                // unset pk that was set to null
                if (array_key_exists($pk,$attributes))
                    unset($attributes[$pk]);

                $table->insert($attributes,$pk,$table->sequence);
                $use_sequence = true;
            }
        }
        else
            $table->insert($attributes);

        // if we've got an autoincrementing/sequenced pk set it
        // don't need this check until the day comes that we decide to support composite pks
        // if (count($pk) == 1)
        {
            $column = $table->get_column_by_inflected_name($pk);

            if ($column->auto_increment || $use_sequence)
                $this->attributes[$pk] = static::connection()->insert_id($table->sequence);
        }

        $this->invoke_callback('after_create',false);
        $this->__new_record = false;
        return true;
    }

    /**
     * Issue an UPDATE sql statement for this model's dirty attributes.
     *
     * @see save
     * @param boolean $validate Set to true or false depending on if you want the validators to run or not
     * @return boolean True if the model was saved to the database otherwise false
     */
    private function update($validate=true)
    {
        $this->verify_not_readonly('update');

        if ($validate && !$this->_validate())
            return false;

        if ($this->is_dirty())
        {
            $pk = $this->values_for_pk();

            if (empty($pk))
                throw new ActiveRecordException("Cannot update, no primary key defined for: " . get_called_class());

            if (!$this->invoke_callback('before_update',false))
                return false;

            $dirty = $this->dirty_attributes();
            static::table()->update($dirty,$pk);
            $this->invoke_callback('after_update',false);
        }

        return true;
    }

    /**
     * Deletes records matching conditions in $options
     *
     * Does not instantiate models and therefore does not invoke callbacks
     *
     * Delete all using a hash:
     *
     * <code>
     * YourModel::delete_all(array('conditions' => array('name' => 'Tito')));
     * </code>
     *
     * Delete all using an array:
     *
     * <code>
     * YourModel::delete_all(array('conditions' => array('name = ?', 'Tito')));
     * </code>
     *
     * Delete all using a string:
     *
     * <code>
     * YourModel::delete_all(array('conditions' => 'name = "Tito"));
     * </code>
     *
     * An options array takes the following parameters:
     *
     * <ul>
     * <li><b>conditions:</b> Conditions using a string/hash/array</li>
     * <li><b>limit:</b> Limit number of records to delete (MySQL & Sqlite only)</li>
     * <li><b>order:</b> A SQL fragment for ordering such as: 'name asc', 'id desc, name asc' (MySQL & Sqlite only)</li>
     * </ul>
     *
     * @params array $options
     * return integer Number of rows affected
     */
    public static function delete_all($options=array())
    {
        $table = static::table();
        $conn = static::connection();
        $sql = new SQLBuilder($conn, $table->get_fully_qualified_table_name());

        $conditions = is_array($options) ? $options['conditions'] : $options;

        if (is_array($conditions) && !is_hash($conditions))
            call_user_func_array(array($sql, 'delete'), $conditions);
        else
            $sql->delete($conditions);

        if (isset($options['limit']))
            $sql->limit($options['limit']);

        if (isset($options['order']))
            $sql->order($options['order']);

        $values = $sql->bind_values();
        $ret = $conn->query(($table->last_sql = $sql->to_s()), $values);
        return $ret->rowCount();
    }

    /**
     * Updates records using set in $options
     *
     * Does not instantiate models and therefore does not invoke callbacks
     *
     * Update all using a hash:
     *
     * <code>
     * YourModel::update_all(array('set' => array('name' => "Bob")));
     * </code>
     *
     * Update all using a string:
     *
     * <code>
     * YourModel::update_all(array('set' => 'name = "Bob"'));
     * </code>
     *
     * An options array takes the following parameters:
     *
     * <ul>
     * <li><b>set:</b> String/hash of field names and their values to be updated with
     * <li><b>conditions:</b> Conditions using a string/hash/array</li>
     * <li><b>limit:</b> Limit number of records to update (MySQL & Sqlite only)</li>
     * <li><b>order:</b> A SQL fragment for ordering such as: 'name asc', 'id desc, name asc' (MySQL & Sqlite only)</li>
     * </ul>
     *
     * @params array $options
     * return integer Number of rows affected
     */
    public static function update_all($options=array())
    {
        $table = static::table();
        $conn = static::connection();
        $sql = new SQLBuilder($conn, $table->get_fully_qualified_table_name());

        $sql->update($options['set']);

        if (isset($options['conditions']) && ($conditions = $options['conditions']))
        {
            if (is_array($conditions) && !is_hash($conditions))
                call_user_func_array(array($sql, 'where'), $conditions);
            else
                $sql->where($conditions);
        }

        if (isset($options['limit']))
            $sql->limit($options['limit']);

        if (isset($options['order']))
            $sql->order($options['order']);

        $values = $sql->bind_values();
        $ret = $conn->query(($table->last_sql = $sql->to_s()), $values);
        return $ret->rowCount();

    }

    /**
     * Deletes this model from the database and returns true if successful.
     *
     * @return boolean
     */
    public function delete()
    {
        $this->verify_not_readonly('delete');

        $pk = $this->values_for_pk();

        if (empty($pk))
            throw new ActiveRecordException("Cannot delete, no primary key defined for: " . get_called_class());

        if (!$this->invoke_callback('before_destroy',false))
            return false;

        static::table()->delete($pk);
        $this->invoke_callback('after_destroy',false);

        return true;
    }

    /**
     * Helper that creates an array of values for the primary key(s).
     *
     * @return array An array in the form array(key_name => value, ...)
     */
    public function values_for_pk()
    {
        return $this->values_for(static::table()->pk);
    }

    /**
     * Helper to return a hash of values for the specified attributes.
     *
     * @param array $attribute_names Array of attribute names
     * @return array An array in the form array(name => value, ...)
     */
    public function values_for($attribute_names)
    {
        $filter = array();

        foreach ($attribute_names as $name)
            $filter[$name] = $this->$name;

        return $filter;
    }

    /**
     * Validates the model.
     *
     * @return boolean True if passed validators otherwise false
     */
    private function _validate()
    {
        require_once 'Validations.php';

        $validator = new Validations($this);
        $validation_on = 'validation_on_' . ($this->is_new_record() ? 'create' : 'update');

        foreach (array('before_validation', "before_$validation_on") as $callback)
        {
            if (!$this->invoke_callback($callback,false))
                return false;
        }

        // need to store reference b4 validating so that custom validators have access to add errors
        $this->errors = $validator->get_record();
        $validator->validate();

        foreach (array('after_validation', "after_$validation_on") as $callback)
            $this->invoke_callback($callback,false);

        if (!$this->errors->is_empty())
            return false;

        return true;
    }

    /**
     * Returns true if the model has been modified.
     *
     * @return boolean true if modified
     */
    public function is_dirty()
    {
        return empty($this->__dirty) ? false : true;
    }

    /**
     * Run validations on model and returns whether or not model passed validation.
     *
     * @see is_invalid
     * @return boolean
     */
    public function is_valid()
    {
        return $this->_validate();
    }

    /**
     * Runs validations and returns true if invalid.
     *
     * @see is_valid
     * @return boolean
     */
    public function is_invalid()
    {
        return !$this->_validate();
    }

    /**
     * Updates a model's timestamps.
     */
    public function set_timestamps()
    {
        $now = date('Y-m-d H:i:s');

        if (isset($this->updated_at))
            $this->updated_at = $now;

        if (isset($this->created_at) && $this->is_new_record())
            $this->created_at = $now;
    }

    /**
     * Mass update the model with an array of attribute data and saves to the database.
     *
     * @param array $attributes An attribute data array in the form array(name => value, ...)
     * @return boolean True if successfully updated and saved otherwise false
     */
    public function update_attributes($attributes)
    {
        $this->set_attributes($attributes);
        return $this->save();
    }

    /**
     * Updates a single attribute and saves the record without going through the normal validation procedure.
     *
     * @param string $name Name of attribute
     * @param mixed $value Value of the attribute
     * @return boolean True if successful otherwise false
     */
    public function update_attribute($name, $value)
    {
        $this->__set($name, $value);
        return $this->update(false);
    }

    /**
     * Mass update the model with data from an attributes hash.
     *
     * Unlike update_attributes() this method only updates the model's data
     * but DOES NOT save it to the database.
     *
     * @see update_attributes
     * @param array $attributes An array containing data to update in the form array(name => value, ...)
     */
    public function set_attributes(array $attributes)
    {
        $this->set_attributes_via_mass_assignment($attributes, true);
    }

    /**
     * Passing $guard_attributes as true will throw an exception if an attribute does not exist.
     *
     * @throws ActiveRecord\UndefinedPropertyException
     * @param array $attributes An array in the form array(name => value, ...)
     * @param boolean $guard_attributes Flag of whether or not protected/non-accessible attributes should be guarded
     */
    private function set_attributes_via_mass_assignment(array &$attributes, $guard_attributes)
    {
        //access uninflected columns since that is what we would have in result set
        $table = static::table();
        $exceptions = array();
        $use_attr_accessible = !empty(static::$attr_accessible);
        $use_attr_protected = !empty(static::$attr_protected);
        $connection = static::connection();

        foreach ($attributes as $name => $value)
        {
            // is a normal field on the table
            if (array_key_exists($name,$table->columns))
            {
                $value = $table->columns[$name]->cast($value,$connection);
                $name = $table->columns[$name]->inflected_name;
            }

            if ($guard_attributes)
            {
                if ($use_attr_accessible && !in_array($name,static::$attr_accessible))
                    continue;

                if ($use_attr_protected && in_array($name,static::$attr_protected))
                    continue;

                // set valid table data
                try {
                    $this->$name = $value;
                } catch (UndefinedPropertyException $e) {
                    $exceptions[] = $e->getMessage();
                }
            }
            else
            {
                // ignore OciAdapter's limit() stuff
                if ($name == 'ar_rnum__')
                    continue;

                // set arbitrary data
                $this->assign_attribute($name,$value);
            }
        }

        if (!empty($exceptions))
            throw new UndefinedPropertyException(get_called_class(),$exceptions);
    }

    /**
     * Add a model to the given named ($name) relationship.
     *
     * @internal This should <strong>only</strong> be used by eager load
     * @param Model $model
     * @param $name of relationship for this table
     * @return void
     */
    public function set_relationship_from_eager_load(Model $model=null, $name)
    {
        $table = static::table();

        if (($rel = $table->get_relationship($name)))
        {
            if ($rel->is_poly())
            {
                // if the related model is null and it is a poly then we should have an empty array
                if (is_null($model))
                    return $this->__relationships[$name] = array();
                else
                    return $this->__relationships[$name][] = $model;
            }
            else
                return $this->__relationships[$name] = $model;
        }

        throw new RelationshipException("Relationship named $name has not been declared for class: {$table->class->getName()}");
    }

    /**
     * Reloads the attributes and relationships of this object from the database.
     *
     * @return Model
     */
    public function reload()
    {
        $this->__relationships = array();
        $pk = array_values($this->get_values_for($this->get_primary_key()));

        $this->set_attributes_via_mass_assignment($this->find($pk)->attributes, false);
        $this->reset_dirty();

        return $this;
    }

    public function __clone()
    {
        $this->__relationships = array();
        $this->reset_dirty();
        return $this;
    }

    /**
     * Resets the dirty array.
     *
     * @see dirty_attributes
     */
    public function reset_dirty()
    {
        $this->__dirty = null;
    }

    /**
     * A list of valid finder options.
     *
     * @var array
     */
    static $VALID_OPTIONS = array('conditions', 'limit', 'offset', 'order', 'select', 'joins', 'include', 'readonly', 'group', 'from', 'having');

    /**
     * Enables the use of dynamic finders.
     *
     * Dynamic finders are just an easy way to do queries quickly without having to
     * specify an options array with conditions in it.
     *
     * <code>
     * SomeModel::find_by_first_name('Tito');
     * SomeModel::find_by_first_name_and_last_name('Tito','the Grief');
     * SomeModel::find_by_first_name_or_last_name('Tito','the Grief');
     * SomeModel::find_all_by_last_name('Smith');
     * SomeModel::count_by_name('Bob')
     * SomeModel::count_by_name_or_state('Bob','VA')
     * SomeModel::count_by_name_and_state('Bob','VA')
     * </code>
     *
     * You can also create the model if the find call returned no results:
     *
     * <code>
     * Person::find_or_create_by_name('Tito');
     *
     * # would be the equivalent of
     * if (!Person::find_by_name('Tito'))
     *   Person::create(array('Tito'));
     * </code>
     *
     * Some other examples of find_or_create_by:
     *
     * <code>
     * Person::find_or_create_by_name_and_id('Tito',1);
     * Person::find_or_create_by_name_and_id(array('name' => 'Tito', 'id' => 1));
     * </code>
     *
     * @param string $method Name of method
     * @param mixed $args Method args
     * @return Model
     * @throws {@link ActiveRecordException} if invalid query
     * @see find
     */
    public static function __callStatic($method, $args)
    {
        $options = static::extract_and_validate_options($args);
        $create = false;

        if (substr($method,0,17) == 'find_or_create_by')
        {
            $attributes = substr($method,17);

            // can't take any finders with OR in it when doing a find_or_create_by
            if (strpos($attributes,'_or_') !== false)
                throw new ActiveRecordException("Cannot use OR'd attributes in find_or_create_by");

            $create = true;
            $method = 'find_by' . substr($method,17);
        }

        if (substr($method,0,7) === 'find_by')
        {
            $attributes = substr($method,8);
            $options['conditions'] = SQLBuilder::create_conditions_from_underscored_string(static::connection(),$attributes,$args,static::$alias_attribute);

            if (!($ret = static::find('first',$options)) && $create)
                return static::create(SQLBuilder::create_hash_from_underscored_string($attributes,$args,static::$alias_attribute));

            return $ret;
        }
        elseif (substr($method,0,11) === 'find_all_by')
        {
            $options['conditions'] = SQLBuilder::create_conditions_from_underscored_string(static::connection(),substr($method,12),$args,static::$alias_attribute);
            return static::find('all',$options);
        }
        elseif (substr($method,0,8) === 'count_by')
        {
            $options['conditions'] = SQLBuilder::create_conditions_from_underscored_string(static::connection(),substr($method,9),$args,static::$alias_attribute);
            return static::count($options);
        }

        throw new ActiveRecordException("Call to undefined method: $method");
    }

    /**
     * Enables the use of build|create for associations.
     *
     * @param string $method Name of method
     * @param mixed $args Method args
     * @return mixed An instance of a given {@link AbstractRelationship}
     */
    public function __call($method, $args)
    {
        //check for build|create_association methods
        if (preg_match('/(build|create)_/', $method))
        {
            if (!empty($args))
                $args = $args[0];

            $association_name = str_replace(array('build_', 'create_'), '', $method);
            $method = str_replace($association_name, 'association', $method);
            $table = static::table();

            if (($association = $table->get_relationship($association_name)) ||
                  ($association = $table->get_relationship(($association_name = Utils::pluralize($association_name)))))
            {
                // access association to ensure that the relationship has been loaded
                // so that we do not double-up on records if we append a newly created
                $this->$association_name;
                return $association->$method($this, $args);
            }
        }

        throw new ActiveRecordException("Call to undefined method: $method");
    }

    /**
     * Alias for self::find('all').
     *
     * @see find
     * @return array array of records found
     */
    public static function all(/* ... */)
    {
        return call_user_func_array('static::find',array_merge(array('all'),func_get_args()));
    }

    /**
     * Get a count of qualifying records.
     *
     * <code>
     * YourModel::count(array('conditions' => 'amount > 3.14159265'));
     * </code>
     *
     * @see find
     * @return int Number of records that matched the query
     */
    public static function count(/* ... */)
    {
        $args = func_get_args();
        $options = static::extract_and_validate_options($args);
        $options['select'] = 'COUNT(*)';

        if (!empty($args))
        {
            if (is_hash($args[0]))
                $options['conditions'] = $args[0];
            else
                $options['conditions'] = call_user_func_array('static::pk_conditions',$args);
        }

        $table = static::table();
        $sql = $table->options_to_sql($options);
        $values = $sql->get_where_values();
        return static::connection()->query_and_fetch_one($sql->to_s(),$values);
    }

    /**
     * Determine if a record exists.
     *
     * <code>
     * SomeModel::exists(123);
     * SomeModel::exists(array('conditions' => array('id=? and name=?', 123, 'Tito')));
     * SomeModel::exists(array('id' => 123, 'name' => 'Tito'));
     * </code>
     *
     * @see find
     * @return boolean
     */
    public static function exists(/* ... */)
    {
        return call_user_func_array('static::count',func_get_args()) > 0 ? true : false;
    }

    /**
     * Alias for self::find('first').
     *
     * @see find
     * @return Model The first matched record or null if not found
     */
    public static function first(/* ... */)
    {
        return call_user_func_array('static::find',array_merge(array('first'),func_get_args()));
    }

    /**
     * Alias for self::find('last')
     *
     * @see find
     * @return Model The last matched record or null if not found
     */
    public static function last(/* ... */)
    {
        return call_user_func_array('static::find',array_merge(array('last'),func_get_args()));
    }

    /**
     * Find records in the database.
     *
     * Finding by the primary key:
     *
     * <code>
     * # queries for the model with id=123
     * YourModel::find(123);
     *
     * # queries for model with id in(1,2,3)
     * YourModel::find(1,2,3);
     *
     * # finding by pk accepts an options array
     * YourModel::find(123,array('order' => 'name desc'));
     * </code>
     *
     * Finding by using a conditions array:
     *
     * <code>
     * YourModel::find('first', array('conditions' => array('name=?','Tito'),
     *   'order' => 'name asc'))
     * YourModel::find('all', array('conditions' => 'amount > 3.14159265'));
     * YourModel::find('all', array('conditions' => array('id in(?)', array(1,2,3))));
     * </code>
     *
     * Finding by using a hash:
     *
     * <code>
     * YourModel::find(array('name' => 'Tito', 'id' => 1));
     * YourModel::find('first',array('name' => 'Tito', 'id' => 1));
     * YourModel::find('all',array('name' => 'Tito', 'id' => 1));
     * </code>
     *
     * An options array can take the following parameters:
     *
     * <ul>
     * <li><b>select:</b> A SQL fragment for what fields to return such as: '*', 'people.*', 'first_name, last_name, id'</li>
     * <li><b>joins:</b> A SQL join fragment such as: 'JOIN roles ON(roles.user_id=user.id)' or a named association on the model</li>
     * <li><b>include:</b> TODO not implemented yet</li>
     * <li><b>conditions:</b> A SQL fragment such as: 'id=1', array('id=1'), array('name=? and id=?','Tito',1), array('name IN(?)', array('Tito','Bob')),
     * array('name' => 'Tito', 'id' => 1)</li>
     * <li><b>limit:</b> Number of records to limit the query to</li>
     * <li><b>offset:</b> The row offset to return results from for the query</li>
     * <li><b>order:</b> A SQL fragment for order such as: 'name asc', 'name asc, id desc'</li>
     * <li><b>readonly:</b> Return all the models in readonly mode</li>
     * <li><b>group:</b> A SQL group by fragment</li>
     * </ul>
     *
     * @throws {@link RecordNotFound} if no options are passed or finding by pk and no records matched
     * @return mixed An array of records found if doing a find_all otherwise a
     *   single Model object or null if it wasn't found. NULL is only return when
     *   doing a first/last find. If doing an all find and no records matched this
     *   will return an empty array.
     */
    public static function find(/* $type, $options */)
    {
        $class = get_called_class();

        if (func_num_args() <= 0)
            throw new RecordNotFound("Couldn't find $class without an ID");

        $args = func_get_args();
        $options = static::extract_and_validate_options($args);
        $num_args = count($args);
        $single = true;

        if ($num_args > 0 && ($args[0] === 'all' || $args[0] === 'first' || $args[0] === 'last'))
        {
            switch ($args[0])
            {
                case 'all':
                    $single = false;
                    break;

                case 'last':
                    if (!array_key_exists('order',$options))
                        $options['order'] = join(' DESC, ',static::table()->pk) . ' DESC';
                    else
                        $options['order'] = SQLBuilder::reverse_order($options['order']);

                    // fall thru

                case 'first':
                    $options['limit'] = 1;
                    $options['offset'] = 0;
                    break;
            }

            $args = array_slice($args,1);
            $num_args--;
        }
        //find by pk
        elseif (1 === count($args) && 1 == $num_args)
            $args = $args[0];

        // anything left in $args is a find by pk
        if ($num_args > 0 && !isset($options['conditions']))
            return static::find_by_pk($args, $options);

        $options['mapped_names'] = static::$alias_attribute;
        $list = static::table()->find($options);

        return $single ? (!empty($list) ? $list[0] : null) : $list;
    }

    /**
     * Finder method which will find by a single or array of primary keys for this model.
     *
     * @see find
     * @param array $values An array containing values for the pk
     * @param array $options An options array
     * @return Model
     * @throws {@link RecordNotFound} if a record could not be found
     */
    public static function find_by_pk($values, $options)
    {
        $options['conditions'] = static::pk_conditions($values);
        $list = static::table()->find($options);
        $results = count($list);

        if ($results != ($expected = count($values)))
        {
            $class = get_called_class();

            if ($expected == 1)
            {
                if (!is_array($values))
                    $values = array($values);

                throw new RecordNotFound("Couldn't find $class with ID=" . join(',',$values));
            }

            $values = join(',',$values);
            throw new RecordNotFound("Couldn't find all $class with IDs ($values) (found $results, but was looking for $expected)");
        }
        return $expected == 1 ? $list[0] : $list;
    }

    /**
     * Find using a raw SELECT query.
     *
     * <code>
     * YourModel::find_by_sql("SELECT * FROM people WHERE name=?",array('Tito'));
     * YourModel::find_by_sql("SELECT * FROM people WHERE name='Tito'");
     * </code>
     *
     * @param string $sql The raw SELECT query
     * @param array $values An array of values for any parameters that needs to be bound
     * @return array An array of models
     */
    public static function find_by_sql($sql, $values=null)
    {
        return static::table()->find_by_sql($sql, $values, true);
    }

    /**
     * Helper method to run arbitrary queries against the model's database connection.
     *
     * @param string $sql SQL to execute
     * @param array $values Bind values, if any, for the query
     * @return object A PDOStatement object
     */
    public static function query($sql, $values=null)
    {
        return static::connection()->query($sql, $values);
    }

    /**
     * Determines if the specified array is a valid ActiveRecord options array.
     *
     * @param array $array An options array
     * @param bool $throw True to throw an exception if not valid
     * @return boolean True if valid otherwise valse
     * @throws {@link ActiveRecordException} if the array contained any invalid options
     */
    public static function is_options_hash($array, $throw=true)
    {
        if (is_hash($array))
        {
            $keys = array_keys($array);
            $diff = array_diff($keys,self::$VALID_OPTIONS);

            if (!empty($diff) && $throw)
                throw new ActiveRecordException("Unknown key(s): " . join(', ',$diff));

            $intersect = array_intersect($keys,self::$VALID_OPTIONS);

            if (!empty($intersect))
                return true;
        }
        return false;
    }

    /**
     * Returns a hash containing the names => values of the primary key.
     *
     * @internal This needs to eventually support composite keys.
     * @param mixed $args Primary key value(s)
     * @return array An array in the form array(name => value, ...)
     */
    public static function pk_conditions($args)
    {
        $table = static::table();
        $ret = array($table->pk[0] => $args);
        return $ret;
    }

    /**
     * Pulls out the options hash from $array if any.
     *
     * @internal DO NOT remove the reference on $array.
     * @param array &$array An array
     * @return array A valid options array
     */
    public static function extract_and_validate_options(array &$array)
    {
        $options = array();

        if ($array)
        {
            $last = &$array[count($array)-1];

            try
            {
                if (self::is_options_hash($last))
                {
                    array_pop($array);
                    $options = $last;
                }
            }
            catch (ActiveRecordException $e)
            {
                if (!is_hash($last))
                    throw $e;

                $options = array('conditions' => $last);
            }
        }
        return $options;
    }

    /**
     * Returns a JSON representation of this model.
     *
     * @see Serialization
     * @param array $options An array containing options for json serialization (see {@link Serialization} for valid options)
     * @return string JSON representation of the model
     */
    public function to_json(array $options=array())
    {
        return $this->serialize('Json', $options);
    }

    /**
     * Returns an XML representation of this model.
     *
     * @see Serialization
     * @param array $options An array containing options for xml serialization (see {@link Serialization} for valid options)
     * @return string XML representation of the model
     */
    public function to_xml(array $options=array())
    {
        return $this->serialize('Xml', $options);
    }

   /**
   * Returns an CSV representation of this model.
   * Can take optional delimiter and enclosure
   * (defaults are , and double quotes)
   *
   * Ex:
   * <code>
   * ActiveRecord\CsvSerializer::$delimiter=';';
   * ActiveRecord\CsvSerializer::$enclosure='';
   * YourModel::find('first')->to_csv(array('only'=>array('name','level')));
   * returns: Joe,2
   *
   * YourModel::find('first')->to_csv(array('only_header'=>true,'only'=>array('name','level')));
   * returns: name,level
   * </code>
   *
   * @see Serialization
   * @param array $options An array containing options for csv serialization (see {@link Serialization} for valid options)
   * @return string CSV representation of the model
   */
  public function to_csv(array $options=array())
  {
    return $this->serialize('Csv', $options);
  }

    /**
     * Returns an Array representation of this model.
     *
     * @see Serialization
     * @param array $options An array containing options for json serialization (see {@link Serialization} for valid options)
     * @return array Array representation of the model
     */
    public function to_array(array $options=array())
    {
        return $this->serialize('Array', $options);
    }

    /**
     * Creates a serializer based on pre-defined to_serializer()
     *
     * An options array can take the following parameters:
     *
     * <ul>
     * <li><b>only:</b> a string or array of attributes to be included.</li>
     * <li><b>excluded:</b> a string or array of attributes to be excluded.</li>
     * <li><b>methods:</b> a string or array of methods to invoke. The method's name will be used as a key for the final attributes array
     * along with the method's returned value</li>
     * <li><b>include:</b> a string or array of associated models to include in the final serialized product.</li>
     * </ul>
     *
     * @param string $type Either Xml, Json, Csv or Array
     * @param array $options Options array for the serializer
     * @return string Serialized representation of the model
     */
    private function serialize($type, $options)
    {
        require_once 'Serialization.php';
        $class = "ActiveRecord\\{$type}Serializer";
        $serializer = new $class($this, $options);
        return $serializer->to_s();
    }

    /**
     * Invokes the specified callback on this model.
     *
     * @param string $method_name Name of the call back to run.
     * @param boolean $must_exist Set to true to raise an exception if the callback does not exist.
     * @return boolean True if invoked or null if not
     */
    private function invoke_callback($method_name, $must_exist=true)
    {
        return static::table()->callback->invoke($this,$method_name,$must_exist);
    }

    /**
     * Executes a block of code inside a database transaction.
     *
     * <code>
     * YourModel::transaction(function()
     * {
     *   YourModel::create(array("name" => "blah"));
     * });
     * </code>
     *
     * If an exception is thrown inside the closure the transaction will
     * automatically be rolled back. You can also return false from your
     * closure to cause a rollback:
     *
     * <code>
     * YourModel::transaction(function()
     * {
     *   YourModel::create(array("name" => "blah"));
     *   throw new Exception("rollback!");
     * });
     *
     * YourModel::transaction(function()
     * {
     *   YourModel::create(array("name" => "blah"));
     *   return false; # rollback!
     * });
     * </code>
     *
     * @param Closure $closure The closure to execute. To cause a rollback have your closure return false or throw an exception.
     * @return boolean True if the transaction was committed, False if rolled back.
     */
    public static function transaction($closure)
    {
        $connection = static::connection();

        try
        {
            $connection->transaction();

            if ($closure() === false)
            {
                $connection->rollback();
                return false;
            }
            else
                $connection->commit();
        }
        catch (\Exception $e)
        {
            $connection->rollback();
            throw $e;
        }
        return true;
    }
};
?>