<?php
/**
 * @link http://www.yiiframework.com/
 * @copyright Copyright (c) 2008 Yii Software LLC
 * @license http://www.yiiframework.com/license/
 */

namespace yii\base;

use yii\validators\Validator;

/**
 * DynamicModel is a model class primarily used to support ad-hoc data validation.
 *
 * The typical usage of DynamicModel is as follows,
 *
 * ```php
 * public function actionSearch($name, $email)
 * {
 *     $model = DynamicModel::validateData(compact('name', 'email'), [
 *         [['name', 'email'], 'string', 'max' => 128]],
 *         ['email', 'email'],
 *     ]);
 *     if ($model->hasErrors()) {
 *         // validation fails
 *     } else {
 *         // validation succeeds
 *     }
 * }
 * ```
 *
 * The above example shows how to validate `$name` and `$email` with the help of DynamicModel.
 * The [[validateData()]] method creates an instance of DynamicModel, defines the attributes
 * using the given data (`name` and `email` in this example), and then calls [[Model::validate()]].
 *
 * You can check the validation result by [[hasErrors()]], like you do with a normal model.
 * You may also access the dynamic attributes defined through the model instance, e.g.,
 * `$model->name` and `$model->email`.
 *
 * Alternatively, you may use the following more "classic" syntax to perform ad-hoc data validation:
 *
 * ```php
 * $model = new DynamicModel(compact('name', 'email'));
 * $model->addRule(['name', 'email'], 'string', ['max' => 128])
 *     ->addRule('email', 'email')
 *     ->validate();
 * ```
 *
 * DynamicModel implements the above ad-hoc data validation feature by supporting the so-called
 * "dynamic attributes". It basically allows an attribute to be defined dynamically through its constructor
 * or [[defineAttribute()]].
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @since 2.0
 */
class DynamicModel extends Model
{
    private $_attributes = [];

    /**
     * Constructors.
     * @param array $attributes the dynamic attributes (name-value pairs, or names) being defined
     * @param array $config     the configuration array to be applied to this object.
     */
    public function __construct(array $attributes = [], $config = [])
    {
        foreach ($attributes as $name => $value) {
            if (is_integer($name)) {
                $this->_attributes[$value] = null;
            } else {
                $this->_attributes[$name] = $value;
            }
        }
    }

    /**
     * @inheritdoc
     */
    public function __get($name)
    {
        if (array_key_exists($name, $this->_attributes)) {
            return $this->_attributes[$name];
        } else {
            return parent::__get($name);
        }
    }

    /**
     * @inheritdoc
     */
    public function __set($name, $value)
    {
        if (array_key_exists($name, $this->_attributes)) {
            $this->_attributes[$name] = $value;
        } else {
            parent::__set($name, $value);
        }
    }

    /**
     * @inheritdoc
     */
    public function __isset($name)
    {
        if (array_key_exists($name, $this->_attributes)) {
            return isset($this->_attributes[$name]);
        } else {
            return parent::__isset($name);
        }
    }

    /**
     * @inheritdoc
     */
    public function __unset($name)
    {
        if (array_key_exists($name, $this->_attributes)) {
            unset($this->_attributes[$name]);
        } else {
            parent::__unset($name);
        }
    }

    /**
     * Defines an attribute.
     * @param string $name  the attribute name
     * @param mixed  $value the attribute value
     */
    public function defineAttribute($name, $value = null)
    {
        $this->_attributes[$name] = $value;
    }

    /**
     * Undefines an attribute.
     * @param string $name the attribute name
     */
    public function undefineAttribute($name)
    {
        unset($this->_attributes[$name]);
    }

    /**
     * Adds a validation rule to this model.
     * You can also directly manipulate [[validators]] to add or remove validation rules.
     * This method provides a shortcut.
     * @param  string|array $attributes the attribute(s) to be validated by the rule
     * @param  mixed        $validator  the validator for the rule.This can be a built-in validator name,
     *                                  a method name of the model class, an anonymous function, or a validator class name.
     * @param  array        $options    the options (name-value pairs) to be applied to the validator
     * @return static       the model itself
     */
    public function addRule($attributes, $validator, $options = [])
    {
        $validators = $this->getValidators();
        $validators->append(Validator::createValidator($validator, $this, (array) $attributes, $options));

        return $this;
    }

    /**
     * Validates the given data with the specified validation rules.
     * This method will create a DynamicModel instance, populate it with the data to be validated,
     * create the specified validation rules, and then validate the data using these rules.
     * @param  array                  $data  the data (name-value pairs) to be validated
     * @param  array                  $rules the validation rules. Please refer to [[Model::rules()]] on the format of this parameter.
     * @return static                 the model instance that contains the data being validated
     * @throws InvalidConfigException if a validation rule is not specified correctly.
     */
    public static function validateData(array $data, $rules = [])
    {
        /** @var DynamicModel $model */
        $model = new static($data);
        if (!empty($rules)) {
            $validators = $model->getValidators();
            foreach ($rules as $rule) {
                if ($rule instanceof Validator) {
                    $validators->append($rule);
                } elseif (is_array($rule) && isset($rule[0], $rule[1])) { // attributes, validator type
                    $validator = Validator::createValidator($rule[1], $model, (array) $rule[0], array_slice($rule, 2));
                    $validators->append($validator);
                } else {
                    throw new InvalidConfigException('Invalid validation rule: a rule must specify both attribute names and validator type.');
                }
            }
            $model->validate();
        }

        return $model;
    }

    /**
     * @inheritdoc
     */
    public function attributes()
    {
        return array_keys($this->_attributes);
    }
}
