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

namespace yii\widgets;

use Yii;
use yii\base\Widget;
use yii\base\Model;
use yii\base\InvalidConfigException;
use yii\helpers\Html;

/**
 * InputWidget is the base class for widgets that collect user inputs.
 *
 * An input widget can be associated with a data model and an attribute,
 * or a name and a value. If the former, the name and the value will
 * be generated automatically.
 *
 * Classes extending from this widget can be used in an [[\yii\widgets\ActiveForm|ActiveForm]]
 * using the [[\yii\widgets\ActiveField::widget()|widget()]] method, for example like this:
 *
 * ```php
 * <?= $form->field($model, 'from_date')->widget('WidgetClassName', [
 *     // configure additional widget properties here
 * ]) ?>
 * ```
 *
 * For more details and usage information on InputWidget, see the [guide article on forms](guide:input-forms).
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @since 2.0
 */
class InputWidget extends Widget
{
    /**
     * @var \yii\widgets\ActiveField active input field, which triggers this widget rendering.
     * This field will be automatically filled up in case widget instance is created via [[\yii\widgets\ActiveField::widget()]].
     * @since 2.0.11
     */
    public $field;
    /**
     * @var Model the data model that this widget is associated with.
     */
    public $model;
    /**
     * @var string the model attribute that this widget is associated with.
     */
    public $attribute;
    /**
     * @var string the input name. This must be set if [[model]] and [[attribute]] are not set.
     */
    public $name;
    /**
     * @var string the input value.
     */
    public $value;
    /**
     * @var array the HTML attributes for the input tag.
     * @see \yii\helpers\Html::renderTagAttributes() for details on how attributes are being rendered.
     */
    public $options = [];


    /**
     * Initializes the widget.
     * If you override this method, make sure you call the parent implementation first.
     */
    public function init()
    {
        if ($this->name === null && !$this->hasModel()) {
            throw new InvalidConfigException("Either 'name', or 'model' and 'attribute' properties must be specified.");
        }
        if (!isset($this->options['id'])) {
            $this->options['id'] = $this->hasModel() ? Html::getInputId($this->model, $this->attribute) : $this->getId();
        }
        parent::init();
    }

    /**
     * @return bool whether this widget is associated with a data model.
     */
    protected function hasModel()
    {
        return $this->model instanceof Model && $this->attribute !== null;
    }
}
