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

namespace yii\jui;

use yii\base\InvalidConfigException;
use yii\helpers\ArrayHelper;
use yii\helpers\Html;

/**
 * Accordion renders an accordion jQuery UI widget.
 *
 * For example:
 *
 * ```php
 * echo Accordion::widget([
 *     'items' => [
 *         [
 *             'header' => 'Section 1',
 *             'content' => 'Mauris mauris ante, blandit et, ultrices a, suscipit eget...',
 *         ],
 *         [
 *             'header' => 'Section 2',
 *             'headerOptions' => ['tag' => 'h3'],
 *             'content' => 'Sed non urna. Phasellus eu ligula. Vestibulum sit amet purus...',
 *             'options' => ['tag' => 'div'],
 *         ],
 *     ],
 *     'options' => ['tag' => 'div'],
 *     'itemOptions' => ['tag' => 'div'],
 *     'headerOptions' => ['tag' => 'h3'],
 *     'clientOptions' => ['collapsible' => false],
 * ]);
 * ```
 *
 * @see http://api.jqueryui.com/accordion/
 * @author Alexander Kochetov <creocoder@gmail.com>
 * @since 2.0
 */
class Accordion extends Widget
{
    /**
     * @var array the HTML attributes for the widget container tag. The following special options are recognized:
     *
     * - tag: string, defaults to "div", the tag name of the container tag of this widget
     *
     * @see \yii\helpers\Html::renderTagAttributes() for details on how attributes are being rendered.
     */
    public $options = [];
    /**
     * @var array list of collapsible items. Each item can be an array of the following structure:
     *
     * ~~~
     * [
     *     'header' => 'Item header',
     *     'content' => 'Item content',
     *     // the HTML attributes of the item header container tag. This will overwrite "headerOptions".
     *     'headerOptions' => [],
     *     // the HTML attributes of the item container tag. This will overwrite "itemOptions".
     *     'options' => [],
     * ]
     * ~~~
     */
    public $items = [];
    /**
     * @var array list of HTML attributes for the item container tags. This will be overwritten
     * by the "options" set in individual [[items]]. The following special options are recognized:
     *
     * - tag: string, defaults to "div", the tag name of the item container tags.
     *
     * @see \yii\helpers\Html::renderTagAttributes() for details on how attributes are being rendered.
     */
    public $itemOptions = [];
    /**
     * @var array list of HTML attributes for the item header container tags. This will be overwritten
     * by the "headerOptions" set in individual [[items]]. The following special options are recognized:
     *
     * - tag: string, defaults to "h3", the tag name of the item container tags.
     *
     * @see \yii\helpers\Html::renderTagAttributes() for details on how attributes are being rendered.
     */
    public $headerOptions = [];


    /**
     * Renders the widget.
     */
    public function run()
    {
        $options = $this->options;
        $tag = ArrayHelper::remove($options, 'tag', 'div');
        echo Html::beginTag($tag, $options) . "\n";
        echo $this->renderItems() . "\n";
        echo Html::endTag($tag) . "\n";
        $this->registerWidget('accordion');
    }

    /**
     * Renders collapsible items as specified on [[items]].
     * @return string the rendering result.
     * @throws InvalidConfigException.
     */
    protected function renderItems()
    {
        $items = [];
        foreach ($this->items as $item) {
            if (!array_key_exists('header', $item)) {
                throw new InvalidConfigException("The 'header' option is required.");
            }
            if (!array_key_exists('content', $item)) {
                throw new InvalidConfigException("The 'content' option is required.");
            }
            $headerOptions = array_merge($this->headerOptions, ArrayHelper::getValue($item, 'headerOptions', []));
            $headerTag = ArrayHelper::remove($headerOptions, 'tag', 'h3');
            $items[] = Html::tag($headerTag, $item['header'], $headerOptions);
            $options = array_merge($this->itemOptions, ArrayHelper::getValue($item, 'options', []));
            $tag = ArrayHelper::remove($options, 'tag', 'div');
            $items[] = Html::tag($tag, $item['content'], $options);
        }

        return implode("\n", $items);
    }
}
