<?php
/**
 * @package     Joomla.Plugin
 * @subpackage  Fields.Media
 *
 * @copyright   (C) 2017 Open Source Matters, Inc. <https://www.joomla.org>
 * @license     GNU General Public License version 2 or later; see LICENSE.txt
 */

defined('_JEXEC') or die;

use Joomla\CMS\Factory;
use Joomla\CMS\Form\Form;

/**
 * Fields Media Plugin
 *
 * @since  3.7.0
 */
class PlgFieldsMedia extends \Joomla\Component\Fields\Administrator\Plugin\FieldsPlugin
{
	/**
	 * Transforms the field into a DOM XML element and appends it as a child on the given parent.
	 *
	 * @param   stdClass    $field   The field.
	 * @param   DOMElement  $parent  The field node parent.
	 * @param   Form        $form    The form.
	 *
	 * @return  DOMElement
	 *
	 * @since   4.0.0
	 */
	public function onCustomFieldsPrepareDom($field, DOMElement $parent, Form $form)
	{
		$fieldNode = parent::onCustomFieldsPrepareDom($field, $parent, $form);

		if (!$fieldNode)
		{
			return $fieldNode;
		}

		$fieldNode->setAttribute('type', 'accessiblemedia');

		if (Factory::getApplication()->getIdentity()->authorise('core.create', 'com_media'))
		{
			$fieldNode->setAttribute('disabled', 'false');
		}

		return $fieldNode;
	}

	/**
	 * Before prepares the field value.
	 *
	 * @param   string     $context  The context.
	 * @param   \stdclass  $item     The item.
	 * @param   \stdclass  $field    The field.
	 *
	 * @return  void
	 *
	 * @since   4.0.0
	 */
	public function onCustomFieldsBeforePrepareField($context, $item, $field)
	{
		// Check if the field should be processed by us
		if (!$this->isTypeSupported($field->type))
		{
			return;
		}

		// Check if the field value is an old (string) value
		$field->value = $this->checkValue($field->value);
	}

	/**
	 * Before prepares the field value.
	 *
	 * @param   string  $value  The value to check.
	 *
	 * @return  array  The checked value
	 *
	 * @since   4.0.0
	 */
	private function checkValue($value)
	{
		json_decode($value);

		if (json_last_error() === JSON_ERROR_NONE)
		{
			return (array) json_decode($value, true);
		}

		return array('imagefile' => $value, 'alt_text' => '');
	}
}