SimplePie_Cache_DB

{
	/**
	 * Helper for database conversion
	 *
	 * Converts a given {@see SimplePie} object into data to be stored
	 *
	 * @param SimplePie $data
	 * @return array First item is the serialized data for storage, second item is the unique ID for this item
	 */
	protected static function prepare_simplepie_object_for_cache($data)
	{
		$items = $data->get_items();
		$items_by_id = array();

		if (!empty($items))
		{
			foreach ($items as $item)
			{
				$items_by_id[$item->get_id()] = $item;
			}

			if (count($items_by_id) !== count($items))
			{
				$items_by_id = array();
				foreach ($items as $item)
				{
					$items_by_id[$item->get_id(true)] = $item;
				}
			}

			if (isset($data->data['child'][SIMPLEPIE_NAMESPACE_ATOM_10]['feed'][0]))
			{
				$channel =& $data->data['child'][SIMPLEPIE_NAMESPACE_ATOM_10]['feed'][0];
			}
			elseif (isset($data->data['child'][SIMPLEPIE_NAMESPACE_ATOM_03]['feed'][0]))
			{
				$channel =& $data->data['child'][SIMPLEPIE_NAMESPACE_ATOM_03]['feed'][0];
			}
			elseif (isset($data->data['child'][SIMPLEPIE_NAMESPACE_RDF]['RDF'][0]))
			{
				$channel =& $data->data['child'][SIMPLEPIE_NAMESPACE_RDF]['RDF'][0];
			}
			elseif (isset($data->data['child'][SIMPLEPIE_NAMESPACE_RSS_20]['rss'][0]['child'][SIMPLEPIE_NAMESPACE_RSS_20]['channel'][0]))
			{
				$channel =& $data->data['child'][SIMPLEPIE_NAMESPACE_RSS_20]['rss'][0]['child'][SIMPLEPIE_NAMESPACE_RSS_20]['channel'][0];
			}
			else
			{
				$channel = null;
			}

			if ($channel !== null)
			{
				if (isset($channel['child'][SIMPLEPIE_NAMESPACE_ATOM_10]['entry']))
				{
					unset($channel['child'][SIMPLEPIE_NAMESPACE_ATOM_10]['entry']);
				}
				if (isset($channel['child'][SIMPLEPIE_NAMESPACE_ATOM_03]['entry']))
				{
					unset($channel['child'][SIMPLEPIE_NAMESPACE_ATOM_03]['entry']);
				}
				if (isset($channel['child'][SIMPLEPIE_NAMESPACE_RSS_10]['item']))
				{
					unset($channel['child'][SIMPLEPIE_NAMESPACE_RSS_10]['item']);
				}
				if (isset($channel['child'][SIMPLEPIE_NAMESPACE_RSS_090]['item']))
				{
					unset($channel['child'][SIMPLEPIE_NAMESPACE_RSS_090]['item']);
				}
				if (isset($channel['child'][SIMPLEPIE_NAMESPACE_RSS_20]['item']))
				{
					unset($channel['child'][SIMPLEPIE_NAMESPACE_RSS_20]['item']);
				}
			}
			if (isset($data->data['items']))
			{
				unset($data->data['items']);
			}
			if (isset($data->data['ordered_items']))
			{
				unset($data->data['ordered_items']);
			}
		}
		return array(serialize($data->data), $items_by_id);
	}
}