<?php
/**
 * @copyright Copyright (c) 2016, ownCloud, Inc.
 *
 * @author Bernhard Posselt <dev@bernhard-posselt.com>
 * @author Bernhard Reiter <ockham@raz.or.at>
 * @author Christoph Wurst <christoph@winzerhof-wurst.at>
 * @author Morris Jobke <hey@morrisjobke.de>
 * @author Roeland Jago Douma <roeland@famdouma.nl>
 *
 * @license AGPL-3.0
 *
 * This code is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License, version 3,
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License, version 3,
 * along with this program. If not, see <http://www.gnu.org/licenses/>
 *
 */
namespace OC\Tagging;

use OCP\AppFramework\Db\DoesNotExistException;
use OCP\AppFramework\Db\Mapper;
use OCP\IDBConnection;

/**
 * Mapper for Tag entity
 */
class TagMapper extends Mapper {

	/**
	 * Constructor.
	 *
	 * @param IDBConnection $db Instance of the Db abstraction layer.
	 */
	public function __construct(IDBConnection $db) {
		parent::__construct($db, 'vcategory', Tag::class);
	}

	/**
	 * Load tags from the database.
	 *
	 * @param array|string $owners The user(s) whose tags we are going to load.
	 * @param string $type The type of item for which we are loading tags.
	 * @return array An array of Tag objects.
	 */
	public function loadTags($owners, $type) {
		if (!is_array($owners)) {
			$owners = [$owners];
		}

		$sql = 'SELECT `id`, `uid`, `type`, `category` FROM `' . $this->getTableName() . '` '
			. 'WHERE `uid` IN (' . str_repeat('?,', count($owners) - 1) . '?) AND `type` = ? ORDER BY `category`';
		return $this->findEntities($sql, array_merge($owners, [$type]));
	}

	/**
	 * Check if a given Tag object already exists in the database.
	 *
	 * @param Tag $tag The tag to look for in the database.
	 * @return bool
	 */
	public function tagExists($tag) {
		$sql = 'SELECT `id`, `uid`, `type`, `category` FROM `' . $this->getTableName() . '` '
			. 'WHERE `uid` = ? AND `type` = ? AND `category` = ?';
		try {
			$this->findEntity($sql, [$tag->getOwner(), $tag->getType(), $tag->getName()]);
		} catch (DoesNotExistException $e) {
			return false;
		}
		return true;
	}
}
