<?php
/**
 * @author Arthur Schiwon <blizzz@owncloud.com>
 * @author Bart Visscher <bartv@thisnet.nl>
 * @author Jonny007-MKD <1-23-4-5@web.de>
 * @author Lukas Reschke <lukas@owncloud.com>
 * @author Morris Jobke <hey@morrisjobke.de>
 * @author Robin Appelman <icewind@owncloud.com>
 *
 * @copyright Copyright (c) 2015, ownCloud, Inc.
 * @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\DB;

/**
 * This handles the way we use to write queries, into something that can be
 * handled by the database abstraction layer.
 */
class Adapter {

	/**
	 * @var \OC\DB\Connection $conn
	 */
	protected $conn;

	public function __construct($conn) {
		$this->conn = $conn;
	}

	/**
	 * @param string $table name
	 * @return int id of last insert statement
	 */
	public function lastInsertId($table) {
		return $this->conn->realLastInsertId($table);
	}

	/**
	 * @param string $statement that needs to be changed so the db can handle it
	 * @return string changed statement
	 */
	public function fixupStatement($statement) {
		return $statement;
	}

	/**
	 * insert the @input values when they do not exist yet
	 * @param string $table name
	 * @param array $input key->value pair, key has to be sanitized properly
	 * @throws \OC\HintException
	 * @return int count of inserted rows
	 */
	public function insertIfNotExist($table, $input) {
		$query = 'INSERT INTO `' .$table . '` (`'
			. implode('`,`', array_keys($input)) . '`) SELECT '
			. str_repeat('?,', count($input)-1).'? ' // Is there a prettier alternative?
			. 'FROM `' . $table . '` WHERE ';

		$inserts = array_values($input);
		foreach($input as $key => $value) {
			$query .= '`' . $key . '`';
			if (is_null($value)) {
				$query .= ' IS NULL AND ';
			} else {
				$inserts[] = $value;
				$query .= ' = ? AND ';
			}
		}
		$query = substr($query, 0, strlen($query) - 5);
		$query .= ' HAVING COUNT(*) = 0';

		try {
			return $this->conn->executeUpdate($query, $inserts);
		} catch(\Doctrine\DBAL\DBALException $e) {
			$entry = 'DB Error: "'.$e->getMessage() . '"<br />';
			$entry .= 'Offending command was: ' . $query.'<br />';
			\OC_Log::write('core', $entry, \OC_Log::FATAL);
			$l = \OC::$server->getL10N('lib');
			throw new \OC\HintException(
				$l->t('Database Error'),
				$l->t('Please contact your system administrator.'),
				0,
				$e
			);
		}
	}
}