<?php
  
  /**
   * Copyright (c) 2012 Robin Appelman <icewind@owncloud.com>
   * This file is licensed under the Affero General Public License version 3 or
   * later.
   * See the COPYING-README file.
   */
  
  namespace OCA\Media;
  
  //implementation of ampache's xml api
  class Ampache {
  	/**
  	 * @var Collection $collection
  	 */
  	private $collection;
  
  	public function error($code, $msg) {
  		$tmpl = new \OC_Template('media', 'ampache/error');
  		$tmpl->assign('code', $code);
  		$tmpl->assign('msg', $msg);
  		$tmpl->printPage();
  		die();
  	}
  
  	/**
  	 * do the initial handshake
  	 *
  	 * @param array $params
  	 */
  	public function handshake($params) {
  		$auth = (isset($params['auth'])) ? $params['auth'] : false;
  		$user = (isset($params['user'])) ? $params['user'] : false;
  		$time = (isset($params['timestamp'])) ? $params['timestamp'] : false;
  		$now = time();
  		if ($now - $time > (10 * 60)) {
  			$this->error(400, 'timestamp is more then 10 minutes old');
  		}
  		if ($auth and $user and $time) {
  			$query = \OCP\DB::prepare("SELECT `user_id`, `user_password_sha256` FROM `*PREFIX*media_users` WHERE `user_id`=?");
  			$result = $query->execute(array($user));
  			if ($row = $result->fetchRow()) {
  				$pass = $row['user_password_sha256'];
  				$key = hash('sha256', $time . $pass);
  				if ($key == $auth) {
  					$token = hash('sha256', 'oc_media_' . $key);
  					$this->collection = new Collection($row['user_id']);
  					$date = date('c'); //todo proper update/add/clean dates
  					$songs = $this->collection->getSongCount();
  					$artists = $this->collection->getArtistCount();
  					$albums = $this->collection->getAlbumCount();
  					$query = \OCP\DB::prepare("INSERT INTO `*PREFIX*media_sessions` (`token`, `user_id`, `start`) VALUES (?, ?, now());");
  					$query->execute(array($token, $user));
  					$expire = date('c', time() + 600);
  
  					$tmpl = new \OC_Template('media', 'ampache/handshake');
  					$tmpl->assign('token', $token);
  					$tmpl->assign('date', $date);
  					$tmpl->assign('songs', $songs);
  					$tmpl->assign('artists', $artists);
  					$tmpl->assign('albums', $albums);
  					$tmpl->assign('expire', $expire);
  					$tmpl->printPage();
  					return;
  				}
  			}
  			$this->error(400, 'Invalid login');
  		} else {
  			$this->error(400, 'Missing arguments');
  		}
  	}
  
  	public function ping($params) {
  		if (isset($params['auth'])) {
  			if ($this->checkAuth($params['auth'])) {
  				$this->updateAuth($params['auth']);
  			} else {
  				$this->error(401, 'Invalid login');
  				return;
  			}
  		}
  		$tmpl = new \OC_Template('media', 'ampache/ping');
  		$tmpl->printPage();
  	}
  
  	public function checkAuth($auth) {
  		if (is_array($auth)) {
  			if (isset($auth['auth'])) {
  				$auth = $auth['auth'];
  			} else {
  				return false;
  			}
  		}
  		$CONFIG_DBTYPE = \OCP\Config::getSystemValue("dbtype", "sqlite");
  		if ($CONFIG_DBTYPE == 'pgsql') {
  			$interval = ' \'600s\'::interval ';
  		} else {
  			$interval = '600';
  		}
  		//remove old sessions
  		$query = \OCP\DB::prepare("DELETE FROM `*PREFIX*media_sessions` WHERE `start`<(NOW() - " . $interval . ")");
  		$query->execute();
  
  		$query = \OCP\DB::prepare("SELECT `user_id` FROM `*PREFIX*media_sessions` WHERE `token`=?");
  		$result = $query->execute(array($auth));
  		if ($row = $result->fetchRow()) {
  			$this->collection = new Collection($row['user_id']);
  			return true;
  		} else {
  			return false;
  		}
  	}
  
  	public function updateAuth($auth) {
  		$query = \OCP\DB::prepare("UPDATE `*PREFIX*media_sessions` SET `start`=CURRENT_TIMESTAMP WHERE `token`=?");
  		$query->execute(array($auth));
  	}
  
  	private function printArtists($artists) {
  		header('Content-Type:  text/xml');
  		$tmpl = new \OC_Template('media', 'ampache/artists');
  
  		foreach ($artists as $artist) {
  			$artistData = array();
  			$artistData['albums'] = count($this->collection->getAlbums($artist['artist_id']));
  			$artistData['songs'] = count($this->collection->getSongs($artist['artist_id']));
  			$artistData['id'] = $artist['artist_id'];
  			$artistData['name'] = xmlentities($artist['artist_name']);
  			$tmpl->append('artists', $artistData);
  		}
  		$tmpl->printPage();
  	}
  
  	private function printAlbums($albums, $artistName = false) {
  		header('Content-Type:  text/xml');
  		$tmpl = new \OC_Template('media', 'ampache/albums');
  		foreach ($albums as $album) {
  			$albumData = array();
  			if ($artistName) {
  				$albumData['artist_name'] = xmlentities($artistName);
  			} else {
  				$albumData['artist_name'] = xmlentities($this->collection->getArtistName($album['album_artist']));
  			}
  			$albumData['songs'] = count($this->collection->getSongs($album['album_artist'], $album['album_id']));
  			$albumData['id'] = $album['album_id'];
  			$albumData['name'] = xmlentities($album['album_name']);
  			$albumData['artist'] = $album['album_artist'];
  			$tmpl->append('albums', $albumData);
  		}
  		$tmpl->printPage();
  	}
  
  	private function printSongs($songs, $artistName = false, $albumName = false) {
  		header('Content-Type:  text/xml');
  		$tmpl = new \OC_Template('media', 'ampache/songs');
  
  		foreach ($songs as $song) {
  			$songData = array();
  			if ($artistName) {
  				$songData['artist_name'] = xmlentities($artistName);
  			} else {
  				$songData['artist_name'] = xmlentities($this->collection->getArtistName($song['song_artist']));
  			}
  			if ($albumName) {
  				$songData['album_name'] = xmlentities($albumName);
  			} else {
  				$songData['album_name'] = xmlentities($this->collection->getAlbumName($song['song_album']));
  			}
  			$songData['id'] = $song['song_id'];
  			$songData['name'] = xmlentities($song['song_name']);
  			$songData['artist'] = $song['song_artist'];
  			$songData['album'] = $song['song_album'];
  			$songData['length'] = $song['song_length'];
  			$songData['track'] = $song['song_track'];
  			$songData['size'] = $song['song_size'];
  			$url = \OCP\Util::linkToRemote('ampache') . 'server/xml.server.php/?action=play&song=' . $songData['id'] . '&auth=' . $_GET['auth'];
  			$songData['url'] = xmlentities($url);
  			$tmpl->append('songs', $songData);
  		}
  		$tmpl->printPage();
  	}
  
  	public function artists($params) {
  		if (!$this->checkAuth($params)) {
  			$this->error(401, 'Invalid Login');
  		}
  		$filter = isset($params['filter']) ? $params['filter'] : '';
  		$exact = isset($params['exact']) ? ($params['exact'] == 'true') : false;
  		$artists = $this->collection->getArtists($filter, $exact);
  		$this->printArtists($artists);
  	}
  
  	public function artist_songs($params) {
  		if (!$this->checkAuth($params)) {
  			$this->error(401, 'Invalid Login');
  		}
  		$filter = isset($params['filter']) ? $params['filter'] : '';
  		$songs = $this->collection->getSongs($filter);
  		$artist = $this->collection->getArtistName($filter);
  		$this->printSongs($songs, $artist);
  	}
  
  	public function artist_albums($params) {
  		if (!$this->checkAuth($params)) {
  			$this->error(401, 'Invalid Login');
  		}
  		$filter = isset($params['filter']) ? $params['filter'] : '';
  		$albums = $this->collection->getAlbums($filter);
  		$artist = $this->collection->getArtistName($filter);
  		$this->printAlbums($albums, $artist);
  	}
  
  	public function albums($params) {
  		if (!$this->checkAuth($params)) {
  			$this->error(401, 'Invalid Login');
  		}
  		$filter = isset($params['filter']) ? $params['filter'] : '';
  		$exact = isset($params['exact']) ? ($params['exact'] == 'true') : false;
  		$albums = $this->collection->getAlbums(0, $filter, $exact);
  		$this->printAlbums($albums, false);
  	}
  
  	public function album_songs($params) {
  		if (!$this->checkAuth($params)) {
  			$this->error(401, 'Invalid Login');
  		}
  		$songs = $this->collection->getSongs(0, $params['filter']);
  		if (count($songs) > 0) {
  			$artist = $this->collection->getArtistName($songs[0]['song_artist']);
  		} else {
  			$artist = '';
  		}
  		$this->printSongs($songs, $artist);
  	}
  
  	public function songs($params) {
  		if (!$this->checkAuth($params)) {
  			$this->error(401, 'Invalid Login');
  		}
  		$filter = isset($params['filter']) ? $params['filter'] : '';
  		$exact = isset($params['exact']) ? ($params['exact'] == 'true') : false;
  		$songs = $this->collection->getSongs(0, 0, $filter, $exact);
  		$this->printSongs($songs);
  	}
  
  	public function song($params) {
  		if (!$this->checkAuth($params)) {
  			$this->error(401, 'Invalid Login');
  		}
  		if ($song = $this->collection->getSong($params['filter'])) {
  			$this->printSongs(array($song));
  		}
  	}
  
  	public function play($params) {
  		if (!$this->checkAuth($params)) {
  			$this->error(401, 'Invalid Login');
  		}
  		if ($song = $this->collection->getSong($params['song'])) {
  			\OC_Util::setupFS($song["song_user"]);
  
  			header('Content-type: ' . \OC_Filesystem::getMimeType($song['song_path']));
  			\OC_Filesystem::readfile($song['song_path']);
  		}
  	}
  
  	public function url_to_song($params) {
  		if (!$this->checkAuth($params)) {
  			$this->error(401, 'Invalid Login');
  		}
  		$url = $params['url'];
  		$songId = substr($url, strrpos($url, 'song=') + 5);
  		if ($song = $this->collection->getSong($songId)) {
  			$this->printSongs(array($song));
  		}
  	}
  
  	public function search_songs($params) {
  		if (!$this->checkAuth($params)) {
  			$this->error(401, 'Invalid Login');
  		}
  		$filter = isset($params['filter']) ? $params['filter'] : '';
  		$artists = $this->collection->getArtists($filter);
  		$albums = $this->collection->getAlbums(0, $filter);
  		$songs = $this->collection->getSongs(0, 0, $filter);
  		foreach ($artists as $artist) {
  			$songs = array_merge($songs, $this->collection->getSongs($artist['artist_id']));
  		}
  		foreach ($albums as $album) {
  			$songs = array_merge($songs, $this->collection->getSongs($album['album_artist'], $album['album_id']));
  		}
  		$this->printSongs($songs);
  	}
  }
  
  /**
   * From http://dk1.php.net/manual/en/function.htmlentities.php#106535
   */
  function get_xml_entity_at_index_0($CHAR) {
  	if (!is_string($CHAR[0]) || (strlen($CHAR[0]) > 1)) {
  		die("function: 'get_xml_entity_at_index_0' requires data type: 'char' (single character). '{$CHAR[0]}' does not match this type.");
  	}
  	switch ($CHAR[0]) {
  		case "'":
  		case '"':
  		case '&':
  		case '<':
  		case '>':
  			return htmlspecialchars($CHAR[0], ENT_QUOTES);
  			break;
  		default:
  			return numeric_entity_4_char($CHAR[0]);
  			break;
  	}
  }
  
  function numeric_entity_4_char($char) {
  	return "&#" . str_pad(ord($char), 3, '0', STR_PAD_LEFT) . ";";
  }
  
  function xmlentities($string) {
  	$not_in_list = "A-Z0-9a-z\s_-";
  	return preg_replace_callback("/[^{$not_in_list}]/", '\OCA\Media\get_xml_entity_at_index_0', $string);
  }