Make playlist downloads idempotent

Should fix the VLC plugin, as well as allow direct use of an Ampache
site on Android devices.

First, split the Stream class into an instantiable class that does the
playlist wrangling and a static class that handles the streaming stuff.

How does this work? Well, stream.php does its fancy stuff like
gathering the media IDs and clearing the playlist, but instead
of generating the playlist file there we use the Stream_Playlist
class to store the list of URLs in the database, then redirect to
play/index.php to create the actual download (there are some magic
playlist types like localplay that don't need to redirect.)
The playlist will be cached as long as that stream session is active, so
it can be downloaded multiple times and by clients that don't share the
browser's cookie cache.

Clean up the playlist generation by reducing copypasta.

1 files changed, 451 insertions, 0 deletions

diff --git a/lib/class/stream_playlist.class.php b/lib/class/stream_playlist.class.php
new file mode 100644
index 00000000..1a34f0b9
--- /dev/null
+++ b/lib/class/stream_playlist.class.php
@@ -0,0 +1,451 @@
+<?php
+/* vim:set tabstop=8 softtabstop=8 shiftwidth=8 noexpandtab: */
+/**
+ *
+ * LICENSE: GNU General Public License, version 2 (GPLv2)
+ * Copyright (c) 2001 - 2011 Ampache.org All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License v2
+ * 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ */
+
+/**
+ * Stream_Playlist Class
+ *
+ * This class is used to generate the Playlists and pass them on
+ * With Localplay this actually just sends the commands to the localplay
+ * module in question.
+ */
+
+class Stream_Playlist {
+
+	public $id; 
+	public $urls  = array();
+	public $user;
+
+	/**
+	 * Stream_Playlist constructor
+	 * If an ID is passed, it should be a stream session ID. 
+	 */
+	public function __construct($id = null) {
+
+		if($id) {
+			Stream::set_session($id);
+		}
+
+		$this->id = Dba::escape(Stream::get_session());
+
+		if (!Stream::session_exists($this->id)) {
+			debug_event('stream_playlist', 'Stream::session_exists failed', 2);
+			return false;
+		}
+
+		$this->user = intval($GLOBALS['user']->id);
+
+		$sql = "SELECT * FROM `stream_playlist` WHERE `sid`='" .
+			$this->id . "' ORDER BY `id`";
+
+		$db_results = Dba::read($sql);
+		
+		while ($row = Dba::fetch_assoc($db_results)) {
+			$this->urls[] = new Stream_URL($row);
+		}
+
+		return true;
+	}
+
+	private function _add_url($url) {
+		$this->urls[] = $url;
+
+		$sql = 'INSERT INTO `stream_playlist` ';
+
+		$fields[] = '`sid`';
+		$values[] = Dba::escape($this->id);
+
+		foreach ($url->properties as $field) {
+			if ($url->$field) {
+				$fields[] = '`' . $field . '`';
+				$values[] = Dba::escape($url->$field);
+			}
+		}
+		$sql .= '(' . implode(', ', $fields) . ') ';
+		$sql .= "VALUES('" . implode("', '", $values) . "')";
+
+		return Dba::write($sql);
+	}
+
+	public static function clean() {
+		$sql = 'DELETE FROM `stream_playlist` ' .
+			'USING `stream_playlist` LEFT JOIN `session_stream` ' .
+			'ON `session_stream`.`id`=`stream_playlist`.`sid` ' .
+			'WHERE `session_stream`.`id` IS NULL';
+		return Dba::write($sql);
+	}
+
+	/**
+	 * _media_to_urlarray
+	 * Formats the URL and media information and adds it to the object
+	 */
+	private static function _media_to_urlarray($media) {
+		$urls = array();
+		foreach($media as $medium) {
+			debug_event('stream_playlist', 'Adding ' . json_encode($media), 5);
+			$url = array();
+
+			$type = $medium['object_type'];
+			$array['type'] = $type;
+
+			$object = new $type($medium['object_id']);
+			$object->format();
+			//FIXME: play_url shouldn't be static
+			$url['url'] = $type::play_url($object->id);
+
+			// Set a default which can be overridden
+			$url['author'] = 'Ampache';
+			$url['time'] = $object->time;
+			switch($type) {
+				case 'song':
+					$url['title'] = $object->title;
+					$url['author'] = $object->f_artist_full;
+					$url['info_url'] = $object->f_link;
+					$url['image_url'] = Art::url($object->album, 'album');
+					$url['album'] = $object->f_album_full;
+				break;
+				case 'video':
+					$url['title'] = 'Video - ' . $object->title;
+					$url['author'] = $object->f_artist_full;
+				break;
+				case 'radio':
+					$url['title'] = 'Radio - ' . $object->name .
+						' [' . $object->frequency .
+						'] (' . $object->site_url . ')';
+				break;
+				case 'random':
+					$url['title'] = 'Random URL';
+				break;
+				default:
+					$url['title'] = 'URL-Add';
+					$url['time'] = -1;
+				break;
+			}
+
+			$urls[] = new Stream_URL($url);
+		}
+
+		return $urls;
+	}
+
+	public function generate_playlist($type, $redirect = false) {
+
+		if (!count($this->urls)) {
+			debug_event('stream_playlist', 'Error: Empty URL array for ' . $this->id, 2);
+			return false;
+		}
+
+		debug_event('stream_playlist', 'generating a ' . $type, 5);
+
+		$ext = $type;
+		switch($type) {
+			case 'democratic':
+			case 'localplay':
+			case 'xspf_player':
+				// These are valid, but witchy
+				$redirect = false;
+				unset($ext);
+			break;
+			case 'asx':
+				$ct = 'video/x-ms-wmv';
+			break;
+			case 'pls':
+				$ct = 'audio/x-scpls';
+			break;
+			case 'ram':
+				$ct = 'audio/x-pn-realaudio ram';
+			break;
+			case 'simple_m3u':
+				$ext = 'm3u';
+				$ct = 'audio/x-mpegurl';
+			break;
+			case 'xspf':
+				$ct = 'application/xspf+xml';
+			break;
+			case 'm3u':
+			default:
+				// Assume M3U if the pooch is screwed
+				$ext = $type = 'm3u';
+				$ct = 'audio/x-mpegurl';
+			break;
+		}
+
+		if ($redirect) {
+			// Our ID is the SID, so we always want to include it
+			Config::set('require_session', true, true);
+			header('Location: ' . Stream::get_base_url() . 'uid=' . scrub_out($this->user) . '&type=playlist&playlist_type=' . scrub_out($type));
+			exit;
+		}
+
+		if (isset($ext)) {
+			header('Cache-control: public');
+			header('Content-Disposition: filename=ampache_playlist.' . $ext);
+			header('Content-Type: ' . $ct . ';');
+		}
+
+		$this->{'create_' . $type}();
+	}
+
+	/**
+	 * add
+	 * Adds an array of media
+	 */
+	public function add($media = array()) {
+		$urls = $this->_media_to_urlarray($media);
+		foreach ($urls as $url) {
+			$this->_add_url($url);
+		}
+	}
+
+	/**
+	 * add_urls
+	 * Add an array of urls. This is used for things that aren't coming
+	 * from media objects
+	 */
+	public function add_urls($urls = array()) {
+
+		if (!is_array($urls)) { return false; }
+
+		foreach ($urls as $url) {
+			$this->_add_url(new Stream_URL(array(
+				'url' => $url,
+				'title' => 'URL-Add',
+				'author' => 'Ampache',
+				'time' => '-1'
+			)));
+		}
+	}
+
+	/**
+	 * create_simplem3u
+	 * this creates a simple m3u without any of the extended information
+	 */
+	public function create_simple_m3u() {
+
+		foreach ($this->urls as $url) {
+			echo $url->url . "\n";
+		}
+
+	} // simple_m3u
+
+	/**
+	 * create_m3u
+	 * creates an m3u file, this includes the EXTINFO and as such can be
+	 * large with very long playlsits
+	 */
+	public function create_m3u() {
+
+		echo "#EXTM3U\n";
+
+		foreach ($this->urls as $url) {
+			echo '#EXTINF:' . $url->time, ',' . $url->author .
+				' - ' . $url->title . "\n";
+			echo $url->url . "\n";
+		}
+
+	} // create_m3u
+
+	/**
+ 	 * create_pls
+	 */
+	public function create_pls() {
+
+		echo "[playlist]\n";
+		echo 'NumberOfEntries=' . count($this->urls) . "\n";
+		foreach ($this->urls as $url) {
+			$i++;
+			echo 'File' . $i . '='. $url->url . "\n";
+			echo 'Title' . $i . '=' . $url->author . ' - ' .
+				$url->title . "\n";
+			echo 'Length' . $i . '=' . $url->time . "\n";
+		}
+
+		echo "Version=2\n";
+	} // create_pls
+
+	/**
+	 * create_asx
+	 * This should really only be used if all of the content is ASF files.
+	 */
+	public function create_asx() {
+
+		echo '<ASX version = "3.0" BANNERBAR="AUTO">' . "\n";
+		echo "<TITLE>Ampache ASX Playlist</TITLE>";
+
+		foreach ($this->urls as $url) {
+			echo "<ENTRY>\n";
+			echo '<TITLE>' . $url->title . "</TITLE>\n";
+			echo '<AUTHOR>' . $url->author . "</AUTHOR>\n";
+			echo "\t\t" . '<DURATION VALUE="00:00:' . $url->time . '" />' . "\n";
+			echo "\t\t" . '<PARAM NAME="Album" Value="' . $url->album . '" />' . "\n";
+			echo "\t\t" . '<PARAM NAME="Composer" Value="' . $url->author . '" />' . "\n";
+			echo "\t\t" . '<PARAM NAME="Prebuffer" Value="false" />' . "\n";
+			echo '<REF HREF = "' . $url->url . '" />' . "\n";
+			echo "</ENTRY>\n";
+		}
+
+		echo "</ASX>\n";
+
+	} // create_asx
+
+	/**
+	 * create_xspf
+	 */
+	public function create_xspf() {
+
+		foreach ($this->urls as $url) {
+			$xml = array();
+
+			$xml['track'] = array(
+				'title' => $url->title,
+				'creator' => $url->author,
+				// FIXME: regression
+				// video: ['meta'] = array('attribute'=>'rel="provider"','value'=>'video')
+				'duration' => $url->time * 1000,
+				'location' => $url->url,
+				'identifier' => $url->url
+			);
+			if ($url->info_url) {
+				$xml['track']['info'] = $url->info_url;
+			}
+			if ($url->image_url) {
+				$xml['track']['image'] = $url->image_url;
+			}
+			if ($url->album) {
+				$xml['track']['album'] = $url->album;
+			}
+
+			$result .= xmlData::keyed_array($xml, true);
+
+		} // end foreach
+
+		xmlData::set_type('xspf');
+		echo xmlData::header();
+		echo $result;
+		echo xmlData::footer();
+
+	} // create_xspf
+
+	/**
+	 * create_xspf_player
+	 * Due to the fact that this is an integrated player (flash) we actually
+	 * have to do a little 'cheating' to make this work.
+	 * We are going to take advantage of tmp_playlists to do all of this
+	 * hotness
+	 */
+	public function create_xspf_player() {
+		debug_event('stream_playlist', 'Creating XSPF player', 5);
+		/* Build the extra info we need to have it pass */
+		$play_info = "?action=show&tmpplaylist_id=" . $GLOBALS['user']->playlist->id;
+
+		// start ugly evil javascript code
+		//FIXME: This needs to go in a template, here for now though
+		//FIXME: This preference doesn't even exists, we'll eventually
+		//FIXME: just make it the default
+		if (Config::get('embed_xspf') == 1 ){
+			header("Location: ".Config::get('web_path')."/index.php?xspf&play_info=".$GLOBALS['user']->playlist->id);
+		}
+		else {
+			echo "<html><head>\n";
+			echo "<title>" . Config::get('site_title') . "</title>\n";
+			echo "<script language=\"javascript\" type=\"text/javascript\">\n";
+			echo "<!-- begin\n";
+			echo "function PlayerPopUp(URL) {\n";
+			// We do a little check here to see if it's a Wii!
+			if (false !== stristr($_SERVER['HTTP_USER_AGENT'], 'Nintendo Wii')) {
+				echo "window.location=URL;\n";
+			}
+			// Else go ahead and do the normal stuff
+			else {
+				echo "window.open(URL, 'XSPF_player', 'width=400,height=170,scrollbars=0,toolbar=0,location=0,directories=0,status=0,resizable=0');\n";
+				echo "window.location = '" .  return_referer() . "';\n";
+				echo "return false;\n";
+			}
+			echo "}\n";
+			echo "// end -->\n";
+			echo "</script>\n";
+			echo "</head>\n";
+
+			echo "<body onLoad=\"javascript:PlayerPopUp('" . Config::get('web_path') . "/modules/flash/xspf_player.php" . $play_info . "')\">\n";
+			echo "</body>\n";
+			echo "</html>\n";
+		}
+	} // create_xspf_player
+
+	/**
+	 * create_localplay
+	 * This calls the Localplay API to add the URLs and then start playback
+	 */
+	public function create_localplay() {
+
+		$localplay = new Localplay(Config::get('localplay_controller'));
+		$localplay->connect();
+		foreach ($this->urls as $url) {
+			$localplay->add_url($url);
+		}
+
+		$localplay->play();
+
+	} // create_localplay
+
+	/**
+ 	 * create_democratic
+	 * This 'votes' on the songs it inserts them into
+	 * a tmp_playlist with user of -1 (System)
+	 */
+	public function create_democratic() {
+
+		$democratic = Democratic::get_current_playlist();
+		$democratic->set_parent();
+		$democratic->add_vote($this->media);
+
+	} // create_democratic
+
+	/**
+	 * create_download
+	 * This prompts for a download of the song
+	 */
+	private function create_download() {
+
+		// There should only be one here...
+		if (count($this->urls) != 1) {
+			debug_event('stream_playlist', 'Download called, but $urls contains ' . json_encode($this->urls), 2);
+		}
+
+		// Header redirect baby!
+		$url = current($this->urls);
+		header('Location: ' . $url->url . '&action=download');
+		exit;
+	} //create_download
+
+	/**
+	 * create_ram
+	 *this functions creates a RAM file for use by Real Player
+	 */
+	public function create_ram() {
+		foreach ($this->urls as $url) {
+			echo $url->url . "\n";
+		}
+	} // create_ram
+
+}
+
+?>