ampache/lib/class/broadcast_server.class.php

<?php
/* vim:set softtabstop=4 shiftwidth=4 expandtab: */
/**
 *
 * LICENSE: GNU General Public License, version 2 (GPLv2)
 * Copyright 2001 - 2013 Ampache.org
 *
 * 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.
 *
 */

use Ratchet\MessageComponentInterface;
use Ratchet\ConnectionInterface;

class Broadcast_Server implements MessageComponentInterface
{
    const BROADCAST_SONG = "SONG";
    const BROADCAST_SONG_POSITION = "SONG_POSITION";
    const BROADCAST_PLAYER_PLAY = "PLAYER_PLAY";
    const BROADCAST_REGISTER_BROADCAST = "REGISTER_BROADCAST";
    const BROADCAST_REGISTER_LISTENER = "REGISTER_LISTENER";
    const BROADCAST_ENDED = "ENDED";
    const BROADCAST_INFO = "INFO";
    const BROADCAST_NB_LISTENERS = "NB_LISTENERS";

    protected $clients;
    protected $listeners;
    protected $broadcasters;

    public function __construct()
    {
        $this->clients = new \SplObjectStorage;
    }

    public function onOpen(ConnectionInterface $conn)
    {
        $this->clients->attach($conn);
    }

    public function onMessage(ConnectionInterface $from, $msg)
    {
        $commands = explode(';', $msg);
        foreach ($commands as $command) {
            $cmdinfo = explode('=', $msg, 2);

            if (count($cmdinfo) == 2) {
                switch ($cmdinfo[0]) {
                    case self::BROADCAST_SONG:
                        $this->notifySong($from, $cmdinfo[1]);
                    break;
                    case self::BROADCAST_SONG_POSITION:
                        $this->notifySongPosition($from, $cmdinfo[1]);
                    break;
                    case self::BROADCAST_PLAYER_PLAY:
                        $this->notifyPlayerPlay($from, $cmdinfo[1]);
                    break;
                    case self::BROADCAST_ENDED:
                        $this->notifyEnded($from);
                    break;
                    case self::BROADCAST_REGISTER_BROADCAST:
                        $this->registerBroadcast($from, $cmdinfo[1]);
                    break;
                    case self::BROADCAST_REGISTER_LISTENER:
                        $this->registerListener($from, $cmdinfo[1]);
                    break;
                }
            }
        }
    }

    protected function notifySong($from, $song_id)
    {
        if ($this->isBroadcaster($from)) {
            $broadcast = $broadcasters[$from];
            $clients = $this->getListeners($broadcast);
            $this->broadcastMessage($clients, self::BROADCAST_SONG, $song_id);
        } else {
            debug_event('broadcast', 'Action unauthorized.', '3');
        }
    }

    protected function notifySongPosition($from, $song_position)
    {
        if ($this->isBroadcaster($from)) {
            $broadcast = $broadcasters[$from];
            $clients = $this->getListeners($broadcast);
            $this->broadcastMessage($clients, self::BROADCAST_SONG_POSITION, $song_position);
        } else {
            debug_event('broadcast', 'Action unauthorized.', '3');
        }
    }

    protected function notifyPlayerPlay($from, $play)
    {
        if ($this->isBroadcaster($from)) {
            $broadcast = $broadcasters[$from];
            $clients = $this->getListeners($broadcast);
            $this->broadcastMessage($clients, self::BROADCAST_PLAYER_PLAY, $play);
        } else {
            debug_event('broadcast', 'Action unauthorized.', '3');
        }
    }

    protected function registerBroadcast($from, $broadcast_key)
    {
        $broadcast = Broadcast::get_broadcast($broadcast_key);
        if ($broadcast) {
            $broadcasters[$from] = $broadcast;
            $listeners[$broadcast] = array();
        }
    }

    protected function unregisterBroadcast($conn)
    {
        $broadcast = $broadcasters[$conn];
        $clients = $this->getListeners($broadcast);
        $this->broadcastMessage($clients, self::BROADCAST_ENDED);

        unset($listeners[$broadcast]);
        unset($broadcasters[$conn]);
    }

    protected function getRunningBroadcast($broadcast_id)
    {
        $broadcast = null;
        foreach ($broadcasters as $conn => $br) {
            if ($br->id == $broadcast_id) {
                $broadcast = $br;
                exit;
            }
        }
        return $broadcast;
    }

    protected function registerListener($from, $broadcast_id)
    {
        $broadcast = $this->getRunningBroadcast();
        $listeners[$broadcast][] = $from;
    }

    protected function unregisterListener($conn)
    {
        foreach ($listeners as $broadcast => $brlisteners) {
            $lindex = array_search($brlisteners, $conn);
            if ($lindex) {
                unset($brlisteners[$lindex]);
                break;
            }
        }
    }

    protected function notifyNbListeners($broadcast)
    {
        $broadcaster = array_search(broadcasters, $broadcast);
        $clients = $listeners[$broadcast];
        $clients[] = $broadcaster;
        $this->broadcastMessage($clients, self::BROADCAST_NB_LISTENERS, count($listeners[$broadcast]));
    }

    protected function getListeners($broadcast)
    {
        return $listeners[$broadcast];
    }

    protected function isBroadcaster($conn)
    {
        return bool(array_search($conn, $broadcasters));
    }

    protected function broadcastMessage($clients, $cmd, $value='')
    {
        $msg = $cmd . '=' . $value . ';';
        foreach ($clients as $client) {
            $client->send($msg);
        }
    }

    public function onClose(ConnectionInterface $conn)
    {
        if ($this->isBroadcaster($conn)) {
            $this->unregisterBroadcast($conn);
        } else {
            $this->unregisterListener($conn);
        }

        $this->clients->detach($conn);
    }

    public function onError(ConnectionInterface $conn, \Exception $e)
    {
        $conn->close();
    }

    public static function get_address()
    {
        $websocket_address = AmpConfig::get('websocket_address');
        if (empty($websocket_address)) {
            $websocket_address = 'ws://' . $_SERVER['HTTP_HOST'] . ':8100';
        }

        return $websocket_address . '/broadcast';
    }

} // end of broadcast_server class