<?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.
 *
 */

class scrobbler {

    public $error_msg;
    public $username;
    public $password;
    public $challenge;
    public $submit_host;
    public $submit_port;
    public $submit_url;
    public $queued_tracks;
    public $reset_handshake = false;
    public $scrobble_host = 'post.audioscrobbler.com';

    /**
     * Constructor
     * This is the constructer it takes a username and password
     */
    public function __construct($username, $password,$host='',$port='',$url='',$challenge='',$scrobble_host='') {

        $this->error_msg = '';
        $this->username = trim($username);
        $this->password = trim($password);
        $this->challenge = $challenge;
        $this->submit_host = $host;
        $this->submit_port = $port;
        $this->submit_url = $url;
        $this->queued_tracks = array();
        if ($scrobble_host) { $this->scrobble_host = $scrobble_host; }

    } // scrobbler

    /**
     * get_error_msg
     */
    public function get_error_msg() {

        return $this->error_msg;

    } // get_error_msg

    /**
     * get_queue_count
     */
    public function get_queue_count() {

        return count($this->queued_tracks);

    } // get_queue_count

    /**
     * handshake
     * This does a handshake with the audioscrobber server it doesn't pass the password, but
     * it does pass the username and has a 10 second timeout
     */
    public function handshake() {

        $as_socket = fsockopen($this->scrobble_host, 80, $errno, $errstr, 2);
        if(!$as_socket) {
            $this->error_msg = $errstr;
            return false;
        }

        $username    = rawurlencode($this->username);
        $timestamp    = time();
        $auth_token    = rawurlencode(md5($this->password . $timestamp));

        $get_string = "GET /?hs=true&p=1.2&c=apa&v=0.1&u=$username&t=$timestamp&a=$auth_token HTTP/1.1\r\n";

        fwrite($as_socket, $get_string);
        fwrite($as_socket, "Host: $this->scrobble_host\r\n");
        fwrite($as_socket, "Accept: */*\r\n\r\n");

        $buffer = '';
        while(!feof($as_socket)) {
            $buffer .= fread($as_socket, 4096);
        }
        fclose($as_socket);
        $split_response = preg_split("/\r\n\r\n/", $buffer);
        if(!isset($split_response[1])) {
            $this->error_msg = 'Did not receive a valid response';
            return false;
        }
        $response = explode("\n", $split_response[1]);

        // Handle the fact Libre.FM has extranious values at the start of it's handshake response
        if(is_numeric(trim($response['0']))) { 
            array_shift($response); 
            debug_event('SCROBBLER','Junk in handshake, removing first line',1); 
        } 
        if(substr($response[0], 0, 6) == 'FAILED') {
            $this->error_msg = substr($response[0], 7);
            return false;
        }
        if(substr($response[0], 0, 7) == 'BADUSER') {
            $this->error_msg = 'Invalid Username';
            return false;
        }
        if(substr($response[0],0,7) == 'BADTIME') {
            $this->error_msg = 'Your time is too far off from the server, or your PHP timezone is incorrect';
            return false;
        }
        if(substr($response[0], 0, 6) == 'UPDATE') {
            $this->error_msg = 'You need to update your client: '.substr($response[0], 7);
            return false;
        }

        if(preg_match('/http:\/\/([^\/]+)\/(.*)$/', $response[3], $matches)) {
            $host_parts = explode(":",$matches[1]);
            $data['submit_host'] = $host_parts[0];
            $data['submit_port'] = $host_parts[1] ? $host_parts[1] : '80';
            $data['submit_url'] = '/' . $matches[2];
        } else {
            $this->error_msg = "Invalid POST URL returned, unable to continue. Sent:\n$get_string\n----\nReceived:\n" . $buffer .
                "\n---------\nExpected:" . print_r($response, true);
            return false;
        }

        // Remove any extra junk around the challenge
        $data['challenge'] = trim($response[1]); 
        return $data;

    } // handshake

    /**
     * queue_track
     * This queues the LastFM track by storing it in this object, it doesn't actually
     * submit the track or talk to LastFM in anyway, kind of useless for our uses but its
     * here, and that's how it is.
     */
    public function queue_track($artist, $album, $title, $timestamp, $length,$track) {

        if ($length < 30) {
            debug_event('Scrobbler',"Not queuing track, too short",'5');
            return false;
        }

        $newtrack = array();
        $newtrack['artist'] = $artist;
        $newtrack['album'] = $album;
        $newtrack['title'] = $title;
        $newtrack['track'] = $track;
        $newtrack['length'] = $length;
        $newtrack['time'] = $timestamp;

        $this->queued_tracks[$timestamp] = $newtrack;
        return true;

    } // queue_track

    /**
     * submit_tracks
     * This actually talks to LastFM submiting the tracks that are queued up. It
     * passed the md5'd password combinted with the challenge, which is then md5'd
     */
    public function submit_tracks() {

        // Check and make sure that we've got some queued tracks
        if(!count($this->queued_tracks)) {
            $this->error_msg = "No tracks to submit";
            return false;
        }

        //sort array by timestamp
        ksort($this->queued_tracks);

        // build the query string
        $query_str = 's='.rawurlencode($this->challenge).'&';

        $i = 0;

        foreach($this->queued_tracks as $track) {
            $query_str .= "a[$i]=".rawurlencode($track['artist'])."&t[$i]=".rawurlencode($track['title'])."&b[$i]=".rawurlencode($track['album'])."&";
            $query_str .= "m[$i]=&l[$i]=".rawurlencode($track['length'])."&i[$i]=".rawurlencode($track['time'])."&";
            $query_str .= "n[$i]=" . rawurlencode($track['track']) . "&o[$i]=P&r[$i]=&";
            $i++;
        }

        if (!trim($this->submit_host) || !$this->submit_port) {
            $this->reset_handshake = true;
            return false;
        }

        $as_socket = fsockopen($this->submit_host, intval($this->submit_port), $errno, $errstr, 2);

        if(!$as_socket) {
            $this->error_msg = $errstr;
            $this->reset_handshake = true;
            return false;
        }

        $action = "POST ".$this->submit_url." HTTP/1.0\r\n";
        fwrite($as_socket, $action);
        fwrite($as_socket, "Host: ".$this->submit_host."\r\n");
        fwrite($as_socket, "Accept: */*\r\n");
        fwrite($as_socket, "User-Agent: Ampache/3.6\r\n");
        fwrite($as_socket, "Content-type: application/x-www-form-urlencoded\r\n");
        fwrite($as_socket, "Content-length: ".strlen($query_str)."\r\n\r\n");

        fwrite($as_socket, $query_str."\r\n\r\n");
        // Allow us to debug this
        debug_event('SCROBBLER','Query String:' . $query_str,6); 

        $buffer = '';
        while(!feof($as_socket)) {
            $buffer .= fread($as_socket, 8192);
        }
        fclose($as_socket);

        $split_response = preg_split("/\r\n\r\n/", $buffer);
        if(!isset($split_response[1])) {
            $this->error_msg = 'Did not receive a valid response';
            $this->reset_handshake = true;
            return false;
        }
        $response = explode("\n", $split_response[1]);
        if(!isset($response[0])) {
            $this->error_msg = 'Unknown error submitting tracks'.
                      "\nDebug output:\n".$buffer;
            $this->reset_handshake = true;
            return false;
        }
        if(substr($response[0], 0, 6) == 'FAILED') {
            $this->error_msg = $response[0];
            $this->reset_handshake = true;
            return false;
        }
        if(substr($response[0], 0, 7) == 'BADAUTH') {
            $this->error_msg = 'Invalid username/password (' . trim($response[0]) . ')';
            return false;
        }
        if (substr($response[0],0,10) == 'BADSESSION') {
            $this->error_msg = 'Invalid Session passed (' . trim($response[0]) . ')';
            $this->reset_handshake = true;
            return false;
        }
        if(substr($response[0], 0, 2) != 'OK') {
            $this->error_msg = 'Response Not ok, unknown error'.
                      "\nDebug output:\n".$buffer;
            $this->reset_handshake = true;
            return false;
        }

        return true;

    } // submit_tracks

} // end audioscrobbler class
?>
