<?php

/**
 * Action servlet (play, pause, etc.)
 *
 * Greyhound - real web management for Amarok
 * Copyright (C) 2008 Dan Fuhry
 *
 * This program is Free Software; you can redistribute and/or modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
 *
 * 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 details.
 */

status('initializing Services_JSON');
$json = new Services_JSON(SERVICES_JSON_LOOSE_TYPE);

// keep track of playlist refresh
$playlist_last_refresh = time();

/**
 * Terminate a request with an error string formatted as JSON.
 * @param string Error message
 */

function json_die($msg)
{
  global $json;
  echo $json->encode(array(
      'mode' => 'error',
      'error' => $msg
    ));
  return true;
}

function ajax_request_handler($httpd, $socket)
{
  global $playlist, $mime_types, $json, $allowcontrol;
  global $use_auth, $auth_data;
  
  if ( $use_auth )
  {
    if ( !isset($_SERVER['PHP_AUTH_USER']) )
    {
      $httpd->header('WWW-Authenticate: basic');
      $httpd->send_http_error($socket, 401, "A username and password are required to access this resource. Either you did not specify a username and password, or the supplied credentials were incorrect.");
      return true;
    }
    if ( !isset($auth_data[$_SERVER['PHP_AUTH_USER']]) )
    {
      $httpd->header('WWW-Authenticate: basic');
      $httpd->send_http_error($socket, 401, "A username and password are required to access this resource. Either you did not specify a username and password, or the supplied credentials were incorrect.");
      return true;
    }
    else if ( $_SERVER['PHP_AUTH_PW'] !== $auth_data[$_SERVER['PHP_AUTH_USER']] )
    {
      $httpd->header('WWW-Authenticate: basic');
      $httpd->send_http_error($socket, 401, "A username and password are required to access this resource. Either you did not specify a username and password, or the supplied credentials were incorrect.");
      return true;
    }
  }
  
  // Set content type
  $httpd->header("Content-type: {$mime_types['js']}");
  
  // get PATH_INFO
  $pathinfo = @substr(@substr($_SERVER['REQUEST_URI'], 1), @strpos(@substr($_SERVER['REQUEST_URI'], 1), '/')+1);
  if ( empty($pathinfo) )
  {
    return json_die('No action specified on URI');
  }
  
  $params = explode('/', $pathinfo);
  $action =& $params[0];
  switch ( $action )
  {
    case 'stop':
    case 'next':
    case 'prev':
      if ( !$allowcontrol )
        return false;
      echo dcop_action('player', $action);
      break;
    case 'play':
      if ( !$allowcontrol )
        return false;
      echo dcop_action('player', 'playPause');
      break;
    case 'jump':
      if ( !$allowcontrol )
        return false;
      $tid =& $params[1];
      if ( !preg_match('/^[0-9]+$/', $tid) )
      {
        return json_die('Invalid track ID');
      }
      $tid = intval($tid);
      dcop_action('playlist', "playByIndex $tid");
      $return = array(
        'current_track_length' => $playlist[$tid]['length_int'],
        'current_track_pos' => 0,
        'current_track_title' => $playlist[$tid]['title'],
        'current_track_album' => $playlist[$tid]['album'],
        'current_track_artist' => $playlist[$tid]['artist']
      );
      echo $json->encode($return);
      break;
    case 'volume':
      if ( !$allowcontrol )
        return false;
      $volume =& $params[1];
      if ( !preg_match('/^[0-9]+$/', $volume) )
      {
        return json_die('Invalid track ID');
      }
      $volume = intval($volume);
      dcop_action('player', "setVolume $volume");
      $return = array(
        'volume' => $volume
        );
      echo $json->encode($return);
      break;
    case 'seek':
      if ( !$allowcontrol )
        return false;
      $pos =& $params[1];
      if ( !preg_match('/^[0-9]+$/', $pos) )
      {
        return json_die('Invalid track ID');
      }
      $pos = intval($pos);
      dcop_action('player', "seek $pos");
      
      break;
    case 'refresh':
      global $playlist_last_refresh, $playlist, $playlist_last_md5;
      if ( $playlist_last_refresh + 60 < time() )
      {
        rebuild_playlist();
      }
      $current_track = dcop_action('playlist', 'getActiveIndex');
      $current_time = dcop_action('player', 'trackCurrentTime');
      $is_playing = dcop_action('player', 'isPlaying');
      $return = array(
          'is_playing' => $is_playing,
          'is_paused' => $current_time > 0 && !$is_playing,
          'current_track' => $current_track,
          'volume' => dcop_action('player', 'getVolume'),
          // include the MD5 of the playlist so that if it changes, the
          // client can refresh (otherwise things get madly corrupted)
          'playlist_hash' => $playlist_last_md5,
          'current_track_title' => false,
          'current_track_album' => false,
          'current_track_artist' => false
        );
      if ( isset($playlist[$current_track]) )
      {
        $return['current_track_length'] = $playlist[$current_track]['length_int'];
        $return['current_track_pos'] = $current_time;
        $return['current_track_title'] = $playlist[$current_track]['title'];
        $return['current_track_artist'] = $playlist[$current_track]['artist'];
        $return['current_track_album'] = $playlist[$current_track]['album'];
      }
      echo $json->encode($return);
      break;
    default:
      return json_die("Undefined action: $action");
  }
}