js/mpc.js

   1 // Written by Mike Frysinger <vapier@gmail.com>.  Released into the public domain.  Suck it.
   2
   3 function Mpc(socket, cb_update_state, debug_enabled) {
   4         this._socket = socket;
   5         this._cb_update_state = cb_update_state;
   6         this._debug_enabled = debug_enabled;
   7         this._queue = ['init'];
   8         this.state = {};
   9 }
  10
  11 Mpc.prototype.log = function(msg, obj) {
  12         if (this._debug_enabled)
  13                 console.log('mpc: ' + msg, obj);
  14 }
  15
  16 Mpc.prototype.set_debug = function(val) {
  17         this._debug_enabled = val;
  18 }
  19
  20 Mpc.prototype.send = function(msg) {
  21         var _this = this;
  22         this._queue.push(msg);
  23         this._socket.send(msg, function(x) {
  24                 _this.log('send: ' + msg + ':', x);
  25         });
  26 }
  27
  28 Mpc.prototype.recv_msg = function(lines) {
  29         curr = this._queue.shift();
  30         this.log('recv: [' + curr + ']:', lines.join('\n'));
  31         curr = curr.split(' ');
  32
  33         switch (curr[0]) {
  34         // Needs to return a list of dicts (see above for dicts).
  35         //case 'playlistinfo':
  36         case 'currentsong':
  37         case 'stats':
  38         case 'status':
  39                 state = {};
  40                 lines.forEach(function(line) {
  41                         i = line.indexOf(':');
  42                         if (i == -1)
  43                                 return; // Ignores the OK line
  44                         key = line.substr(0, i);
  45                         val = line.substr(i + 2);
  46                         state[key] = val;
  47                 });
  48                 this.state = state;
  49                 this._cb_update_state(state);
  50                 break;
  51         default:
  52                 this._cb_update_state(lines, curr);
  53                 break;
  54         }
  55 }
  56
  57 Mpc.prototype.recv = function(msg) {
  58         /* We can get back a bunch of responses in a row, so parse them out */
  59         /* XXX: Do we have to handle partial reads ?  like long playlists ... */
  60         lines = msg.split('\n');
  61         var i = 0;
  62         while (i < lines.length) {
  63                 if (lines[i] == 'OK' || lines[i].substr(0, 3) == 'OK ') {
  64                         this.recv_msg(lines.splice(0, i + 1));
  65                         i = 0;
  66                 } else
  67                         ++i;
  68         }
  69 }
  70
  71 /*
  72  * Command generator helpers.
  73  */
  74
  75 Mpc.__make_send_void = function(cmd) {
  76         return function() { this.send(cmd); }
  77 }
  78
  79 Mpc.__make_send_arg1 = function(cmd) {
  80         return function(a1) {
  81                 if (a1 === undefined)
  82                         this.log(cmd + ': function requires one argument');
  83                 else
  84                         this.send(cmd + ' ' + a1);
  85         }
  86 }
  87
  88 Mpc.__make_send_arg2 = function(cmd) {
  89         return function(a1, a2) {
  90                 if (a1 === undefined || a2 === undefined)
  91                         this.log(cmd + ': function requires two arguments');
  92                 else
  93                         this.send(cmd + ' ' + a1 + ' ' + a2);
  94         }
  95 }
  96
  97 Mpc.__make_send_opt = function(cmd) {
  98         return function(arg) {
  99                 if (arg === undefined)
 100                         arg = '';
 101                 this.send(cmd + ' ' + arg);
 102         };
 103 }
 104
 105 Mpc.__make_send_range = function(cmd, min, max, def) {
 106         return function(arg) {
 107                 if (arg === undefined)
 108                         arg = def;
 109                 if (arg >= min && arg <= max)
 110                         this.send(cmd + ' ' + arg);
 111                 else
 112                         this.log(cmd + ': arg must be [' + min + ',' + max + '] but got "' + arg + '"');
 113         };
 114 }
 115
 116 /*
 117  * Querying MPD's status
 118  * http://www.musicpd.org/doc/protocol/ch03.html#idp118752
 119  */
 120
 121 // clearerror
 122 Mpc.prototype.clearerror          = Mpc.__make_send_void('clearerror');
 123 // currentsong
 124 Mpc.prototype.currentsong         = Mpc.__make_send_void('currentsong');
 125 // idle [SUBSYSTEMS...]
 126 // TODO
 127 // status
 128 Mpc.prototype.status              = Mpc.__make_send_void('status');
 129 // stats
 130 Mpc.prototype.stats               = Mpc.__make_send_void('stats');
 131
 132 /*
 133  * Playback options
 134  * http://www.musicpd.org/doc/protocol/ch03s02.html
 135  */
 136
 137 // consume {STATE}
 138 Mpc.prototype.consume             = Mpc.__make_send_range('consume', 0, 1, 1);
 139 // crossfade {SECONDS}
 140 Mpc.prototype.crossfade           = Mpc.__make_send_arg1('crossfade');
 141 // mixrampdb {deciBels}
 142 Mpc.prototype.mixrampdb           = Mpc.__make_send_arg1('mixrampdb');
 143 // mixrampdelay {SECONDS|nan}
 144 // Note: Probably should handle javascript NaN here.
 145 Mpc.prototype.mixrampdelay        = Mpc.__make_send_arg1('mixrampdelay');
 146 // random {STATE}
 147 Mpc.prototype.random              = Mpc.__make_send_range('random', 0, 1, 1);
 148 // repeat {STATE}
 149 Mpc.prototype.repeat              = Mpc.__make_send_range('repeat', 0, 1, 1);
 150 // setvol {VOL}
 151 Mpc.prototype.setvol              = Mpc.__make_send_range('setvol', 0, 100);
 152 // single {STATE}
 153 Mpc.prototype.single              = Mpc.__make_send_range('single', 0, 1, 1);
 154 // replay_gain_mode {MODE}
 155 Mpc.prototype.replay_gain_mode    = Mpc.__make_send_arg1('replay_gain_mode');
 156 // replay_gain_status
 157
 158 /*
 159  * Controlling playback
 160  * http://www.musicpd.org/doc/protocol/ch03s03.html
 161  */
 162
 163 // next
 164 Mpc.prototype.next                = Mpc.__make_send_void('next');
 165 // pause {PAUSE}
 166 Mpc.prototype.pause               = Mpc.__make_send_range('pause', 0, 1, 1);
 167 // play [SONGPOS]
 168 Mpc.prototype.play                = Mpc.__make_send_opt('play');
 169 // playid [SONGID]
 170 Mpc.prototype.playid              = Mpc.__make_send_opt('playid');
 171 // previous
 172 Mpc.prototype.previous            = Mpc.__make_send_void('previous');
 173 // seek {SONGPOS} {TIME}
 174 Mpc.prototype.seek                = Mpc.__make_send_arg2('seek');
 175 // seekid {SONGID} {TIME}
 176 Mpc.prototype.seekid              = Mpc.__make_send_arg2('seekid');
 177 // seekcur {TIME}
 178 Mpc.prototype.seekcur             = Mpc.__make_send_arg1('seek');
 179 // stop
 180 Mpc.prototype.stop                = Mpc.__make_send_void('stop');
 181
 182 /*
 183  * Connection settings
 184  * http://www.musicpd.org/doc/protocol/ch03s08.html
 185  */
 186
 187 // close
 188 Mpc.prototype.close               = Mpc.__make_send_void('close');
 189 // kill
 190 Mpc.prototype.kill                = Mpc.__make_send_void('kill');
 191 // password {PASSWORD}
 192 Mpc.prototype.password            = Mpc.__make_send_arg1('password');
 193 // ping
 194 Mpc.prototype.ping                = Mpc.__make_send_void('ping');