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._recv_buffer = [];
   9         this._recv_buffer_last = 0;
  10         this.state = {};
  11 }
  12
  13 Mpc.prototype.log = function(lvl, msg, obj) {
  14         if (this._debug_enabled & lvl)
  15                 console.log('mpc: ' + msg, obj);
  16 }
  17
  18 Mpc.prototype.err = function(msg, obj) {
  19         console.error('mpc: ' + msg, obj);
  20 }
  21
  22 Mpc.prototype.set_debug = function(val) {
  23         this._debug_enabled = val;
  24 }
  25
  26 Mpc.prototype.send = function(msg) {
  27         var _this = this;
  28         this._queue.push(msg);
  29         this._socket.send(msg, function(x) {
  30                 _this.log(0x1, 'send: ' + msg + ':', x);
  31                 if (x.bytesWritten < 0) {
  32                         _this.log(0x1, 'reconnecting...');
  33                         _this._socket.reconnect();
  34                         _this.queue = [msg];
  35                         _this._socket.send(msg);
  36                 }
  37         });
  38 }
  39
  40 Mpc.prototype._parse_result = function(lines) {
  41         var state = {};
  42         var keys = [];
  43         var key, val, i;
  44
  45         lines.forEach(function(line) {
  46                 i = line.indexOf(':');
  47                 if (i == -1)
  48                         return; // Ignores the OK line
  49                 key = line.substr(0, i);
  50                 keys.push(key);
  51                 val = line.substr(i + 2);
  52                 state[key] = val;
  53         });
  54
  55         return {
  56                 'state': state,
  57                 'keys': keys,
  58         };
  59 }
  60
  61 Mpc.prototype.recv_msg = function(lines) {
  62         var state, keys, ret;
  63         var curr = this._queue.shift();
  64         this.log(0x2, 'recv: [' + curr + ']:', lines.join('\n'));
  65         if (lines[0].substr(0, 4) == 'ACK ')
  66                 this.err(curr, lines.join('\n'));
  67         curr = curr.split(' ');
  68
  69         switch (curr[0]) {
  70         case 'playlistinfo':
  71                 var i = 2, playlist = [], song;
  72                 while (i < lines.length) {
  73                         if (lines[i].substr(0, 5) == 'file:') {
  74                                 song = this._parse_result(lines.splice(0, i + 1)).state;
  75                                 playlist = playlist.concat(song);
  76                                 i = 0;
  77                         } else
  78                                 ++i;
  79                 }
  80                 this.state.Playlist = playlist;
  81                 this.state.Playlist.lastUpdate = (new Date()).getTime();
  82                 this._cb_update_state(this.state);
  83                 break;
  84
  85         case 'currentsong':
  86                 this.state.Currentsong = this._parse_result(lines).state;
  87                 this.state.Currentsong.lastUpdate = (new Date()).getTime();
  88                 this._cb_update_state(this.state);
  89                 break;
  90
  91         case 'stats':
  92         case 'status':
  93                 ret = this._parse_result(lines);
  94                 state = ret.state;
  95                 keys = ret.keys;
  96
  97                 // When mpd is stopped, it gives us back crap values for some things.
  98                 if ('state' in state && state.state == 'stop') {
  99                         if ('volume' in state && state.volume == '-1')
 100                                 keys.splice(keys.indexOf('volume'), 1);
 101                 }
 102                 // Now merge the current state with the previous one so that we don't
 103                 // lose information like volume or song position.
 104                 var curr_state = this.state;
 105                 keys.forEach(function(key) {
 106                         curr_state[key] = state[key];
 107                 });
 108
 109                 this._cb_update_state(curr_state);
 110                 break;
 111
 112         default:
 113                 this._cb_update_state(lines, curr);
 114                 break;
 115         }
 116 }
 117
 118 Mpc.prototype.recv = function(msg) {
 119         /* We can get back a bunch of responses in a row, so parse them out */
 120         var lines = this._recv_buffer = this._recv_buffer.concat(msg.split('\n'));
 121         var i = 0;
 122         while (i < lines.length) {
 123                 if (lines[i] == 'OK' || lines[i].substr(0, 3) == 'OK ' ||
 124                     lines[i].substr(0, 4) == 'ACK ') {
 125                         this.recv_msg(lines.splice(0, i + 1));
 126                         i = 0;
 127                 } else
 128                         ++i;
 129         }
 130
 131         if (lines.length && this._recv_buffer_last != lines.length) {
 132                 // Keep sucking in data so long as more exists.
 133                 this._recv_buffer_last = lines.length;
 134                 this._socket.poll();
 135         } else
 136                 this._recv_buffer_last = lines.length;
 137 }
 138
 139 /*
 140  * Command generator helpers.
 141  */
 142
 143 Mpc.__make_send_void = function(cmd) {
 144         return function() { this.send(cmd); }
 145 }
 146
 147 Mpc.__make_send_arg1 = function(cmd) {
 148         return function(a1) {
 149                 if (a1 === undefined)
 150                         this.err(cmd + ': function requires one argument');
 151                 else
 152                         this.send(cmd + ' ' + a1);
 153         }
 154 }
 155
 156 Mpc.__make_send_arg2 = function(cmd) {
 157         return function(a1, a2) {
 158                 if (a1 === undefined || a2 === undefined)
 159                         this.err(cmd + ': function requires two arguments');
 160                 else
 161                         this.send(cmd + ' ' + a1 + ' ' + a2);
 162         }
 163 }
 164
 165 Mpc.__make_send_arg3 = function(cmd) {
 166         return function(a1, a2, a3) {
 167                 if (a1 === undefined || a2 === undefined || a3 == undefined)
 168                         this.err(cmd + ': function requires three arguments');
 169                 else
 170                         this.send(cmd + ' ' + a1 + ' ' + a2 + ' ' + a3);
 171         }
 172 }
 173
 174 Mpc.__make_send_opt = function(cmd) {
 175         return function(arg) {
 176                 if (arg === undefined)
 177                         arg = '';
 178                 this.send(cmd + ' ' + arg);
 179         };
 180 }
 181
 182 Mpc.__make_send_range = function(cmd, min, max, def) {
 183         return function(arg) {
 184                 if (arg === undefined)
 185                         arg = def;
 186                 if (arg >= min && arg <= max)
 187                         this.send(cmd + ' ' + arg);
 188                 else
 189                         this.err(cmd + ': arg must be [' + min + ',' + max + '] but got "' + arg + '"');
 190         };
 191 }
 192
 193 /*
 194  * Querying MPD's status
 195  * http://www.musicpd.org/doc/protocol/ch03.html#idp118752
 196  */
 197
 198 // clearerror
 199 Mpc.prototype.clearerror          = Mpc.__make_send_void('clearerror');
 200 // currentsong
 201 Mpc.prototype.currentsong         = Mpc.__make_send_void('currentsong');
 202 // idle [SUBSYSTEMS...]
 203 // TODO
 204 // status
 205 Mpc.prototype.status              = Mpc.__make_send_void('status');
 206 // stats
 207 Mpc.prototype.stats               = Mpc.__make_send_void('stats');
 208
 209 /*
 210  * Playback options
 211  * http://www.musicpd.org/doc/protocol/ch03s02.html
 212  */
 213
 214 // consume {STATE}
 215 Mpc.prototype.consume             = Mpc.__make_send_range('consume', 0, 1, 1);
 216 // crossfade {SECONDS}
 217 Mpc.prototype.crossfade           = Mpc.__make_send_arg1('crossfade');
 218 // mixrampdb {deciBels}
 219 Mpc.prototype.mixrampdb           = Mpc.__make_send_arg1('mixrampdb');
 220 // mixrampdelay {SECONDS|nan}
 221 // Note: Probably should handle javascript NaN here.
 222 Mpc.prototype.mixrampdelay        = Mpc.__make_send_arg1('mixrampdelay');
 223 // random {STATE}
 224 Mpc.prototype.random              = Mpc.__make_send_range('random', 0, 1, 1);
 225 // repeat {STATE}
 226 Mpc.prototype.repeat              = Mpc.__make_send_range('repeat', 0, 1, 1);
 227 // setvol {VOL}
 228 Mpc.prototype.setvol              = Mpc.__make_send_range('setvol', 0, 100);
 229 // single {STATE}
 230 Mpc.prototype.single              = Mpc.__make_send_range('single', 0, 1, 1);
 231 // replay_gain_mode {MODE}
 232 Mpc.prototype.replay_gain_mode    = Mpc.__make_send_arg1('replay_gain_mode');
 233 // replay_gain_status
 234
 235 /*
 236  * Controlling playback
 237  * http://www.musicpd.org/doc/protocol/ch03s03.html
 238  */
 239
 240 // next
 241 Mpc.prototype.next                = Mpc.__make_send_void('next');
 242 // pause {PAUSE}
 243 Mpc.prototype.pause               = Mpc.__make_send_range('pause', 0, 1, 1);
 244 // play [SONGPOS]
 245 Mpc.prototype.play                = Mpc.__make_send_opt('play');
 246 // playid [SONGID]
 247 Mpc.prototype.playid              = Mpc.__make_send_opt('playid');
 248 // previous
 249 Mpc.prototype.previous            = Mpc.__make_send_void('previous');
 250 // seek {SONGPOS} {TIME}
 251 Mpc.prototype.seek                = Mpc.__make_send_arg2('seek');
 252 // seekid {SONGID} {TIME}
 253 Mpc.prototype.seekid              = Mpc.__make_send_arg2('seekid');
 254 // seekcur {TIME}
 255 Mpc.prototype.seekcur             = Mpc.__make_send_arg1('seekcur');
 256 // stop
 257 Mpc.prototype.stop                = Mpc.__make_send_void('stop');
 258
 259 /*
 260  * The current playlist
 261  * http://www.musicpd.org/doc/protocol/ch03s04.html
 262  */
 263
 264 // add {URI}
 265 Mpc.prototype.add                 = Mpc.__make_send_arg1('add');
 266 // addid {URI} [POSITION]
 267 // TODO: handle position
 268 Mpc.prototype.addid               = Mpc.__make_send_arg1('addid');
 269 // clear
 270 Mpc.prototype.clear               = Mpc.__make_send_void('clear');
 271 // delete [{POS} | {START:END}]
 272 Mpc.prototype.delete              = Mpc.__make_send_arg1('delete');
 273 // deleteid {SONGID}
 274 Mpc.prototype.deleteid            = Mpc.__make_send_arg1('deleteid');
 275 // move [{FROM} | {START:END}] {TO}
 276 Mpc.prototype.move                = Mpc.__make_send_arg2('move');
 277 // moveid {FROM} {TO}
 278 Mpc.prototype.moveid              = Mpc.__make_send_arg2('moveid');
 279 // playlist
 280 Mpc.prototype.playlist            = Mpc.__make_send_void('playlist');
 281 // playlistfind {TAG} {NEEDLE}
 282 Mpc.prototype.playlistfind        = Mpc.__make_send_arg2('playlistfind');
 283 // playlistid {SONGID}
 284 Mpc.prototype.playlistid          = Mpc.__make_send_arg1('playlistid');
 285 // playlistinfo [[SONGPOS] | [START:END]]
 286 Mpc.prototype.playlistinfo        = Mpc.__make_send_opt('playlistinfo');
 287 // playlistsearch {TAG} {NEEDLE}
 288 Mpc.prototype.playlistsearch      = Mpc.__make_send_arg2('playlistsearch');
 289 // plchanges {VERSION}
 290 Mpc.prototype.plchanges           = Mpc.__make_send_arg1('plchanges');
 291 // plchangesposid {VERSION}
 292 Mpc.prototype.plchangesposid      = Mpc.__make_send_arg1('plchangesposid');
 293 // prio {PRIORITY} {START:END...}
 294 Mpc.prototype.prio                = Mpc.__make_send_arg2('prio');
 295 // prioid {PRIORITY} {ID...}
 296 Mpc.prototype.prioid              = Mpc.__make_send_arg2('prioid');
 297 // shuffle [START:END]
 298 Mpc.prototype.shuffle             = Mpc.__make_send_opt('shuffle');
 299 // swap {SONG1} {SONG2}
 300 Mpc.prototype.swap                = Mpc.__make_send_arg2('swap');
 301 // swapid {SONG1} {SONG2}
 302 Mpc.prototype.swapid              = Mpc.__make_send_arg2('swapid');
 303
 304 /*
 305  * Stored playlists
 306  * http://www.musicpd.org/doc/protocol/ch03s05.html
 307  */
 308
 309 // listplaylist {NAME}
 310 Mpc.prototype.listplaylist        = Mpc.__make_send_arg1('listplaylist');
 311 // listplaylistinfo {NAME}
 312 Mpc.prototype.listplaylistinfo    = Mpc.__make_send_arg1('listplaylistinfo');
 313 // listplaylists
 314 Mpc.prototype.listplaylists       = Mpc.__make_send_void('listplaylists');
 315 // load {NAME} [START:END]
 316 // TODO: handle optional start:end
 317 Mpc.prototype.load                = Mpc.__make_send_arg1('load');
 318 // playlistadd {NAME} {URI}
 319 Mpc.prototype.playlistadd         = Mpc.__make_send_arg2('playlistadd');
 320 // playlistclear {NAME}
 321 Mpc.prototype.playlistclear       = Mpc.__make_send_arg1('playlistclear');
 322 // playlistdelete {NAME} {SONGPOS}
 323 Mpc.prototype.playlistdelete      = Mpc.__make_send_arg2('playlistdelete');
 324 // playlistmove {NAME} {SONGID} {SONGPOS}
 325 Mpc.prototype.playlistmove        = Mpc.__make_send_arg3('playlistmove');
 326 // rename {NAME} {NEW_NAME}
 327 Mpc.prototype.rename              = Mpc.__make_send_arg2('rename');
 328 // rm {NAME}
 329 Mpc.prototype.rm                  = Mpc.__make_send_arg1('rm');
 330 // save {NAME}
 331 Mpc.prototype.save                = Mpc.__make_send_arg1('save');
 332
 333 /*
 334  * The music database
 335  * http://www.musicpd.org/doc/protocol/ch03s06.html
 336  */
 337
 338 /*
 339  * Connection settings
 340  * http://www.musicpd.org/doc/protocol/ch03s08.html
 341  */
 342
 343 // close
 344 Mpc.prototype.close               = Mpc.__make_send_void('close');
 345 // kill
 346 Mpc.prototype.kill                = Mpc.__make_send_void('kill');
 347 // password {PASSWORD}
 348 Mpc.prototype.password            = Mpc.__make_send_arg1('password');
 349 // ping
 350 Mpc.prototype.ping                = Mpc.__make_send_void('ping');
 351
 352 /*
 353  * Audio output devices
 354  * http://www.musicpd.org/doc/protocol/ch03s09.html
 355  */
 356
 357 // disableoutput {ID}
 358 Mpc.prototype.disableoutput       = Mpc.__make_send_arg1('disableoutput');
 359 // enableoutput {ID}
 360 Mpc.prototype.enableoutput        = Mpc.__make_send_arg1('enableoutput');
 361 // outputs
 362 Mpc.prototype.outputs             = Mpc.__make_send_void('outputs');
 363
 364 /*
 365  * Reflection
 366  * http://www.musicpd.org/doc/protocol/ch03s10.html
 367  */
 368
 369 // config
 370 Mpc.prototype.config              = Mpc.__make_send_void('config');
 371 // commands
 372 Mpc.prototype.commands            = Mpc.__make_send_void('commands');
 373 // notcommands
 374 Mpc.prototype.notcommands         = Mpc.__make_send_void('notcommands');
 375 // tagtypes
 376 Mpc.prototype.tagtypes            = Mpc.__make_send_void('tagtypes');
 377 // urlhandlers
 378 Mpc.prototype.urlhandlers         = Mpc.__make_send_void('urlhandlers');
 379 // decoders
 380 Mpc.prototype.decoders            = Mpc.__make_send_void('decoders');
 381
 382 /*
 383  * Client to client
 384  * http://www.musicpd.org/doc/protocol/ch03s11.html
 385  */
 386
 387 // subscribe {NAME}
 388 Mpc.prototype.subscribe           = Mpc.__make_send_arg1('subscribe');
 389 // unsubscribe {NAME}
 390 Mpc.prototype.unsubscribe         = Mpc.__make_send_arg1('unsubscribe');
 391 // channels
 392 Mpc.prototype.channels            = Mpc.__make_send_void('channels');
 393 // readmessages
 394 Mpc.prototype.readmessages        = Mpc.__make_send_void('readmessages');
 395 // sendmessage {CHANNEL} {TEXT}
 396 Mpc.prototype.sendmessage         = Mpc.__make_send_arg2('sendmessage');