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