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(lvl, msg, obj) {
  12         if (this._debug_enabled & lvl)
  13                 console.log('mpc: ' + msg, obj);
  14 }
  15
  16 Mpc.prototype.err = function(msg, obj) {
  17         console.error('mpc: ' + msg, obj);
  18 }
  19
  20 Mpc.prototype.set_debug = function(val) {
  21         this._debug_enabled = val;
  22 }
  23
  24 Mpc.prototype.send = function(msg) {
  25         var _this = this;
  26         this._queue.push(msg);
  27         this._socket.send(msg, function(x) {
  28                 _this.log(0x1, 'send: ' + msg + ':', x);
  29         });
  30 }
  31
  32 Mpc.prototype.recv_msg = function(lines) {
  33         curr = this._queue.shift();
  34         this.log(0x2, 'recv: [' + curr + ']:', lines.join('\n'));
  35         curr = curr.split(' ');
  36
  37         switch (curr[0]) {
  38         // Needs to return a list of dicts (see above for dicts).
  39         //case 'playlistinfo':
  40         case 'currentsong':
  41         case 'stats':
  42         case 'status':
  43                 state = {};
  44                 keys = [];
  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                 // When mpd is stopped, it gives us back crap values for some things.
  56                 if ('state' in state && state.state == 'stop') {
  57                         if ('volume' in state && state.volume == '-1')
  58                                 keys.splice(keys.indexOf('volume'), 1);
  59                 }
  60                 // Now merge the current state with the previous one so that we don't
  61                 // lose information like volume or song position.
  62                 curr_state = this.state;
  63                 keys.forEach(function(key) {
  64                         curr_state[key] = state[key];
  65                 });
  66
  67                 this._cb_update_state(curr_state);
  68                 break;
  69         default:
  70                 this._cb_update_state(lines, curr);
  71                 break;
  72         }
  73 }
  74
  75 Mpc.prototype.recv = function(msg) {
  76         /* We can get back a bunch of responses in a row, so parse them out */
  77         /* XXX: Do we have to handle partial reads ?  like long playlists ... */
  78         lines = msg.split('\n');
  79         var i = 0;
  80         while (i < lines.length) {
  81                 if (lines[i] == 'OK' || lines[i].substr(0, 3) == 'OK ') {
  82                         this.recv_msg(lines.splice(0, i + 1));
  83                         i = 0;
  84                 } else
  85                         ++i;
  86         }
  87 }
  88
  89 /*
  90  * Command generator helpers.
  91  */
  92
  93 Mpc.__make_send_void = function(cmd) {
  94         return function() { this.send(cmd); }
  95 }
  96
  97 Mpc.__make_send_arg1 = function(cmd) {
  98         return function(a1) {
  99                 if (a1 === undefined)
 100                         this.err(cmd + ': function requires one argument');
 101                 else
 102                         this.send(cmd + ' ' + a1);
 103         }
 104 }
 105
 106 Mpc.__make_send_arg2 = function(cmd) {
 107         return function(a1, a2) {
 108                 if (a1 === undefined || a2 === undefined)
 109                         this.err(cmd + ': function requires two arguments');
 110                 else
 111                         this.send(cmd + ' ' + a1 + ' ' + a2);
 112         }
 113 }
 114
 115 Mpc.__make_send_opt = function(cmd) {
 116         return function(arg) {
 117                 if (arg === undefined)
 118                         arg = '';
 119                 this.send(cmd + ' ' + arg);
 120         };
 121 }
 122
 123 Mpc.__make_send_range = function(cmd, min, max, def) {
 124         return function(arg) {
 125                 if (arg === undefined)
 126                         arg = def;
 127                 if (arg >= min && arg <= max)
 128                         this.send(cmd + ' ' + arg);
 129                 else
 130                         this.err(cmd + ': arg must be [' + min + ',' + max + '] but got "' + arg + '"');
 131         };
 132 }
 133
 134 /*
 135  * Querying MPD's status
 136  * http://www.musicpd.org/doc/protocol/ch03.html#idp118752
 137  */
 138
 139 // clearerror
 140 Mpc.prototype.clearerror          = Mpc.__make_send_void('clearerror');
 141 // currentsong
 142 Mpc.prototype.currentsong         = Mpc.__make_send_void('currentsong');
 143 // idle [SUBSYSTEMS...]
 144 // TODO
 145 // status
 146 Mpc.prototype.status              = Mpc.__make_send_void('status');
 147 // stats
 148 Mpc.prototype.stats               = Mpc.__make_send_void('stats');
 149
 150 /*
 151  * Playback options
 152  * http://www.musicpd.org/doc/protocol/ch03s02.html
 153  */
 154
 155 // consume {STATE}
 156 Mpc.prototype.consume             = Mpc.__make_send_range('consume', 0, 1, 1);
 157 // crossfade {SECONDS}
 158 Mpc.prototype.crossfade           = Mpc.__make_send_arg1('crossfade');
 159 // mixrampdb {deciBels}
 160 Mpc.prototype.mixrampdb           = Mpc.__make_send_arg1('mixrampdb');
 161 // mixrampdelay {SECONDS|nan}
 162 // Note: Probably should handle javascript NaN here.
 163 Mpc.prototype.mixrampdelay        = Mpc.__make_send_arg1('mixrampdelay');
 164 // random {STATE}
 165 Mpc.prototype.random              = Mpc.__make_send_range('random', 0, 1, 1);
 166 // repeat {STATE}
 167 Mpc.prototype.repeat              = Mpc.__make_send_range('repeat', 0, 1, 1);
 168 // setvol {VOL}
 169 Mpc.prototype.setvol              = Mpc.__make_send_range('setvol', 0, 100);
 170 // single {STATE}
 171 Mpc.prototype.single              = Mpc.__make_send_range('single', 0, 1, 1);
 172 // replay_gain_mode {MODE}
 173 Mpc.prototype.replay_gain_mode    = Mpc.__make_send_arg1('replay_gain_mode');
 174 // replay_gain_status
 175
 176 /*
 177  * Controlling playback
 178  * http://www.musicpd.org/doc/protocol/ch03s03.html
 179  */
 180
 181 // next
 182 Mpc.prototype.next                = Mpc.__make_send_void('next');
 183 // pause {PAUSE}
 184 Mpc.prototype.pause               = Mpc.__make_send_range('pause', 0, 1, 1);
 185 // play [SONGPOS]
 186 Mpc.prototype.play                = Mpc.__make_send_opt('play');
 187 // playid [SONGID]
 188 Mpc.prototype.playid              = Mpc.__make_send_opt('playid');
 189 // previous
 190 Mpc.prototype.previous            = Mpc.__make_send_void('previous');
 191 // seek {SONGPOS} {TIME}
 192 Mpc.prototype.seek                = Mpc.__make_send_arg2('seek');
 193 // seekid {SONGID} {TIME}
 194 Mpc.prototype.seekid              = Mpc.__make_send_arg2('seekid');
 195 // seekcur {TIME}
 196 Mpc.prototype.seekcur             = Mpc.__make_send_arg1('seek');
 197 // stop
 198 Mpc.prototype.stop                = Mpc.__make_send_void('stop');
 199
 200 /*
 201  * Connection settings
 202  * http://www.musicpd.org/doc/protocol/ch03s08.html
 203  */
 204
 205 // close
 206 Mpc.prototype.close               = Mpc.__make_send_void('close');
 207 // kill
 208 Mpc.prototype.kill                = Mpc.__make_send_void('kill');
 209 // password {PASSWORD}
 210 Mpc.prototype.password            = Mpc.__make_send_arg1('password');
 211 // ping
 212 Mpc.prototype.ping                = Mpc.__make_send_void('ping');
 213
 214 /*
 215  * Audio output devices
 216  * http://www.musicpd.org/doc/protocol/ch03s09.html
 217  */
 218
 219 // disableoutput {ID}
 220 Mpc.prototype.disableoutput       = Mpc.__make_send_arg1('disableoutput');
 221 // enableoutput {ID}
 222 Mpc.prototype.enableoutput        = Mpc.__make_send_arg1('enableoutput');
 223 // outputs
 224 Mpc.prototype.outputs             = Mpc.__make_send_void('outputs');
 225
 226 /*
 227  * Reflection
 228  * http://www.musicpd.org/doc/protocol/ch03s10.html
 229  */
 230
 231 // config
 232 Mpc.prototype.config              = Mpc.__make_send_void('config');
 233 // commands
 234 Mpc.prototype.commands            = Mpc.__make_send_void('commands');
 235 // notcommands
 236 Mpc.prototype.notcommands         = Mpc.__make_send_void('notcommands');
 237 // tagtypes
 238 Mpc.prototype.tagtypes            = Mpc.__make_send_void('tagtypes');
 239 // urlhandlers
 240 Mpc.prototype.urlhandlers         = Mpc.__make_send_void('urlhandlers');
 241 // decoders
 242 Mpc.prototype.decoders            = Mpc.__make_send_void('decoders');
 243
 244 /*
 245  * Client to client
 246  * http://www.musicpd.org/doc/protocol/ch03s11.html
 247  */
 248
 249 // subscribe {NAME}
 250 Mpc.prototype.subscribe           = Mpc.__make_send_arg1('subscribe');
 251 // unsubscribe {NAME}
 252 Mpc.prototype.unsubscribe         = Mpc.__make_send_arg1('unsubscribe');
 253 // channels
 254 Mpc.prototype.channels            = Mpc.__make_send_void('channels');
 255 // readmessages
 256 Mpc.prototype.readmessages        = Mpc.__make_send_void('readmessages');
 257 // sendmessage {CHANNEL} {TEXT}
 258 Mpc.prototype.sendmessage         = Mpc.__make_send_arg2('sendmessage');