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