mpd.lua

   1 #!/usr/bin/lua
   2
   3 local hasuci,uci = pcall(require,"uci")
   4
   5 require("socket")
   6 json=require("json")
   7
   8 function url_decode(str)
   9   if not str then return nil end
  10   str = string.gsub (str, "+", " ")
  11   str = string.gsub (str, "%%(%x%x)", function(h) return
  12     string.char(tonumber(h,16)) end)
  13   str = string.gsub (str, "\r\n", "\n")
  14   return str
  15 end
  16
  17 function url_encode(str)
  18
  19   --Ensure all newlines are in CRLF form
  20   str = string.gsub (str, "\r?\n", "\r\n")
  21
  22   --Percent-encode all non-unreserved characters
  23   --as per RFC 3986, Section 2.3
  24   --(except for space, which gets plus-encoded)
  25   str = string.gsub (str, "([^%w%-%.%_%~:/])",
  26     function (c) return string.format ("%%%02X", string.byte(c)) end)
  27
  28   --Convert spaces to plus signs
  29   str = string.gsub (str, " ", "+")
  30
  31   return str
  32 end
  33
  34 function split(s, delimiter)
  35     local result = {};
  36     for match in (s..delimiter):gmatch("(.-)"..delimiter) do
  37         result[#result+1] = match;
  38     end
  39     return result;
  40 end
  41
  42 function string.starts(String,Start)
  43    return string.sub(String,1,string.len(Start))==Start
  44 end
  45
  46 function filename(path)
  47   local path_elems=split(path,'/')
  48   return path_elems[#path_elems]
  49 end
  50
  51 function process_playlist(playlist)
  52   local res={}
  53   local rec={}
  54   for _,record in pairs(playlist) do
  55     if record=="OK" then
  56       break
  57     end
  58     local splitted = split(record,": ")
  59     local fieldname = string.lower(splitted[1])
  60     local fieldvalue = splitted[2]
  61     rec[fieldname] = fieldvalue
  62     if fieldname=="id" then
  63       local title = rec['title']
  64       if title then
  65         local filtered_title=string.gsub(string.lower(title),'track','')
  66         local filtered_title=string.gsub(filtered_title,'[ _.-]','')
  67       else
  68         filtered_title=""
  69       end
  70       if not filtered_title or string.len(filtered_title)<4 then
  71         if title then
  72           rec['title']=title..' - '..filename(rec['file'])
  73         else
  74           rec['title']=filename(rec['file'])
  75         end
  76       end
  77       res[#res+1] = rec
  78       rec={}
  79     end
  80   end
  81   return res
  82 end
  83
  84 function find_by_id(playlist,id)
  85   for key,record in pairs(playlist) do
  86     if record['id']==id then
  87       return key
  88     end
  89   end
  90   return nil
  91 end
  92
  93 function process_playlists(playlists)
  94   local res={}
  95   for _,record in pairs(playlists) do
  96     local splitted = split(record,": ")
  97     if splitted[1]=="playlist" then
  98       res[#res+1] = splitted[2]
  99     end
 100   end
 101   return res
 102 end
 103
 104 function process_directory(directory)
 105   local res={}
 106   for _,record in pairs(directory) do
 107     local splitted = split(record,": ")
 108     if splitted[1]=="directory" or splitted[1]=="file" then
 109       local rec={}
 110       rec["type"] = splitted[1]
 111       rec["name"] = splitted[2]
 112       res[#res+1] = rec
 113     end
 114   end
 115   return res
 116 end
 117
 118 function mpd_new(settings)
 119     local client = {}
 120
 121     if settings == nil then settings = {} end
 122
 123     client.hostname = settings.hostname or "localhost"
 124     client.port     = settings.port or 6600
 125     client.desc     = settings.desc or client.hostname
 126     client.password = settings.password
 127     client.timeout  = settings.timeout or 1
 128     client.retry    = settings.retry or 60
 129
 130     return client
 131 end
 132
 133 function mpd_send(mpd,action,raw)
 134
 135     local command = string.format("%s\n", action)
 136     local values = {}
 137
 138     -- connect to MPD server if not already done.
 139     if not mpd.connected then
 140         local now = os.time();
 141         if not mpd.last_try or (now - mpd.last_try) > mpd.retry then
 142             mpd.socket = socket.tcp()
 143             mpd.socket:settimeout(mpd.timeout, 't')
 144             mpd.last_try = os.time()
 145             mpd.connected = mpd.socket:connect(mpd.hostname, mpd.port)
 146             if not mpd.connected then
 147                 return { errormsg = "could not connect" }
 148             end
 149             mpd.last_error = nil
 150
 151             -- Read the server's hello message
 152             local line = mpd.socket:receive("*l")
 153             if not line:match("^OK MPD") then -- Invalid hello message?
 154                 mpd.connected = false
 155                 return { errormsg = string.format("invalid hello message: %s", line) }
 156             else
 157                 _, _, mpd.version = string.find(line, "^OK MPD ([0-9.]+)")
 158             end
 159
 160             -- send the password if needed
 161             if mpd.password then
 162                 local rsp = mpd_send(mpd,string.format("password %s", mpd.password))
 163                 if rsp.errormsg then
 164                     return rsp
 165                 end
 166             end
 167         else
 168             local retry_sec = mpd.retry - (now - mpd.last_try)
 169             return { errormsg = string.format("%s (retrying in %d sec)", mpd.last_error, retry_sec) }
 170         end
 171     end
 172
 173     mpd.socket:send(command)
 174
 175     local line = ""; err=0
 176     while not line:match("^OK$") do
 177         line, err = mpd.socket:receive("*l")
 178         if not line then -- closed,timeout (mpd killed?)
 179             mpd.last_error = err
 180             mpd.connected = false
 181             mpd.socket:close()
 182             return mpd_send(mpd,action)
 183         end
 184
 185         if line:match("^ACK") then
 186             return { errormsg = line }
 187         end
 188
 189         if not raw then
 190
 191           local pattern = string.format("(%s)", ": ")
 192           local i = string.find (line, pattern, 0)
 193
 194           if i ~= nil then
 195               local key=string.sub(line,1,i-1)
 196               local value=string.sub(line,i+2,-1)
 197               values[string.lower(key)] = value
 198           end
 199
 200         else
 201
 202           values[#values+1]=line
 203
 204         end
 205     end
 206
 207     return values
 208 end
 209
 210 if hasuci then
 211
 212   x = uci.cursor()
 213
 214   settings = {}
 215   settings['host'] = x.get("mpd","server","host") or "localhost"
 216   settings['port'] = x.get("mpd","server","port") or 6600
 217   settings['timeout'] = x.get("mpd","server","timeout") or 1
 218
 219   volstep = x.get("mpd","control","volume_step") or 3
 220
 221   password = x.get("mpd","server","password")
 222
 223 else
 224
 225   config="/etc/mpd-lua.json"
 226
 227   settings={}
 228   local open = io.open
 229   file = open(config, "r")
 230   if file then
 231     content = file:read "*a"
 232     file:close()
 233     settings=json.decode(content)
 234   end
 235
 236   settings['host'] = settings['host'] or "localhost"
 237   settings['port'] = settings["port"] or 6600
 238   settings['timeout'] = settings["timeout"] or 1
 239
 240   volstep = settings["volstep"] or 3
 241
 242 end
 243
 244 if password then
 245   settings["password"] = password
 246 end
 247
 248 m = mpd_new(settings)
 249
 250 command = url_decode(os.getenv('QUERY_STRING'))
 251
 252 if not command or command=="" then
 253   command="idle"
 254 end
 255
 256 if command=="play" or command=="pause" or command=="stop" then
 257
 258   res=mpd_send(m,command)
 259
 260 elseif command=="previous" or command=="next" then
 261
 262   res=mpd_send(m,"play")
 263   res=mpd_send(m,command)
 264
 265 elseif command=="idle" then
 266
 267   m.timeout=30
 268   res=mpd_send(m,command)
 269
 270 elseif command=="vold" then
 271
 272   status=mpd_send(m,"status")
 273   volume=tonumber(status["volume"])
 274   res=mpd_send(m,"setvol "..(volume-volstep))
 275
 276 elseif command=="volu" then
 277
 278   status=mpd_send(m,"status")
 279   volume=tonumber(status["volume"])
 280   res=mpd_send(m,"setvol "..(volume+volstep))
 281
 282 elseif string.starts(command,"fastfwd") then
 283
 284   cmd=split(command,"|")
 285   skip=tonumber(cmd[2])
 286   if not skip then
 287     skip=15
 288   end
 289
 290   status=mpd_send(m,"status")
 291   rec_time=status["time"]
 292   song=status["songid"]
 293
 294   if song then
 295
 296     if rec_time then
 297       rec_time=split(rec_time,":")
 298       cur_time=tonumber(rec_time[1])
 299
 300       track_time=tonumber(rec_time[2])
 301       if track_time then
 302         cur_time=cur_time+skip
 303         if cur_time>track_time then
 304           cur_time=track_time
 305         end
 306       end
 307       mpd_send(m,"seekid "..song.." "..cur_time)
 308
 309     else
 310
 311       mpd_send(m,"play")
 312
 313     end
 314
 315   end
 316
 317   res={}
 318
 319 elseif string.starts(command,"rewind") then
 320
 321   cmd=split(command,"|")
 322   skip=tonumber(cmd[2])
 323   if not skip then
 324     skip=15
 325   end
 326
 327   status=mpd_send(m,"status")
 328   rec_time=status["time"]
 329   song=status["songid"]
 330
 331   if song then
 332
 333     if rec_time then
 334       rec_time=split(rec_time,":")
 335       cur_time=tonumber(rec_time[1])
 336       cur_time=cur_time-skip
 337       if cur_time<0 then
 338         cur_time=0
 339       end
 340
 341       print(song)
 342       print(cur_time)
 343       mpd_send(m,"seekid "..song.." "..cur_time)
 344
 345     else
 346
 347       mpd_send(m,"play")
 348       mpd_send(m,"previous")
 349
 350     end
 351
 352   end
 353
 354   res={}
 355
 356 elseif command=="status" then
 357
 358   res=mpd_send(m,"status")
 359   song=tonumber(res["songid"])
 360   if song then
 361     playlist=mpd_send(m,"playlistid "..song,1)
 362     pl=process_playlist(playlist)
 363     res['current_playing']=pl[1]['title']
 364   else
 365     res['current_playing']="---"
 366   end
 367
 368 elseif command=="playlist" then
 369
 370   playlist=mpd_send(m,"playlistinfo",1)
 371   res=process_playlist(playlist)
 372
 373 elseif command=="repeat" then
 374
 375   status=mpd_send(m,"status")
 376   rep=1-status["repeat"]
 377   res=mpd_send(m,"repeat "..rep)
 378
 379 elseif string.starts(command,"cpl") then
 380
 381   cmd=split(command,"|")
 382   id=cmd[3]
 383   command=cmd[2]
 384
 385   if command=="playitem" then
 386     command="playid "..id
 387     res=mpd_send(m,command)
 388   end
 389
 390   if command=="clear" then
 391     res=mpd_send(m,"clear")
 392   end
 393
 394   if command=="remove" then
 395     command="deleteid "..id
 396     res=mpd_send(m,command)
 397   end
 398
 399   if command=="moveup" then
 400     playlist=mpd_send(m,"playlistinfo ",1)
 401     pl=process_playlist(playlist)
 402     idx=find_by_id(pl,id)
 403     if idx>1 then
 404       command="swap "..(idx-1).." "..(idx-2)
 405     end
 406     res=mpd_send(m,command)
 407   end
 408
 409   if command=="movedown" then
 410     playlist=mpd_send(m,"playlistinfo ",1)
 411     pl=process_playlist(playlist)
 412     idx=find_by_id(pl,id)
 413     if idx<#pl then
 414       command="swap "..(idx-1).." "..(idx)
 415     end
 416     res=mpd_send(m,command)
 417   end
 418
 419 elseif string.starts(command,"lists") then
 420
 421   cmd=split(command,"|")
 422   command=cmd[2]
 423
 424   if command=="load" then
 425     if not cmd[3] then
 426       lists=mpd_send(m,"listplaylists",1)
 427       res=process_playlists(lists)
 428     else
 429       res=mpd_send(m,"load \""..cmd[3].."\"",1)
 430     end
 431   end
 432
 433   if command=="save" and cmd[3] then
 434     res=mpd_send(m,"save \""..cmd[3].."\"",1)
 435   end
 436
 437   if command=="delete" and cmd[3] then
 438     res=mpd_send(m,"rm \""..cmd[3].."\"",1)
 439   end
 440
 441   if command=="edit" then
 442     if cmd[3] then
 443       dir=mpd_send(m,"lsinfo \""..cmd[3].."\"",1)
 444     else
 445       dir=mpd_send(m,"lsinfo",1)
 446     end
 447     res=process_directory(dir)
 448   end
 449
 450   if command=="add" then
 451     res={}
 452     if cmd[3] then
 453       res=mpd_send(m,"add \""..cmd[3].."\"")
 454       if (res['errormsg']) then
 455         path=url_encode(cmd[3])
 456         res=mpd_send(m,"add \""..path.."\"")
 457       end
 458     end
 459   end
 460
 461 end
 462
 463 if not res then
 464   print("Content-Type: text/plain\r\n")
 465   print("MPD server - unknown command "..command)
 466 elseif (res['errormsg']) then
 467   print("Content-Type: text/plain\r\n")
 468   print("MPD server connection error: "..res['errormsg'])
 469 else
 470   print "Content-Type: text/plain\r\n"
 471   print(json.encode(res))
 472 end