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