mpd.lua

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