SoundManager

Copyright (c) 2011, Bart van Strien and Tommy Brunn
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soundmanager = {}
soundmanager.queue = {}
soundmanager.playlist = {}
soundmanager.currentsong = -1

local function shuffle(a, b)
   return math.random(1, 2) == 1
end

--do the magic
function soundmanager:play(sndData)
   --make a source out of the sound data
   local src = love.audio.newSource(sndData, "static")
   --put it in the queue
   table.insert(self.queue, src)
   --and play it
   love.audio.play(src)
end

--do the music magic
function soundmanager:playMusic(first, ...)
   --stop all currently playing music
   for i, v in ipairs(self.playlist) do
      love.audio.stop(v)
   end
   --decide if we were passed a table or a vararg,
   --and assemble the playlist
   if type(first) == "table" then
      self.playlist = first
   else
      self.playlist = {first, ...}
   end
   self.currentsong = 1
   --play
   love.audio.play(self.playlist[1])
end

--do some shufflin'
function soundmanager:shuffle(first, ...)
   local playlist
   if type(first) == "table" then
      playlist = first
   else
      playlist = {first, ...}
   end
   table.sort(playlist, shuffle)
   return unpack(playlist)
end

--update
function soundmanager:update(dt)
   --check which sounds in the queue have finished, and remove them
   local removelist = {}
   for i, v in ipairs(self.queue) do
      if v:isStopped() then
         table.insert(removelist, i)
      end
   end
   --we can't remove them in the loop, so use another loop
   for i, v in ipairs(removelist) do
      table.remove(self.queue, v-i+1)
   end
   --advance the playlist if necessary
   if self.currentsong ~= -1 and self.playlist and self.playlist[self.currentsong]:isStopped() then
      self.currentsong = self.currentsong + 1
      if self.currentsong > #self.playlist then
         self.currentsong = 1
      end
      love.audio.play(self.playlist[self.currentsong])
   end
end