require "vstruct"

print("FLAC reader")

file = "/media/sdc1/Random Downloaded/07 - spirit in the sky.flac"

print(file)

fd = io.open ( file , r )
s = fd:read ( 4 )

--fileinfo = { }

if s == "fLaC" then 
	filetyp = "flac"
	
	t = vstruct.unpack ( fd , ">b1u3" )
	lastmetadatablock = t [ 1 ]
	blocktype = t [ 2 ]
	blocklength = t [ 3 ] -- Is in bytes
	
	if blocktype == 0 then -- Stream info
		t = vstruct.unpack ( fd , ">u2u2u3u3" )
		minblocksize = t [ 1 ]
		maxblocksize = t [ 2 ]
		minframesize = t [ 3 ]
		maxframesize = t [ 4 ]
		samplerate = t [ 5 ]
		channels = t [ 6 ] + 1
		bitspersample = t [ 7 ]
		totalsamples = t [ 8 ]
		md5rawaudio = t [ 9 ]
	elseif blocktype == 1 then -- Padding
		t = vstruct.unpack ( fd , ">x" .. blocklength )
	elseif blocktype == 2 then -- Application
		t = vstruct.unpack ( fd , ">u4s" .. ( blocklength - 4 ) )
		appID = t [ 1 ]
		appdata = t [ 2 ]
	elseif blocktype == 3 then -- Seektable
		t = vstruct.unpack ( fd , ">x" .. blocklength ) -- We don't deal with seektables, skip over it
	elseif blocktype == 4 then -- Vorbis_Comment http://www.xiph.org/vorbis/doc/v-comment.html
		t = vstruct.unpack ( fd , "<u4" )
		vendor_length = t [ 1 ]
		t = vstruct.unpack ( fd , "<s" .. vendor_length .. "u4" )
		vendor_string = t [ 1 ]
		user_comment_list_length = t [ 2 ]
		
		comment = { }
		tags = { }
		for i = 1 , ( user_comment_list_length + 1 ) do
			t = vstruct.unpack ( fd , "<u4" )
			local length = t [ 1 ]
			t = vstruct.unpack ( fd , "<s" .. length )
			comment [ i ] = t [ 1 ]
			local fieldname , value = string.match ( comment [ i ] , "([^=]+)=(.+)")
			tags [ fieldname ] = tags [ fieldname ] or { }
			table.insert ( tags [ fieldname ] , value )
		end
		
	elseif blocktype == 5 then -- Cuesheet
		t = vstruct.unpack ( fd , ">s128u8x259x1x" .. ( blocklength - ( 128 + 8 + 259 + 1 ) ) ) -- cbf, TODO: cuesheet reading
	elseif blocktype == 6 then -- Picture
		t = vstruct.unpack ( fd , ">u4u4" )
		picturetype = t [ 1 ]
		mimelength = t [ 2 ]
		t = vstruct.unpack ( fd , ">s" .. mimelength .. "u4" )
		mimetype = t [ 1 ]
		descriptionlength = t [ 2 ]
		t = vstruct.unpack ( fd , ">s" .. descriptionlength .. "u4u4u4u4u4" )
		width = t [ 1 ]
		height = t [ 2 ]
		colourdepth = t [ 3 ]
		numberofcolours = t [ 4 ]
		picturelength = t [ 5 ]
		t = vstruct.unpack ( fd , ">s" .. picturelength )
		picturedata = t [ 1 ]
	end
	
	for i,v in pairs ( t ) do print (i,v) end
end
fd:close ( )