#!/usr/bin/python
from PIL import Image
import sys
import os
import struct
from getopt import gnu_getopt

"""Convert image to raw binary using Python Imaging Library."""

def split_seq(seq, splitsize):
  newseq = []
  while seq:
    newseq.append(seq[:splitsize])
    seq = seq[splitsize:]
  return newseq

def write_block(f, image, width=8, height=8, offset_x=0, offset_y=0):
  for y in range(height):
    for x in range(width):
      val = image.getpixel((x+offset_x, y+offset_y)) 
      f.write(chr(val))
  
if __name__=="__main__":

  tiled, args = gnu_getopt(sys.argv[1:], "t")
  
  if len(args) < 2:
    print "Usage: %s [-t] <source> <target> [palette]" % os.path.split(sys.argv[0])[1]
    print "       -t   - Convert data in 8x8 pixel tiles in 1D layout."
    sys.exit()

  im = Image.open(args[0])
  output = open(args[1], "wb")
  width, height = im.size
  print "Converting %dx%d image to binary." % (width, height)
  if not tiled:
    write_block(output, im, width, height)
  else:
    print "Doing 1D tile conversion."
    if (width % 8) or (height % 8):
      print "Can't tile image where width or height is not multiple of 8."
      exit(-1)
    else:
      for offset_y in map(lambda n : 8*n, range(height / 8)):
        for offset_x in map(lambda n : 8*n, range(width / 8)):
          write_block(output, im, offset_x=offset_x, offset_y=offset_y)

  if len(args) > 2:
    pal_output = open(args[2], "wb")
    print "Converting %d color palette." % (len(im.palette.palette) / 3)
    for color in split_seq(im.palette.palette, 3):
      r, g, b = map(lambda col : col >> 3, map(ord, color))

      value = (b << 10) + (g << 5) + r
      pal_output.write(struct.pack("<h", value))