#!/usr/bin/env python

__author__ = "Hans Meine <hans_meine@gmx.net>"

import fig, sys, re, os.path
from optparse import OptionParser

op = OptionParser(
	usage = "%prog <infile> <bgcolor> <opacity>",
	description=
	"""Creates a dimmed / grayed-out version of an XFig file (e.g. for use with PGF/Beamer).

The background color needs to be specified in the usual hex notation (e.g. #ffffff for white), and opacity is the opacity in percentage as specified in the colormixin-environment (e.g. 15 in the beamer themes I used).  In LaTeX, you can use \colorcurrentmixin to get the values matching the effect applied to the surrounding text.

The input filename may be '-' for stdin, and if no output filename is given, the output will be sent to stdout.""")
op.add_option("-o", "--output", action="store", dest="filename",
			  help="Output filename (default: output to stdout)")
options, args = op.parse_args()

if len(args) != 3:
	sys.stderr.write("ERROR: Wrong number or arguments.\n\n")
	op.print_help(sys.stderr)
	sys.exit(1)

filename = args[0]
if filename == "-":
	filename = sys.stdin # constructor parameter for fig.File

backgroundColor = fig.CustomColor(None, args[1])
alpha = float(args[2])/100

def blend(rgb):
	def blendChannel(fg, bg):
		return int(round(alpha*fg + (1-alpha)*bg))
	return map(blendChannel, rgb, backgroundColor)

figFile = fig.File(filename)

for c in figFile.colors:
	c.setRGB(*blend(c))

standardMapping = []
for c in fig.standardColors:
	standardMapping.append(None)
standardMapping.append(-1) # map fig.colorDefault to itself

def mapColor(c):
	if c >= fig.colorCustom0:
		return c
	result = standardMapping[c]
	if result == None:
		result = figFile.getColor(blend(fig.standardColors[c]))
		standardMapping[c] = result
	return result

for o in figFile.allObjects():
	o.penColor = mapColor(o.penColor)
	o.fillColor = mapColor(o.fillColor)

if options.filename:
	figFile.save(options.filename)
else:
	sys.stdout.write(str(figFile))