preprocess

#!/usr/bin/env python

from __future__ import print_function

from ast import literal_eval
from optparse import OptionParser
import os
import sys
import re
import meta

from mako.exceptions import text_error_template
from mako.lookup import TemplateLookup
from mako.template import Template



if __name__ == '__main__':

	parser = OptionParser("usage: %prog [FILENAME]")
	parser.add_option('-D', action='append', dest='defs')
	
	opts, args = parser.parse_args(sys.argv[1:])
	
	defs = {}
	for x in opts.defs or []:
		k, v = (x.split('=', 1) + ['True'])[:2]
		try:
			v = literal_eval(v)
		except (ValueError, SyntaxError):
			pass
		defs[k] = v
	
	if len(args) not in (0, 1):
		parser.error("wrong number of arguments") # Will exit

	if (len(args) == 0) or (args[0] == "-"):
		fo = sys.stdin
	else:
		filename = args[0]
		if not os.path.isfile(filename):
			raise SystemExit("error: can't find %s" % filename)
		fo = open(filename)
	
	context = meta.__dict__.copy()
	context.update(defs)
	
	data = fo.read()
	try:
		lookup = TemplateLookup(["."])
		print(Template(data, lookup=lookup).render(**context))
	except:
		sys.stderr.write(text_error_template().render())
		exit(1)