#! /usr/bin/env python

import os, sys, imp, re
from waflib import Context, Options, Configure, Utils, Logs

def options(opt):
	opt.load('compiler_c')

def configure(conf):
	conf.options = Options.options
	conf.load('compiler_c')


re_com = re.compile("#.*$", re.M)
def build(bld):
	txt = bld.path.find_node('cbit').read()
	txt = re_com.sub('', txt)

	tg = None
	for x in txt.splitlines():
		if not x:
			continue
		elif x.startswith(('\t', ' ')):
			tg.rule = x.lstrip()
		else:
			line = x.split(':')
			tgt = line[0].lstrip()
			src = line[1].lstrip()
			tg = bld()
			if src:
				tg.source = src
			if tgt:
				tg.target = tgt

def recurse_rep(x, y):
	f = getattr(Context.g_module, x.cmd or x.fun, Utils.nada)
	return f(x)

def start(cwd, version, wafdir):
	# simple example, the file main.c is hard-coded
	try:
		os.stat(cwd + os.sep + 'cbit')
	except:
		print('call from a folder containing a file named "cbit"')
		sys.exit(1)

	Logs.init_log()
	Context.waf_dir = wafdir
	Context.top_dir = Context.run_dir = cwd
	Context.out_dir = os.path.join(cwd, 'build')
	Context.g_module = imp.new_module('wscript')
	Context.g_module.root_path = os.path.join(cwd, 'cbit')
	Context.Context.recurse = recurse_rep

	# this is a fake module, which looks like a standard wscript file
	Context.g_module.options = options
	Context.g_module.configure = configure
	Context.g_module.build = build

	Options.OptionsContext().execute()

	do_config = 'configure' in sys.argv
	try:
		os.stat(cwd + os.sep + 'build')
	except:
		do_config = True
	if do_config:
		Context.create_context('configure').execute()

	if 'clean' in sys.argv:
		Context.create_context('clean').execute()
	if 'build' in sys.argv:
		Context.create_context('build').execute()