#! /usr/bin/env waf

top = '.'
out = 'tmp_out'

import os, random, time
from waflib import ConfigSet, Context, Build, Configure, Utils

Configure.autoconfig='clobber'

def options(opt):
	opt.add_option('--based', action='store', default='foo', help='base directory', dest='based')
	opt.add_option('--dumpf', action='store', default='foo', help='dump config to this file', dest='dumpf')
	opt.add_option('--force-autoconfig', action='store', default=False, dest='force_autoconfig')

def configure(ctx):
	# force autoconfig to depend on an always-changing file - once
	if ctx.options.force_autoconfig:
		fname = ctx.options.dumpf + '_autoconfig'
		s = "%f%d" % (time.time(), random.randint(0, 10**9))
		Utils.writef(fname, s)
		ctx.files.append(fname)
		Configure.autoconfig = False

def build(ctx):
	pass

def write_conf(ctx):
	if not ctx.options.dumpf:
		raise ValueError('Missing --dumpf option')
	if not ctx.options.based:
		raise ValueError('Missing --based option')

	def g(x):
		# path from conf.options.based
		based = ctx.root.find_node(ctx.options.based)
		node = ctx.root.find_node(x)
		return node.path_from(based)

	env = ConfigSet.ConfigSet()
	env.cwd_dir = g(os.getcwd())
	env.top_dir = g(Context.top_dir)
	env.out_dir = g(Context.out_dir)
	env.run_dir = g(Context.run_dir)
	env.launch_dir = g(Context.launch_dir)

	env.store(ctx.options.dumpf)

for y in (Build.BuildContext, Configure.ConfigurationContext):
	class tmp(y):
		def execute(self, *k, **kw):
			super(self.__class__, self).execute(*k, **kw)
			write_conf(self)