#!/usr/bin/python

"""
This script tries to set ordering in which packages ought to be sent to builders.
Input: file with names of packages (without the .spec suffix). One package name per line.
Output: sorted packages on stdout.

If the script goes in a infinite loop, that means there is a cycle or other bug.
"""

import os
import re
import sys

PATTERN = re.compile('BuildRequires:\s+(.*?)(\s|$|-devel)')
DIR = '/home/users/builder/rpm/packages'

packages = {}
packages_res = {}

def build_requires(name):
	global packages
	res = []
	with open(os.path.join(DIR, name, name + '.spec'), 'r') as f:
		for line in f:
			br = PATTERN.match(line)
			if br:
				p = br.group(1)
				if p in packages:
					res.append(p)
	return res

def print_packages(p):
	global packages, packages_res

	if not packages_res[p]:
		packages_res[p] = 1
		for pp in packages[p]:
			if not packages_res[pp]:
				print_packages(pp)
		print p

if __name__ == "__main__":
	if len(sys.argv) < 2:
		print "Usage: %s filename" % sys.argv[0]
		sys.exit(1)
	with open(sys.argv[1], 'r') as f:
		for line in f:
			p = line.rstrip()
			packages[p] = []
			packages_res[p] = 0
	for p in packages.keys():
		res = build_requires(p)
		if res:
			packages[p] = res[:]

#	for p in packages.keys():
#		print p, packages[p]

	for p in packages.keys():
		print_packages(p)