#!/usr/bin/env python

import subprocess
import sys
import os
import getopt
import string

runtime_set = False

def main(argv):
	depfile_set = False
	deps_set = False
	global runtime_set
	try:
		opts, args = getopt.getopt(argv, "hrf:d:", ["help", "runtime", "file=", "deps="])
	except getopt.GetoptError:
		usage()
		sys.exit(2)
	for opt, arg in opts:
		if opt in ("-h", "--help"):
			usage()
			sys.exit(0)
		elif opt in ("-r", "--runtime"):
			runtime_set = True
		elif opt in ("-f", "--file"):
			depfile = arg
			depfile_set = True
		elif opt in ("-d", "--deps"):
			deps_arg = arg
			deps_set = True
	if (depfile_set is True) and (deps_set is True):
		usage()
		sys.exit('ERROR: You can only specify either a .dep file with the -f switch or dependencies using the -d switch.')
	elif depfile_set is True:
		deps_in = deps_from_file(depfile)
	elif deps_set is True:
		deps_in = deps_from_arg(deps_arg)
	else:
		usage()
		sys.exit(2)
	print depmin(deps_in)

def usage():
	print 'USAGE:', os.path.basename(sys.argv[0]), '[OPTIONS]'
	print 'Minimize dependencies from a .dep files, or directly from the command line.'
	print
	print 'OPTIONS:'
	print '    -f, --file       specify a .dep file'
	print '    -d, --deps       provide the dependencies in the command line. Dependencies must be wrapped in quotes.'
	print '    -r, --runtime    prefer runtime dependencies to build dependencies'
	print '    -h, --help       show this help message'
	print '  You have to use either the -f or the -d switch.'
	print
	print 'EXAMPLES:'
	print '    depmin -f wesnoth-1.8.5-i486-1gv.dep'
	print '    depmin -d "libX11,libXau,libXdmcp,libXext,libXrandr,libXrender,libxcb,sdl,svgalib,zlib"'

def strip_deps(deps):
	global runtime_set
	deps_out = []
	for i in deps:
		if i != '':
			if '|' in i:
				i = i.lstrip(' ').rstrip(' ')
				if i != '|':
					multideps = list(i.partition('|'))
					for n in xrange(len(multideps)):
						multideps[n] = multideps[n].lstrip(' ').rstrip(' ')
					if 'openssl' in multideps:
						if runtime_set:
							thedep = 'openssl-solibs'
						else:
							thedep = 'openssl'
					elif 'gcc-g++' in multideps:
						if runtime_set:
							thedep = 'cxxlibs'
						else:
							thedep = 'gcc-g++'
					elif 'glibc' in multideps:
						thedep = 'glibc'
					elif 'seamonkey' in multideps:
						if runtime_set:
							thedep = 'seamonkey-solibs'
						else:
							thedep = 'seamonkey'
					else:
						thedep = i.partition('|')[0]
					deps_out.append(thedep)
			else:
				deps_out.append(i)
	return deps_out

def deps_from_file(path):
	if not path.endswith('.dep'):
		sys.exit(path+' is not a dep file.')
	deps = []
	f = open(path)
	contents = f.readlines()
	f.close()
	for line in contents:
		depline = line.replace('\n', ' ').lstrip(' ').rstrip(' ').split(',')
		for i in depline:
			deps.append(i)
	deps = strip_deps(deps)
	return deps

def deps_from_arg(arg):
	deps = []
	depline = arg.replace('\n', ' ').lstrip(' ').rstrip(' ').split(',')
	for i in depline:
		deps.append(i)
	deps = strip_deps(deps)
	return deps
	

def pkgdeps(pkgname):
	cmd = ['/usr/sbin/slapt-get', '--show', pkgname]
	process = subprocess.Popen(cmd, env={'LANG': 'C'}, stdout=subprocess.PIPE)
	output = process.communicate()[0]
	deps = []
	for line in output.split('\n'):
		if line.startswith('Package Required'):
			deps = line.rpartition('Package Required:')[2].lstrip(' ').rstrip(' ').replace(' ', ',').split(',')
			deps = strip_deps(deps)
	return deps

def depmin(deps):
	deps_in = strip_deps(deps)
	pkgs_list = []
	deps_list = []
	for pkg in deps_in:
		deps = pkgdeps(pkg)
		pkgs_list.append(pkg)
		deps_list.append(deps)
	length = len(pkgs_list)
	deps_out = []
	for i in pkgs_list:
		match = False
		for j in range(0, length):
			if i in deps_list[j]:
				match = True
		if match is False:
			deps_out.append(i)
	out = ""
	for i in sorted(deps_out):
		out = out+i+','
	return out.rstrip(',')

if __name__ == "__main__":
	main(sys.argv[1:])