#!/usr/bin/env python
# Copyright 1999-2018 Gentoo Authors
# Distributed under the terms of the GNU General Public License v2

import os, re, signal, subprocess, sys

options=[
	'--get-hosts',
	'--set-hosts',
	'--get-verbose',
	'--set-verbose',
	'--get-log',
	'--set-log',
	'--update-masquerade',
	'--update-masquerade-with-crossdev',
	'--help',
	'--get-env',
	'--set-env'
]

tmpcmdline=sys.argv[1:]
cmdline=[]

eprefix = '@EPREFIX@'
bindir = os.path.join(eprefix, 'usr', 'bin')
sbindir = os.path.join(eprefix, 'usr', 'sbin')
libdir = os.path.join(eprefix, '@libdir@')
sysconfdir = os.path.join(eprefix, 'etc')

gcc_config = os.path.join(bindir, 'gcc-config')
env_update = os.path.join(sbindir, 'env-update')
envfile = os.path.join(sysconfdir, 'env.d', '02distcc')
default_distcc_dir = os.path.join(sysconfdir, 'distcc')
hostfile = os.path.join(default_distcc_dir, 'hosts')
distcc_path = os.path.join(bindir, 'distcc')
dccc_dir = os.path.join(libdir, 'distcc', 'bin')

def exithandler(foo,bar):
	os.kill(0,signal.SIGKILL)
	sys.exit(1)

signal.signal(signal.SIGINT,exithandler)

def isroot(ret=0):
	if os.getuid() != 0:
		if ret == 0:
			print('!!! %s %s must be run as root' % (sys.argv[:1][0],tmpcmdline[0]))
			sys.exit(1)
		else:
			retval = 0
	else:
		retval = 1
	return retval

def writeenv(var,value):
	isroot()
	distcc_env    = []
	distcc_env    = open(envfile, 'r').readlines()
	distcc_env_new = open(envfile, 'w')
	for i in range(len(distcc_env)):
		if re.compile(var+'="(.*)"').match(distcc_env[i]):
			distcc_env[i] = var+'="'+value+'"\n'
		distcc_env_new.write(distcc_env[i])
	#print('Set %s to: %s ' % (var,value))
	subprocess.Popen(env_update, shell=True)
	print('If you want to use these new settings in an existing shell,')
	print('you need to "source /etc/profile" to get the changes.')

def readenv(var):
	distcc_env = open(envfile, 'r').read()
	match = re.compile(var+'="(.*)"').search(distcc_env)
	if match:
		print(var+'='+match.group(1))
	else:
		print(var,'not set.')

def installlink(chost='', version=''):
	for file in ['gcc', 'cc', 'c++', 'g++']:
		if not chost == '':
			file = '%s-%s' % (chost,file)
		if not version == '':
			file = '%s-%s' % (file,version)
		path = os.path.join(dccc_dir,file)
		if os.path.exists(os.path.join(bindir,file)):
			if not os.path.exists(path):
				print('Creating %s symlink...' % (path))
				os.symlink(distcc_path,path)
			#else:
			#	print('Already exists. Skipping...')

def installlinks():
	p = subprocess.Popen([gcc_config+" -C -l"], shell=True, stdout=subprocess.PIPE)
	lines = p.stdout.read().decode().rstrip().split('\n')
	for line in lines:
		columns = line.split()
		if len(columns) >= 2:
			matches = re.match("(.*)-(.*)", columns[1])
			chost = matches.group(1)
			version = matches.group(2)
			installlink(chost)
			installlink(chost, version)

def uninstalllinks():
	for root, dirs, files in os.walk(dccc_dir):
		for file in files:
			os.remove(os.path.join(root, file))

def createdistccdir(dir):
	if not os.path.exists(dir):
		os.mkdir(dir)
		os.chmod(dir, 0o755)

for x in tmpcmdline:
	if not x:
		continue
	if x[0:2]=="--":
		if not x in options:
			print("!!! Error: %s is an invalid option." % (x))
			sys.exit(1)
	else:
		cmdline = x

if '--get-hosts' in tmpcmdline:
	HOSTS_ENV  = os.environ.get('DISTCC_HOSTS')
	HOSTS_HOME = os.path.join(os.environ.get('HOME'), '.distcc', 'hosts')
	if HOSTS_ENV:
		print(HOSTS_ENV)
	elif os.path.isfile(HOSTS_HOME) and os.path.getsize(HOSTS_HOME) != 0:
		print(HOSTS_HOME)
	elif os.path.exists(hostfile):
		print(open(hostfile, 'r').read().rstrip())
	else:
		print('No configuration file found. Setup your hosts with --set-hosts.')
elif '--set-hosts' in tmpcmdline:
	if isroot(1):
		PATH = default_distcc_dir
	else:
		PATH = os.path.join(os.environ.get('HOME'), '.distcc')
	createdistccdir(PATH)
	open(os.path.join(PATH, 'hosts'), 'w').write(cmdline + '\n')
elif '--get-verbose' in tmpcmdline:
	readenv('DISTCC_VERBOSE')
elif '--set-verbose' in tmpcmdline:
	writeenv('DISTCC_VERBOSE',tmpcmdline[1])
elif '--get-log' in tmpcmdline:
	readenv('DISTCC_LOG')
elif '--set-log' in tmpcmdline:
	writeenv('DISTCC_LOG',tmpcmdline[1])
elif '--update-masquerade' in tmpcmdline:
	isroot()
	uninstalllinks()
	print('Creating symlinks...')
	installlink()
	installlinks()
elif '--update-masquerade-with-crossdev' in tmpcmdline:
	isroot()
	uninstalllinks()
	print('Creating symlinks...')
	installlinks()
elif '--get-env' in tmpcmdline:
	if len(tmpcmdline) == 1:
		print(open(envfile, 'r').read().rstrip())
	elif len(tmpcmdline) == 2:
		readenv(tmpcmdline[1])
	else:
		print('!!! Error: Specify only one variable.')
elif '--set-env' in tmpcmdline:
	if len(tmpcmdline) > 2 and len(tmpcmdline) <= 3:
		isroot()
		writeenv(tmpcmdline[1],tmpcmdline[2])
	else:
		print('!!! Error: Awaiting two parameters.')
else:
	cmd = sys.argv[:1][0]
	print('Usage: %s --set-hosts DISTCC_HOSTS | --get-hosts' % (cmd))
	print('       %s --set-verbose { 0 | 1 }  | --get-verbose' % (cmd))
	print('       %s --set-log FILE           | --get-log' % (cmd))
	print('       %s --set-env VARIABLE VALUE | --get-env [VARIABLE]' % (cmd))
	print('       %s --update-masquerade' % (cmd))
	print('       %s --update-masquerade-with-crossdev' % (cmd))