#!/usr/bin/python3

## live-build(7) - Live System Build Components
## Copyright (C) 2006-2013 Daniel Baumann <mail@daniel-baumann.ch>
##
## This program comes with ABSOLUTELY NO WARRANTY; for details see COPYING.
## This is free software, and you are welcome to redistribute it
## under certain conditions; see COPYING for details.


import argparse
import configparser
import glob
import os
import shutil
import subprocess
import sys


# TODO:
#   * logfile output
#   * lockfile handling
#   * use gettext for i18n
#   * cdebootstrap-options from config/options/cdebootstrap
#   * take mirrors from config/archives/mirror.{bootstrap,chroot}

def main():
	## Parsing Arguments
	arguments = argparse.ArgumentParser(
		prog            = 'lb bootstrap-cdebootstrap',
		usage           = '%(prog)s [arguments]',
		description     = '''live-build contains the components to build a live system from a configuration directory.
		                     The bootstrap-cdebootstrap command bootstraps the chroot system with cdebootstrap.''',
		epilog          = 'See \'man lb-bootstrap-cdebootstrap\' for more information.',
		formatter_class = argparse.ArgumentDefaultsHelpFormatter
	)

	arguments.add_argument('--version',              help='show program\'s version number and exit', action='version', version='live-build 4')
	arguments.add_argument('--verbose',              help='set verbose option',                      action='store_true')
	arguments.add_argument('--cdebootstrap-options', help='set cdebootstrap(1) options' )

	args = arguments.parse_args()

	## Parsing Configuration
	if not os.path.isfile('config/build'):
		print('E: config/build - no such file', file=sys.stderr)

		sys.exit(1)

	config = configparser.ConfigParser()

	config.read('config/build')

	try:
		architecture     = config.get('Image', 'Architecture')
		distribution     = config.get('Image', 'Parent-Distribution')
		mirror_bootstrap = config.get('Image', 'Parent-Mirror-Bootstrap')
	except:
		distribution     = config.get('Image', 'Distribution')
		mirror_bootstrap = config.get('Image', 'Mirror-Bootstrap')

	# --verbose
	verbose = args.verbose

	# --cdebootstrap-options
	cdebootstrap_options_late = distribution + ' chroot ' + mirror_bootstrap

	cdebootstrap_options_early = ''

	if (architecture) and (not architecture == 'auto'):
		cdebootstrap_options_early = cdebootstrap_options_early + ' --arch=' + architecture

	if args.cdebootstrap_options:
		cdebootstrap_options = cdebootstrap_options_early + ' ' + args.cdebootstrap_options + ' ' + cdebootstrap_options_late
	else:
		cdebootstrap_options = cdebootstrap_options_early + ' ' + cdebootstrap_options_late

	## Calling cdebootstrap

	# stagefile
	if os.path.isfile('.build/bootstrap'):
		if verbose:
			print('I: bootstrap already done - nothing to do')

		sys.exit(0)

	# dependencies
	if not os.path.isfile('/usr/bin/cdebootstrap'):
		print('E: /usr/bin/cdebootstrap - no such file', file=sys.stderr)

		if verbose:
			print('I: cdebootstrap can be obtained from:\n'
			      'I:   http://anonscm.debian.org/gitweb/?p=users/waldi/cdebootstrap.git\n'
			      'I:   http://ftp.debian.org/debian/pool/main/c/cdebootstrap/\n'
			      'I: On Debian based systems, cdebootstrap can be installed with:\n'
			      'I:   # sudo apt-get install cdebootstrap')

		sys.exit(1)

	# clean
	if os.path.exists('chroot'):
		print('E: chroot already exists - unclean build', file=sys.stderr)

		if verbose:
			print('I: use \'lb clean\' to clean up a previously incomplete build')

		sys.exit(1)

	# stage cache
	if os.path.exists('cache/bootstrap'):
		if verbose:
			print('I: Copying cache/bootstrap to chroot')

		# Notes:
		#  * there's no Python equivalent to 'cp -a' that handels both symlinks and device nodes properly.
		cache = subprocess.call('cp -a cache/bootstrap chroot', shell=True)

		os.makedirs('.build', exist_ok=True)
		open('.build/bootstrap', 'w').close()

		sys.exit(0)

	# packages cache
	if glob.glob('cache/packages.bootstrap/*.deb'):
		if verbose:
			print('I: Copying cache/packages.bootstrap/*.deb to chroot/var/cache/bootstrap/*.deb')

		# Notes:
		#   * copy instead of move to make cache survive incomplete build
		os.makedirs('chroot/var/cache/bootstrap', exist_ok=True)

		for package in glob.glob('cache/packages.bootstrap/*.deb'):
			os.link(package, os.path.join('chroot/var/cache/bootstrap/' + os.path.basename(package)))
	else:
		# cdebootstrap
		if verbose:
			print('I: Calling \'/usr/bin/debootstrap --download-only ' + cdebootstrap_options + '\'')

			# Notes:
			#   * calling cdebootstrap twice:
			#     - to use already downloaded /var/cache/bootstrap/*.deb on incomplete builds
			#     - to use /var/cache/boottrap/*.deb for debian-installer
			cdebootstrap = subprocess.call('/usr/bin/cdebootstrap --download-only ' + cdebootstrap_options, shell=True)

		# package cache
		if glob.glob('chroot/var/cache/bootstrap/*.deb'):
			if verbose:
				print('I: Copying chroot/var/cache/bootstrap/*.deb to cache/packages.bootstrap')

			# Notes:
			#   * remove first to keep cache minimal
			#   * remove files instead of directory to work with symlinked directory
			for package in glob.glob('cache/packages.bootstrap/*.deb'):
				os.remove(package)

			os.makedirs('cache/packages.bootstrap', exist_ok=True)

			for package in glob.glob('chroot/var/cache/bootstrap/*.deb'):
				shutil.copy2(package, 'cache/packages.bootstrap')

	# cdebootstrap
	if not os.path.exists('chroot/bin'):
		if verbose:
			print('I: Calling \'/usr/bin/debootstrap ' + cdebootstrap_options + '\'')

		cdebootstrap = subprocess.call('/usr/bin/cdebootstrap ' + cdebootstrap_options, shell=True)

	# stage cache
	if not os.path.exists('cache/bootstrap'):
		if verbose:
			print('I: Copying chroot to cache/bootstrap')

		# Notes:
		#  * there's no Python equivalent to 'cp -a' that handels both symlinks and device nodes properly.
		cache = subprocess.call('cp -a chroot cache/bootstrap', shell=True)

	# stagefile
	os.makedirs('.build', exist_ok=True)
	open('.build/bootstrap', 'w').close()


if __name__ == '__main__':
	main()