# Deb-o-Matic
#
# Copyright (C) 2007-2009 Luca Falavigna
#
# Author: Luca Falavigna <dktrkranz@debian.org>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; version 3 of the License.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.

import os
import sys
from hashlib import sha256
from time import strftime
from urllib import urlopen
from Debomatic import locks
from Debomatic import Options

def setup_pbuilder(directory, configdir, distopts):
    if not os.path.exists(os.path.join(directory)):
        os.mkdir(os.path.join(directory))
    if not locks.pbuilderlock_acquire(distopts['distribution']):
        raise RuntimeError
    try:
        needs_update(directory, distopts['mirror'], distopts['distribution'])
    except RuntimeError, result:
        try:
            prepare_pbuilder(result.args[0], directory, configdir, distopts)
        except RuntimeError, error:
            raise error
        if not os.path.exists(os.path.join(directory, 'gpg')):
            os.mkdir(os.path.join(directory, 'gpg'))
        gpgfile = os.path.join(directory, 'gpg', distopts['distribution'])
        fd = os.open(gpgfile, os.O_WRONLY | os.O_CREAT, 0664)
        try:
            remote = urlopen('%s/dists/%s/Release.gpg' % (distopts['mirror'], distopts['distribution'])).read()
        except:
            locks.pbuilderlock_release(distopts['distribution'])
            raise RuntimeError(_('Unable to fetch %(mirror)s/dists/%(dist)s/Release.gpg') % {'mirror':distopts['mirror'], 'dist':distopts['distribution']})
        os.write(fd, remote)
        os.close(fd)
    locks.pbuilderlock_release(distopts['distribution'])

def needs_update(directory, mirror, distribution):
    if not os.path.exists(os.path.join(directory, 'gpg')):
        os.mkdir(os.path.join(directory, 'gpg'))
    gpgfile = os.path.join(directory, 'gpg', distribution)
    if not os.path.exists(gpgfile):
        raise RuntimeError('create')
    try:		
        fd = os.open(gpgfile, os.O_RDONLY)
    except OSError:
        raise RuntimeError('create')
    try:
        remote = urlopen('%s/dists/%s/Release.gpg' % (mirror, distribution)).read()
    except:
        print _('Unable to fetch %(mirror)s/dists/%(dist)s/Release.gpg') % {'mirror':mirror, 'dist':distribution}
        raise RuntimeError('update')
    remote_sha = sha256()
    gpgfile_sha = sha256()
    remote_sha.update(remote)
    gpgfile_sha.update(os.read(fd, os.fstat(fd).st_size))
    os.close(fd)
    if remote_sha.digest() != gpgfile_sha.digest():
        raise RuntimeError('update')

def prepare_pbuilder(cmd, directory, configdir, distopts):
    if not os.path.exists(os.path.join(directory, 'build')):
        os.mkdir(os.path.join(directory, 'build'))
    if not os.path.exists(os.path.join(directory, 'aptcache')):
        os.mkdir(os.path.join(directory, 'aptcache'))
    if not os.path.exists(os.path.join(directory, 'logs')):
        os.mkdir(os.path.join(directory, 'logs'))
    base = '--basepath' if Options.get('default', 'builder') == 'cowbuilder' else '--basetgz'
    if (os.system('%(builder)s --%(cmd)s %(basetype)s %(directory)s/%(distribution)s \
                  --override-config --configfile %(cfg)s --buildplace %(directory)s/build \
                  --aptcache "%(directory)s/aptcache" --logfile %(directory)s/logs/%(cmd)s.%(now)s >/dev/null 2>&1' \
                  % {'builder': Options.get('default', 'builder'), 'cmd': cmd, 'directory': directory, 'basetype': base, \
                     'distribution': distopts['distribution'], 'cfg': os.path.join(configdir, distopts['distribution']), \
                     'now': strftime('%Y%m%d_%H%M')})):
        locks.pbuilderlock_release(distopts['distribution'])
        raise RuntimeError(_('%(builder)s %(cmd)s failed') % {'builder':Options.get('default', 'builder'), 'cmd':cmd})