# Copyright 2010 Mike Wakerly <opensource@hoho.com>
#
# This file is part of the Pykeg package of the Kegbot project.
# For more information on Pykeg or Kegbot, see http://kegbot.org/
#
# Pykeg 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, either version 2 of the License, or
# (at your option) any later version.
#
# Pykeg 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 Pykeg.  If not, see <http://www.gnu.org/licenses/>.

import sys

from django.core.management.base import BaseCommand
from django.core.management.base import CommandError

from pykeg.core import backup
from pykeg.core import models

from optparse import make_option

class Command(BaseCommand):
    option_list = BaseCommand.option_list + (
        make_option('-s', '--site',
          type='string',
          action='store',
          dest='site',
          default='default',
          help='Site to load to/from.'),
        make_option('-d', '--dump',
          type='string',
          action='store',
          dest='dump',
          help='Filename to dump to (dump mode).'),
        make_option('-r', '--restore',
          type='string',
          action='store',
          dest='restore',
          help='Filename to restore from (restore mode).'),
        make_option('-i', '--indent',
          action='store_true',
          dest='indent',
          default=True,
          help='Indent and pretty-print the output.'),
        )

    help = """Kegbot dump/restore tool. WARNING: Experimental."""
    args = '<none>'

    def handle(self, *args, **options):
        if not options['site']:
            raise CommandError('Must give --site')

        if not (bool(options['dump']) ^ bool(options['restore'])):
            raise CommandError('Must give exactly one of: --dump=<filename>, --restore=<filename>')

        kbsite = self.prep_site(options['site'], options['restore'])

        if options['restore']:
            input_fp = open(options['restore'], 'r')
            backup.restore(input_fp, kbsite, self.debug)
            input_fp.close()
        else:
            indent = None
            if options['indent']:
                indent = 2
            output_fp = open(options['dump'], 'w')
            backup.dump(output_fp, kbsite, indent, self.debug)
            output_fp.close()

    def prep_site(self, sitename, restore):
        if restore:
            if models.KegbotSite.objects.filter(name=sitename).count():
                raise CommandError('Cannot restore: Site "%s" already exists; delete '
                    'with kb_delete_site first ' % (sitename,))
            kbsite = models.KegbotSite.objects.create(name=sitename)
        else:
            try:
                kbsite = models.KegbotSite.objects.get(name=sitename)
            except models.KegbotSite.DoesNotExist:
                raise CommandError('Cannot dump: Site "%s" does not exist' % (sitename,))

    def debug(self, msg):
        print msg
