from django.core.management.base import BaseCommand
from django.core.management.color import no_style
from optparse import make_option
import sys
import os

try:
    set
except NameError:
    from sets import Set as set   # Python 2.3 fallback

class Command(BaseCommand):
    option_list = BaseCommand.option_list + (
        make_option('--verbosity', action='store', dest='verbosity', default='1',
            type='choice', choices=['0', '1', '2'],
            help='Verbosity level; 0=minimal output, 1=normal output, 2=all output'),
    )
    help = 'Installs the named fixture(s) in the database.'
    args = "fixture [fixture ...]"

    def handle(self, *fixture_labels, **options):
        from django.db.models import get_apps
        from django.core import serializers
        from django.db import connection, transaction
        from django.conf import settings

        self.style = no_style()

        verbosity = int(options.get('verbosity', 1))

        # Keep a count of the installed objects and fixtures
        count = [0, 0]
        models = set()

        humanize = lambda dirname: dirname and "'%s'" % dirname or 'absolute path'

        # Get a cursor (even though we don't need one yet). This has
        # the side effect of initializing the test database (if
        # it isn't already initialized).
        cursor = connection.cursor()

        # Start transaction management. All fixtures are installed in a
        # single transaction to ensure that all references are resolved.
        transaction.commit_unless_managed()
        transaction.enter_transaction_management()
        transaction.managed(True)

        app_fixtures = [os.path.join(os.path.dirname(app.__file__), 'fixtures') for app in get_apps()]
        for fixture_label in fixture_labels:
            parts = fixture_label.split('.')
            if len(parts) == 1:
                fixture_name = fixture_label
                formats = serializers.get_serializer_formats()
            else:
                fixture_name, format = '.'.join(parts[:-1]), parts[-1]
                if format in serializers.get_serializer_formats():
                    formats = [format]
                else:
                    formats = []

            if verbosity > 2:
                if formats:
                    print "Loading '%s' fixtures..." % fixture_name
                else:
                    print "Skipping fixture '%s': %s is not a known serialization format" % (fixture_name, format)

            for fixture_dir in app_fixtures + list(settings.FIXTURE_DIRS) + ['']:
                if verbosity > 1:
                    print "Checking %s for fixtures..." % humanize(fixture_dir)

                label_found = False
                for format in formats:
                    serializer = serializers.get_serializer(format)
                    if verbosity > 1:
                        print "Trying %s for %s fixture '%s'..." % \
                            (humanize(fixture_dir), format, fixture_name)
                    try:
                        full_path = os.path.join(fixture_dir, '.'.join([fixture_name, format]))
                        fixture = open(full_path, 'r')
                        if label_found:
                            fixture.close()
                            print self.style.ERROR("Multiple fixtures named '%s' in %s. Aborting." %
                                (fixture_name, humanize(fixture_dir)))
                            transaction.rollback()
                            transaction.leave_transaction_management()
                            return
                        else:
                            count[1] += 1
                            if verbosity > 0:
                                print "Installing %s fixture '%s' from %s." % \
                                    (format, fixture_name, humanize(fixture_dir))
                            try:
                                objects = serializers.deserialize(format, fixture)
                                for obj in objects:
                                    count[0] += 1
                                    models.add(obj.object.__class__)
                                    obj.save()
                                label_found = True
                            except Exception, e:
                                fixture.close()
                                sys.stderr.write(
                                    self.style.ERROR("Problem installing fixture '%s': %s\n" %
                                         (full_path, str(e))))
                                transaction.rollback()
                                transaction.leave_transaction_management()
                                return
                            fixture.close()
                    except:
                        if verbosity > 2:
                            print "No %s fixture '%s' in %s." % \
                                (format, fixture_name, humanize(fixture_dir))

        if count[0] > 0:
            sequence_sql = connection.ops.sequence_reset_sql(self.style, models)
            if sequence_sql:
                if verbosity > 1:
                    print "Resetting sequences"
                for line in sequence_sql:
                    cursor.execute(line)

        transaction.commit()
        transaction.leave_transaction_management()

        if count[0] == 0:
            if verbosity > 2:
                print "No fixtures found."
        else:
            if verbosity > 0:
                print "Installed %d object(s) from %d fixture(s)" % tuple(count)