import sys

import os

import gzip

import zipfile

from optparse import make_option

from django.core.management.base import BaseCommand

from django.core.management.color import no_style

try:

    set

except NameError:

    from sets import Set as set   # Python 2.3 fallback

try:

    import bz2

    has_bz2 = True

except ImportError:

    has_bz2 = False

class Command(BaseCommand):

    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))

        show_traceback = options.get('traceback', False)

        # commit is a stealth option - it isn't really useful as

        # a command line option, but it can be useful when invoking

        # loaddata from within another script.

        # If commit=True, loaddata will use its own transaction;

        # if commit=False, the data load SQL will become part of

        # the transaction in place when loaddata was invoked.

        commit = options.get('commit', True)

        # Keep a count of the installed objects and fixtures

        fixture_count = 0

        object_count = 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.

        if commit:

            transaction.commit_unless_managed()

            transaction.enter_transaction_management()

            transaction.managed(True)

        class SingleZipReader(zipfile.ZipFile):

            def __init__(self, *args, **kwargs):

                zipfile.ZipFile.__init__(self, *args, **kwargs)

                if settings.DEBUG:

                    assert len(self.namelist()) == 1, "Zip-compressed fixtures must contain only one file."

            def read(self):

                return zipfile.ZipFile.read(self, self.namelist()[0])

        compression_types = {

            None:   file,

            'gz':   gzip.GzipFile,

            'zip':  SingleZipReader

        }

        if has_bz2:

            compression_types['bz2'] = bz2.BZ2File

        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 and parts[-1] in compression_types:

                compression_formats = [parts[-1]]

                parts = parts[:-1]

            else:

                compression_formats = compression_types.keys()

            if len(parts) == 1:

                fixture_name = parts[0]

                formats = serializers.get_public_serializer_formats()

            else:

                fixture_name, format = '.'.join(parts[:-1]), parts[-1]

                if format in serializers.get_public_serializer_formats():

                    formats = [format]

                else:

                    formats = []

            if formats:

                if verbosity > 1:

                    print "Loading '%s' fixtures..." % fixture_name

            else:

                sys.stderr.write(

                    self.style.ERROR("Problem installing fixture '%s': %s is not a known serialization format." %

                        (fixture_name, format)))

                transaction.rollback()

                transaction.leave_transaction_management()

                return

            if os.path.isabs(fixture_name):

                fixture_dirs = [fixture_name]

            else:

                fixture_dirs = app_fixtures + list(settings.FIXTURE_DIRS) + ['']

            for fixture_dir in fixture_dirs:

                if verbosity > 1:

                    print "Checking %s for fixtures..." % humanize(fixture_dir)

                label_found = False

                for format in formats:

                    for compression_format in compression_formats:

                        if compression_format: 

                            file_name = '.'.join([fixture_name, format, 

                                                  compression_format])

                        else: 

                            file_name = '.'.join([fixture_name, format])

                        if verbosity > 1:

                            print "Trying %s for %s fixture '%s'..." % \

                                (humanize(fixture_dir), file_name, fixture_name)

                        full_path = os.path.join(fixture_dir, file_name)

                        open_method = compression_types[compression_format]                                

                        try: 

                            fixture = open_method(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:

                                fixture_count += 1

                                objects_in_fixture = 0

                                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:

                                        objects_in_fixture += 1

                                        models.add(obj.object.__class__)

                                        obj.save()

                                    object_count += objects_in_fixture

                                    label_found = True

                                except (SystemExit, KeyboardInterrupt):

                                    raise

                                except Exception:

                                    import traceback

                                    fixture.close()

                                    transaction.rollback()

                                    transaction.leave_transaction_management()

                                    if show_traceback:

                                        traceback.print_exc()

                                    else:

                                        sys.stderr.write(

                                            self.style.ERROR("Problem installing fixture '%s': %s\n" %

                                                 (full_path, ''.join(traceback.format_exception(sys.exc_type, 

                                                     sys.exc_value, sys.exc_traceback))))) 

                                    return

                                fixture.close()

                                # If the fixture we loaded contains 0 objects, assume that an

                                # error was encountered during fixture loading.

                                if objects_in_fixture == 0:

                                    sys.stderr.write(

                                        self.style.ERROR("No fixture data found for '%s'. (File format may be invalid.)" %

                                            (fixture_name)))

                                    transaction.rollback()

                                    transaction.leave_transaction_management()

                                    return

                        except Exception, e:

                            if verbosity > 1:

                                print "No %s fixture '%s' in %s." % \

                                    (format, fixture_name, humanize(fixture_dir))

        # If we found even one object in a fixture, we need to reset the

        # database sequences.

        if object_count > 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)

        if commit:

            transaction.commit()

            transaction.leave_transaction_management()

        if object_count == 0:

            if verbosity > 1:

                print "No fixtures found."

        else:

            if verbosity > 0:

                print "Installed %d object(s) from %d fixture(s)" % (object_count, fixture_count)

        # Close the DB connection. This is required as a workaround for an

        # edge case in MySQL: if the same connection is used to

        # create tables, load data, and query, the query can return

        # incorrect results. See Django #7572, MySQL #37735.

        if commit:

            connection.close()