"""
Management utility to create superusers.
"""

import getpass
import sys
from optparse import make_option

from django.contrib.auth import get_user_model
from django.contrib.auth.management import get_default_username
from django.core import exceptions
from django.core.management.base import BaseCommand, CommandError
from django.db import DEFAULT_DB_ALIAS
from django.utils.six.moves import input
from django.utils.text import capfirst


class Command(BaseCommand):
    option_list = BaseCommand.option_list + (
        make_option('--username', dest='username', default=None,
            help='Specifies the username for the superuser.'),
        make_option('--noinput', action='store_false', dest='interactive', default=True,
            help=('Tells Django to NOT prompt the user for input of any kind. '
                  'You must use --username with --noinput, along with an option for '
                  'any other required field. Superusers created with --noinput will '
                  ' not be able to log in until they\'re given a valid password.')),
        make_option('--database', action='store', dest='database',
            default=DEFAULT_DB_ALIAS, help='Specifies the database to use. Default is "default".'),
    ) + tuple(
        make_option('--%s' % field, dest=field, default=None,
            help='Specifies the %s for the superuser.' % field)
        for field in get_user_model().REQUIRED_FIELDS
    )

    help = 'Used to create a superuser.'

    def handle(self, *args, **options):
        username = options.get('username', None)
        interactive = options.get('interactive')
        verbosity = int(options.get('verbosity', 1))
        database = options.get('database')

        UserModel = get_user_model()

        username_field = UserModel._meta.get_field(getattr(UserModel, 'USERNAME_FIELD', 'username'))
        other_fields = UserModel.REQUIRED_FIELDS

        # If not provided, create the user with an unusable password
        password = None
        other_data = {}

        # Do quick and dirty validation if --noinput
        if not interactive:
            try:
                if not username:
                    raise CommandError("You must use --username with --noinput.")
                username = username_field.clean(username, None)

                for field_name in other_fields:
                    if options.get(field_name):
                        field = UserModel._meta.get_field(field_name)
                        other_data[field_name] = field.clean(options[field_name], None)
                    else:
                        raise CommandError("You must use --%s with --noinput." % field_name)
            except exceptions.ValidationError as e:
                raise CommandError('; '.join(e.messages))

        else:
            # Prompt for username/password, and any other required fields.
            # Enclose this whole thing in a try/except to trap for a
            # keyboard interrupt and exit gracefully.
            default_username = get_default_username()
            try:

                # Get a username
                while username is None:
                    username_field = UserModel._meta.get_field(getattr(UserModel, 'USERNAME_FIELD', 'username'))
                    if not username:
                        input_msg = capfirst(username_field.verbose_name)
                        if default_username:
                            input_msg += " (leave blank to use '%s')" % default_username
                        raw_value = input(input_msg + ': ')

                    if default_username and raw_value == '':
                        raw_value = default_username
                    try:
                        username = username_field.clean(raw_value, None)
                    except exceptions.ValidationError as e:
                        self.stderr.write("Error: %s" % '; '.join(e.messages))
                        username = None
                        continue
                    try:
                        UserModel.objects.using(database).get(**{
                                getattr(UserModel, 'USERNAME_FIELD', 'username'): username
                            })
                    except UserModel.DoesNotExist:
                        pass
                    else:
                        self.stderr.write("Error: That username is already taken.")
                        username = None

                for field_name in other_fields:
                    field = UserModel._meta.get_field(field_name)
                    other_data[field_name] = options.get(field_name)
                    while other_data[field_name] is None:
                        raw_value = input(capfirst(field.verbose_name + ': '))
                        try:
                            other_data[field_name] = field.clean(raw_value, None)
                        except exceptions.ValidationError as e:
                            self.stderr.write("Error: %s" % '; '.join(e.messages))
                            other_data[field_name] = None

                # Get a password
                while password is None:
                    if not password:
                        password = getpass.getpass()
                        password2 = getpass.getpass('Password (again): ')
                        if password != password2:
                            self.stderr.write("Error: Your passwords didn't match.")
                            password = None
                            continue
                    if password.strip() == '':
                        self.stderr.write("Error: Blank passwords aren't allowed.")
                        password = None
                        continue

            except KeyboardInterrupt:
                self.stderr.write("\nOperation cancelled.")
                sys.exit(1)

        UserModel.objects.db_manager(database).create_superuser(username=username, password=password, **other_data)
        if verbosity >= 1:
            self.stdout.write("Superuser created successfully.")