import sys

from django.db import connections
from django.db.utils import ConnectionDoesNotExist, IntegrityError
from django.core.management.base import BaseCommand

from django_comments.models import Comment

from django_comments_xtd.models import XtdComment


__all__ = ['Command']


class Command(BaseCommand):
    help = "Load the xtdcomment table with valid data from django_comments."

    def add_arguments(self, parser):
        parser.add_argument('using', nargs='*', type=str)

    def populate_db(self, cursor):
        for comment in Comment.objects.all():
            sql = ("INSERT INTO %(table)s "
                   "       ('comment_ptr_id', 'thread_id', 'parent_id',"
                   "        'level', 'order', 'followup') "
                   "VALUES (%(id)d, %(id)d, %(id)d, 0, 1, 0)")
            cursor.execute(sql % {'table': XtdComment._meta.db_table,
                                  'id': comment.id})

    def handle(self, *args, **options):
        total = 0
        using = options['using'] or ['default']
        for db_conn in using:
            try:
                self.populate_db(connections[db_conn].cursor())
                total += XtdComment.objects.using(db_conn).count()
            except ConnectionDoesNotExist:
                print("DB connection '%s' does not exist." % db_conn)
                continue
            except IntegrityError:
                if db_conn != 'default':
                    print("Table '%s' (in '%s' DB connection) must be empty."
                          % (XtdComment._meta.db_table, db_conn))
                else:
                    print("Table '%s' must be empty."
                          % XtdComment._meta.db_table)
                sys.exit(1)
        print("Added %d XtdComment object(s)." % total)