from django.contrib.contenttypes import generic
from django.contrib.contenttypes.models import ContentType
from django.conf import settings
from django.db import models
from django.db import connection, DEFAULT_DB_ALIAS


class Square(models.Model):
    root = models.IntegerField()
    square = models.PositiveIntegerField()

    def __unicode__(self):
        return "%s ** 2 == %s" % (self.root, self.square)


class Person(models.Model):
    first_name = models.CharField(max_length=20)
    last_name = models.CharField(max_length=20)

    def __unicode__(self):
        return u'%s %s' % (self.first_name, self.last_name)


class SchoolClass(models.Model):
    year = models.PositiveIntegerField()
    day = models.CharField(max_length=9, blank=True)
    last_updated = models.DateTimeField()

# Unfortunately, the following model breaks MySQL hard.
# Until #13711 is fixed, this test can't be run under MySQL.
if connection.features.supports_long_model_names:
    class VeryLongModelNameZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZ(models.Model):
        class Meta:
            # We need to use a short actual table name or
            # we hit issue #8548 which we're not testing!
            verbose_name = 'model_with_long_table_name'
        primary_key_is_quite_long_zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz = models.AutoField(primary_key=True)
        charfield_is_quite_long_zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz = models.CharField(max_length=100)
        m2m_also_quite_long_zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz = models.ManyToManyField(Person,blank=True)


class Tag(models.Model):
    name = models.CharField(max_length=30)
    content_type = models.ForeignKey(ContentType, related_name='backend_tags')
    object_id = models.PositiveIntegerField()
    content_object = generic.GenericForeignKey('content_type', 'object_id')


class Post(models.Model):
    name = models.CharField(max_length=30)
    text = models.TextField()
    tags = generic.GenericRelation('Tag')

    class Meta:
        db_table = 'CaseSensitive_Post'