from django.db import models
from django.contrib.auth.models import BaseUserManager, AbstractBaseUser, AbstractUser, UserManager


# The custom User uses email as the unique identifier, and requires
# that every user provide a date of birth. This lets us test
# changes in username datatype, and non-text required fields.

class CustomUserManager(BaseUserManager):
    def create_user(self, email, date_of_birth, password=None):
        """
        Creates and saves a User with the given email and password.
        """
        if not email:
            raise ValueError('Users must have an email address')

        user = self.model(
            email=CustomUserManager.normalize_email(email),
            date_of_birth=date_of_birth,
        )

        user.set_password(password)
        user.save(using=self._db)
        return user

    def create_superuser(self, username, password, date_of_birth):
        u = self.create_user(username, password=password, date_of_birth=date_of_birth)
        u.is_admin = True
        u.save(using=self._db)
        return u


class CustomUser(AbstractBaseUser):
    email = models.EmailField(verbose_name='email address', max_length=255, unique=True)
    is_active = models.BooleanField(default=True)
    is_admin = models.BooleanField(default=False)
    date_of_birth = models.DateField()

    objects = CustomUserManager()

    USERNAME_FIELD = 'email'
    REQUIRED_FIELDS = ['date_of_birth']

    class Meta:
        app_label = 'auth'

    def get_full_name(self):
        return self.email

    def get_short_name(self):
        return self.email

    def __unicode__(self):
        return self.email

    # Maybe required?
    def get_group_permissions(self, obj=None):
        return set()

    def get_all_permissions(self, obj=None):
        return set()

    def has_perm(self, perm, obj=None):
        return True

    def has_perms(self, perm_list, obj=None):
        return True

    def has_module_perms(self, app_label):
        return True

    # Admin required fields
    @property
    def is_staff(self):
        return self.is_admin


# The extension user is a simple extension of the built-in user class,
# adding a required date_of_birth field. This allows us to check for
# any hard references to the name "User" in forms/handlers etc.

class ExtensionUser(AbstractUser):
    date_of_birth = models.DateField()

    objects = UserManager()

    REQUIRED_FIELDS = AbstractUser.REQUIRED_FIELDS + ['date_of_birth']

    class Meta:
        app_label = 'auth'