# coding=utf-8
from django.db import models
from django.contrib.auth.models import BaseUserManager, AbstractBaseUser


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

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

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

    def create_superuser(self, email, username, date_of_birth, password):
        """
        Creates and saves a superuser with the given email, date of
        birth and password.
        :param username:
        :param email:
        :param password:
        :param date_of_birth:
        """
        user = self.create_user(email,
                                username=username,
                                password=password,
                                date_of_birth=date_of_birth
                                )
        user.is_admin = True
        user.save(using=self._db)
        return user


class CustomUser(AbstractBaseUser):
    # Fields
    email = models.EmailField(verbose_name='email address', max_length=96, unique=True)

    username = models.TextField(max_length=32, unique=True)
    first_name = models.TextField(max_length=24, db_index=True, blank=True, null=True)
    last_name = models.TextField(max_length=24, db_index=True, blank=True, null=True)
    date_of_birth = models.DateField()

    is_active = models.BooleanField(default=True)
    is_admin = models.BooleanField(default=False)
    subscribed_on = models.DateTimeField(auto_now_add=True, db_index=True)
    # End fields

    objects = CustomUserManager()

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

    def get_full_name(self):
        # The user is identified by their email address
        return self.email

    def get_short_name(self):
        # The user is identified by their email address
        return self.email

    def __str__(self):  # __unicode__ on Python 2
        return self.email

    def has_perm(self, perm, obj=None):
        "Does the user have a specific permission?"
        # Simplest possible answer: Yes, always
        return True

    def has_module_perms(self, app_label):
        "Does the user have permissions to view the app `app_label`?"
        # Simplest possible answer: Yes, always
        return True

    @property
    def is_staff(self):
        "Is the user a member of staff?"
        # Simplest possible answer: All admins are staff
        return self.is_admin


class CustomGroup(models.Model):
    """
    Custom user group
    """
    name = models.CharField(max_length=48, unique=True)
    boss = models.ForeignKey(CustomUser, related_name='groups_owned')
    members = models.ManyToManyField(CustomUser, through='CustomUserInGroup')

    def __unicode__(self):
        return self.name


class CustomUserInGroup(models.Model):
    """
    Link between CustomUser and CustomGroup
    """
    group = models.ForeignKey(CustomGroup, related_name='customs')
    custom = models.ForeignKey(CustomUser, related_name='groups')
    joined_on = models.DateTimeField(auto_now_add=True, blank=True, null=True)

    class Meta:
        unique_together = ('group','custom')

    def __unicode__(self):
        return "{} in {}".format(self.custom, self.group)