from django.contrib.auth.base_user import AbstractBaseUser, BaseUserManager
from django.contrib.auth.models import PermissionsMixin
from django.db import models
from django.db.models import BooleanField, CharField, EmailField

from engagements.models import Engagement


class Common(models.Model):
    date_created = models.DateTimeField(auto_now_add=True)
    last_modified = models.DateTimeField(auto_now=True)

    class Meta:
        abstract = True


class TeamMgr(BaseUserManager):
    def create_user(self, email, password=None):
        if not email:
            raise ValueError("Users must have an email address")
        user = self.model(
            email=self.normalize_email(email),
        )
        user.set_password(password)
        user.save(using=self._db)
        return user

    def create_superuser(self, email, password=None):
        user = self.create_user(
            email,
            password=password,
        )
        user.is_admin = True
        user.save(using=self._db)
        return user


class Team(Common):
    name = models.CharField(max_length=256)

    def __str__(self):
        return self.name


class TeamUser(AbstractBaseUser, PermissionsMixin):
    """
    The `TeamUser` class is a custom user model that extends the `AbstractBaseUser` and `PermissionsMixin` classes from Django's built-in authentication system. It provides a user model with the following fields:

    - `email`: The user's email address, which is used as the unique identifier for the user.
    - `first_name`: The user's first name (optional).
    - `last_name`: The user's last name (optional).
    - `dapsy`: A boolean field indicating whether the user is a DAPSY user.
    - `is_active`: A boolean field indicating whether the user is active.
    - `is_admin`: A boolean field indicating whether the user is an admin.
    - `team`: A foreign key relationship to the `Team` model, indicating the team the user belongs to.
    - `lead_for`: A many-to-many relationship to the `engagements.Organisation` model, indicating the organizations the user is a lead inspector for.
    - `designation`: The user's designation (optional).

    The `TeamUser` class also overrides the default user manager with the `TeamMgr` class, which provides custom methods for creating regular and superuser accounts.

    The `__str__` method returns the user's email address, and the `fullname` method returns the user's full name (first and last name).

    The `has_perm` and `has_module_perms` methods are placeholders that always return `True`, indicating that the user has all permissions. The `is_staff` property is also a placeholder that returns the value of `is_admin`.
    """

    email = EmailField(verbose_name="email address", max_length=255, unique=True)
    first_name = CharField(max_length=20, null=True, blank=True)
    last_name = CharField(max_length=20, null=True, blank=True)
    dapsy = BooleanField(default=False)
    is_active = BooleanField(default=True)
    is_admin = BooleanField(default=False)
    team = models.ForeignKey(Team, null=True, on_delete=models.CASCADE, related_name="team_members")
    lead_for = models.ManyToManyField("engagements.Organisation", blank=True, related_name="lead_inspector")
    designation = models.CharField(max_length=3, null=True, blank=True)

    USERNAME_FIELD = "email"
    # EMAIL_FIELD = "email"

    objects = TeamMgr()

    def __str__(self):
        return self.email

    def get_all_engagements(self):
        return Engagement.objects.filter(officers__id__contains=self.id)

    def fullname(self):
        return f"{self.first_name} {self.last_name}"

    def has_perm(self, perm, obj=None):
        "Does this user have a specific permission? Set True for now."
        return True

    def has_module_perms(self, app_label):
        "Does user have permissions to view the app `app_label`? Yes for now."
        return True

    @property
    def is_staff(self):
        return self.is_admin