from django.contrib.auth.models import AbstractBaseUser, BaseUserManager, PermissionsMixin
from django.db import models


class EmailUserManager(BaseUserManager):
    """Custom user manager using email as the unique identifier."""

    def create_user(self, email, password=None, **extra_fields):
        if not email:
            raise ValueError("Email is required")
        email = self.normalize_email(email)
        user = self.model(email=email, **extra_fields)
        user.set_password(password)
        user.save(using=self._db)
        return user

    def create_superuser(self, email, password=None, **extra_fields):
        extra_fields.setdefault("is_staff", True)
        extra_fields.setdefault("is_superuser", True)
        return self.create_user(email, password, **extra_fields)


class EmailUser(AbstractBaseUser, PermissionsMixin):
    """Minimal user model with email as USERNAME_FIELD.

    Matches the calling convention used in djarea's test suite:
        User.objects.create_user(email="...", password="...", is_staff=True)
    """

    email = models.EmailField(unique=True)
    is_staff = models.BooleanField(default=False)
    is_active = models.BooleanField(default=True)

    objects = EmailUserManager()

    USERNAME_FIELD = "email"
    REQUIRED_FIELDS = []

    class Meta:
        app_label = "tests"


# ─── Shape test models ──────────────────────────────────────────────────────


class Author(models.Model):
    name = models.CharField(max_length=100)
    bio = models.TextField(blank=True, default="")

    class Meta:
        app_label = "tests"

    def __str__(self):
        return self.name


class Book(models.Model):
    title = models.CharField(max_length=200)
    pages = models.IntegerField(default=0)
    author = models.ForeignKey(Author, on_delete=models.CASCADE, related_name="books")

    class Meta:
        app_label = "tests"

    def __str__(self):
        return self.title


class Tag(models.Model):
    name = models.CharField(max_length=50)
    books = models.ManyToManyField(Book, related_name="tags", blank=True)

    class Meta:
        app_label = "tests"