from django.contrib.auth.models import User
from django.db import models
from django.conf import settings

class ColorChoices(models.TextChoices):
    RED = "Red", "Red"
    BLUE = "Blue", "Blue"
    GREEN = "Green", "Green"
    BLACK = "Black", "Black"
    WHITE = "White", "White"

class SizeChoices(models.TextChoices):
    SMALL = "S", "Small"
    MEDIUM = "M", "Medium"
    LARGE = "L", "Large"
    XLARGE = "XL", "X-Large"

class Color(models.Model):
    name = models.CharField(max_length=10, choices=ColorChoices.choices, unique=True)

    def __str__(self):
        return self.name

class Size(models.Model):
    name = models.CharField(max_length=5, choices=SizeChoices.choices, unique=True)

    def __str__(self):
        return self.name

class Product(models.Model):
    title = models.CharField(max_length=200)
    image = models.ImageField(upload_to="products/", null=True, blank=True)
    price = models.DecimalField(max_digits=10, decimal_places=2, default=0.00)

    # Use string references to prevent circular imports
    colors = models.ManyToManyField("shop.Color", blank=True, related_name="products")
    sizes = models.ManyToManyField("shop.Size", blank=True, related_name="products")

    def __str__(self):
        return self.title

class CartItem(models.Model):
    user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, null=True, blank=True)
    product = models.ForeignKey(Product, on_delete=models.CASCADE)
    quantity = models.PositiveIntegerField(default=1)
    session_id = models.CharField(max_length=255, null=True, blank=True)
    date_added = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return f"{self.quantity} x {self.product.title}"

    def get_total_price(self):
        return self.product.price * self.quantity