from django.db import models


class Partner(models.Model):
    id = models.AutoField(primary_key=True)
    external_id = models.CharField()

    def __str__(self):
        return f"Partner {self.id}"


class InventoryItem(models.Model):
    id = models.AutoField(primary_key=True)
    partner = models.ForeignKey(
        Partner, related_name="Inventory", on_delete=models.CASCADE
    )


class Element(models.Model):
    id = models.AutoField(primary_key=True)
    external_id = models.CharField()
    element_id = models.CharField(max_length=100)
    photo = models.ImageField(upload_to=".")
    additional_text = models.TextField()
    
    inventory = models.ForeignKey(
        InventoryItem, related_name="Element", on_delete=models.CASCADE
    )

    def __str__(self):
        return f"Element {self.id} (Inventory {self.inventory.id})"