import uuid
from django.conf import settings
from django.db import models


class ProcessingBatch(models.Model):
    class Grade(models.TextChoices):
        A = "A", "Grade A"
        B = "B", "Grade B"
        C = "C", "Grade C"

    class Status(models.TextChoices):
        HARVESTED = "harvested", "Harvested"
        PROCESSING = "processing", "Processing"
        QC_PASS = "qc_pass", "QC Pass"
        QC_FAIL = "qc_fail", "QC Fail"
        READY_TO_SHIP = "ready_to_ship", "Ready to Ship"
        IN_TRANSIT = "in_transit", "In Transit"
        AT_UK_PORT = "at_uk_port", "At UK Port"
        CUSTOMS = "customs", "Customs"
        DELIVERED = "delivered", "Delivered"

    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    batch_reference = models.CharField(max_length=50, unique=True)
    harvest_date = models.DateField(null=True, blank=True)
    weight_kg = models.DecimalField(max_digits=10, decimal_places=2, null=True, blank=True)
    grade = models.CharField(max_length=5, choices=Grade.choices, null=True, blank=True)
    status = models.CharField(max_length=20, choices=Status.choices, default=Status.HARVESTED)
    origin_facility = models.CharField(max_length=255, default="ASI - Katsina State, Nigeria")
    notes = models.TextField(blank=True)
    created_by = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.SET_NULL, null=True, related_name="batches_created")
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = "processing_batches"
        ordering = ["-created_at"]

    def __str__(self):
        return self.batch_reference