from django.db import models


class OutboxMail(models.Model):
    """One e-mail waiting to be sent, being sent, sent or failed. Owned by `mailer` (AD-19)."""

    class Status(models.TextChoices):
        QUEUED = "queued"
        SENDING = "sending"
        SENT = "sent"
        FAILED = "failed"

    template = models.CharField(max_length=100)
    recipient = models.CharField(max_length=254)
    subject = models.CharField(max_length=300)
    # Kept only until the mail is sent: it may hold a one-time link.
    body_text = models.TextField(blank=True)
    status = models.CharField(max_length=10, choices=Status.choices, default=Status.QUEUED)
    attempts = models.PositiveSmallIntegerField(default=0)
    created_at = models.DateTimeField()
    next_attempt_at = models.DateTimeField()
    claimed_at = models.DateTimeField(null=True, blank=True)
    sent_at = models.DateTimeField(null=True, blank=True)
    # What went wrong, in words without the recipient or the text of the mail.
    last_error = models.CharField(max_length=200, blank=True)

    class Meta:
        indexes = [models.Index(fields=["status", "next_attempt_at"])]
        ordering = ["id"]