project-managment/src/tickets/models.py

import random
import string

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


def generate_ticket_uuid(prefix):
    rand = "".join(random.choices(string.ascii_uppercase + string.digits, k=6))
    return f"{prefix}-{rand}"


class TicketPriority(models.Model):
    name = models.CharField(max_length=255, unique=True)
    color = models.CharField(max_length=7, default="#6B7280")
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = "ticket_priorities"
        verbose_name = "Ticket Priority"
        verbose_name_plural = "Ticket Priorities"
        indexes = [
            models.Index(fields=["name"]),
        ]

    def __str__(self):
        return self.name


class TicketStatus(models.Model):
    project = models.ForeignKey(
        "projects.Project", on_delete=models.CASCADE, related_name="ticket_statuses"
    )
    name = models.CharField(max_length=255)
    color = models.CharField(max_length=7, default="#10B981")
    sort_order = models.IntegerField(default=0)
    is_completed = models.BooleanField(default=False)
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = "ticket_statuses"
        verbose_name = "Ticket Status"
        verbose_name_plural = "Ticket Statuses"
        indexes = [
            models.Index(fields=["project", "sort_order"]),
            models.Index(fields=["project", "is_completed"]),
            models.Index(fields=["project", "name"]),
        ]

    def __str__(self):
        return f"[{self.project.ticket_prefix}] {self.name}"


class Ticket(models.Model):
    project = models.ForeignKey(
        "projects.Project", on_delete=models.CASCADE, related_name="tickets"
    )
    status = models.ForeignKey(
        TicketStatus, on_delete=models.CASCADE, related_name="tickets"
    )
    epic = models.ForeignKey(
        "epics.Epic",
        on_delete=models.SET_NULL,
        blank=True,
        null=True,
        related_name="tickets",
    )
    priority = models.ForeignKey(
        TicketPriority,
        on_delete=models.SET_NULL,
        blank=True,
        null=True,
        related_name="tickets",
    )
    name = models.CharField(max_length=255)
    description = models.TextField(blank=True, null=True)
    uuid = models.CharField(max_length=255, unique=True, editable=False)
    start_date = models.DateField(blank=True, null=True)
    due_date = models.DateField(blank=True, null=True)
    created_by = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.SET_NULL,
        blank=True,
        null=True,
        related_name="created_tickets",
    )
    assignees = models.ManyToManyField(
        settings.AUTH_USER_MODEL,
        through="TicketUser",
        related_name="assigned_tickets",
    )
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = "tickets"
        verbose_name = "Ticket"
        verbose_name_plural = "Tickets"
        indexes = [
            models.Index(fields=["project", "status"]),
            models.Index(fields=["status", "created_at"]),
            models.Index(fields=["project", "created_at"]),
            models.Index(fields=["project", "updated_at"]),
            models.Index(fields=["due_date"]),
            models.Index(fields=["priority"]),
            models.Index(fields=["created_by"]),
            models.Index(fields=["epic"]),
            models.Index(fields=["name"]),
            models.Index(fields=["start_date"]),
            models.Index(fields=["project", "name"]),
            models.Index(fields=["project", "start_date", "due_date"]),
            models.Index(fields=["due_date", "status"]),
        ]

    def __str__(self):
        return f"{self.uuid} - {self.name}"

    def save(self, *args, **kwargs):
        if not self.uuid:
            self.uuid = generate_ticket_uuid(self.project.ticket_prefix)
        super().save(*args, **kwargs)


class TicketUser(models.Model):
    ticket = models.ForeignKey(
        Ticket, on_delete=models.CASCADE, related_name="ticket_assignees"
    )
    user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = "ticket_users"
        verbose_name = "Ticket Assignee"
        verbose_name_plural = "Ticket Assignees"
        constraints = [
            models.UniqueConstraint(
                fields=["ticket", "user"], name="unique_ticket_user"
            )
        ]
        indexes = [
            models.Index(fields=["ticket", "user"]),
            models.Index(fields=["user"]),
        ]

    def __str__(self):
        return f"{self.user} -> {self.ticket}"


class TicketHistory(models.Model):
    ticket = models.ForeignKey(
        Ticket, on_delete=models.CASCADE, related_name="histories"
    )
    user = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.CASCADE,
        related_name="ticket_histories",
    )
    status = models.ForeignKey(
        TicketStatus, on_delete=models.CASCADE, related_name="histories"
    )
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = "ticket_histories"
        verbose_name = "Ticket History"
        verbose_name_plural = "Ticket Histories"
        indexes = [
            models.Index(fields=["ticket", "created_at"]),
            models.Index(fields=["user", "created_at"]),
        ]

    def __str__(self):
        return f"{self.ticket.uuid} -> {self.status.name} by {self.user}"


class TicketComment(models.Model):
    ticket = models.ForeignKey(
        Ticket, on_delete=models.CASCADE, related_name="comments"
    )
    user = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.CASCADE,
        related_name="ticket_comments",
    )
    parent = models.ForeignKey(
        "self", on_delete=models.CASCADE, null=True, blank=True, related_name="replies"
    )
    comment = models.TextField(help_text="Rich text HTML content")
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

    class Meta:
        db_table = "ticket_comments"
        verbose_name = "Ticket Comment"
        verbose_name_plural = "Ticket Comments"
        indexes = [
            models.Index(fields=["ticket", "created_at"]),
            models.Index(fields=["user"]),
        ]

    def __str__(self):
        return f"Comment by {self.user} on {self.ticket.uuid}"