38 lines
1.5 KiB
Python
38 lines
1.5 KiB
Python
from django.db import models
|
|
from .category import FormulaCategory
|
|
from users.models import User
|
|
from django.utils import timezone
|
|
from .symbol import Symbol
|
|
|
|
class Formula(models.Model):
|
|
formula_id = models.CharField(max_length=100)
|
|
title = models.CharField(max_length=255)
|
|
description = models.TextField(blank=True)
|
|
meta = models.TextField(blank=True)
|
|
category = models.ForeignKey(FormulaCategory, on_delete=models.PROTECT)
|
|
tags = models.JSONField(default=list)
|
|
latex = models.TextField()
|
|
raw_latex = models.TextField()
|
|
symbols = models.ManyToManyField(Symbol, related_name='formulas')
|
|
calculator = models.CharField(max_length=100)
|
|
revision = models.PositiveIntegerField(default=1)
|
|
code = models.CharField(max_length=10, unique=True)
|
|
created_by = models.ForeignKey(User, on_delete=models.SET_NULL, null=True)
|
|
created_at = models.DateTimeField(default=timezone.now)
|
|
|
|
|
|
def save(self, *args, **kwargs):
|
|
if not self.code:
|
|
base_prefix = f"{self.category.prefix:02d}"
|
|
existing_codes = Formula.objects.filter(category=self.category).values_list('code', flat=True)
|
|
index = 1
|
|
while True:
|
|
proposed_code = f"{base_prefix}{index:02d}{self.revision:02d}"
|
|
if proposed_code not in existing_codes:
|
|
self.code = proposed_code
|
|
break
|
|
index += 1
|
|
super().save(*args, **kwargs)
|
|
|
|
def __str__(self):
|
|
return f"{self.title} ({self.code})" |