from django.contrib.auth import get_user_model
from django.db import models
from django_extensions.db.models import TimeStampedModel

from books.models import Module


class Assignment(TimeStampedModel):
    title = models.CharField(max_length=255)
    assignment = models.TextField()
    deleted = models.BooleanField(default=False)
    owner = models.ForeignKey(get_user_model(),
                              on_delete=models.PROTECT)  # probably don't want to delete all assignments if a user gets deleted
    module = models.ForeignKey(Module, related_name='assignments', on_delete=models.CASCADE)

    def __str__(self):
        return self.title


class CustomAssignment(Assignment):
    pass


class StudentSubmission(TimeStampedModel):
    text = models.TextField(blank=True)
    document = models.URLField(blank=True, default='', max_length=255)
    assignment = models.ForeignKey(Assignment, on_delete=models.CASCADE, related_name='submissions')
    student = models.ForeignKey(get_user_model(), on_delete=models.CASCADE)
    final = models.BooleanField(default=False)