from django.db import models
from .quiz_user_model import QuizUser
from .quiz_session_model import QuizSession
from .question_model import Question


class QuizResult(models.Model):
    user = models.ForeignKey(QuizUser, on_delete=models.CASCADE, related_name='results')
    quiz_session = models.ForeignKey(QuizSession, on_delete=models.CASCADE, related_name='results', null=True, blank=True)
    question = models.ForeignKey(Question, on_delete=models.CASCADE)
    selected_answer = models.CharField(max_length=1)
    is_correct = models.BooleanField()
    difficulty = models.CharField(max_length=10, blank=True, null=True, choices=[
        ('again', 'Again'),
        ('hard', 'Hard'),
        ('good', 'Good'),
        ('easy', 'Easy'),
    ])
    answered_at = models.DateTimeField(auto_now_add=True)

    class Meta:
        unique_together = ['user', 'question']

    def __str__(self):
        return f"{self.user} - {self.question.text[:30]} - {'✓' if self.is_correct else '✗'}"