app/models/quiz.py

"""Quiz and assessment models."""

from datetime import datetime
from enum import Enum as PyEnum
from sqlalchemy import Column, String, Boolean, DateTime, Text, Integer, ForeignKey, Float, JSON
from sqlalchemy.orm import relationship
from uuid import uuid4
from app.database import Base


class QuestionType(str, PyEnum):
    MULTIPLE_CHOICE = "multiple_choice"
    TRUE_FALSE = "true_false"
    SHORT_ANSWER = "short_answer"


class Quiz(Base):
    __tablename__ = "quizzes"

    id = Column(String(36), primary_key=True, default=lambda: str(uuid4()))
    lesson_id = Column(String(36), ForeignKey("lessons.id"), nullable=False)
    title = Column(String(255), nullable=False)
    description = Column(Text, nullable=True)
    passing_score = Column(Float, default=70.0)
    time_limit_minutes = Column(Integer, nullable=True)
    max_attempts = Column(Integer, default=3)
    is_ai_generated = Column(Boolean, default=False)
    is_published = Column(Boolean, default=False)

    # Timestamps
    created_at = Column(DateTime, default=datetime.utcnow)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)

    # Relationships
    lesson = relationship("Lesson", back_populates="quizzes")
    questions = relationship("QuizQuestion", back_populates="quiz", cascade="all, delete-orphan")
    attempts = relationship("QuizAttempt", back_populates="quiz", cascade="all, delete-orphan")

    def __repr__(self):
        return f"<Quiz {self.title}>"


class QuizQuestion(Base):
    __tablename__ = "quiz_questions"

    id = Column(String(36), primary_key=True, default=lambda: str(uuid4()))
    quiz_id = Column(String(36), ForeignKey("quizzes.id"), nullable=False)
    question_type = Column(String(50), default=QuestionType.MULTIPLE_CHOICE)
    question_text = Column(Text, nullable=False)
    options = Column(JSON, nullable=True)  # List of options for MCQ
    correct_answer = Column(Text, nullable=False)
    explanation = Column(Text, nullable=True)
    points = Column(Integer, default=1)
    order_index = Column(Integer, default=0)

    # Relationships
    quiz = relationship("Quiz", back_populates="questions")

    def __repr__(self):
        return f"<QuizQuestion {self.id}>"


class QuizAttempt(Base):
    __tablename__ = "quiz_attempts"

    id = Column(String(36), primary_key=True, default=lambda: str(uuid4()))
    quiz_id = Column(String(36), ForeignKey("quizzes.id"), nullable=False)
    student_id = Column(String(36), ForeignKey("users.id"), nullable=False)
    score = Column(Float, default=0.0)
    passed = Column(Boolean, default=False)
    answers = Column(JSON, nullable=True)  # Student's answers
    time_taken_seconds = Column(Integer, nullable=True)

    # Timestamps
    started_at = Column(DateTime, default=datetime.utcnow)
    completed_at = Column(DateTime, nullable=True)

    # Relationships
    quiz = relationship("Quiz", back_populates="attempts")
    student = relationship("User", back_populates="quiz_attempts")

    def __repr__(self):
        return f"<QuizAttempt {self.student_id} -> {self.quiz_id}>"