from datetime import datetime

from sqlalchemy import Column, Integer, Boolean, String, DateTime, ForeignKey, JSON
from sqlalchemy.orm import relationship

from app.database import Base


class QuizAttempt(Base):
    __tablename__ = "quiz_attempts"

    id = Column(Integer, primary_key=True, index=True)
    quiz_id = Column(Integer, ForeignKey("quizzes.id", ondelete="CASCADE"), nullable=False)
    user_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
    mode = Column(String(10), nullable=True)  # legacy NULL resumes without exposing answers
    score = Column(Integer, default=0)
    total_questions = Column(Integer, default=0)
    started_at = Column(DateTime, default=datetime.utcnow)
    completed_at = Column(DateTime, nullable=True)
    selected_question_ids = Column(JSON, nullable=True)  # for question pool: which questions this attempt uses
    expired = Column(Integer, default=0)  # 1 = auto-submitted due to timer expiry (abandoned), excluded from history

    quiz = relationship("Quiz", back_populates="attempts")
    user = relationship("User", back_populates="attempts")
    answers = relationship("AttemptAnswer", back_populates="attempt", cascade="all, delete-orphan")


class AttemptAnswer(Base):
    __tablename__ = "attempt_answers"

    id = Column(Integer, primary_key=True, index=True)
    attempt_id = Column(Integer, ForeignKey("quiz_attempts.id", ondelete="CASCADE"), nullable=False)
    question_id = Column(Integer, ForeignKey("questions.id", ondelete="CASCADE"), nullable=False)
    user_answer = Column(String, nullable=False)
    # Seconds on this question. Null means an answer from before this was
    # measured, which is not the same claim as zero.
    seconds_spent = Column(Integer, nullable=True)
    is_correct = Column(Boolean, default=False)
    # Whether a tip was opened on this question before it was answered. Rows
    # written before tips existed carry 0, which is not a guess: there was
    # nothing to open.
    used_hint = Column(Boolean, nullable=False, default=False, server_default="0")

    attempt = relationship("QuizAttempt", back_populates="answers")
    question = relationship("Question")