from pgvector.sqlalchemy import Vector
from sqlalchemy import Column, Integer, String, Text, JSON, ForeignKey
from sqlalchemy.orm import relationship, deferred

from app.config import settings
from app.database import Base
from app.models.question_category import QuestionCategory  # noqa — ensures mapper resolves
from app.models.quiz_question_link import QuizQuestionLink  # noqa


class Question(Base):
    __tablename__ = "questions"

    id = Column(Integer, primary_key=True, index=True)
    # source_quiz_id: which quiz this question was originally extracted for (informational).
    # Content membership is tracked via quiz_question_links junction table.
    source_quiz_id = Column("quiz_id", Integer, ForeignKey("quizzes.id", ondelete="SET NULL"), nullable=True)
    question_category_id = Column(Integer, ForeignKey("question_categories.id", ondelete="SET NULL"), nullable=True)
    question_text = Column(Text, nullable=False)
    question_type = Column(String, nullable=False)  # mcq, true_false, fill_blank
    options = Column(JSON, nullable=True)  # list of strings for mcq
    correct_answer = Column(String, nullable=False)
    explanation = Column(Text, nullable=True)
    page_reference = Column(Integer, nullable=True)
    image_path = Column(String, nullable=True)
    user_id = Column(Integer, ForeignKey("users.id", ondelete="SET NULL"), nullable=True)
    is_shared = Column(Integer, default=1)  # 1 = visible in bank, 0 = private (only owner sees it)
    embedding = deferred(Column(Vector(1024), nullable=True))  # semantic search vector — deferred: not loaded in standard queries

    question_category = relationship("QuestionCategory", back_populates="questions",
                                     foreign_keys=[question_category_id])
