from sqlalchemy import Column, Integer, String, DateTime, Boolean, Text, ForeignKey, Numeric, JSON
from sqlalchemy.orm import relationship
from sqlalchemy.sql import func
from .database import Base

class User(Base):
    __tablename__ = "users"

    id = Column(Integer, primary_key=True, index=True)
    email = Column(String(255), unique=True, index=True, nullable=False)
    hashed_password = Column(String(255), nullable=False)
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    is_active = Column(Boolean, default=True)
    is_developer = Column(Boolean, default=False)

    favorite_courses = relationship("FavoriteCourse", back_populates="user", cascade="all, delete-orphan")
    progress = relationship("Progress", back_populates="user", cascade="all, delete-orphan")

class Course(Base):
    __tablename__ = "courses"

    id = Column(Integer, primary_key=True, index=True)
    title = Column(String(255), nullable=False)
    description = Column(Text, nullable=False)
    level = Column(String(50), nullable=False)
    duration = Column(Integer, default=0, nullable=False)
    content = Column(Text)
    author_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
    status = Column(String(20), default='draft', nullable=False)
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    updated_at = Column(DateTime(timezone=True), server_default=func.now(), onupdate=func.now())

    author = relationship("User")
    modules = relationship("CourseModule", back_populates="course", cascade="all, delete-orphan")
    favorites = relationship("FavoriteCourse", back_populates="course", cascade="all, delete-orphan")
    progress_records = relationship("Progress", back_populates="course", cascade="all, delete-orphan")


class CourseModule(Base):
    __tablename__ = "course_modules"

    id = Column(Integer, primary_key=True, index=True)
    course_id = Column(Integer, ForeignKey("courses.id", ondelete="CASCADE"), nullable=False)
    title = Column(String(255), nullable=False)
    description = Column(Text)
    duration = Column(String(100))  # e.g., "2 weeks", "10 hours"
    order_index = Column(Integer, default=0, nullable=False)
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    updated_at = Column(DateTime(timezone=True), server_default=func.now(), onupdate=func.now())

    course = relationship("Course", back_populates="modules")
    lessons = relationship("Lesson", back_populates="module", cascade="all, delete-orphan")


class Lesson(Base):
    __tablename__ = "lessons"

    id = Column(Integer, primary_key=True, index=True)
    module_id = Column(Integer, ForeignKey("course_modules.id", ondelete="CASCADE"), nullable=False)
    title = Column(String(255), nullable=False)
    description = Column(Text)
    order_index = Column(Integer, default=0, nullable=False)
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    updated_at = Column(DateTime(timezone=True), server_default=func.now(), onupdate=func.now())

    module = relationship("CourseModule", back_populates="lessons")
    steps = relationship("LessonStep", back_populates="lesson", cascade="all, delete-orphan")


class LessonStep(Base):
    __tablename__ = "lesson_steps"

    id = Column(Integer, primary_key=True, index=True)
    lesson_id = Column(Integer, ForeignKey("lessons.id", ondelete="CASCADE"), nullable=False)
    step_type = Column(String(50), nullable=False)
    title = Column(String(255))
    content = Column(Text)
    content_html = Column(Text)
    file_url = Column(String(500))
    test_settings = Column(JSON)  # {passing_score, max_attempts, time_limit, show_answers}
    order_index = Column(Integer, default=0, nullable=False)
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    updated_at = Column(DateTime(timezone=True), server_default=func.now(), onupdate=func.now())

    lesson = relationship("Lesson", back_populates="steps")
    test_questions = relationship("TestQuestion", back_populates="step", cascade="all, delete-orphan")
    test_attempts = relationship("TestAttempt", back_populates="step", cascade="all, delete-orphan")


class FavoriteCourse(Base):
    __tablename__ = "favorite_courses"

    user_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), primary_key=True)
    course_id = Column(Integer, ForeignKey("courses.id", ondelete="CASCADE"), primary_key=True)
    added_at = Column(DateTime(timezone=True), server_default=func.now())

    user = relationship("User", back_populates="favorite_courses")
    course = relationship("Course", back_populates="favorites")


class Progress(Base):
    __tablename__ = "progress"
    
    user_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), primary_key=True)
    course_id = Column(Integer, ForeignKey("courses.id", ondelete="CASCADE"), primary_key=True)
    completed_lessons = Column(Integer, default=0, nullable=False)
    total_lessons = Column(Integer, default=0, nullable=False)
    updated_at = Column(DateTime(timezone=True), server_default=func.now(), onupdate=func.now())
    
    user = relationship("User", back_populates="progress")
    course = relationship("Course")


class CourseDraft(Base):
    __tablename__ = "course_drafts"
    
    id = Column(Integer, primary_key=True, index=True)
    user_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
    title = Column(String(255), nullable=False)
    description = Column(Text)
    level = Column(String(50), nullable=False)
    content = Column(Text, nullable=False)
    structure = Column(Text)  # JSON строка для структуры модулей
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    updated_at = Column(DateTime(timezone=True), server_default=func.now(), onupdate=func.now())
    
    user = relationship("User")


class TestQuestion(Base):
    __tablename__ = "test_questions"
    
    id = Column(Integer, primary_key=True, index=True)
    step_id = Column(Integer, ForeignKey("lesson_steps.id", ondelete="CASCADE"), nullable=False)
    question_text = Column(Text, nullable=False)
    question_type = Column(String(50), nullable=False)  # single_choice, multiple_choice, text_answer, match
    points = Column(Integer, default=1)
    order_index = Column(Integer, default=0)
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    updated_at = Column(DateTime(timezone=True), server_default=func.now(), onupdate=func.now())
    
    step = relationship("LessonStep", back_populates="test_questions")
    answers = relationship("TestAnswer", back_populates="question", cascade="all, delete-orphan")
    match_items = relationship("TestMatchItem", back_populates="question", cascade="all, delete-orphan")


class TestAnswer(Base):
    __tablename__ = "test_answers"
    
    id = Column(Integer, primary_key=True, index=True)
    question_id = Column(Integer, ForeignKey("test_questions.id", ondelete="CASCADE"), nullable=False)
    answer_text = Column(Text, nullable=False)
    is_correct = Column(Boolean, default=False)
    order_index = Column(Integer, default=0)
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    
    question = relationship("TestQuestion", back_populates="answers")


class TestMatchItem(Base):
    __tablename__ = "test_match_items"
    
    id = Column(Integer, primary_key=True, index=True)
    question_id = Column(Integer, ForeignKey("test_questions.id", ondelete="CASCADE"), nullable=False)
    left_text = Column(Text, nullable=False)
    right_text = Column(Text, nullable=False)
    order_index = Column(Integer, default=0)
    created_at = Column(DateTime(timezone=True), server_default=func.now())
    
    question = relationship("TestQuestion", back_populates="match_items")


class TestAttempt(Base):
    __tablename__ = "test_attempts"
    
    id = Column(Integer, primary_key=True, index=True)
    user_id = Column(Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
    step_id = Column(Integer, ForeignKey("lesson_steps.id", ondelete="CASCADE"), nullable=False)
    score = Column(Numeric(5, 2))
    max_score = Column(Numeric(5, 2))
    passed = Column(Boolean, default=False)
    answers = Column(JSON)  # {question_id: answer_id или [answer_ids] или text или {left_id: right_id}}
    started_at = Column(DateTime(timezone=True), server_default=func.now())
    completed_at = Column(DateTime(timezone=True))
    
    user = relationship("User")
    step = relationship("LessonStep", back_populates="test_attempts")