from datetime import datetime
from sqlalchemy import DateTime, Float, ForeignKey, Integer, String, Text, UniqueConstraint
from sqlalchemy.orm import Mapped, mapped_column, relationship
from .database import Base


class Student(Base):
    __tablename__ = "students"

    id: Mapped[int] = mapped_column(Integer, primary_key=True, index=True)
    first_name: Mapped[str] = mapped_column(String(100))
    age: Mapped[int] = mapped_column(Integer)
    grade: Mapped[str] = mapped_column(String(50))
    created_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow)

    messages = relationship("Message", back_populates="student", cascade="all, delete-orphan")
    mastery = relationship("StudentSkillMastery", back_populates="student", cascade="all, delete-orphan")


class Message(Base):
    __tablename__ = "messages"

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    student_id: Mapped[int] = mapped_column(ForeignKey("students.id"), index=True)
    role: Mapped[str] = mapped_column(String(20))
    content: Mapped[str] = mapped_column(Text)
    created_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow)

    student = relationship("Student", back_populates="messages")


class Skill(Base):
    __tablename__ = "skills"

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    code: Mapped[str] = mapped_column(String(100), unique=True)
    subject: Mapped[str] = mapped_column(String(50))
    label: Mapped[str] = mapped_column(String(255))
    description: Mapped[str] = mapped_column(Text)


class StudentSkillMastery(Base):
    __tablename__ = "student_skill_mastery"
    __table_args__ = (UniqueConstraint("student_id", "skill_id", name="uq_student_skill"),)

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    student_id: Mapped[int] = mapped_column(ForeignKey("students.id"), index=True)
    skill_id: Mapped[int] = mapped_column(ForeignKey("skills.id"), index=True)
    mastery_score: Mapped[float] = mapped_column(Float, default=50.0)
    confidence: Mapped[float] = mapped_column(Float, default=0.2)
    evidence_count: Mapped[int] = mapped_column(Integer, default=0)
    updated_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)

    student = relationship("Student", back_populates="mastery")
    skill = relationship("Skill")


class AssessmentAttempt(Base):
    __tablename__ = "assessment_attempts"

    id: Mapped[int] = mapped_column(Integer, primary_key=True)
    student_id: Mapped[int] = mapped_column(ForeignKey("students.id"), index=True)
    skill_code: Mapped[str] = mapped_column(String(100), index=True)
    question: Mapped[str] = mapped_column(Text)
    expected_answer: Mapped[str] = mapped_column(Text)
    student_answer: Mapped[str] = mapped_column(Text)
    is_correct: Mapped[int] = mapped_column(Integer)
    feedback: Mapped[str] = mapped_column(Text)
    created_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow)