from __future__ import annotations

import enum
from datetime import datetime

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

from app.db.base_class import Base


class AchievementType(enum.Enum):
    COMPLETION = "completion"  # Complete lessons/quizzes
    STREAK = "streak"  # Maintain a daily learning streak
    PERFORMANCE = "performance"  # Get high scores or perfect quizzes
    MILESTONE = "milestone"  # Reach specific milestones (points, levels)
    SPECIAL = "special"  # Special or seasonal achievements


class Achievement(Base):
    """
    Achievement model for defining available achievements in the system.
    """

    id = Column(Integer, primary_key=True, index=True)
    name = Column(String, index=True, nullable=False)
    description = Column(Text, nullable=False)
    type = Column(Enum(AchievementType), nullable=False)
    image_url = Column(String, nullable=True)
    points = Column(Integer, default=0)  # Points awarded for earning this achievement
    criteria = Column(Text, nullable=False)  # JSON string with criteria for earning
    is_active = Column(Boolean, default=True)
    created_at = Column(DateTime, default=datetime.utcnow)
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)

    # Relationships
    user_achievements = relationship("UserAchievement", back_populates="achievement")


class UserAchievement(Base):
    """
    UserAchievement model for tracking achievements earned by users.
    """

    id = Column(Integer, primary_key=True, index=True)
    user_id = Column(Integer, ForeignKey("user.id"), nullable=False)
    achievement_id = Column(Integer, ForeignKey("achievement.id"), nullable=False)
    earned_at = Column(DateTime, default=datetime.utcnow)

    # Relationships
    user = relationship("User", back_populates="achievements")
    achievement = relationship("Achievement", back_populates="user_achievements")

    # This ensures that a user can only earn a specific achievement once
    __table_args__ = (
        # UniqueConstraint('user_id', 'achievement_id', name='user_achievement_uc'),
    )