from datetime import datetime
from flask_login import UserMixin
from app.extensions import db, login_manager


class User(UserMixin, db.Model):
    __tablename__ = 'users'

    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(64), unique=True, nullable=False, index=True)
    email = db.Column(db.String(128), unique=True, nullable=False, index=True)
    password_hash = db.Column(db.String(255), nullable=False)
    role = db.Column(db.Enum('admin', 'user'), nullable=False, default='user')
    is_active = db.Column(db.Boolean, default=True, nullable=False)
    avatar = db.Column(db.String(255), nullable=True)
    created_at = db.Column(db.DateTime, default=datetime.utcnow, nullable=False)
    last_login = db.Column(db.DateTime, nullable=True)

    # 关联资源
    resources = db.relationship('Resource', backref='owner', lazy='dynamic',
                                cascade='all, delete-orphan')

    def __repr__(self):
        return f'<User {self.username}>'

    @property
    def is_admin(self):
        return self.role == 'admin'

    def get_id(self):
        return str(self.id)


@login_manager.user_loader
def load_user(user_id):
    return db.session.get(User, int(user_id))