用户登录功能

backend/models.py

@@ -1,9 +1,34 @@
 from flask_sqlalchemy import SQLAlchemy
 from datetime import datetime
 from sqlalchemy import func
+from werkzeug.security import generate_password_hash, check_password_hash
 
 db = SQLAlchemy()
 
+class User(db.Model):
+    """用户模型"""
+    __tablename__ = 'users'
+
+    id = db.Column(db.Integer, primary_key=True)
+    username = db.Column(db.String(80), unique=True, nullable=False)
+    password_hash = db.Column(db.String(200), nullable=False)
+    created_at = db.Column(db.DateTime, default=datetime.utcnow)
+
+    def set_password(self, password):
+        """设置密码（哈希加密）"""
+        self.password_hash = generate_password_hash(password)
+
+    def check_password(self, password):
+        """验证密码"""
+        return check_password_hash(self.password_hash, password)
+
+    def to_dict(self):
+        return {
+            'id': self.id,
+            'username': self.username,
+            'created_at': self.created_at.isoformat() if self.created_at else None
+        }
+
 class Task(db.Model):
     """任务模型"""
     __tablename__ = 'tasks'