from fastapi import APIRouter, HTTPException, Depends
from pydantic import BaseModel
import db
import auth

router = APIRouter()

class UserAuth(BaseModel):
    username: str
    password: str

@router.post("/api/register")
def register(user: UserAuth):
    if not user.username or not user.password:
        raise HTTPException(status_code=400, detail="用户名和密码不能为空")
    if len(user.username) < 3 or len(user.username) > 20:
        raise HTTPException(status_code=400, detail="用户名长度需在3-20个字符之间")
    if len(user.password) < 6:
        raise HTTPException(status_code=400, detail="密码长度至少6个字符")
        
    existing_user = db.get_user_by_username(user.username)
    if existing_user:
        raise HTTPException(status_code=400, detail="用户名已存在")
        
    hashed_password = auth.get_password_hash(user.password)
    new_user = db.create_user({"username": user.username, "password": hashed_password})
    
    return {"message": "注册成功", "userId": new_user["id"]}

@router.post("/api/login")
def login(user: UserAuth):
    if not user.username or not user.password:
        raise HTTPException(status_code=400, detail="用户名和密码不能为空")
        
    db_user = db.get_user_by_username(user.username)
    if not db_user:
        raise HTTPException(status_code=401, detail="用户名或密码错误")
        
    if not auth.verify_password(user.password, db_user["password"]):
        raise HTTPException(status_code=401, detail="用户名或密码错误")
        
    token = auth.create_access_token({"id": db_user["id"], "username": db_user["username"]})
    return {
        "message": "登录成功",
        "token": token,
        "user": {"id": db_user["id"], "username": db_user["username"]}
    }

@router.get("/api/me")
def get_me(current_user: dict = Depends(auth.get_current_user)):
    return {"user": {"id": current_user["id"], "username": current_user["username"]}}

@router.post("/api/logout")
def logout():
    return {"message": "已退出登录"}