from datetime import datetime, timedelta, timezone

from fastapi import APIRouter, Depends, HTTPException
from jose import jwt
import bcrypt
from sqlalchemy.orm import Session

from app.config import JWT_ALGORITHM, JWT_EXPIRATION_HOURS, JWT_SECRET_KEY
from app.database import get_db
from app.models.user import AdminUser
from app.schemas.auth import LoginRequest, TokenResponse

router = APIRouter(prefix="/auth", tags=["认证"])


def verify_password(plain_password: str, hashed_password: str) -> bool:
    """验证密码"""
    return bcrypt.checkpw(plain_password.encode(), hashed_password.encode())


def create_access_token(data: dict) -> str:
    """创建 JWT token"""
    to_encode = data.copy()
    expire = datetime.now(timezone.utc) + timedelta(hours=JWT_EXPIRATION_HOURS)
    to_encode.update({"exp": expire})
    encoded_jwt = jwt.encode(to_encode, JWT_SECRET_KEY, algorithm=JWT_ALGORITHM)
    return encoded_jwt


@router.post("/login", response_model=TokenResponse)
def login(req: LoginRequest, db: Session = Depends(get_db)):
    """管理员登录"""
    user = db.query(AdminUser).filter(AdminUser.username == req.username).first()
    if not user or not verify_password(req.password, user.password_hash):
        raise HTTPException(status_code=401, detail="用户名或密码错误")
    access_token = create_access_token(data={"sub": str(user.id), "username": user.username})
    return TokenResponse(access_token=access_token)