from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import select

from app.database import get_db
from app.models.user import User
from app.schemas.user import LoginRequest, Token, UserCreate, UserOut
from app.schemas.common import Response
from app.services.auth_service import (
    authenticate_user, create_access_token, hash_password,
    get_current_user, require_roles
)

router = APIRouter()


@router.post("/login", response_model=Response[Token])
async def login(body: LoginRequest, db: AsyncSession = Depends(get_db)):
    user = await authenticate_user(db, body.username, body.password)
    if not user:
        raise HTTPException(status_code=401, detail="用户名或密码错误")
    token = create_access_token({"sub": user.username})
    return Response.ok(Token(access_token=token, username=user.username, role=user.role))


@router.get("/me", response_model=Response[UserOut])
async def get_me(current_user: User = Depends(get_current_user)):
    return Response.ok(UserOut.model_validate(current_user))


@router.post("/users", response_model=Response[UserOut])
async def create_user(
    body: UserCreate,
    db: AsyncSession = Depends(get_db),
    _: User = Depends(require_roles("admin")),
):
    result = await db.execute(select(User).where(User.username == body.username))
    if result.scalar_one_or_none():
        raise HTTPException(status_code=400, detail="用户名已存在")
    user = User(
        username=body.username,
        full_name=body.full_name,
        hashed_password=hash_password(body.password),
        role=body.role,
    )
    db.add(user)
    await db.flush()
    return Response.ok(UserOut.model_validate(user))