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

from app.db import get_db
from app.models.user import User
from app.schemas import RegisterRequest, UserOut
from app.security import hash_password

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


@router.post("/register", response_model=UserOut, status_code=status.HTTP_201_CREATED)
async def register(payload: RegisterRequest, db: AsyncSession = Depends(get_db)):
    existing = await db.scalar(select(User).where(User.username == payload.username))
    if existing is not None:
        raise HTTPException(status_code=status.HTTP_409_CONFLICT, detail="username taken")

    user = User(
        username=payload.username,
        password_hash=hash_password(payload.password),
        email=payload.email,
    )
    db.add(user)
    await db.commit()
    await db.refresh(user)
    return user