"""
C-Stone Invoice Check — Auth Router
JWT Token Endpoints
"""

from fastapi import APIRouter, Depends, HTTPException, status
from fastapi.security import OAuth2PasswordRequestForm
from sqlalchemy.orm import Session
from datetime import timedelta

from backend.database import get_db
from backend.auth import (
    authenticate_user,
    create_access_token,
    get_password_hash,
    ACCESS_TOKEN_EXPIRE_MINUTES
)
from backend.schemas import Token, UserCreate, UserResponse

router = APIRouter()


@router.post("/token", response_model=Token)
async def login_for_access_token(
    form_data: OAuth2PasswordRequestForm = Depends(),
    db: Session = Depends(get_db)
):
    """OAuth2 Token Endpoint - Login mit Benutzername/Passwort"""
    user = authenticate_user(db, form_data.username, form_data.password)
    if not user:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Falscher Benutzername oder Passwort",
            headers={"WWW-Authenticate": "Bearer"},
        )
    access_token_expires = timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
    access_token = create_access_token(
        data={"sub": user.username},
        expires_delta=access_token_expires
    )
    return {"access_token": access_token, "token_type": "bearer"}


@router.post("/register", response_model=UserResponse)
async def register_user(user: UserCreate, db: Session = Depends(get_db)):
    """Neuen Benutzer registrieren"""
    from backend.models import User

    # Prüfen ob Benutzer existiert
    existing = db.query(User).filter(User.username == user.username).first()
    if existing:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Benutzername existiert bereits"
        )

    # Benutzer erstellen
    hashed_password = get_password_hash(user.password)
    db_user = User(
        username=user.username,
        hashed_password=hashed_password,
        is_active=True
    )
    db.add(db_user)
    db.commit()
    db.refresh(db_user)

    return db_user


@router.get("/me", response_model=UserResponse)
async def read_users_me(
    current_user: UserResponse = Depends(lambda: None)  # TODO: Implementierung
):
    """Aktuellen Benutzer abrufen"""
    raise HTTPException(
        status_code=status.HTTP_501_NOT_IMPLEMENTED,
        detail="Endpoint noch nicht implementiert"
    )