from datetime import timedelta
from typing import Any

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

from app import crud
from app.api import deps
from app.core import security
from app.core.config import settings
from app.schemas.token import Token
from app.schemas.user import User, UserCreate

router = APIRouter()


@router.post("/register", response_model=User)
def register(
    *,
    db: Session = Depends(deps.get_db),
    user_in: UserCreate,
) -> Any:
    """
    Register a new user.
    """
    user = crud.user.get_by_email(db, email=user_in.email)
    if user:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="A user with this email already exists",
        )
    
    user = crud.user.get_by_username(db, username=user_in.username)
    if user:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="A user with this username already exists",
        )
    
    user = crud.user.create(db, obj_in=user_in)
    return user


@router.post("/login", response_model=Token)
def login_access_token(
    db: Session = Depends(deps.get_db),
    form_data: OAuth2PasswordRequestForm = Depends(),
) -> Any:
    """
    OAuth2 compatible token login, get an access token for future requests.
    """
    user = crud.user.authenticate(
        db, email=form_data.username, password=form_data.password
    )
    if not user:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Incorrect email or password",
        )
    if not crud.user.is_active(user):
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST, detail="Inactive user"
        )
    
    access_token_expires = timedelta(minutes=settings.ACCESS_TOKEN_EXPIRE_MINUTES)
    
    return {
        "access_token": security.create_access_token(
            user.id, expires_delta=access_token_expires
        ),
        "token_type": "bearer",
    }