"""Authentication endpoints for API v1."""
from fastapi import APIRouter, Depends, HTTPException, status, Request
from fastapi.security import OAuth2PasswordRequestForm
from sqlalchemy.orm import Session
from typing import List

from backend.models.user import User
from backend import auth
from backend.schemas.user import UserCreate, UserResponse
from backend.schemas.token import Token
from backend.database import get_db
from backend.core.config import settings
from slowapi import Limiter
from slowapi.util import get_remote_address

router = APIRouter(prefix="/api/auth", tags=["authentication"])
limiter = Limiter(key_func=get_remote_address)


@router.post("/register", response_model=UserResponse, status_code=status.HTTP_201_CREATED)
@limiter.limit(f"{settings.RATE_LIMIT_TIMES}/{settings.RATE_LIMIT_SECONDS}s")
def register(request: Request, user: UserCreate, db: Session = Depends(get_db)):
    """Register a new user."""
    db_user = db.query(User).filter(User.username == user.username).first()
    if db_user:
        raise HTTPException(status_code=400, detail="Username already registered")
    
    hashed_password = auth.get_password_hash(user.password)
    new_user = User(username=user.username, hashed_password=hashed_password)
    db.add(new_user)
    db.commit()
    db.refresh(new_user)
    return new_user


@router.post("/token", response_model=Token)
@limiter.limit(f"{settings.RATE_LIMIT_TIMES}/{settings.RATE_LIMIT_SECONDS}s")
def login_for_access_token(
    request: Request,
    form_data: OAuth2PasswordRequestForm = Depends(),
    db: Session = Depends(get_db)
):
    """Login and get access token."""
    user = db.query(User).filter(User.username == form_data.username).first()
    if not user or not auth.verify_password(form_data.password, user.hashed_password):
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Incorrect username or password",
            headers={"WWW-Authenticate": "Bearer"},
        )
    
    from datetime import timedelta
    access_token_expires = timedelta(minutes=settings.ACCESS_TOKEN_EXPIRE_MINUTES)
    access_token = auth.create_access_token(
        data={"sub": user.username}, expires_delta=access_token_expires
    )
    return {"access_token": access_token, "token_type": "bearer"}


@router.get("/me", response_model=UserResponse)
def read_users_me(current_user: User = Depends(auth.get_current_user)):
    """Get current user information."""
    return current_user