app/api/auth.py

"""
Authentication endpoints.

POST /auth/register — create a user account (email + password + role).
                      Duplicate email returns HTTP 409.
POST /auth/login    — validate credentials and return a signed JWT.
                      Rate-limited to 10 requests/minute per IP to slow
                      brute-force attacks.
"""

from datetime import datetime

from fastapi import APIRouter, Depends, HTTPException, Request, status
from pydantic import BaseModel
from sqlmodel import Session, select

from app.config import settings
from app.deps import get_db
from app.limiter import limiter
from app.models.db import User, UserRole
from app.security import hash_password, verify_password, create_access_token

router = APIRouter()


class RegisterRequest(BaseModel):
    email: str
    password: str
    role: UserRole = UserRole.user


class RegisterResponse(BaseModel):
    id: str
    email: str
    role: str
    created_at: datetime


class LoginRequest(BaseModel):
    email: str
    password: str


class LoginResponse(BaseModel):
    access_token: str
    token_type: str
    role: str


@router.post("/register", response_model=RegisterResponse, status_code=201)
def register(req: RegisterRequest, db: Session = Depends(get_db)):
    existing = db.exec(select(User).where(User.email == req.email)).first()
    if existing:
        raise HTTPException(status_code=status.HTTP_409_CONFLICT, detail="Email already registered")

    user = User(
        email=req.email,
        hashed_password=hash_password(req.password),
        role=req.role,
        created_at=datetime.utcnow(),
    )
    db.add(user)
    db.commit()
    db.refresh(user)

    return RegisterResponse(
        id=str(user.id),
        email=user.email,
        role=user.role.value,
        created_at=user.created_at,
    )


@router.post("/login", response_model=LoginResponse)
@limiter.limit("10/minute")
def login(request: Request, req: LoginRequest, db: Session = Depends(get_db)):
    user = db.exec(select(User).where(User.email == req.email)).first()
    if not user or not verify_password(req.password, user.hashed_password):
        raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED, detail="Invalid credentials")
    if not user.is_active:
        raise HTTPException(status_code=status.HTTP_401_UNAUTHORIZED, detail="Account is inactive")

    token = create_access_token(
        data={"sub": str(user.id), "role": user.role.value},
        expires_minutes=settings.ACCESS_TOKEN_EXPIRE_MINUTES,
    )
    return LoginResponse(access_token=token, token_type="bearer", role=user.role.value)