from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.orm import Session
from pydantic import BaseModel, Field

from ..database import get_db
from .. import models
from ..auth import hash_password, verify_password, create_access_token

router = APIRouter()


class UserCreate(BaseModel):
    username: str = Field(min_length=3, max_length=50)
    password: str = Field(min_length=8)


class UserLogin(BaseModel):
    username: str
    password: str


class Token(BaseModel):
    access_token: str
    token_type: str
    is_admin: bool


@router.post("/register", status_code=status.HTTP_201_CREATED)
def register(user_in: UserCreate, db: Session = Depends(get_db)):
    existing = db.query(models.User).filter(models.User.username == user_in.username).first()
    if existing:
        raise HTTPException(status_code=400, detail="Username already taken")
    no_users_yet = db.query(models.User).first() is None
    user = models.User(
        username=user_in.username,
        password=hash_password(user_in.password),
        is_admin=no_users_yet,
    )
    db.add(user)
    db.commit()
    return {"message": "User created"}


@router.post("/login", response_model=Token)
def login(user_in: UserLogin, db: Session = Depends(get_db)):
    user = db.query(models.User).filter(models.User.username == user_in.username).first()
    if not user or not verify_password(user_in.password, user.password):
        raise HTTPException(status_code=401, detail="Invalid credentials")
    token = create_access_token({"sub": user.username})
    return {"access_token": token, "token_type": "bearer", "is_admin": user.is_admin}