from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import select
from ..database import get_db
from ..models.user import User
from ..schemas.user import UserCreate, UserLogin, UserResponse, Token
from ..utils.security import get_password_hash, verify_password, create_access_token
from ..services.auth import get_current_user

router = APIRouter(prefix="/api/auth", tags=["auth"])


@router.post("/register", response_model=Token)
async def register(user_data: UserCreate, db: AsyncSession = Depends(get_db)):
    # Check if email exists
    result = await db.execute(select(User).where(User.email == user_data.email))
    if result.scalar_one_or_none():
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Email already registered",
        )

    # Check if username exists
    result = await db.execute(select(User).where(User.username == user_data.username))
    if result.scalar_one_or_none():
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Username already taken",
        )

    # Create user
    user = User(
        username=user_data.username,
        email=user_data.email,
        password_hash=get_password_hash(user_data.password),
    )
    db.add(user)
    await db.flush()

    # Create token
    access_token = create_access_token(data={"sub": str(user.id)})
    return Token(access_token=access_token)


@router.post("/login", response_model=Token)
async def login(user_data: UserLogin, db: AsyncSession = Depends(get_db)):
    result = await db.execute(select(User).where(User.email == user_data.email))
    user = result.scalar_one_or_none()

    if not user or not verify_password(user_data.password, user.password_hash):
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail="Invalid email or password",
        )

    access_token = create_access_token(data={"sub": str(user.id)})
    return Token(access_token=access_token)


@router.get("/me", response_model=UserResponse)
async def get_me(current_user: User = Depends(get_current_user)):
    return current_user