from fastapi import APIRouter, HTTPException

users = [
    {
        "username": "admin",
        "password": "securepassword"
    }
]

router = APIRouter()

@router.get("/auth")
async def authenticate_user(
    username: str = "admin",
    password: str = "securepassword"
):
    """authenticates the user"""
    user = next((u for u in users if u["username"] == username), None)
    if not user or user["password"] != password:
        raise HTTPException(status_code=400, detail="Invalid credentials")

    return {
        "method": "GET",
        "_verb": "get",
        "message": "Authentication successful",
        "user": username,
        "token": "dummy_jwt_token_456"
    }