function checkLogin(state){
    if(state.data.username == "admin"){
        return {
            ...state,
            transitionTo: "valid"
        };
    }else {
        return {
            ...state,
            transitionTo: "invalid"
        };
    }
}

function showLogin(state){
    return {
        data : {
            ...state.data,
            message: "Logged in as " + state.data.username,
        },
        transitionTo: "done"
    };
}

function showError(state){
    return {
        data : {
            ...state.data,
            message: "Username " + state.data.username + " is invalid"
        },
        transitionTo: "done"
    };
}

let fsmRunner = {
    "checkLogin": checkLogin,
    "showLogin" : showLogin,
    "showError" : showError
};