Aetheria/Assets/Scripts/UI/LoginScreen.cs

using System;
using System.Collections;
using System.Collections.Generic;
using TMPro;
using UnityEngine;
using UnityEngine.SceneManagement;

public class LoginScreen : MonoBehaviour
{
    public FlatButton LoginButton;
    public FlatButton RegisterButton;
    public TMP_InputField Server;
    public TMP_InputField EmailUsername;
    public TMP_InputField Email;
    public TMP_InputField Username;
    public TMP_InputField Password;
    public TextMeshProUGUI Error;

    private bool _registering;
    
    void Start()
    {
        Error.text = " ";
        LoginButton.CurrentState = FlatButtonState.Selected;
        CultClient.AddMessageListener<LoginSuccessMessage>(success => SceneManager.LoadScene("Main"));
        CultClient.OnError += s => Error.text = s;
        RegisterButton.OnClick += () =>
        {
            if(!CultClient.Connected)
                CultClient.Connect(Server.text);
            if (_registering)
            {
                CultClient.Register(Email.text, Username.text, Password.text);
            }
            else
            {
                _registering = true;
                EmailUsername.gameObject.SetActive(false);
                Email.gameObject.SetActive(true);
                Username.gameObject.SetActive(true);
                LoginButton.CurrentState = FlatButtonState.Unselected;
                RegisterButton.CurrentState = FlatButtonState.Selected;
            }
        };
        LoginButton.OnClick += () =>
        {
            if(!CultClient.Connected)
                CultClient.Connect(Server.text);
            if (_registering)
            {
                _registering = false;
                EmailUsername.gameObject.SetActive(true);
                Email.gameObject.SetActive(false);
                Username.gameObject.SetActive(false);
                LoginButton.CurrentState = FlatButtonState.Selected;
                RegisterButton.CurrentState = FlatButtonState.Unselected;
            }
            else
            {
                CultClient.Login(EmailUsername.text, Password.text);
            }
        };
    }

    private void Update()
    {
        if (Input.GetKeyDown(KeyCode.Tab) || Input.GetKeyDown(KeyCode.Return))
        {
            if (Server.isFocused)
            {
                if(_registering)
                    Email.Select();
                else EmailUsername.Select();
            }
            else if (EmailUsername.isFocused)
                Password.Select();
            else if (Email.isFocused)
                Username.Select();
            else if (Username.isFocused)
                Password.Select();
            else if (Password.isFocused && Input.GetKeyDown(KeyCode.Return))
                (_registering ? RegisterButton : LoginButton).OnPointerClick(null);
        }
    }
}