using System;
using Unity.Netcode;
using Unity.Services.Multiplayer;
using UnityEngine;
using UnityEngine.SceneManagement;
using UnityEngine.UI;
using TMPro;

public class MainMenuUIController : MonoBehaviour
{
    [Header("Buttons")]
    [SerializeField] private Button hostButton;
    [SerializeField] private Button clientButton;

    [Header("Join by code")]
    [SerializeField] private TMP_InputField joinCodeInput;

    [Header("Feedback")]
    [SerializeField] private TMP_Text joinCodeDisplay;   // показывает код созданной сессии
    [SerializeField] private TMP_Text statusText;        // статус/ошибки
    [SerializeField] private Button copyCodeButton;      // копирование кода в буфер обмена

    [Header("Session")]
    [SerializeField] private int maxPlayers = 2;
    [SerializeField] private string sessionType = "dev-game";
    [SerializeField] private string gameSceneName = "DEV-Game";

    private ISession session;
    private bool isBusy;

    private void Awake()
    {
        hostButton.onClick.AddListener(OnHostClicked);
        clientButton.onClick.AddListener(OnJoinClicked);

        if (copyCodeButton != null)
        {
            copyCodeButton.onClick.AddListener(CopyCode);
            copyCodeButton.gameObject.SetActive(false);
        }
    }

    private void OnDestroy()
    {
        hostButton.onClick.RemoveListener(OnHostClicked);
        clientButton.onClick.RemoveListener(OnJoinClicked);

        if (copyCodeButton != null)
            copyCodeButton.onClick.RemoveListener(CopyCode);
    }

    private void CopyCode()
    {
        if (string.IsNullOrEmpty(SessionInfo.JoinCode)) return;

        GUIUtility.systemCopyBuffer = SessionInfo.JoinCode;
        SetStatus($"Code copied: {SessionInfo.JoinCode}");
    }

    private async void OnHostClicked()
    {
        if (isBusy) return;
        SetBusy(true);
        SetStatus("Creating session...");

        try
        {
            SessionOptions _options = new SessionOptions
            {
                Name = $"session-{Guid.NewGuid().ToString().Substring(0, 6)}",
                MaxPlayers = maxPlayers,
                Type = sessionType
            };
            _options.WithRelayNetwork();

            // Sessions API сам поднимает Relay и запускает NetworkManager как host
            session = await MultiplayerService.Instance.CreateSessionAsync(_options);

            SessionInfo.JoinCode = session.Code;

            if (joinCodeDisplay != null) joinCodeDisplay.text = session.Code;
            if (copyCodeButton != null) copyCodeButton.gameObject.SetActive(true);
            SetStatus($"Hosting. Code: {session.Code}");
            Debug.Log($"Session created. Join code: {session.Code}");

            // Хост грузит игровую сцену — клиентам она синхронизируется автоматически.
            // Код сохранён в SessionInfo и показывается уже в игре (SessionCodeView).
            NetworkManager.Singleton.SceneManager.LoadScene(gameSceneName, LoadSceneMode.Single);
        }
        catch (Exception _e)
        {
            SetStatus($"Host failed: {_e.Message}");
            Debug.LogException(_e);
            SetBusy(false);
        }
    }

    private async void OnJoinClicked()
    {
        if (isBusy) return;

        string _code = joinCodeInput != null ? joinCodeInput.text.Trim() : string.Empty;
        if (string.IsNullOrEmpty(_code))
        {
            SetStatus("Enter a join code first");
            return;
        }

        SetBusy(true);
        SetStatus($"Joining {_code}...");

        try
        {
            JoinSessionOptions _options = new JoinSessionOptions { Type = sessionType };

            // Подключение к Relay и запуск NetworkManager как client — автоматически.
            // Игровая сцена придёт от хоста через сетевую синхронизацию сцен.
            session = await MultiplayerService.Instance.JoinSessionByCodeAsync(_code, _options);

            SessionInfo.JoinCode = _code;
            SetStatus("Joined. Waiting for host scene...");
            Debug.Log($"Joined session {session.Id}");
        }
        catch (Exception _e)
        {
            SetStatus($"Join failed: {_e.Message}");
            Debug.LogException(_e);
            SetBusy(false);
        }
    }

    private void SetBusy(bool _busy)
    {
        isBusy = _busy;
        hostButton.interactable = !_busy;
        clientButton.interactable = !_busy;
    }

    private void SetStatus(string _text)
    {
        if (statusText != null) statusText.text = _text;
    }
}