using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;
using BaseGames.Core;
using BaseGames.Core.Assets;
using BaseGames.Core.Events;

namespace BaseGames.UI
{
    /// <summary>
    /// 暂停菜单控制器（架构 10_UIModule §5）。
    /// 挂载在 Canvas_Menu → PauseMenuPanel GameObject 上。
    /// 按钮绑定在 Awake 中完成；由 UIManager 负责面板开关。
    /// </summary>
    public class PauseMenuController : MonoBehaviour, IFocusable
    {
        // UIManager 通过 ServiceLocator 解析，开启时自动获取，无需 Inspector 直接绑定具体类型
        private IUIManager _uiManager;

        [Header("按钮引用")]
        [SerializeField] private Button _btnResume;
        [SerializeField] private Button _btnSettings;
        [SerializeField] private Button _btnMainMenu;
        [SerializeField] private Button _btnQuit;

        [Header("Event Channels")]
        [SerializeField] private VoidEventChannelSO                _onResumeRequested;
        [SerializeField] private SceneLoadRequestEventChannelSO    _onSceneLoadRequest;

        private void Awake()
        {
            _btnResume?.onClick.AddListener(Resume);
            _btnSettings?.onClick.AddListener(OpenSettings);
            _btnMainMenu?.onClick.AddListener(GoToMainMenu);
            _btnQuit?.onClick.AddListener(Application.Quit);
        }

        private void OnEnable()
        {
            // 暂停面板由 UIManager 开启，此时 ServiceLocator 已就绪
            _uiManager = ServiceLocator.GetOrDefault<IUIManager>();
            // 手柄导航：打开时将焦点置于第一个按钮
            EventSystem.current?.SetSelectedGameObject(_btnResume?.gameObject);
        }

        private void OnDisable()
        {
            _uiManager = null;
        }

        // ── 按钮回调 ──────────────────────────────────────────────────────────

        private void Resume()
        {
            _onResumeRequested?.Raise();
            _uiManager?.CloseTopPanel();
        }

        private void OpenSettings()
        {
            _uiManager?.OpenPanel(PanelId.Settings);
        }

        private void GoToMainMenu()
        {
            _uiManager?.CloseTopPanel();
            _onSceneLoadRequest?.Raise(new SceneLoadRequest
            {
                SceneName         = AddressKeys.SceneMainMenu,
                TransitionType    = TransitionType.Scene,
                ShowLoadingScreen = false,
            });
        }

        // ── IFocusable ────────────────────────────────────────────────────────

        /// <summary>面板恢复为栈顶时（关闭子面板后）自动移回第一个按鈕。</summary>
        public void OnFocusRestored()
            => EventSystem.current?.SetSelectedGameObject(_btnResume?.gameObject);
    }
}