using System.Collections.Generic;
using UnityEngine;
using BaseGames.Core.Assets;
using BaseGames.Core.Events;
using BaseGames.UI.MainMenu;   // 复用通用菜单按钮视图 MainMenuButtonView

namespace BaseGames.UI
{
    /// <summary>
    /// 数据驱动暂停菜单（仿 <see cref="MainMenu.DataDrivenMainMenuController"/>）。
    /// 据 <see cref="PauseMenuConfigSO"/> 在运行时生成按钮、派发动作；生命周期/焦点/淡入由 <see cref="UIPanelBase"/> 统一处理。
    /// 策划改 UI_PauseMenuConfig 即可增删/重排/改标签/改动作，零代码；样式改 UI_PauseScreen / UI_MainMenu_Button 预制件。
    /// </summary>
    public class DataDrivenPauseMenuController : UIPanelBase
    {
        [Header("数据表 / 按钮列表")]
        [SerializeField] private PauseMenuConfigSO  _config;
        [Tooltip("按钮的父节点（通常挂 VerticalLayoutGroup）。")]
        [SerializeField] private Transform          _container;
        [SerializeField] private MainMenuButtonView _buttonPrefab;

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

        private IUIManager _uiManager;
        private readonly List<MainMenuButtonView> _buttons = new();
        private MainMenuButtonView _firstButton;

        // 暂停面板由 UIManager 开启，此时 ServiceLocator 已就绪
        protected override void OnPanelOpen()
        {
            _uiManager = GetService<IUIManager>();
            BuildMenu();
        }

        protected override void OnPanelClose() => _uiManager = null;

        /// <summary>默认焦点 / 焦点恢复回到首个按钮。</summary>
        protected override GameObject ResolveFirstSelected()
            => _firstButton != null ? _firstButton.Button.gameObject : null;

        /// <summary>据配置重建按钮列表（public 以便编辑器预览/测试）。</summary>
        public void BuildMenu()
        {
            ClearMenu();
            if (_config == null || _container == null || _buttonPrefab == null) return;

            foreach (var item in _config.Items)
            {
                var view = Instantiate(_buttonPrefab, _container);
                view.gameObject.SetActive(true);
                var captured = item;
                view.Bind(item.labelKey, item.icon, () => Dispatch(captured));
                _buttons.Add(view);
                if (_firstButton == null) _firstButton = view;
            }
        }

        private void ClearMenu()
        {
            _buttons.Clear();
            _firstButton = null;
            if (_container == null) return;
            for (int i = _container.childCount - 1; i >= 0; i--)
            {
                var child = _container.GetChild(i).gameObject;
                if (Application.isPlaying) Destroy(child);
                else DestroyImmediate(child);
            }
        }

        // ── 动作派发 ──────────────────────────────────────────────────────────
        private void Dispatch(PauseMenuConfigSO.Item item)
        {
            switch (item.action)
            {
                case PauseMenuAction.Resume:
                    _onResumeRequested?.Raise();
                    _uiManager?.CloseTopPanel();
                    break;
                case PauseMenuAction.OpenSettings:
                    _uiManager?.OpenPanel(PanelId.Settings);
                    break;
                case PauseMenuAction.ReturnToMainMenu:
                    _uiManager?.CloseTopPanel();
                    _onSceneLoadRequest?.Raise(new SceneLoadRequest
                    {
                        SceneName      = string.IsNullOrEmpty(item.sceneKey) ? AddressKeys.SceneMainMenu : item.sceneKey,
                        TransitionType = TransitionType.Scene,
                    });
                    break;
                case PauseMenuAction.Quit:
                    Application.Quit();
                    break;
                case PauseMenuAction.RaiseEvent:
                    item.eventChannel?.Raise();
                    break;
            }
        }
    }
}