zeling_v2/Assets/_Game/Scripts/UI/Controls/UITabGroup.cs

using System;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;
using BaseGames.Core.Events;

namespace BaseGames.UI
{
    /// <summary>
    /// 可复用标签组（从 <see cref="BaseGames.UI.Inventory.InventoryHubPanel"/> 的 Tab 逻辑提取）。
    ///
    /// 职责：管理一组 Tab（内容根 + 头部按钮 + 高亮），处理 Next/Prev/Select 切换、
    /// 头部高亮、焦点委托（内容若实现 <see cref="IFocusable"/> 则接管，否则聚焦头部按钮），
    /// 可选跨重建记忆当前 Tab，并通过 C# 事件 + 可选 SO 频道广播索引。
    ///
    /// 解耦：不引用任何具体 Tab 类型，只持有 Tab 根 <see cref="GameObject"/>。
    /// 由宿主面板在 OnEnable 中调用 <see cref="Activate"/>，并把肩键频道接到 <see cref="Next"/>/<see cref="Prev"/>。
    /// </summary>
    public class UITabGroup : MonoBehaviour
    {
        [Serializable]
        public struct Tab
        {
            [Tooltip("Tab 内容根节点（激活时 SetActive(true)）。")]
            public GameObject content;
            [Tooltip("Tab 头部按钮（点击跳转；高亮显示当前选中）。可空。")]
            public Button headerButton;
            [Tooltip("Tab 头部高亮节点（选中时 SetActive(true)）。可空。")]
            public GameObject headerHighlight;
        }

        [Header("Tabs（按显示顺序）")]
        [SerializeField] private Tab[] _tabs;

        [Tooltip("默认打开的 Tab 索引。")]
        [SerializeField] private int _defaultIndex = 0;

        [Tooltip("是否记住上次停留的 Tab（跨面板重开）。")]
        [SerializeField] private bool _rememberLast = true;

        [Tooltip("跨重建记忆用的键；为空则只在本实例存活期间记忆。")]
        [SerializeField] private string _persistKey = "";

        [Header("Event Channels（可选）")]
        [Tooltip("当前 Tab 变化时广播索引。可空。")]
        [SerializeField] private IntEventChannelSO _onTabChanged;

        /// <summary>当前 Tab 变化时触发（参数为新索引）。</summary>
        public event Action<int> TabChanged;

        public int CurrentIndex { get; private set; } = -1;
        public int TabCount => _tabs?.Length ?? 0;

        // 跨重建记忆（静态：面板/组件被销毁重建后仍保留）
        private static readonly Dictionary<string, int> s_persist = new();

        private bool _wired;

        private void Awake() => EnsureWired();

        private void EnsureWired()
        {
            if (_wired || _tabs == null) return;
            for (int i = 0; i < _tabs.Length; i++)
            {
                int captured = i;
                if (_tabs[i].headerButton != null)
                {
                    _tabs[i].headerButton.onClick.RemoveAllListeners();
                    _tabs[i].headerButton.onClick.AddListener(() => Select(captured));
                }
                if (_tabs[i].content != null) _tabs[i].content.SetActive(false);
                if (_tabs[i].headerHighlight != null) _tabs[i].headerHighlight.SetActive(false);
            }
            _wired = true;
        }

        /// <summary>激活标签组并打开起始 Tab（默认或记忆）。宿主面板在 OnEnable 中调用。</summary>
        public void Activate()
        {
            EnsureWired();
            if (TabCount == 0) return;
            int start = _rememberLast && TryGetPersisted(out var p) ? p : _defaultIndex;
            CurrentIndex = -1;                  // 强制 Select 执行切换
            Select(Mathf.Clamp(start, 0, TabCount - 1));
        }

        public void Next() => Step(+1);
        public void Prev() => Step(-1);

        private void Step(int dir)
        {
            if (TabCount == 0) return;
            int next = CurrentIndex;
            for (int i = 0; i < _tabs.Length; i++)   // 跳过未配置 content 的空槽
            {
                next = (next + dir + _tabs.Length) % _tabs.Length;
                if (_tabs[next].content != null) break;
            }
            Select(next);
        }

        /// <summary>切换到指定 Tab；无效或与当前相同则忽略。</summary>
        public void Select(int index)
        {
            EnsureWired();
            if (TabCount == 0) return;
            index = Mathf.Clamp(index, 0, _tabs.Length - 1);
            if (index == CurrentIndex) return;

            // 关闭旧 Tab
            if (CurrentIndex >= 0 && CurrentIndex < _tabs.Length)
            {
                if (_tabs[CurrentIndex].content != null) _tabs[CurrentIndex].content.SetActive(false);
                if (_tabs[CurrentIndex].headerHighlight != null) _tabs[CurrentIndex].headerHighlight.SetActive(false);
            }

            CurrentIndex = index;
            SetPersisted(index);

            // 打开新 Tab
            var tab = _tabs[index];
            if (tab.content != null) tab.content.SetActive(true);
            if (tab.headerHighlight != null) tab.headerHighlight.SetActive(true);

            FocusCurrent();
            _onTabChanged?.Raise(index);
            TabChanged?.Invoke(index);
        }

        /// <summary>把焦点交给当前 Tab（内容 IFocusable 优先，否则其头部按钮）。供宿主 OnFocusRestored 调用。</summary>
        public void FocusCurrent()
        {
            if (CurrentIndex < 0 || CurrentIndex >= TabCount) return;
            var tab = _tabs[CurrentIndex];
            var focusable = tab.content != null ? tab.content.GetComponent<IFocusable>() : null;
            if (focusable != null) focusable.OnFocusRestored();
            else if (tab.headerButton != null && EventSystem.current != null)
                EventSystem.current.SetSelectedGameObject(tab.headerButton.gameObject);
        }

        // ── 记忆 ──────────────────────────────────────────────────────────────
        private bool TryGetPersisted(out int index)
        {
            if (!string.IsNullOrEmpty(_persistKey) && s_persist.TryGetValue(_persistKey, out index)) return true;
            if (CurrentIndex >= 0) { index = CurrentIndex; return true; }
            index = -1;
            return false;
        }

        private void SetPersisted(int index)
        {
            if (!string.IsNullOrEmpty(_persistKey)) s_persist[_persistKey] = index;
        }
    }
}