test/Assets/PerfectWorld/Scripts/Chat/UI/ChatPanelUI.cs

using System;
using System.Collections.Generic;
using CSNetwork;
using CSNetwork.GPDataType;
using UnityEngine;
using UnityEngine.Pool;
using UnityEngine.UI;

namespace BrewMonster.Scripts.ChatUI
{
    [Serializable]
    public struct ChatMessageData
    {
        public string message;
        public byte channel;
    }

    public class ChatPanelUI : MonoBehaviour
    {
        [Header("UI")] public ScrollRect scrollRect;
        public GameObject chatPanelUIGO;
        public RectTransform content;
        public ChatMessageView messagePrefab;
        //public GameObject newMessageIndicator;

        [Header("Config")] public int maxVisibleMessages = 30;
        public int maxStoredMessages = 2000;

        [Header("Chat System Data")]
        public ChatSystemSO chatSystemSO;
        private Dictionary<byte, Sprite> _iconCache;

        private List<ChatMessageData> _messages = new();
        private List<ChatMessageView> _visibleViews = new();
        private List<ChatMessageData> _filteredMessagesCache = new();

        private ObjectPool<ChatMessageView> _pool;

        private bool _userAtBottom = true;
        private ChatChannel _currentFilterChannel = ChatChannel.GP_CHAT_LOCAL;

        void Awake()
        {
            ClearChat();
            _iconCache = new Dictionary<byte, Sprite>();
            if (chatSystemSO != null && chatSystemSO.channelIcons != null)
            {
                foreach (var mapping in chatSystemSO.channelIcons)
                {
                    _iconCache[(byte)mapping.channel] = mapping.icon;
                }
            }

            EventBus.Subscribe<OnEventClearChat>(OnChatMessageClear);
            EventBus.Subscribe<GameSession.ChatMessageEvent>(OnChatMessageReceived);
            EventBus.Subscribe<ChatChannelFilterChangedEvent>(OnChannelFilterChanged);
            _pool = new ObjectPool<ChatMessageView>(
                CreateItem,
                OnGetItem,
                OnReleaseItem,
                OnDestroyItem,
                false,
                10,
                100
            );

            scrollRect.onValueChanged.AddListener(OnScrollChanged);
        }

        private void OnDestroy()
        {
            EventBus.Unsubscribe<OnEventClearChat>(OnChatMessageClear);
            EventBus.Unsubscribe<GameSession.ChatMessageEvent>(OnChatMessageReceived);
            EventBus.Unsubscribe<ChatChannelFilterChangedEvent>(OnChannelFilterChanged);
            
            if (_pool != null)
            {
                _pool.Clear();
                _pool.Dispose();
            }
        }

        private void OnChannelFilterChanged(ChatChannelFilterChangedEvent e)
        {
            if (this == null) return;
            _currentFilterChannel = e.channel;
            if (chatPanelUIGO != null && chatPanelUIGO.activeSelf)
            {
                RefreshVisible();
            }
        }

        private bool ShouldShowMessage(ChatMessageData data)
        {
            if (_currentFilterChannel == ChatChannel.GP_CHAT_LOCAL) return true;
            if (data.channel == (byte)ChatChannel.GP_CHAT_MISC) return true;
            return data.channel == (byte)_currentFilterChannel;
        }

        private void OnChatMessageReceived(GameSession.ChatMessageEvent x)
        {
            ChatThreadDispatcher.Instance.Post(() =>
            {
                if (this == null) return;
                AddMessage(x.context, x.channel);
            });
        }


        private void OnChatMessageClear(OnEventClearChat obj)
        {
            ChatThreadDispatcher.Instance.Post(() =>
            {
                if (this == null) return;
                ClearChat();
            });
        }

        ChatMessageView CreateItem()
        {
            if (messagePrefab == null || content == null) return null;
            var item = Instantiate(messagePrefab);
            item.transform.SetParent(content, false);
            return item;
        }

        void OnGetItem(ChatMessageView item)
        {
            if (item != null)
                item.gameObject.SetActive(true);
        }

        void OnReleaseItem(ChatMessageView item)
        {
            if (item != null)
                item.gameObject.SetActive(false);
        }

        void OnDestroyItem(ChatMessageView item)
        {
            if (item != null)
                Destroy(item.gameObject);
        }

        void OnScrollChanged(Vector2 pos)
        {
            _userAtBottom = scrollRect.verticalNormalizedPosition <= 0.001f;

            if (_userAtBottom)
            {
                //newMessageIndicator.SetActive(false);
            }
        }

        bool IsAtBottom()
        {
            return scrollRect.verticalNormalizedPosition <= 0.001f;
        }

        public void AddMessage(string msg, byte channel)
        {
            if (this == null || chatPanelUIGO == null) return;

            var data = new ChatMessageData { message = msg, channel = channel };
            _messages.Add(data);

            if (_messages.Count > maxStoredMessages)
                _messages.RemoveAt(0);

            if (!chatPanelUIGO.activeSelf)
                return;

            if (ShouldShowMessage(data))
            {
                AddMessageView(data);

                if (_userAtBottom)
                    ScrollToBottom();
            }
        }

        void AddMessageView(ChatMessageData data)
        {
            if (this == null) return;
            var view = _pool.Get();
            if (view == null) view = CreateItem();
            if (view == null) return;
            
            view.transform.SetParent(content, false);
            view.transform.SetAsLastSibling();

            Sprite icon = _iconCache.ContainsKey(data.channel) ? _iconCache[data.channel] : null;
            view.Bind(icon, data.message);

            _visibleViews.Add(view);

            if (_visibleViews.Count > maxVisibleMessages)
            {
                var old = _visibleViews[0];
                _visibleViews.RemoveAt(0);
                if (old != null)
                {
                    _pool.Release(old);
                }
            }

            Canvas.ForceUpdateCanvases();
        }

        void RefreshVisible()
        {
            foreach (var view in _visibleViews)
            {
                if (view != null) 
                    _pool.Release(view);
            }

            _visibleViews.Clear();

            _filteredMessagesCache.Clear();
            foreach (var msg in _messages)
            {
                if (ShouldShowMessage(msg))
                {
                    _filteredMessagesCache.Add(msg);
                }
            }

            int start = Mathf.Max(0, _filteredMessagesCache.Count - maxVisibleMessages);

            for (int i = start; i < _filteredMessagesCache.Count; i++)
            {
                var view = _pool.Get();
                if (view == null) view = CreateItem();
                if (view == null) continue;
                
                view.transform.SetParent(content, false);
                view.transform.SetAsLastSibling();

                var data = _filteredMessagesCache[i];
                Sprite icon = _iconCache.ContainsKey(data.channel) ? _iconCache[data.channel] : null;
                view.Bind(icon, data.message);

                _visibleViews.Add(view);
            }

            Canvas.ForceUpdateCanvases();
            ScrollToBottom();
        }

        public void ScrollToBottom()
        {
            Canvas.ForceUpdateCanvases();
            scrollRect.verticalNormalizedPosition = 0f;
            //newMessageIndicator.SetActive(false);
        }

        public void ClearChat()
        {
            foreach (var view in _visibleViews)
            {
                if (view != null)
                    _pool.Release(view);
            }

            _visibleViews.Clear();
            _messages.Clear();
        }

        public void OnHandlerChatButton()
        {
            bool open = !chatPanelUIGO.activeSelf;
            chatPanelUIGO.SetActive(open);

            if (open)
                RefreshVisible();
        }
    }

    public struct OnEventClearChat{}
}