优化聊天室首屏和在线名单性能

resources/views/chat/partials/scripts.blade.php

@@ -73,6 +73,7 @@
     let onlineUsers = {};
     let autoScroll = true;
     let userBadgeRotationTick = 0;
+    let userListRenderTimer = null;
     let _maxMsgId = 0; // 记录当前收到的最大消息 ID
     const initialChatPreferences = normalizeChatPreferences(window.chatContext?.chatPreferences || {});
     let blockedSystemSenders = new Set(initialChatPreferences.blocked_system_senders);
@@ -1907,7 +1908,7 @@
      */
     function _renderUserListToContainer(targetContainer, sortBy, keyword) {
         if (!targetContainer) return;
-        targetContainer.innerHTML = '';
+        const fragment = document.createDocumentFragment();
 
         // 在列表顶部添加"大家"条目（原版风格）
         let allDiv = document.createElement('div');
@@ -1916,7 +1917,7 @@
         allDiv.onclick = () => {
             toUserSelect.value = '大家';
         };
-        targetContainer.appendChild(allDiv);
+        fragment.appendChild(allDiv);
 
         // ── AI 小助手（已在 onlineUsers 中动态维护，移除硬编码）──
 
@@ -1994,15 +1995,24 @@
                     _tapTime = now;
                 }
             }, { passive: false });
-            targetContainer.appendChild(item);
+            fragment.appendChild(item);
         });
 
+        targetContainer.replaceChildren(fragment);
         refreshRenderedUserBadges(targetContainer);
     }
 
     function renderUserList() {
-        userList.innerHTML = '';
-        toUserSelect.innerHTML = '<option value="大家">大家</option>';
+        if (userListRenderTimer) {
+            window.clearTimeout(userListRenderTimer);
+            userListRenderTimer = null;
+        }
+
+        const selectFragment = document.createDocumentFragment();
+        const everyoneOption = document.createElement('option');
+        everyoneOption.value = '大家';
+        everyoneOption.textContent = '大家';
+        selectFragment.appendChild(everyoneOption);
 
         // 获取排序方式和搜索词
         const sortSelect = document.getElementById('user-sort-select');
@@ -2023,9 +2033,10 @@
                     text = '🤖 AI小班长';
                 }
                 option.textContent = text;
-                toUserSelect.appendChild(option);
+                selectFragment.appendChild(option);
             }
         }
+        toUserSelect.replaceChildren(selectFragment);
 
         const count = Object.keys(onlineUsers).length;
         onlineCount.innerText = count;
@@ -2039,6 +2050,22 @@
         window.dispatchEvent(new Event('chatroom:users-updated'));
     }
 
+    /**
+     * 合并高频在线名单变动，避免 Presence 连续进出时重复重建名单 DOM。
+     *
+     * @param {number} delay 等待毫秒数
+     */
+    function scheduleRenderUserList(delay = 120) {
+        if (userListRenderTimer) {
+            window.clearTimeout(userListRenderTimer);
+        }
+
+        userListRenderTimer = window.setTimeout(() => {
+            userListRenderTimer = null;
+            renderUserList();
+        }, delay);
+    }
+
     /**
      * 获取用户当前仍然有效的当日状态。
      *
@@ -2581,7 +2608,7 @@
 
         setOnlineUserDailyStatus(window.chatContext.username, getCurrentUserDailyStatus());
         syncDailyStatusUi();
-        renderUserList();
+        scheduleRenderUserList(0);
     });
 
     // 监听机器人动态开关
@@ -2596,7 +2623,7 @@
             delete onlineUsers['AI小班长'];
             window.chatContext.botUser = null;
         }
-        renderUserList();
+        scheduleRenderUserList();
     });
 
     window.addEventListener('chat:user-status-updated', (e) => {
@@ -2614,19 +2641,19 @@
             syncDailyStatusUi();
         }
 
-        renderUserList();
+        scheduleRenderUserList();
     });
 
     window.addEventListener('chat:joining', (e) => {
         const user = e.detail;
         hydrateOnlineUserPayload(user.username, user);
-        renderUserList();
+        scheduleRenderUserList();
     });
 
     window.addEventListener('chat:leaving', (e) => {
         const user = e.detail;
         delete onlineUsers[user.username];
-        renderUserList();
+        scheduleRenderUserList();
     });
 
     window.addEventListener('chat:message', (e) => {