修复：后台恢复时只省略过时的系统/游戏通知，保留用户聊天记录

resources/js/chat-room/message-renderer.js

@@ -457,8 +457,22 @@ export function enqueueChatMessage(msg) {
     state.chatMessageFlushTimer = scheduleFlush(flushQueuedChatMessages);
 }
 
-/** 后台恢复时公屏最大渲染条数，避免暴刷 */
-const MAX_BURST_RENDER = 50;
+/**
+ * 判断是否为普通用户聊天消息（非系统/游戏通知）。
+ */
+function isUserChatMessage(msg) {
+    if (!msg || !msg.from_user) return false;
+    const u = msg.from_user;
+    if (SYSTEM_USERS.includes(u)) return false;
+    if (u.endsWith("播报")) return false;
+    if (u === "百家乐" || u === "跑马") return false;
+    return true;
+}
+
+/** 后台恢复时系统通知最多保留条数 */
+const MAX_SYSTEM_BURST = 20;
+/** 后台恢复时超过该时间的系统通知直接丢弃（分钟） */
+const MAX_SYSTEM_AGE_MINUTES = 10;
 
 /**
  * 分批渲染待处理消息，给动画、输入和滚动留出主线程时间。
@@ -469,21 +483,53 @@ export function flushQueuedChatMessages() {
 
     state.chatMessageFlushTimer = null;
 
-    // 大批量消息堆积（后台标签页恢复）时，丢弃早于 MAX_BURST_RENDER 的消息，
-    // 插入一条省略提示，避免用户一回来就看到满屏消息狂刷。
-    if (state.pendingChatMessages.length > MAX_BURST_RENDER + 20) {
-        const skipped = state.pendingChatMessages.length - MAX_BURST_RENDER;
-        state.pendingChatMessages.splice(0, skipped);
+    // 大批量消息堆积（后台标签页恢复）时，保留所有用户聊天记录，
+    // 但过时的系统/游戏通知只保留最近 MAX_SYSTEM_BURST 条。
+    if (state.pendingChatMessages.length > MAX_SYSTEM_BURST + 30) {
+        const now = Date.now();
+        const maxAge = MAX_SYSTEM_AGE_MINUTES * 60 * 1000;
+        const totalSystem = state.pendingChatMessages.filter((m) => !isUserChatMessage(m)).length;
+        let systemSeen = 0;
+        let dropped = 0;
 
-        const container = state.container;
-        if (container) {
-            const notice = document.createElement("div");
-            notice.className = "msg-line msg-burst-notice";
-            notice.style.cssText =
-                "text-align:center;padding:6px 0;margin:4px 0;font-size:12px;color:#94a3b8;border-top:1px dashed #d1d5db;border-bottom:1px dashed #d1d5db;";
-            notice.textContent = `⏫ 省略了 ${skipped} 条未读消息`;
-            container.appendChild(notice);
+        const filtered = state.pendingChatMessages.filter((msg) => {
+            if (isUserChatMessage(msg)) return true;
+
+            systemSeen++;
+
+            // 超过10分钟的系统通知直接丢弃
+            let msgTime = 0;
+            if (msg.sent_at) {
+                msgTime = new Date(msg.sent_at.replace(" ", "T")).getTime();
+            }
+            if (msgTime > 0 && now - msgTime > maxAge) {
+                dropped++;
+                return false;
+            }
+
+            // 从旧到新遍历，只保留最后 MAX_SYSTEM_BURST 条系统通知
+            const remainingAfter = totalSystem - systemSeen;
+            if (remainingAfter >= MAX_SYSTEM_BURST) {
+                dropped++;
+                return false;
+            }
+
+            return true;
+        });
+
+        if (dropped > 0) {
+            const container = state.container;
+            if (container) {
+                const notice = document.createElement("div");
+                notice.className = "msg-line msg-burst-notice";
+                notice.style.cssText =
+                    "text-align:center;padding:6px 0;margin:4px 0;font-size:12px;color:#94a3b8;border-top:1px dashed #d1d5db;border-bottom:1px dashed #d1d5db;";
+                notice.textContent = `⏫ 省略了 ${dropped} 条系统通知`;
+                container.appendChild(notice);
+            }
         }
+
+        state.pendingChatMessages = filtered;
     }
 
     const batch = state.pendingChatMessages.splice(0, CHAT_MESSAGE_FLUSH_BATCH_SIZE);