chore: 抢单端UI回退前备份当前完整工作区

Co-authored-by: Cursor <cursoragent@cursor.com>

utils/chat-history.js

@@ -0,0 +1,106 @@
+/**
+ * 聊天历史消息加载（私聊 / 群聊 / 客服共用）
+ * - 排除本地/欢迎语等合成消息的 timestamp，避免下拉加载错位
+ * - 统一 IM 连接等待与 history API 封装
+ */
+
+const SYNTHETIC_MSG_ID = /^(local-|img-|order-|welcome-)/;
+
+export function isHistorySyntheticMessage(msg) {
+  return !!(msg && msg.messageId && SYNTHETIC_MSG_ID.test(String(msg.messageId)));
+}
+
+/** 取当前列表里最早一条「真实」服务端消息的时间戳，供 GoEasy history 分页 */
+export function getOldestHistoryTimestamp(messages, fallback = null) {
+  if (!Array.isArray(messages)) return fallback;
+  let oldest = null;
+  for (const m of messages) {
+    if (!m || m.timestamp == null) continue;
+    if (isHistorySyntheticMessage(m)) continue;
+    if (oldest == null || m.timestamp < oldest) oldest = m.timestamp;
+  }
+  return oldest != null ? oldest : fallback;
+}
+
+export function isImConnected() {
+  const status = wx.goEasy?.getConnectionStatus?.() || 'disconnected';
+  return (status === 'connected' || status === 'reconnected') && !!wx.goEasy?.im;
+}
+
+/** 等待 IM 连接就绪（下拉加载历史前必须先连上） */
+export function waitImConnected(app, timeoutMs = 8000) {
+  return new Promise((resolve) => {
+    if (isImConnected()) {
+      resolve(true);
+      return;
+    }
+    if (app?.ensureConnection) app.ensureConnection();
+    const start = Date.now();
+    const timer = setInterval(() => {
+      if (isImConnected()) {
+        clearInterval(timer);
+        resolve(true);
+      } else if (Date.now() - start >= timeoutMs) {
+        clearInterval(timer);
+        resolve(false);
+      }
+    }, 200);
+  });
+}
+
+export function fetchHistoryMessages({ scene, id, lastTimestamp, limit = 20 }) {
+  return new Promise((resolve, reject) => {
+    if (!wx.goEasy?.im?.history) {
+      reject(new Error('IM未初始化'));
+      return;
+    }
+    if (!id) {
+      reject(new Error('会话ID为空'));
+      return;
+    }
+    wx.goEasy.im.history({
+      type: scene,
+      id: String(id),
+      lastTimestamp: lastTimestamp ?? null,
+      limit,
+      onSuccess: (res) => resolve(res?.content || []),
+      onFailed: (err) => reject(err || new Error('加载历史消息失败')),
+    });
+  });
+}
+
+/**
+ * 合并一页历史消息
+ * @returns {{ messages, hasMore, lastTimestamp }}
+ */
+export function mergeHistoryMessages({ incoming, existing, refresh, limit = 20, mapMessage }) {
+  let list = Array.isArray(incoming) ? [...incoming] : [];
+  list.sort((a, b) => a.timestamp - b.timestamp);
+  if (typeof mapMessage === 'function') {
+    list = list.map((m, idx) => mapMessage(m, idx, list));
+  }
+
+  const prev = Array.isArray(existing) ? existing : [];
+  let final = refresh ? list : [...list, ...prev];
+
+  if (!refresh) {
+    for (let i = 0; i < final.length; i += 1) {
+      if (i === 0) final[i].showTime = true;
+      else final[i].showTime = (final[i].timestamp - final[i - 1].timestamp) / 60000 > 5;
+    }
+  }
+
+  const ids = new Set();
+  const unique = [];
+  for (const m of final) {
+    if (!m?.messageId || ids.has(m.messageId)) continue;
+    ids.add(m.messageId);
+    unique.push(m);
+  }
+
+  return {
+    messages: unique,
+    hasMore: list.length >= limit,
+    lastTimestamp: getOldestHistoryTimestamp(unique, null),
+  };
+}