feat: DBNMQTTool 日志增强 — 收发打印 topic + payload 详情

新增 _log_send() / _log_recv() 两个统一日志方法:
- 发送: 标签 + → topic + PASTE:{精简payload}
- 接收: ← topic + summary + RECV:{精简payload}
- payload >200/300 字符自动截断

覆盖所有收发路径:
- [模拟]/[协议]/[自定义]/[命令] 发送
- 响应/loop_data/event_report/heartbeat/Initialize 接收
- mqtt_client.py 自动订阅事件日志

DBNMQTTool/main.py

@@ -450,7 +450,7 @@ class MainWindow(QMainWindow):
         try:
             payload = json.loads(text)
             self._mqtt.publish(topic, payload, qos=1)
-            self._log(f"[模拟] → {topic}")
+            self._log_send("[模拟]", topic, payload)
         except json.JSONDecodeError as e:
             QMessageBox.warning(self, "JSON 错误", str(e))
         except Exception as e:
@@ -585,7 +585,7 @@ class MainWindow(QMainWindow):
             else:
                 payload = build_request(CMD_DEV_INFO_QUERY)
             self._mqtt.publish(topic, payload)
-            self._log(f"[协议] → {topic}")
+            self._log_send("[协议]", topic, payload)
         except json.JSONDecodeError as e:
             QMessageBox.warning(self, "JSON 错误", str(e))
         except Exception as e:
@@ -687,7 +687,7 @@ class MainWindow(QMainWindow):
             payload = json.loads(raw) if raw else {}
             qos = int(self._custom_qos.currentText())
             self._mqtt.publish(topic, payload, qos=qos)
-            self._log(f"[自定义] → {topic}")
+            self._log_send("[自定义]", topic, payload)
         except json.JSONDecodeError as e:
             QMessageBox.warning(self, "JSON 错误", str(e))
         except Exception as e:
@@ -775,7 +775,7 @@ class MainWindow(QMainWindow):
             code = payload.get("code", -1)
             pmsg = payload.get("msg", "")
             data = payload.get("data", {})
-            self._log(f"[{ts}] {dev_serial} ← {cmd}  code={code} {pmsg}")
+            self._log_recv(topic, payload, f"{cmd} code={code} {pmsg}")
             if code == 0:
                 if cmd == CMD_DEV_INFO_QUERY:
                     self._devmgr.update_from_dev_info(dev_serial, data)
@@ -789,20 +789,27 @@ class MainWindow(QMainWindow):
             data = payload.get("data", {})
             self._devmgr.update_loop_data(dev_serial, data)
             chs = len(data.get("channels", []))
-            self._log(f"[{ts}] {dev_serial} ← loop_data ({chs} 通道)")
+            self._log_recv(topic, payload, f"loop_data ({chs}ch)")
             self._append_text(self._loop_text, json.dumps(payload, indent=2, ensure_ascii=False))
 
         elif cmd == CMD_EVENT_REPORT:
             data = payload.get("data", {})
             self._devmgr.update_event(dev_serial, data)
             evt_count = len(data.get("events", []))
-            self._log(f"[{ts}] {dev_serial} ← event_report ({evt_count} 事件)")
+            self._log_recv(topic, payload, f"event ({evt_count} events)")
             self._append_text(self._event_text, json.dumps(payload, indent=2, ensure_ascii=False))
 
         elif cmd == CMD_HEARTBEAT:
             data = payload.get("data", {})
             self._devmgr.update_heartbeat(dev_serial, data)
-            self._log(f"[{ts}] {dev_serial} ← heartbeat (uptime={data.get('uptime', 0)}s)")
+            self._log_recv(topic, payload, f"heartbeat uptime={data.get('uptime', 0)}s")
+
+        # 旧协议 / 无 cmd 字段 的消息（如 Initialize）
+        elif "Method" in payload:
+            self._log_recv(topic, payload, f"Method={payload.get('Method', '?')}")
+
+        else:
+            self._log_recv(topic, payload)
 
         # 自定义订阅消息 → 显示到自定义 Topic 接收区
         for sub_topic in self._custom_subs:
@@ -840,7 +847,10 @@ class MainWindow(QMainWindow):
             return
         try:
             mid = self._mqtt.send_command(sn, cmd, data)
-            self._log(f"→ {sn} {cmd} (msg_id={mid})")
+            from dbn_mqtt_tool.protocol import build_request, get_topic_for_cmd
+            msg = build_request(cmd, data)
+            topic = get_topic_for_cmd(cmd, sn)
+            self._log_send(f"[命令] {sn}", topic, msg)
         except Exception as e:
             QMessageBox.critical(self, "发送失败", str(e))
 
@@ -979,6 +989,24 @@ class MainWindow(QMainWindow):
         self._log_text.append(f"[{ts}] {msg}")
         self._log_text.moveCursor(QTextCursor.End)
 
+    # ---- 详细收发日志 ----
+
+    def _log_send(self, label: str, topic: str, payload: dict):
+        """记录发送消息: 标签 + topic + 精简 payload"""
+        payload_str = json.dumps(payload, ensure_ascii=False)
+        if len(payload_str) > 200:
+            payload_str = payload_str[:200] + "..."
+        self._log(f"{label} → {topic}")
+        self._log(f"       PASTE: {payload_str}")
+
+    def _log_recv(self, topic: str, payload: dict, summary: str = ""):
+        """记录接收消息: topic + summary + 精简 payload"""
+        payload_str = json.dumps(payload, ensure_ascii=False)
+        if len(payload_str) > 300:
+            payload_str = payload_str[:300] + "..."
+        self._log(f"← {topic}{' ' + summary if summary else ''}")
+        self._log(f"       RECV: {payload_str}")
+
 
 def main():
     app = QApplication(sys.argv)