/*完成SIP协议SUBSCIBE，NOTIFY，INVITE，ACK的逻辑*/

src/main/java/com/inspect/tcpserver/sip/service/SipClientService.java

@@ -20,6 +20,7 @@ import javax.sip.message.MessageFactory;
 import javax.sip.message.Request;
 import javax.sip.message.Response;
 import java.io.BufferedReader;
+import java.io.IOException;
 import java.io.InputStreamReader;
 import java.io.UnsupportedEncodingException;
 import java.net.*;
@@ -777,6 +778,14 @@ public class SipClientService implements SipListener {
                         return;
                     }
 
+                    // 200 OK -> SIP Server
+                    ServerTransaction st = requestEvent.getServerTransaction();
+                    if (st == null) {
+                        st = sipProvider.getNewServerTransaction(request);
+                    }
+                    Response ok = messageFactory.createResponse(Response.OK, request);
+                    st.sendResponse(ok);
+
                     SipXmlEnvelope<?> envelope = SipXmlParser.parse(xml, itemClass);
                     //handleSipEvent(envelope);
                 }
@@ -804,20 +813,29 @@ public class SipClientService implements SipListener {
                 ExpiresHeader expiresHeader = (ExpiresHeader) request.getHeader(ExpiresHeader.NAME);
                 int expires = (expiresHeader != null) ? expiresHeader.getExpires() : 0;
                 log.info("Received SUBSCRIBE expires: {}, XML:\n{}", expires, xml);
+                String eventType = SipXmlParser.peekEventType(xml);
+                log.info("SUBSCRIBE EventType: {}", eventType);
                 ServerTransaction transaction = sipProvider.getNewServerTransaction(request);
+                // 对应协议B.9.1.2 F2 前端系统返回200 OK响应，指示已经接受订阅请求
                 Response response = messageFactory.createResponse(Response.OK, request);
                 response.setExpires(expiresHeader);
                 transaction.sendResponse(response);
 
                 if (expires > 0) {
                     saveSubscription(request, expires);
+                    // 对应协议B.9.1.2 F3 SIP客户端(前端系统)发送没有消息体的NOTIFY给平台，其中Subscription-State头部字段值为active, 指示订阅关系建立。
                     sendInitialNotify(request, transaction, "initial");
                 } else {
                     removeSubscription(request);
                 }
+            } else if (Request.INVITE.equals(request.getMethod())) {
+                handleInvite(requestEvent);
+            } else if(Request.ACK.equals(request.getMethod())) {
+                // RFC 3261: The ACK request does not generate a response.
+                // ACK 是“事务内请求”，不是普通 SIP 方法,不生成任何 Response,ACK 是“事务内请求”，不是普通 SIP 方法
+                startRtspToRtp();
             }
             else {
-
                 Response notImpl = messageFactory.createResponse(Response.NOT_IMPLEMENTED, request);
                 requestEvent.getServerTransaction().sendResponse(notImpl);
                 log.info("Method {} not implemented, replied 501", method);
@@ -833,6 +851,100 @@ public class SipClientService implements SipListener {
         }
     }
 
+    private Process ffmpegProcess;
+
+    private void startRtspToRtp() {
+        try {
+            String cmd =
+                    "ffmpeg -rtsp_transport tcp " +
+                            "-i \"rtsp://admin:wd19216811@192.168.1.244:554/h264/ch1/sub/av_stream\" " +
+                            "-an -vcodec copy " +
+                            "-f rtp -payload_type 96 " +
+                            "\"rtp://192.168.1.116:50000?tcp\"";
+
+            ProcessBuilder pb = new ProcessBuilder(
+                    "bash", "-c", cmd
+            );
+            pb.redirectErrorStream(true);
+
+            ffmpegProcess = pb.start();
+
+            new Thread(() -> {
+                try (BufferedReader br =
+                             new BufferedReader(new InputStreamReader(
+                                     ffmpegProcess.getInputStream()))) {
+                    String line;
+                    while ((line = br.readLine()) != null) {
+                        System.out.println("[FFmpeg] " + line);
+                    }
+                } catch (IOException ignored) {}
+            }).start();
+
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+
+
+    private void handleInvite(RequestEvent requestEvent) throws Exception {
+        Request request = requestEvent.getRequest();
+        log.info("Received INVITE:\n{}", request);
+
+        SipProvider provider = (SipProvider) requestEvent.getSource();
+        ServerTransaction st = requestEvent.getServerTransaction();
+        if (st == null) {
+            st = provider.getNewServerTransaction(request);
+        }
+
+        // ① 100 Trying（非常推荐）
+        Response trying = messageFactory.createResponse(Response.TRYING, request);
+        st.sendResponse(trying);
+
+        // ② 解析对方 SDP（可先只打印）
+        byte[] raw = request.getRawContent();
+        if (raw != null) {
+            String sdp = new String(raw, StandardCharsets.UTF_8);
+            log.info("INVITE SDP:\n{}", sdp);
+        }
+
+        // ③ 构造 200 OK + SDP
+        Response ok = messageFactory.createResponse(Response.OK, request);
+
+        String localSipId = "29001002120107000001";
+        int localRtpPort = 554;
+        // Contact 必须
+        Address contactAddress = addressFactory.createAddress(
+                "sip:" + localSipId + "@" + localIp + ":" + localPort
+        );
+        ContactHeader contactHeader = headerFactory.createContactHeader(contactAddress);
+        ok.addHeader(contactHeader);
+
+        // Content-Type
+        ContentTypeHeader contentType =
+                headerFactory.createContentTypeHeader("application", "sdp");
+
+        // 返回 SDP（示例）
+        String sdp =
+                "v=0\r\n" +
+                        "o=" + localSipId + " 0 0 IN IP4 " + localIp + "\r\n" +
+                        "s=Play\r\n" +
+                        "c=IN IP4 " + localIp + "\r\n" +
+                        "t=0 0\r\n" +
+                        "m=video " + localRtpPort + " TCP/RTP/AVP 96\r\n" +
+                        "a=sendonly\r\n" +
+                        "a=setup:active\r\n" +
+                        "a=connection:new\r\n" +
+                        "a=rtpmap:96 PS/90000\r\n";
+
+        ok.setContent(sdp, contentType);
+
+        // ④ 发送 200 OK
+        st.sendResponse(ok);
+
+        log.info("INVITE handled: 200 OK sent");
+    }
+
+
     @Override
     public void processTimeout(TimeoutEvent timeoutEvent) {
         log.warn("SIP timeout: {}", timeoutEvent);
@@ -977,12 +1089,12 @@ public class SipClientService implements SipListener {
             notifyRequest.addHeader(ssHeader);
 
             // 消息体
-            String xmlBody = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
-                    "<SIP_XML>\n" +
-                    "    <Type>" + bodyText + "</Type>\n" +
-                    "</SIP_XML>";
-            ContentTypeHeader contentTypeHeader = headerFactory.createContentTypeHeader("application", "xml");
-            notifyRequest.setContent(xmlBody, contentTypeHeader);
+//            String xmlBody = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n" +
+//                    "<SIP_XML>\n" +
+//                    "    <Type>" + bodyText + "</Type>\n" +
+//                    "</SIP_XML>";
+//            ContentTypeHeader contentTypeHeader = headerFactory.createContentTypeHeader("application", "xml");
+//            notifyRequest.setContent(xmlBody, contentTypeHeader);
 
             // 发送
             ClientTransaction ct = sipProvider.getNewClientTransaction(notifyRequest);
@@ -995,6 +1107,54 @@ public class SipClientService implements SipListener {
         }
     }
 
+    private void sendSubscribeNotifyToSipServer(Request subscribeRequest) {
+        try {
+            // 获取必要头字段
+            CallIdHeader callIdHeader = (CallIdHeader) subscribeRequest.getHeader(CallIdHeader.NAME);
+            CSeqHeader cseqHeader = (CSeqHeader) subscribeRequest.getHeader(CSeqHeader.NAME);
+            FromHeader fromHeader = (FromHeader) subscribeRequest.getHeader(FromHeader.NAME);
+            ToHeader toHeader = (ToHeader) subscribeRequest.getHeader(ToHeader.NAME);
+            EventHeader eventHeader = (EventHeader) subscribeRequest.getHeader(EventHeader.NAME);
+            ContactHeader contactHeader = (ContactHeader) subscribeRequest.getHeader(ContactHeader.NAME);
+
+            List<ViaHeader> viaHeaders = new ArrayList<>();
+            ViaHeader viaHeader = headerFactory.createViaHeader(localIp, localPort, transport.toUpperCase(), null);
+            viaHeaders.add(viaHeader);
+            // 创建 NOTIFY 请求
+            Request notifyRequest = messageFactory.createRequest(
+                    subscribeRequest.getRequestURI(),
+                    Request.NOTIFY,
+                    callIdHeader,
+                    headerFactory.createCSeqHeader(cseqHeader.getSeqNumber() + 1, Request.NOTIFY),
+                    fromHeader,
+                    toHeader,
+                    viaHeaders,
+                    headerFactory.createMaxForwardsHeader(70)
+            );
+
+            // 加入 Contact
+            notifyRequest.addHeader(contactHeader);
+
+            // 必须的事件头
+            notifyRequest.addHeader(eventHeader);
+
+            // Subscription-State 头
+            SubscriptionStateHeader ssHeader = headerFactory.createSubscriptionStateHeader("active");
+            ssHeader.setExpires(3600);
+            notifyRequest.addHeader(ssHeader);
+
+            ContentTypeHeader contentTypeHeader = headerFactory.createContentTypeHeader("application", "xml");
+            notifyRequest.setContent(null, contentTypeHeader);
+
+            // 发送
+            ClientTransaction ct = sipProvider.getNewClientTransaction(notifyRequest);
+            ct.sendRequest();
+            log.info("sendSubscribeNotifyToSipServer: callId: {}", callIdHeader.getCallId());
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+
 
     private void removeSubscription(Request request) {
         CallIdHeader callIdHeader = (CallIdHeader) request.getHeader(CallIdHeader.NAME);