From 2db9c0154ee7e1e0c35bd2e3c05a4c76d71c7b09 Mon Sep 17 00:00:00 2001
From: sh123 <sh123@users.noreply.github.com>
Date: Sat, 1 Jul 2023 12:25:13 +0300
Subject: [PATCH] Handle third party header with rx gating

---
 codec2talkie/build.gradle                     |  4 ++--
 .../radio/codec2talkie/protocol/AprsIs.java   |  5 +++++
 .../protocol/aprs/tools/AprsIsData.java       | 20 +++++++++++++++++--
 3 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/codec2talkie/build.gradle b/codec2talkie/build.gradle
index 79b33e0..c5c81ee 100644
--- a/codec2talkie/build.gradle
+++ b/codec2talkie/build.gradle
@@ -10,8 +10,8 @@ android {
         applicationId "com.radio.codec2talkie"
         minSdkVersion 23
         targetSdkVersion 30
-        versionCode 160
-        versionName "1.60"
+        versionCode 161
+        versionName "1.61"
 
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
     }
diff --git a/codec2talkie/src/main/java/com/radio/codec2talkie/protocol/AprsIs.java b/codec2talkie/src/main/java/com/radio/codec2talkie/protocol/AprsIs.java
index 61c5368..9bd38ac 100644
--- a/codec2talkie/src/main/java/com/radio/codec2talkie/protocol/AprsIs.java
+++ b/codec2talkie/src/main/java/com/radio/codec2talkie/protocol/AprsIs.java
@@ -171,9 +171,14 @@ public class AprsIs implements Protocol, Runnable {
         @Override
         protected void onReceiveData(String src, String dst, String path, byte[] data) {
             if (_isRxGateEnabled && !_isLoopbackTransport) {
+                // NOTE, https://aprs-is.net/IGateDetails.aspx
                 AprsIsData aprsIsData = new AprsIsData(src, dst, path, new String(data));
                 if (aprsIsData.isEligibleForRxGate()) {
                     synchronized (_toAprsIsQueue) {
+                        // strip "rf header" for third party packets before gating
+                        if (aprsIsData.hasThirdParty()) {
+                            aprsIsData = aprsIsData.thirdParty;
+                        }
                         String rawData = aprsIsData.toString() + "\n";
                         _toAprsIsQueue.put(rawData.getBytes());
                     }
diff --git a/codec2talkie/src/main/java/com/radio/codec2talkie/protocol/aprs/tools/AprsIsData.java b/codec2talkie/src/main/java/com/radio/codec2talkie/protocol/aprs/tools/AprsIsData.java
index c7e58f3..e6f6f78 100644
--- a/codec2talkie/src/main/java/com/radio/codec2talkie/protocol/aprs/tools/AprsIsData.java
+++ b/codec2talkie/src/main/java/com/radio/codec2talkie/protocol/aprs/tools/AprsIsData.java
@@ -11,6 +11,7 @@ public class AprsIsData {
     public String digipath;
     public String rawDigipath;
     public String data;
+    public AprsIsData thirdParty;
 
     public AprsIsData() {
     }
@@ -20,6 +21,14 @@ public class AprsIsData {
         this.dst = dst;
         this.digipath = path;
         this.data = data;
+        // handle third party packet
+        if (data.length() > 10 && data.startsWith("}")) {
+            thirdParty = AprsIsData.fromString(data.substring(1));
+        }
+    }
+
+    public boolean hasThirdParty() {
+        return thirdParty != null;
     }
 
     @NonNull
@@ -39,8 +48,12 @@ public class AprsIsData {
                 rawDigipath.contains("NOGATE") ||
                 rawDigipath.contains("RFONLY");
 
-        // do not gate TCPIP/NOGATE and queries
-        return !hasNoGate && !data.startsWith("?");
+        boolean thirdPartyHasNoGate = thirdParty != null &&
+                (thirdParty.rawDigipath.contains("TCPIP") ||
+                        thirdParty.rawDigipath.contains("TCPXX"));
+
+        // do not gate TCPIP/NOGATE, queries and third party tcp ip packets
+        return !hasNoGate && !data.startsWith("?") && !thirdPartyHasNoGate;
     }
 
     public boolean isEligibleForTxGate() {
@@ -65,6 +78,9 @@ public class AprsIsData {
         aprsIsData.digipath = joinTail(path, ",", "^WIDE.+$");
         aprsIsData.rawDigipath = joinTail(path, ",", ".*");
         aprsIsData.data = joinTail(digipathData, ":", ".*");
+        if (aprsIsData.data.length() > 10 && aprsIsData.data.startsWith("}")) {
+            aprsIsData.thirdParty = AprsIsData.fromString(aprsIsData.data.substring(1));
+        }
         return aprsIsData;
     }