From 6d421ee0b3f0dab5d1a6a067125d65f2c83b4c3d Mon Sep 17 00:00:00 2001
From: Scott Bender <scott@scottbender.net>
Date: Thu, 21 Nov 2024 12:00:53 -0500
Subject: [PATCH] fix: ignore static AIS data for self if configured in sk

---
 packages/streams/n2k-signalk.js | 21 +++++++++++++++++++++
 1 file changed, 21 insertions(+)

diff --git a/packages/streams/n2k-signalk.js b/packages/streams/n2k-signalk.js
index 6a209df8e..9e4d89d47 100644
--- a/packages/streams/n2k-signalk.js
+++ b/packages/streams/n2k-signalk.js
@@ -20,6 +20,8 @@ const N2kMapper = require('@signalk/n2k-signalk').N2kMapper
 
 require('util').inherits(ToSignalK, Transform)
 
+const aisPGNs = [129794, 129810, 129040, 130842, 129809]
+
 function ToSignalK(options) {
   Transform.call(this, {
     objectMode: true,
@@ -108,6 +110,15 @@ ToSignalK.prototype.isFiltered = function (source) {
   )
 }
 
+ToSignalK.prototype.filterSelfAISStatic = function (values) {
+  return values.filter((kv) => {
+    return (
+      kv.path !== '' &&
+      this.app.config.baseDeltaEditor.getSelfValue(kv.path) === undefined
+    )
+  })
+}
+
 ToSignalK.prototype._transform = function (chunk, encoding, done) {
   try {
     const delta = this.n2kMapper.toDelta(chunk)
@@ -137,6 +148,16 @@ ToSignalK.prototype._transform = function (chunk, encoding, done) {
         return
       }
 
+      //filter out static AIS data for self if configured
+      if (
+        delta.context == this.app.selfContext &&
+        aisPGNs.indexOf(chunk.pgn) !== -1
+      ) {
+        delta.updates[0].values = this.filterSelfAISStatic(
+          delta.updates[0].values
+        )
+      }
+
       delta.updates.forEach((update) => {
         update.values.forEach((kv) => {
           if (kv.path && kv.path.startsWith('notifications.')) {