From 2886bd49432b2e472df20486f65db0de45ed62f6 Mon Sep 17 00:00:00 2001
From: "D. Berge" <dberge@aaltronav.eu>
Date: Mon, 28 Sep 2020 21:43:24 +0200
Subject: [PATCH] Do not react to events until we have at least two of them.

This is to avoid false positives when restarting the API
mid-line.
---
 lib/www/server/events/index.js | 61 +++++++++++++++++-----------------
 1 file changed, 31 insertions(+), 30 deletions(-)

diff --git a/lib/www/server/events/index.js b/lib/www/server/events/index.js
index af31251..ada5c53 100644
--- a/lib/www/server/events/index.js
+++ b/lib/www/server/events/index.js
@@ -3,7 +3,7 @@ const { listen } = require('../ws/db');
 const { event } = require('../lib/db');
 
 function start () {
-	let prevPos = {};
+	let prevPos = null;
 	
 	listen(["realtime"], function (data) {
 		if (!(data.payload && data.payload.new && data.payload.new.meta)) {
@@ -12,37 +12,38 @@ function start () {
 		}
 		
 		const pos = data.payload.new.meta;
-// 		console.log("POS", pos);
-// 		console.log("status (C, P)", pos._sequence, pos._point, pos.lineStatus, prevPos._point, prevPos.lineStatus, pos.tstamp, prevPos.tstamp);
-		if (pos.lineStatus == "online") {
-			if (prevPos.lineStatus != "online") {
-				// FIXME TODO Check if there are already FSP, FGSP events for this sequence
-				// Tag this as FSP/FGSP
-				const remarks = `SEQ ${pos._sequence}, SOL ${pos.lineName}, BSP: ${(pos.speed*3.6/1.852).toFixed(1)} kt, Water depth: ${Number(pos.waterDepth).toFixed(0)} m.`;
-				const payload = {
-					type: "sequence",
-					sequence: pos._sequence,
-					point: pos._point,
-					remarks,
-					labels: [ "FSP", "FGSP" ]
+		
+		if (prevPos) {
+			if (pos.lineStatus == "online") {
+				if (prevPos.lineStatus != "online") {
+					// FIXME TODO Check if there are already FSP, FGSP events for this sequence
+					// Tag this as FSP/FGSP
+					const remarks = `SEQ ${pos._sequence}, SOL ${pos.lineName}, BSP: ${(pos.speed*3.6/1.852).toFixed(1)} kt, Water depth: ${Number(pos.waterDepth).toFixed(0)} m.`;
+					const payload = {
+						type: "sequence",
+						sequence: pos._sequence,
+						point: pos._point,
+						remarks,
+						labels: [ "FSP", "FGSP" ]
+					}
+					schema2pid(pos._schema).then(projectId => event.post(projectId, payload));
+	// 				console.log("post fsp", pos._schema);
 				}
-				schema2pid(pos._schema).then(projectId => event.post(projectId, payload));
-// 				console.log("post fsp", pos._schema);
-			}
-		} else {
-			if (prevPos.lineStatus == "online") {
-				// FIXME TODO Check if there are already LSP, LGSP events for this sequence
-				// Tag this as LSP/LGSP
-				const remarks = `SEQ ${prevPos._sequence}, EOL ${prevPos.lineName}, BSP: ${(prevPos.speed*3.6/1.852).toFixed(1)} kt, Water depth: ${Number(prevPos.waterDepth).toFixed(0)} m.`;
-				const payload = {
-					type: "sequence",
-					sequence: prevPos._sequence,
-					point: prevPos._point,
-					remarks,
-					labels: [ "LSP", "LGSP" ]
+			} else {
+				if (prevPos.lineStatus == "online") {
+					// FIXME TODO Check if there are already LSP, LGSP events for this sequence
+					// Tag this as LSP/LGSP
+					const remarks = `SEQ ${prevPos._sequence}, EOL ${prevPos.lineName}, BSP: ${(prevPos.speed*3.6/1.852).toFixed(1)} kt, Water depth: ${Number(prevPos.waterDepth).toFixed(0)} m.`;
+					const payload = {
+						type: "sequence",
+						sequence: prevPos._sequence,
+						point: prevPos._point,
+						remarks,
+						labels: [ "LSP", "LGSP" ]
+					}
+					schema2pid(prevPos._schema).then(projectId => event.post(projectId, payload));
+	// 				console.log("post lsp", prevPos._schema);
 				}
-				schema2pid(prevPos._schema).then(projectId => event.post(projectId, payload));
-// 				console.log("post lsp", prevPos._schema);
 			}
 		}