departure point can be null

Somtimes (for example https://www.sac-cas.ch/it/capanne-e-escursioni/portale-escursionistico-del-cas/albristhubel-6246/escursioni-con-le-racchette/von-matten-simmental-2785/)
segments.geom is null and the creation of the gpx xml subsequently fails.

If that is the case just ignore it and do not try to turn it into a
track segment.

Thanks to wizche for the report and fix!

.gitignore

@@ -1,3 +1,4 @@
 *~
 .DS_Store
 *.swp
+web-ext-artifacts

README.md

@@ -1,5 +1,4 @@
 # SAC Route Portal GPX Downloader
-
 The [Swiss Alpine Club](https://www.sac-cas.ch/en/) has a great 
 [route portal](https://www.sac-cas.ch/en/huts-and-tours/sac-route-portal/)
 for finding interesting hiking routes.
@@ -19,3 +18,6 @@ Heed their warning and do not blindly follow the gps track! Use your brain and
 plan your route beforehand to be aware of dangerous parts and alternatives. 
 
 Take a look at their [safety instructions](https://www.sac-cas.ch/en/training-and-safety/safety/).
+
+## Contributors
+- wizche

background.js

@@ -1,196 +1,255 @@
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
- 
+
 let gpxTrack = null;
 
 /**
  * Convert the Swiss projection coordinates to WGS84 (lat/lon).
- * 
+ *
- * Calculations from "Approximate formulas for the transformation between Swiss 
+ * Calculations from "Approximate formulas for the transformation between Swiss
- * projection coordinates and WGS84" by the Swiss Federal Office of Topography, 
+ * projection coordinates and WGS84" by the Swiss Federal Office of Topography,
- * swisstopo 
+ * swisstopo
  * (https://www.swisstopo.admin.ch/en/knowledge-facts/surveying-geodesy/reference-systems/map-projections.html).
- * 
+ *
+ * @param {*} point Array of Swiss projection coordinates, position 0 is E and 1 is N.
+ * @returns Calculated lat and lon.
+ */
+function toWGS84(point) {
+  // convert LV95 into the civilian system
+  const y_aux = (point[0] - 2600000) / 1000000;
+  const x_aux = (point[1] - 1200000) / 1000000;
+
+  // calculate longitude and latitude in the unit 10000"
+  let lat = 16.9023892 +
+    3.238272 * x_aux -
+    0.270978 * Math.pow(y_aux, 2) -
+    0.002528 * Math.pow(x_aux, 2) -
+    0.0447 * Math.pow(y_aux, 2) * x_aux -
+    0.014 * Math.pow(x_aux, 3);
+
+  let lon = 2.6779094 +
+    4.728982 * y_aux +
+    0.791484 * y_aux * x_aux +
+    0.1306 * y_aux * Math.pow(x_aux, 2) -
+    0.0436 * Math.pow(y_aux, 3);
+
+  // unit 10000" to 1" and seconds to degrees (dec)
+  lat = (lat * 100) / 36;
+  lon = (lon * 100) / 36;
+
+  return { lat: lat, lon: lon };
+}
+
+/**
+ * Get the gpx trackpoint representation of a Swiss projection coordinate point.
+ *
  * @param {*} point Array of Swiss projection coordinates, position 0 is E and 1 is N.
  * @returns Track point xml node for gpx.
  */
 function toTrackPoint(point) {
-    // convert LV95 into the civilian system
+  const wgs84Point = toWGS84(point);
-    let y_aux = (point[0] - 2600000)/1000000;
+  return `<trkpt lat="${wgs84Point.lat}" lon="${wgs84Point.lon}"/>`;
-	let x_aux = (point[1] - 1200000)/1000000;
+}
 
-    // calculate longitude and latitude in the unit 10000" 
+/**
-    let lat = 16.9023892 +
+ * Get the gpx waypoint representation of a route portal point.
-			3.238272 * x_aux -
+ *
-			0.270978 * Math.pow(y_aux, 2) -
+ * @returns Way point xml node for gpx.
-			0.002528 * Math.pow(x_aux, 2) -
+ */
-			0.0447	 * Math.pow(y_aux, 2) * x_aux -
+function toWayPoint(point) {
-			0.0140	 * Math.pow(x_aux, 3);
+  const wgs84Point = toWGS84(point.geom.coordinates);
-
+  return `
-    let lng = 2.6779094 +
+    <wpt lat="${wgs84Point.lat}" lon="${wgs84Point.lon}">
-			4.728982 * y_aux +
+        <ele>${point.altitude}</ele>
-			0.791484 * y_aux * x_aux +
+        <name>${point.display_name}</name>
-			0.1306	 * y_aux * Math.pow(x_aux, 2) -
+    </wpt>`;
-			0.0436	 * Math.pow(y_aux, 3);
-
-	// unit 10000" to 1" and seconds to degrees (dec)
-    lat = lat * 100 / 36;
-	lng = lng * 100 / 36;
-
-    return `<trkpt lat="${lat}" lon="${lng}"/>`;
 }
 
 /**
  * Create track title.
- * 
+ *
- * @param {*} geoJson 
+ * @param {*} geoJson
  * @returns Combined route number, id and route title.
  */
 function trackTitle(geoJson) {
-    const route = geoJson.segments[0];
+  const book = geoJson.book_route_number
-    return `${geoJson.book_route_number}-${route.route_id} ${route.title}`;
+    ? `${geoJson.book_route_number} - `
+    : "";
+
+  return `${book}${geoJson.title}`;
 }
 
 /**
  * Create a gpx representation from the sac GeoJSON data.
- * 
+ *
- * @param {*} geoJson 
+ * @param {*} geoJson
  * @returns Simple gpx string.
  */
 function toGpx(geoJson) {
-    const route = geoJson.segments[0].geom;
+  const trackSegments = geoJson.segments
-    const routeTitle = trackTitle(geoJson);
+    .map((segment) => {
+      if (segment.geom == null) return "";
+      return `<trkseg>
+             ${segment.geom.coordinates.map(toTrackPoint).join("")}
+         </trkseg>`;
+    })
+    .join("");
 
-    const xmlString = `<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
+  const departurePoint = geoJson.departure_point
+    ? toWayPoint(geoJson.departure_point)
+    : "";
+  const endPoint = geoJson.end_point ? toWayPoint(geoJson.end_point) : "";
+  const waypoints = geoJson.waypoints
+    ? geoJson.waypoints
+      .map((wp) => {
+        return toWayPoint(wp.reference_poi);
+      })
+      .join("")
+    : "";
+
+  const routeTitle = trackTitle(geoJson);
+
+  const xmlString = `<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
 
     <gpx xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xmlns="http://www.topografix.com/GPX/1/0"
         xsi:schemaLocation="http://www.topografix.com/GPX/1/0 http://www.topografix.com/GPX/1/0/gpx.xsd"
         version="1.0"
         creator="SAC-Tourenportal GPX Downloader">
+      ${departurePoint}
+      ${toWayPoint(geoJson.destination_poi)}
+      ${waypoints}
+      ${endPoint}
       <trk>
         <name>Track ${routeTitle}</name>
-        <trkseg>
+        ${trackSegments}
-            ${route.coordinates.map(toTrackPoint).join("")}
-        </trkseg>
       </trk>
     </gpx>
     `;
 
-    const parser = new DOMParser();
+  const parser = new DOMParser();
-    let xmlDoc = parser.parseFromString(xmlString, "text/xml");
+  const xmlDoc = parser.parseFromString(xmlString, "text/xml");
 
-    return new XMLSerializer().serializeToString(xmlDoc.documentElement);
+  return new XMLSerializer().serializeToString(xmlDoc.documentElement);
 }
 
 /**
  * Intercept the download of GeoJSON data and save it for the background script.
  */
 function listener(details) {
-    let filter = browser.webRequest.filterResponseData(details.requestId);
+  const filter = browser.webRequest.filterResponseData(details.requestId);
-    let decoder = new TextDecoder("utf-8");
+  const decoder = new TextDecoder("utf-8");
-    let encoder = new TextEncoder();
+  const encoder = new TextEncoder();
 
-    let data = [];
+  const data = [];
-    filter.ondata = event => {
+  filter.ondata = (event) => {
-        data.push(event.data);
+    data.push(event.data);
-    };
+  };
 
-    filter.onstop = async event => {
+  filter.onstop = async (_event) => {
-        let blob = new Blob(data, {type: 'text/html'});
+    const blob = new Blob(data, { type: "text/html" });
-        let buffer = await blob.arrayBuffer();
+    const buffer = await blob.arrayBuffer();
-        let str = decoder.decode(buffer);
+    const str = decoder.decode(buffer);
 
-        gpxTrack = JSON.parse(str);
+    updateActiveTab(browser.tabs);
-        updateActiveTab(browser.tabs);
 
-        filter.write(encoder.encode(str));
+    filter.write(encoder.encode(str));
-        filter.close();
+    filter.close();
-    };
 
-    return {};
+    const geoJson = JSON.parse(str);
+    const routeTitle = trackTitle(geoJson);
+    gpxTrack = { title: routeTitle, data: toGpx(geoJson) };
+  };
+
+  return {};
 }
 
 /**
  * Check if a url should be intercepted.
- * 
+ *
- * @param {*} tab 
+ * @param {*} tab
  * @returns True if the active tab is an sac website, false otherwise.
  */
 function checkTrack(tab) {
-    if (!tab.url) {
+  if (!tab.url) {
-        return false;
+    return false;
-    }
+  }
 
-    return tab.url.match("https://www.sac-cas.ch/.*") && gpxTrack;
+  return tab.url.match("https://www.sac-cas.ch/.*") && gpxTrack;
 }
 
 /**
  * If a valid tack was selected, download it as a gpx file.
  */
 function handleClick(tab) {
-    const hasTrack = checkTrack(tab);
+  const hasTrack = checkTrack(tab);
-    if (!hasTrack) {
+  if (!hasTrack) {
-        return;
+    return;
-    }
+  }
 
-    let blob = new Blob([toGpx(gpxTrack)], {type: "application/gpx+xml"});
+  const blob = new Blob([gpxTrack.data], { type: "application/gpx+xml" });
-    let objectURL = URL.createObjectURL(blob);
+  const objectURL = URL.createObjectURL(blob);
 
-    const routeTitle = trackTitle(gpxTrack);
+  const downloading = browser.downloads.download({
+    url: objectURL,
+    filename: `${gpxTrack.title}.gpx`,
+    saveAs: true,
+    conflictAction: "uniquify",
+  });
 
-    let downloading = browser.downloads.download({
+  downloading.then(
-        url : objectURL,
+    (id) => console.log(`Started downloading: ${id}`),
-        filename : `track-${routeTitle}.gpx`,
+    (error) => console.log(`Download failed: ${error}`),
-        saveAs: true,
+  );
-        conflictAction : 'uniquify'
+  gpxTrack = null;
-      });
-      
-    downloading.then(
-        (id) => console.log(`Started downloading: ${id}`), 
-        (error) => console.log(`Download failed: ${error}`));
-    gpxTrack = null;
 }
 
 /**
  * Update the download icon and text.
  */
-function updateActiveTab(tabs) {
+function updateActiveTab(_tabs) {
-    function updateTab(tabs) {
+  function updateTab(tabs) {
-      if (tabs[0]) {
+    if (tabs[0]) {
-        updateIcon(tabs[0]);
+      updateIcon(tabs[0]);
-      }
     }
-  
+  }
-    let gettingActiveTab = browser.tabs.query({active: true, currentWindow: true});
+
-    gettingActiveTab.then(updateTab);
+  const gettingActiveTab = browser.tabs.query({
+    active: true,
+    currentWindow: true,
+  });
+  gettingActiveTab.then(updateTab);
 }
 
 /**
  * Update the download icon.
  */
 function updateIcon(tab) {
-    const hasTrack = checkTrack(tab);
+  const hasTrack = checkTrack(tab);
 
-    browser.browserAction.setIcon({
+  browser.browserAction.setIcon({
-      path: hasTrack ? {
+    path: hasTrack
+      ? {
         48: "icons/map.png",
-      } : {
+      }
+      : {
         48: "icons/map-disabled.png",
       },
-      tabId: tab.id
+    tabId: tab.id,
-    });
+  });
-    browser.browserAction.setTitle({
+  browser.browserAction.setTitle({
-      title: hasTrack ? `Download track ${trackTitle(gpxTrack)}` : 'No track selected',
+    title: hasTrack
-      tabId: tab.id
+      ? `Download track "${gpxTrack.title}"`
-    }); 
+      : "No track selected",
+    tabId: tab.id,
+  });
 }
 
 browser.webRequest.onBeforeRequest.addListener(
-    listener,
+  listener,
-    {urls: ["https://www.sac-cas.ch/*[routeId]*"]},
+  { urls: ["https://www.sac-cas.ch/*[routeId]*"] },
-    ["blocking"]
+  ["blocking"],
 );
 
 browser.browserAction.onClicked.addListener(handleClick);
@@ -198,5 +257,5 @@ browser.browserAction.onClicked.addListener(handleClick);
 browser.tabs.onUpdated.addListener(updateActiveTab);
 browser.tabs.onActivated.addListener(updateActiveTab);
 browser.windows.onFocusChanged.addListener(updateActiveTab);
-  
+
 updateActiveTab();

manifest.json

@@ -1,19 +1,15 @@
 {
-
     "manifest_version": 2,
-    "name": "SAC Route Portal GPX",
+    "name": "SAC Route Portal GPX Downloader",
-    "version": "0.1",
+    "version": "0.8",
     "developer": {
         "name": "Sebastian Hugentobler",
         "url": "https://code.vanwa.ch/sebastian/sac-route-portal-gpx-fx"
     },
-
     "description": "Download gpx tracks from the sac route portal.",
-
     "icons": {
         "48": "icons/map.png"
     },
-
     "permissions": [
         "activeTab",
         "downloads",
@@ -21,13 +17,13 @@
         "webRequestBlocking",
         "https://www.sac-cas.ch/*"
     ],
-    
     "background": {
-        "scripts": ["background.js"]
+        "scripts": [
+            "background.js"
+        ]
     },
-
     "browser_action": {
         "default_icon": "icons/map.png",
         "default_title": "To GPX"
-      }
+    }
 }