From f8a6b9eb96fc397cc1e8814478c892eb0724d40b Mon Sep 17 00:00:00 2001
From: Mischa <mischa@gorinskat.nl>
Date: Mon, 22 Jun 2026 23:22:48 +0200
Subject: [PATCH] feat: add parseGpxFiles and export haversineKm from MapUtils

---
 themes/intotheeast/js/maplibre-utils.js | 89 +++++++++++++++++++++++++
 1 file changed, 89 insertions(+)

diff --git a/themes/intotheeast/js/maplibre-utils.js b/themes/intotheeast/js/maplibre-utils.js
index c0b3511..4e12689 100644
--- a/themes/intotheeast/js/maplibre-utils.js
+++ b/themes/intotheeast/js/maplibre-utils.js
@@ -330,9 +330,98 @@
     });
   }
 
+  /*
+   * Parse one or more GPX files and compute aggregate cycling statistics.
+   * urls:     array of GPX file URL strings
+   * callback: called once with { distance, eleGain, eleLoss, highest, lowest, movingTime, avgSpeed }
+   *           or { error: 'no files' } if urls is empty.
+   *
+   * distance/eleGain/eleLoss in raw units (km / metres).
+   * movingTime: "H:MM" string. avgSpeed: km/h number.
+   */
+  function parseGpxFiles(urls, callback) {
+    var pending = urls.length;
+    var fileResults = new Array(urls.length);
+    if (pending === 0) { callback({ error: 'no files' }); return; }
+
+    urls.forEach(function (url, idx) {
+      fetch(url)
+        .then(function (r) { return r.text(); })
+        .then(function (text) {
+          var xml  = new DOMParser().parseFromString(text, 'text/xml');
+          var pts  = [];
+          xml.querySelectorAll('trkpt').forEach(function (pt) {
+            var eleEl  = pt.querySelector('ele');
+            var timeEl = pt.querySelector('time');
+            pts.push({
+              lat:  parseFloat(pt.getAttribute('lat')),
+              lon:  parseFloat(pt.getAttribute('lon')),
+              ele:  eleEl  ? parseFloat(eleEl.textContent)  : NaN,
+              time: timeEl ? timeEl.textContent              : null
+            });
+          });
+          fileResults[idx] = pts;
+          if (--pending === 0) computeAndCallback();
+        })
+        .catch(function (err) {
+          console.warn('GPX load failed:', url, err);
+          fileResults[idx] = [];
+          if (--pending === 0) computeAndCallback();
+        });
+    });
+
+    function computeAndCallback() {
+      var totalDistance = 0, totalEleGain = 0, totalEleLoss = 0;
+      var globalHighest = NaN, globalLowest = NaN, totalMovingTime = 0;
+
+      fileResults.forEach(function (pts) {
+        if (!pts || pts.length < 2) return;
+        /* Include first point of each file in elevation range */
+        if (!isNaN(pts[0].ele)) {
+          if (isNaN(globalHighest) || pts[0].ele > globalHighest) globalHighest = pts[0].ele;
+          if (isNaN(globalLowest)  || pts[0].ele < globalLowest)  globalLowest  = pts[0].ele;
+        }
+        for (var i = 1; i < pts.length; i++) {
+          var p0 = pts[i - 1], p1 = pts[i];
+          totalDistance += haversineKm(p0.lat, p0.lon, p1.lat, p1.lon);
+          if (!isNaN(p0.ele) && !isNaN(p1.ele)) {
+            var dEle = p1.ele - p0.ele;
+            if (dEle > 0) totalEleGain += dEle;
+            if (dEle < 0) totalEleLoss += (-dEle);
+            if (isNaN(globalHighest) || p1.ele > globalHighest) globalHighest = p1.ele;
+            if (isNaN(globalLowest)  || p1.ele < globalLowest)  globalLowest  = p1.ele;
+          }
+          if (p0.time && p1.time) {
+            var dtHrs = (Date.parse(p1.time) - Date.parse(p0.time)) / 3600000;
+            if (dtHrs > 0 && (haversineKm(p0.lat, p0.lon, p1.lat, p1.lon) / dtHrs) >= 1) {
+              totalMovingTime += dtHrs;
+            }
+          }
+        }
+      });
+
+      var avgSpeed  = totalMovingTime > 0 ? totalDistance / totalMovingTime : 0;
+      var movHours  = Math.floor(totalMovingTime);
+      var movMins   = Math.round((totalMovingTime - movHours) * 60);
+      if (movMins === 60) { movHours++; movMins = 0; }
+
+      callback({
+        distance:   totalDistance,
+        eleGain:    totalEleGain,
+        eleLoss:    totalEleLoss,
+        highest:    globalHighest,
+        lowest:     globalLowest,
+        movingTime: movHours + ':' + (movMins < 10 ? '0' : '') + movMins,
+        avgSpeed:   avgSpeed
+      });
+    }
+  }
+
   global.MapUtils = {
     MAP_STYLE:            MAP_STYLE,
     ACCENT:               ACCENT,
+    haversineKm:          haversineKm,
+    parseGpxFiles:        parseGpxFiles,
     addJourneyLine:       addJourneyLine,
     addJourneySegments:   addJourneySegments,
     buildJourneySegments: buildJourneySegments,