do some horribly wrong timezone magic

diff --git a/web/static/seepark_web.js b/web/static/seepark_web.js
index 1390cd7..e663296 100644 (file)
--- a/web/static/seepark_web.js
+++ b/web/static/seepark_web.js
@@ -125,8 +125,13 @@ function loaddays(days) {
 
 function beginend(days) {
        var now = Date.now();
-       var end = new Date(now).toISOString().substr(0, 19); // 2018-06-13T16:52:30.995Z
-       var begin = new Date(now - days * 60*60*24 * 1000).toISOString().substr(0, 19);
+
+       // TODO: this timezone calculation relies on the browser being in Europe/Vienna
+       var refdate = new Date(now);
+       var offset = refdate.getTimezoneOffset(); // -120 for UTC+2
+
+       var end = new Date(now - offset * 60 * 1000).toISOString().substr(0, 19); // 2018-06-13T16:52:30.995Z
+       var begin = new Date(now - days * 60*60*24 * 1000 - offset * 60 * 1000).toISOString().substr(0, 19);
        return '&begin=' + begin + '&end=' + end;
 }