added translations

frontend/public/js/dates.js

@@ -1,6 +1,7 @@
 // Shared date-range handling for Browse Events and both maps — remembered
 // across pages the way location.js remembers the place, validated in one
-// spot, and bound to German-format (dd.mm.yyyy) date pickers. Pages still
+// spot, and bound to date pickers shown in the page language (format and
+// calendar names from i18n.js / the flatpickr locale). Pages still
 // own what a range *does* (a server-side filter on Browse, a client-side
 // one on the maps); this only owns the range itself.
 (function (window) {
@@ -64,11 +65,12 @@
     } catch (e) { /* localStorage disabled/unavailable */ }
   }
 
-  // Turns a pair of <input type="date"> into German-format pickers when
-  // flatpickr is loaded. A native date input displays in the *browser's*
-  // locale and can't be forced to dd.mm.yyyy, so the visible field is
-  // flatpickr's alt input (d.m.Y, German calendar) while the original input
-  // keeps holding the machine-readable "Y-m-d" value everything else reads.
+  // Turns a pair of <input type="date"> into pickers in the page language
+  // when flatpickr is loaded. A native date input displays in the *browser's*
+  // locale and can't be forced to the site's format, so the visible field is
+  // flatpickr's alt input (e.g. d.m.Y with a German calendar) while the
+  // original input keeps holding the machine-readable "Y-m-d" value
+  // everything else reads.
   // Without flatpickr (e.g. its CDN is unreachable) the native inputs keep
   // working as they are.
   //
@@ -79,10 +81,12 @@
     var pickers = [];
     if (window.flatpickr) {
       var options = {
-        locale: 'de',
+        // flatpickr ships a file per language (loaded by
+        // _datepicker_scripts.html.twig); English is built in.
+        locale: (window.flatpickr.l10ns && window.flatpickr.l10ns[window.VindnI18n.locale]) ? window.VindnI18n.locale : 'default',
         dateFormat: 'Y-m-d',
         altInput: true,
-        altFormat: 'd.m.Y',
+        altFormat: window.VindnI18n.dateFormat,
         allowInput: true,
         disableMobile: true, // the native mobile picker would bring the device locale back
         static: true, // rendered inside the card, so it also shows in a fullscreen map
@@ -105,7 +109,7 @@
         alt.id = el.id + 'Display';
         if (label) label.setAttribute('for', alt.id);
         alt.setAttribute('aria-label', el.getAttribute('aria-label') || '');
-        alt.setAttribute('placeholder', 'TT.MM.JJJJ');
+        alt.setAttribute('placeholder', window.VindnI18n.t('dates.placeholder'));
         return picker;
       });
     }