1. transport_mode depends on origin and 2. pickup timetable

static/stops.js

@@ -111,6 +111,9 @@
     if (!hidden) return;
 
     function clearMatch() {
+      delete hidden.dataset.stopType;
+      delete hidden.dataset.stopLat;
+      delete hidden.dataset.stopLon;
       if (!hidden.value) return;
       hidden.value = "";
       if (hint) { hint.textContent = ""; hint.classList.remove("matched"); }
@@ -118,6 +121,9 @@
     }
     function markMatch(stop) {
       hidden.value = String(stop.id);
+      hidden.dataset.stopType = stop.type;
+      hidden.dataset.stopLat = stop.lat;
+      hidden.dataset.stopLon = stop.lon;
       if (hint) {
         hint.textContent = "✓ " + stop.name +
           (stop.municipality ? ", " + stop.municipality : "");
@@ -223,8 +229,88 @@
     });
   }
 
+  // Which "Verkehrsmittel" options make sense for a given origin stop type.
+  // Rail stops aren't narrowed further (OSM doesn't tell S-Bahn from Fernzug).
+  var MODES_FOR_STOP_TYPE = {
+    bus: ["Bus"],
+    bus_station: ["Bus"],
+    tram: ["Straßenbahn"],
+    subway: ["U-Bahn"],
+    train: ["S-Bahn", "Regionalzug", "Fernzug (ÖBB/Railjet/WESTbahn)"],
+  };
+
+  function setupModeFilter(form) {
+    var select = form.querySelector("#transport_mode");
+    var originHidden = form.querySelector("#origin_stop_id");
+    if (!select || !originHidden) return;
+    var hint = form.querySelector("[data-mode-hint]");
+
+    function apply() {
+      var allowed = MODES_FOR_STOP_TYPE[originHidden.dataset.stopType || ""] || null;
+      var firstVisible = null;
+      Array.prototype.forEach.call(select.options, function (opt) {
+        var ok = !allowed || allowed.indexOf(opt.value) !== -1;
+        opt.hidden = !ok;
+        opt.disabled = !ok;
+        if (ok && !firstVisible) firstVisible = opt;
+      });
+      if (allowed && firstVisible && allowed.indexOf(select.value) === -1) {
+        select.value = firstVisible.value;
+      }
+      if (hint) {
+        hint.textContent = allowed
+          ? "Eingeschränkt auf das Verkehrsmittel der gewählten Haltestelle."
+          : "";
+      }
+    }
+
+    form.addEventListener("stopchange", apply);
+    apply(); // e.g. an already-matched origin when editing a trip
+  }
+
+  // "Fahrplan öffnen": opens Google Maps transit directions for the chosen
+  // stops (exact coordinates when matched, else the typed name) so the user
+  // can look up the real departure and copy it into the "Kurs" field.
+  function setupTimetableLink(form) {
+    var link = form.querySelector("[data-timetable-link]");
+    var originText = form.querySelector("#origin");
+    var destText = form.querySelector("#destination");
+    var originHidden = form.querySelector("#origin_stop_id");
+    var destHidden = form.querySelector("#destination_stop_id");
+    if (!link || !originText || !destText || !originHidden || !destHidden) return;
+
+    function locationParam(textInput, hiddenInput) {
+      var lat = hiddenInput.dataset.stopLat, lon = hiddenInput.dataset.stopLon;
+      if (lat && lon) return lat + "," + lon;
+      var name = textInput.value.trim();
+      return name ? name + ", Österreich" : "";
+    }
+
+    function apply() {
+      var origin = locationParam(originText, originHidden);
+      var destination = locationParam(destText, destHidden);
+      if (!origin || !destination) {
+        link.removeAttribute("href");
+        link.setAttribute("aria-disabled", "true");
+        return;
+      }
+      link.href = "https://www.google.com/maps/dir/?api=1" +
+        "&origin=" + encodeURIComponent(origin) +
+        "&destination=" + encodeURIComponent(destination) +
+        "&travelmode=transit";
+      link.removeAttribute("aria-disabled");
+    }
+
+    form.addEventListener("stopchange", apply);
+    originText.addEventListener("input", apply);
+    destText.addEventListener("input", apply);
+    apply();
+  }
+
   document.querySelectorAll("form").forEach(function (form) {
     form.querySelectorAll("[data-stop-input]").forEach(function (i) { setupStopCombo(i, form); });
     form.querySelectorAll("[data-line-input]").forEach(function (i) { setupLineCombo(i, form); });
+    setupModeFilter(form);
+    setupTimetableLink(form);
   });
 })();