feat(route building): add time constraint for departure requests

lib/api_handler.dart

@@ -6,6 +6,14 @@ import 'dart:convert';
 
 import 'transport_helper.dart';
 
+String timeOf(DateTime fullDT) {
+  // doing it this way so we always get two digits on the hour
+  String full = fullDT.toString();
+  List<String> splits = full.split(" ")[1].split(":");
+  String time = '${splits[0]}:${splits[1]}';
+  return time;
+}
+
 class ApiHandler {
   // TODO: Split next line for better Error Handling
   static final String baseUrl = dotenv.get("VBB_API_URL");
@@ -79,6 +87,7 @@ class ApiHandler {
   static Future<List<Departure>> departures(
     String stationId, {
     int? maxDepartures = -1,
+    DateTime? time,
     int? duration = 0,
   }) async {
     String urlPath = '/api/fahrinfo/latest/departureBoard';
@@ -87,7 +96,9 @@ class ApiHandler {
     Uri url = Uri.https(baseUrl, urlPath, {
       'accessId': accessID,
       'id': stationString,
-      ////'time': /current time //time from which departures will be shown
+      'time': timeOf(
+        time ?? DateTime.now(),
+      ), //time from which departures will be shown
       'duration': duration.toString(), //interval time in minutes
       'maxJourneys': maxDepartures.toString(),
       //'type': 'S', // Station/Stops only