feat: (broken) implement route map and address autocomplete widgets with associated infrastructure testing scripts

em2rp/scratch/test_user_route.dart

@@ -0,0 +1,81 @@
+import 'dart:convert';
+import 'dart:io';
+
+void main() async {
+  final envFile = File('functions/.env');
+  final lines = await envFile.readAsLines();
+  String apiKey = '';
+  for (var line in lines) {
+    if (line.startsWith('API_MAPS=')) {
+      apiKey = line.split('=')[1].replaceAll('"', '');
+    }
+  }
+
+  final url = 'https://routes.googleapis.com/directions/v2:computeRoutes';
+  final client = HttpClient();
+  
+  final request = await client.postUrl(Uri.parse(url));
+  request.headers.set('Content-Type', 'application/json');
+  request.headers.set('X-Goog-Api-Key', apiKey);
+  request.headers.set('X-Goog-FieldMask', 'routes.distanceMeters,routes.duration,routes.polyline.encodedPolyline');
+  
+  final payload = jsonEncode({
+    "travelMode": "DRIVE",
+    "routingPreference": "TRAFFIC_AWARE",
+    "routeModifiers": { "avoidTolls": true },
+    "origin": { "address": "401 route du camping, 69850 Saint Martin en haut" },
+    "destination": { "address": "25 Imp. du Puits du Suc, Saint-Martin-en-Haut, France" }
+  });
+  
+  request.write(payload);
+  final response = await request.close();
+  final responseBody = await response.transform(utf8.decoder).join();
+  
+  try {
+    final json = jsonDecode(responseBody);
+    final routes = json['routes'] as List;
+    final polyStr = routes[0]['polyline']['encodedPolyline'] as String;
+    
+    print("Polyline found. Length: ${polyStr.length}");
+    print("String: $polyStr");
+    
+    int index = 0, len = polyStr.length;
+    int lat = 0, lng = 0;
+    List poly = [];
+    while (index < len) {
+      int b, shift = 0, result = 0;
+      do {
+        b = polyStr.codeUnitAt(index++) - 63;
+        result |= (b & 0x1f) << shift;
+        shift += 5;
+      } while (b >= 0x20);
+      int dlat = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
+      lat += dlat;
+
+      shift = 0;
+      result = 0;
+      do {
+        b = polyStr.codeUnitAt(index++) - 63;
+        result |= (b & 0x1f) << shift;
+        shift += 5;
+      } while (b >= 0x20);
+      int dlng = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
+      lng += dlng;
+
+      double finalLat = lat / 1e5;
+      double finalLng = lng / 1e5;
+      
+      if (finalLat.abs() > 90.0 || finalLng.abs() > 180.0) {
+        print("EXPLODED at index $index: $finalLat, $finalLng");
+        break;
+      }
+      poly.add([finalLat, finalLng]);
+    }
+    print("Decode complete. Points:");
+    for (var pt in poly) {
+      print(pt);
+    }
+  } catch (e) {
+    print("Error: $e");
+  }
+}