updates to allow server communication

loc_chain_app/lib/main.dart

@@ -5,6 +5,7 @@ import 'package:loc_chain_app/widgets/navbar.dart';
 import 'package:flutter_udid/flutter_udid.dart';
 
 void main() async {
+  WidgetsFlutterBinding.ensureInitialized();
   runApp(App());
   (await SharedPreferences.getInstance())
       .setString('userName', await FlutterUdid.consistentUdid);
@@ -14,11 +15,10 @@ class App extends StatelessWidget {
   // This widget is the root of your application.
   @override
   Widget build(BuildContext context) {
-    Connect.stop();
     Connect.start();
 
     return MaterialApp(
-      title: 'Flutter Demo',
+      title: 'Loc-Chain',
       theme: ThemeData(
         primarySwatch: Colors.lightBlue,
       ),

loc_chain_app/lib/pages/home.dart

@@ -78,4 +78,6 @@ class _HomePageState extends State<HomePage> {
       content: Text(a.toString()),
     ));
   }
+
+  Future<void> reportExposure() async {}
 }

loc_chain_app/lib/util/transaction_manager.dart

@@ -1,3 +1,4 @@
+import 'package:flutter/material.dart';
 import 'package:flutter_udid/flutter_udid.dart';
 import 'package:loc_chain_app/util/keyfile_manager.dart';
 
@@ -19,3 +20,50 @@ class Transaction {
   Future<String> generateP2PPayload(String otherUserId) async =>
       "${await generateHash(otherUserId)}:${KeyFileManager.keyPair.publicKey}";
 }
+
+class EncounterTransaction {
+  EncounterTransaction({
+    required this.combinedHash,
+    required this.encodedGPSLocation,
+    required this.partnerPublicKey,
+    required this.validationSignature,
+  }) : timestamp = "${DateTime.now().millisecondsSinceEpoch}";
+  final String combinedHash;
+  final String timestamp;
+  final String encodedGPSLocation;
+  final String partnerPublicKey;
+  final String validationSignature;
+
+  EncounterTransaction.fromJson(Map<String, dynamic> json)
+      : combinedHash = json['combinedHash'],
+        timestamp = json['timestamp'],
+        encodedGPSLocation = json['encodedGPSLocation'],
+        partnerPublicKey = json['partnerPublicKey'],
+        validationSignature = json['validationSignature'];
+
+  Map<String, dynamic> toJson() => {
+        "combinedHash": combinedHash,
+        "timestamp": timestamp,
+        "encodedGPSLocation": encodedGPSLocation,
+        "partnerPublicKey": partnerPublicKey,
+        "validationSignature": validationSignature,
+      };
+}
+
+class ExposureTransaction {
+  final String clientID;
+  final String timestamp;
+
+  ExposureTransaction({
+    required this.clientID,
+  }) : timestamp = "${DateTime.now().millisecondsSinceEpoch}";
+
+  ExposureTransaction.fromJson(Map<String, dynamic> json)
+      : clientID = json['clientID'],
+        timestamp = json['timestamp'];
+
+  Map<String, dynamic> toJson() => {
+        "clientID": clientID,
+        "timestamp": timestamp,
+      };
+}