[Event] Add functions to remove and resend an error event

lib/src/Event.dart

@@ -22,6 +22,7 @@
  */
 
 import 'dart:convert';
+import 'package:famedlysdk/src/sync/EventUpdate.dart';
 import 'package:famedlysdk/src/utils/ChatTime.dart';
 import 'package:famedlysdk/src/Client.dart';
 import './User.dart';
@@ -148,6 +149,28 @@ class Event {
     );
   }
 
+  /// Removes this event if the status is < 1. This event will just be removed
+  /// from the database and the timelines.
+  Future<dynamic> remove() async {
+    if (status < 1) {
+      room.client.connection.onEvent.add(EventUpdate(
+          roomID: room.id,
+          type: "timeline",
+          eventType: environment,
+          content: {
+            "event_id": id,
+            "status": -2,
+          }));
+    }
+  }
+
+  /// Try to send this event again. Only works with events of status -1.
+  Future<dynamic> sendAgain({String txid}) async {
+    if (status != -1) return;
+    remove();
+    room.sendTextEvent(text, txid: txid);
+  }
+
   @Deprecated("Use [client.store.getEventList(Room room)] instead!")
   static Future<List<Event>> getEventList(Client matrix, Room room) async {
     List<Event> eventList = await matrix.store.getEventList(room);
@@ -176,6 +199,7 @@ enum EventTypes {
 }
 
 final Map<String, int> StatusTypes = {
+  "REMOVE": -2,
   "ERROR": -1,
   "SENDING": 0,
   "SENT": 1,

lib/src/Store.dart

@@ -220,7 +220,10 @@ class Store {
       }
 
       // Save the event in the database
-      if ((status == 1 || status == -1) &&
+      if (status == -2) {
+        txn.rawDelete(
+            "DELETE FROM Events WHERE id=?", [eventContent["event_id"]]);
+      } else if ((status == 1 || status == -1) &&
           eventUpdate.content["txid"] is String)
         txn.rawUpdate("UPDATE Events SET status=?, id=?, WHERE id=?",
             [status, eventContent["event_id"], eventUpdate.content["txid"]]);

lib/src/Timeline.dart

@@ -43,28 +43,37 @@ class Timeline {
     sub ??= room.client.connection.onEvent.stream.listen(_handleEventUpdate);
   }
 
+  int _findEvent({String event_id, String txid, String unsigned_txid}) {
+    int i;
+    for (i = 0; i < events.length; i++) {
+      if (events[i].content.containsKey("txid") &&
+              events[i].content["txid"] == txid ||
+          events[i].id == event_id ||
+          (events[i].content["txid"] == unsigned_txid)) break;
+    }
+    return i;
+  }
+
   void _handleEventUpdate(EventUpdate eventUpdate) async {
     try {
       if (eventUpdate.roomID != room.id) return;
       if (eventUpdate.type == "timeline" || eventUpdate.type == "history") {
+        if (eventUpdate.content["status"] == -2) {
+          int i = _findEvent(event_id: eventUpdate.content["event_id"]);
+          if (i < events.length) events.removeAt(i);
+        }
         // Is this event already in the timeline?
-        if (eventUpdate.content["status"] == 1 ||
+        else if (eventUpdate.content["status"] == 1 ||
             eventUpdate.content["status"] == -1 ||
             (eventUpdate.content.containsKey("unsigned") &&
                 eventUpdate.content["unsigned"]["transaction_id"] is String)) {
-          int i;
-          for (i = 0; i < events.length; i++) {
-            if (events[i].content.containsKey("txid") &&
-                    events[i].content["txid"] ==
-                        eventUpdate.content["content"]["txid"] ||
-                events[i].id == eventUpdate.content["event_id"] ||
-                (eventUpdate.content.containsKey("unsigned") &&
-                    eventUpdate.content["unsigned"]["transaction_id"]
-                        is String &&
-                    events[i].content["txid"] ==
-                        eventUpdate.content["unsigned"]["transaction_id"]))
-              break;
-          }
+          int i = _findEvent(
+              event_id: eventUpdate.content["event_id"],
+              txid: eventUpdate.content["content"]["txid"],
+              unsigned_txid: eventUpdate.content.containsKey("unsigned")
+                  ? eventUpdate.content["unsigned"]["transaction_id"]
+                  : null);
+
           if (i < events.length) {
             events[i] = Event.fromJson(eventUpdate.content, room);
           }

test/Timeline_test.dart

@@ -161,5 +161,31 @@ void main() {
       expect(timeline.events[2].content["txid"], "errortxid");
       expect(timeline.events[2].status, -1);
     });
+
+    test("Remove message", () async {
+      timeline.events[0].remove();
+
+      await new Future.delayed(new Duration(milliseconds: 50));
+
+      expect(updateCount, 13);
+
+      expect(insertList, [0, 0, 0, 0, 0, 0, 0]);
+      expect(timeline.events.length, 6);
+      expect(timeline.events[0].content["txid"], "errortxid2");
+      expect(timeline.events[0].status, -1);
+    });
+
+    test("Resend message", () async {
+      timeline.events[0].sendAgain(txid: "1234");
+
+      await new Future.delayed(new Duration(milliseconds: 50));
+
+      expect(updateCount, 16);
+
+      expect(insertList, [0, 0, 0, 0, 0, 0, 0, 0]);
+      expect(timeline.events.length, 6);
+      expect(timeline.events[0].content["txid"], "1234");
+      expect(timeline.events[0].status, 1);
+    });
   });
 }