Support future sending via Widget API (MSC4157)

Depends on matrix-org/matrix-widget-api#90

Author: AndrewFerr

src/embedded.ts

@@ -27,7 +27,7 @@ import {
 
 import { MatrixEvent, IEvent, IContent, EventStatus } from "./models/event";
 import { ISendEventResponse, SendFutureRequestOpts, SendFutureResponse } from "./@types/requests";
-import { EventType } from "./@types/event";
+import { EventType, StateEvents } from "./@types/event";
 import { logger } from "./logger";
 import {
     MatrixClient,
@@ -260,8 +260,20 @@ export class RoomWidgetClient extends MatrixClient {
         futureOpts?: SendFutureRequestOpts,
     ): Promise<ISendEventResponse | SendFutureResponse> {
         if (futureOpts) {
-            throw new Error("Future sending via widgets is not implemented");
+            // TODO: updatePendingEvent for futures?
+            const response = await this.widgetApi.sendRoomEvent(
+                event.getType(),
+                event.getContent(),
+                room.roomId,
+                "future_timeout" in futureOpts ? futureOpts.future_timeout : undefined,
+                "parent_future_id" in futureOpts ? futureOpts.parent_future_id : undefined,
+            );
+            if (!response.future_id) {
+                throw new Error("'future_id' absent from response to a futures request");
+            }
+            return { future_id: response.future_id };
         }
+
         let response: ISendEventFromWidgetResponseData;
         try {
             response = await this.widgetApi.sendRoomEvent(event.getType(), event.getContent(), room.roomId);
@@ -271,6 +283,9 @@ export class RoomWidgetClient extends MatrixClient {
         }
 
         room.updatePendingEvent(event, EventStatus.SENT, response.event_id);
+        if (!response.event_id) {
+            throw new Error("'event_id' absent from response to an event request");
+        }
         return { event_id: response.event_id };
     }
 
@@ -280,7 +295,33 @@ export class RoomWidgetClient extends MatrixClient {
         content: any,
         stateKey = "",
     ): Promise<ISendEventResponse> {
-        return await this.widgetApi.sendStateEvent(eventType, stateKey, content, roomId);
+        const response = await this.widgetApi.sendStateEvent(eventType, stateKey, content, roomId);
+        if (response.event_id === undefined) {
+            throw new Error("'event_id' absent from response to an event request");
+        }
+        return { event_id: response.event_id };
+    }
+
+    /**
+     * @experimental This currently relies on an unstable MSC (MSC4140).
+     */
+    // eslint-disable-next-line
+    public async _unstable_sendStateFuture<K extends keyof StateEvents>(
+        roomId: string,
+        futureOpts: SendFutureRequestOpts,
+        eventType: K,
+        content: StateEvents[K],
+        stateKey = "",
+    ): Promise<SendFutureResponse> {
+        // TODO: better type checking
+        return (await this.widgetApi.sendStateEvent(
+            eventType,
+            stateKey,
+            content,
+            roomId,
+            "future_timeout" in futureOpts ? futureOpts.future_timeout : undefined,
+            "parent_future_id" in futureOpts ? futureOpts.parent_future_id : undefined,
+        )) as SendFutureResponse;
     }
 
     public async sendToDevice(eventType: string, contentMap: SendToDeviceContentMap): Promise<{}> {