Convert Presence to TS

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

src/Presence.ts

@@ -0,0 +1,110 @@
+/*
+Copyright 2015, 2016 OpenMarket Ltd
+Copyright 2018 New Vector Ltd
+Copyright 2019 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import {MatrixClientPeg} from "./MatrixClientPeg";
+import dis from "./dispatcher/dispatcher";
+import Timer from './utils/Timer';
+import {ActionPayload} from "./dispatcher/payloads";
+
+// Time in ms after that a user is considered as unavailable/away
+const UNAVAILABLE_TIME_MS = 3 * 60 * 1000; // 3 mins
+
+enum State {
+    Online = "online",
+    Offline = "offline",
+    Unavailable = "unavailable",
+}
+
+class Presence {
+    private unavailableTimer: Timer = null;
+    private dispatcherRef: string = null;
+    private state: State = null;
+
+    /**
+     * Start listening the user activity to evaluate his presence state.
+     * Any state change will be sent to the homeserver.
+     */
+    public async start() {
+        this.unavailableTimer = new Timer(UNAVAILABLE_TIME_MS);
+        // the user_activity_start action starts the timer
+        this.dispatcherRef = dis.register(this.onAction);
+        while (this.unavailableTimer) {
+            try {
+                await this.unavailableTimer.finished();
+                this.setState(State.Unavailable);
+            } catch (e) { /* aborted, stop got called */ }
+        }
+    }
+
+    /**
+     * Stop tracking user activity
+     */
+    public stop() {
+        if (this.dispatcherRef) {
+            dis.unregister(this.dispatcherRef);
+            this.dispatcherRef = null;
+        }
+        if (this.unavailableTimer) {
+            this.unavailableTimer.abort();
+            this.unavailableTimer = null;
+        }
+    }
+
+    /**
+     * Get the current presence state.
+     * @returns {string} the presence state (see PRESENCE enum)
+     */
+    public getState() {
+        return this.state;
+    }
+
+    private onAction = (payload: ActionPayload) => {
+        if (payload.action === 'user_activity') {
+            this.setState(State.Online);
+            this.unavailableTimer.restart();
+        }
+    }
+
+    /**
+     * Set the presence state.
+     * If the state has changed, the homeserver will be notified.
+     * @param {string} newState the new presence state (see PRESENCE enum)
+     */
+    private async setState(newState: State) {
+        if (newState === this.state) {
+            return;
+        }
+
+        const oldState = this.state;
+        this.state = newState;
+
+        if (MatrixClientPeg.get().isGuest()) {
+            return; // don't try to set presence when a guest; it won't work.
+        }
+
+        try {
+            await MatrixClientPeg.get().setPresence(this.state);
+            console.info("Presence: %s", newState);
+        } catch (err) {
+            console.error("Failed to set presence: %s", err);
+            this.state = oldState;
+        }
+    }
+}
+
+export default new Presence();