Calling support

ts/util/Sound.ts

@@ -0,0 +1,75 @@
+export type SoundOpts = {
+  loop?: boolean;
+  src: string;
+};
+
+export class Sound {
+  static sounds = new Map();
+
+  private readonly context = new AudioContext();
+  private readonly loop: boolean;
+  private node?: AudioBufferSourceNode;
+  private readonly src: string;
+
+  constructor(options: SoundOpts) {
+    this.loop = Boolean(options.loop);
+    this.src = options.src;
+  }
+
+  async play() {
+    if (!Sound.sounds.has(this.src)) {
+      try {
+        const buffer = await Sound.loadSoundFile(this.src);
+        const decodedBuffer = await this.context.decodeAudioData(buffer);
+        Sound.sounds.set(this.src, decodedBuffer);
+      } catch (err) {
+        window.log.error(`Sound error: ${err}`);
+        return;
+      }
+    }
+
+    const soundBuffer = Sound.sounds.get(this.src);
+
+    const soundNode = this.context.createBufferSource();
+    soundNode.buffer = soundBuffer;
+
+    const volumeNode = this.context.createGain();
+    soundNode.connect(volumeNode);
+    volumeNode.connect(this.context.destination);
+
+    soundNode.loop = this.loop;
+
+    soundNode.start(0, 0);
+
+    this.node = soundNode;
+  }
+
+  stop() {
+    if (this.node) {
+      this.node.stop(0);
+      this.node = undefined;
+    }
+  }
+
+  static async loadSoundFile(src: string): Promise<ArrayBuffer> {
+    const xhr = new XMLHttpRequest();
+
+    xhr.open('GET', src, true);
+    xhr.responseType = 'arraybuffer';
+
+    return new Promise((resolve, reject) => {
+      xhr.onload = () => {
+        if (xhr.status === 200) {
+          resolve(xhr.response);
+          return;
+        }
+
+        reject(new Error(`Request failed: ${xhr.statusText}`));
+      };
+      xhr.onerror = () => {
+        reject(new Error(`Request failed, most likely file not found: ${src}`));
+      };
+      xhr.send();
+    });
+  }
+}