From 7e72d896519e4562f254801f1d427447ed4d4de7 Mon Sep 17 00:00:00 2001
From: 0xloem <0xloem@gmail.com>
Date: Thu, 17 Dec 2020 06:23:48 -0500
Subject: [PATCH] tell the user if bluetooth is missing

---
 demo/src/main.ts |  5 +++--
 src/muse.ts      | 10 +++++++++-
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/demo/src/main.ts b/demo/src/main.ts
index 5ae4200..19b6c50 100644
--- a/demo/src/main.ts
+++ b/demo/src/main.ts
@@ -23,7 +23,7 @@ import { channelNames, EEGReading, MuseClient } from './../../src/muse';
         context.clearRect(0, 0, canvas.width, canvas.height);
 
         for (let i = 0; i < reading.samples.length; i++) {
-            const sample = reading.samples[i] / 15.;
+            const sample = reading.samples[i] / 15;
             if (sample > 0) {
                 context.fillRect(i * 25, height - sample, width, sample);
             } else {
@@ -50,7 +50,7 @@ import { channelNames, EEGReading, MuseClient } from './../../src/muse';
             document.getElementById('batteryLevel')!.innerText = reading.batteryLevel.toFixed(2) + '%';
         });
         client.accelerometerData.subscribe((accel) => {
-            const normalize = (v: number) => (v / 16384.).toFixed(2) + 'g';
+            const normalize = (v: number) => (v / 16384).toFixed(2) + 'g';
             document.getElementById('accelerometer-x')!.innerText = normalize(accel.samples[2].x);
             document.getElementById('accelerometer-y')!.innerText = normalize(accel.samples[2].y);
             document.getElementById('accelerometer-z')!.innerText = normalize(accel.samples[2].z);
@@ -61,5 +61,6 @@ import { channelNames, EEGReading, MuseClient } from './../../src/muse';
         });
     } catch (err) {
         console.error('Connection failed', err);
+        document.getElementById('headset-name')!.innerText = 'Connection failed ' + err;
     }
 };
diff --git a/src/muse.ts b/src/muse.ts
index 3de6b54..82402f9 100644
--- a/src/muse.ts
+++ b/src/muse.ts
@@ -57,6 +57,9 @@ export class MuseClient {
         if (gatt) {
             this.gatt = gatt;
         } else {
+            if (!navigator.bluetooth) {
+                throw new Error('Bluetooth support required');
+            }
             const device = await navigator.bluetooth.requestDevice({
                 filters: [{ services: [MUSE_SERVICE] }],
             });
@@ -143,7 +146,12 @@ export class MuseClient {
     }
 
     async deviceInfo() {
-        const resultListener = this.controlResponses.pipe(filter((r) => !!r.fw), take(1)).toPromise();
+        const resultListener = this.controlResponses
+            .pipe(
+                filter((r) => !!r.fw),
+                take(1),
+            )
+            .toPromise();
         await this.sendCommand('v1');
         return resultListener as Promise<MuseDeviceInfo>;
     }