Detect webcams unplugged

front/src/Stores/MediaStore.ts

@@ -209,10 +209,14 @@ function createVideoConstraintStore() {
 
     return {
         subscribe,
-        setDeviceId: (deviceId: string) => update((constraints) => {
+        setDeviceId: (deviceId: string|undefined) => update((constraints) => {
+            if (deviceId !== undefined) {
                 constraints.deviceId = {
                     exact: deviceId
                 };
+            } else {
+                delete constraints.deviceId;
+            }
 
             return constraints;
         }),
@@ -241,15 +245,19 @@ function createAudioConstraintStore() {
 
     return {
         subscribe,
-        setDeviceId: (deviceId: string) => update((constraints) => {
+        setDeviceId: (deviceId: string|undefined) => update((constraints) => {
             selectedDeviceId = deviceId;
 
             if (typeof(constraints) === 'boolean') {
                 constraints = {}
             }
+            if (deviceId !== undefined) {
                 constraints.deviceId = {
                     exact: selectedDeviceId
                 };
+            } else {
+                delete constraints.deviceId;
+            }
 
             return constraints;
         })
@@ -552,3 +560,35 @@ export const cameraListStore = derived(deviceListStore, ($deviceListStore) => {
 export const microphoneListStore = derived(deviceListStore, ($deviceListStore) => {
     return $deviceListStore.filter(device => device.kind === 'audioinput');
 });
+
+// TODO: detect the new webcam and automatically switch on it.
+cameraListStore.subscribe((devices) => {
+    // If the selected camera is unplugged, let's remove the constraint on deviceId
+    const constraints = get(videoConstraintStore);
+    if (!constraints.deviceId) {
+        return;
+    }
+
+    // If we cannot find the device ID, let's remove it.
+    // @ts-ignore
+    if (!devices.find(device => device.deviceId === constraints.deviceId.exact)) {
+        videoConstraintStore.setDeviceId(undefined);
+    }
+});
+
+microphoneListStore.subscribe((devices) => {
+    // If the selected camera is unplugged, let's remove the constraint on deviceId
+    const constraints = get(audioConstraintStore);
+    if (typeof constraints === 'boolean') {
+        return;
+    }
+    if (!constraints.deviceId) {
+        return;
+    }
+
+    // If we cannot find the device ID, let's remove it.
+    // @ts-ignore
+    if (!devices.find(device => device.deviceId === constraints.deviceId.exact)) {
+        audioConstraintStore.setDeviceId(undefined);
+    }
+});