Fix duplicate QR scanner initialization on page navigation

.gitignore

@@ -7,3 +7,8 @@ src/*.d.ts
 src/*/*.d.ts
 src/*/*/*.d.ts
 docs/
+output/
+lib/
+build/
+meta/
+.rpt2_cache

output/tests/src/camera/core-impl.d.ts

@@ -0,0 +1,7 @@
+import { Camera, CameraRenderingOptions, RenderedCamera, RenderingCallbacks } from "./core";
+export declare class CameraImpl implements Camera {
+    private readonly mediaStream;
+    private constructor();
+    render(parentElement: HTMLElement, options: CameraRenderingOptions, callbacks: RenderingCallbacks): Promise<RenderedCamera>;
+    static create(videoConstraints: MediaTrackConstraints): Promise<Camera>;
+}

output/tests/src/camera/core.d.ts

@@ -0,0 +1,41 @@
+export interface CameraDevice {
+    id: string;
+    label: string;
+}
+export interface CameraCapability<T> {
+    isSupported(): boolean;
+    apply(value: T): Promise<void>;
+    value(): T | null;
+}
+export interface RangeCameraCapability extends CameraCapability<number> {
+    min(): number;
+    max(): number;
+    step(): number;
+}
+export interface BooleanCameraCapability extends CameraCapability<boolean> {
+}
+export interface CameraCapabilities {
+    zoomFeature(): RangeCameraCapability;
+    torchFeature(): BooleanCameraCapability;
+}
+export type OnRenderSurfaceReady = (viewfinderWidth: number, viewfinderHeight: number) => void;
+export interface RenderingCallbacks {
+    onRenderSurfaceReady: OnRenderSurfaceReady;
+}
+export interface RenderedCamera {
+    getSurface(): HTMLVideoElement;
+    pause(): void;
+    resume(onResumeCallback: () => void): void;
+    isPaused(): boolean;
+    close(): Promise<void>;
+    getRunningTrackCapabilities(): MediaTrackCapabilities;
+    getRunningTrackSettings(): MediaTrackSettings;
+    applyVideoConstraints(constraints: MediaTrackConstraints): Promise<void>;
+    getCapabilities(): CameraCapabilities;
+}
+export interface CameraRenderingOptions {
+    aspectRatio?: number;
+}
+export interface Camera {
+    render(parentElement: HTMLElement, options: CameraRenderingOptions, callbacks: RenderingCallbacks): Promise<RenderedCamera>;
+}

output/tests/src/camera/factories.d.ts

@@ -0,0 +1,6 @@
+import { Camera } from "./core";
+export declare class CameraFactory {
+    static failIfNotSupported(): Promise<CameraFactory>;
+    private constructor();
+    create(videoConstraints: MediaTrackConstraints): Promise<Camera>;
+}

output/tests/src/camera/permissions.d.ts

@@ -0,0 +1,3 @@
+export declare class CameraPermissions {
+    static hasPermissions(): Promise<boolean>;
+}