feat(notifications): add overlay notifications with position config (#110)

src/main/runtime/overlay-loading-osd-start.ts

@@ -0,0 +1,32 @@
+export function shouldStartOverlayLoadingOsd(args: {
+  visibleOverlayRequested: boolean;
+  overlayContentReady: boolean;
+  mediaPath?: string | null;
+}): boolean {
+  if (!args.visibleOverlayRequested || args.overlayContentReady) {
+    return false;
+  }
+  if (args.mediaPath !== undefined && (args.mediaPath ?? '').trim().length === 0) {
+    return false;
+  }
+  return true;
+}
+
+export function createMaybeStartOverlayLoadingOsdHandler(deps: {
+  getVisibleOverlayRequested: () => boolean;
+  isOverlayContentReady: () => boolean;
+  startOverlayLoadingOsd: () => void;
+}) {
+  return (mediaPath?: string | null): void => {
+    if (
+      !shouldStartOverlayLoadingOsd({
+        visibleOverlayRequested: deps.getVisibleOverlayRequested(),
+        overlayContentReady: deps.isOverlayContentReady(),
+        mediaPath,
+      })
+    ) {
+      return;
+    }
+    deps.startOverlayLoadingOsd();
+  };
+}