1 files changed, 56 insertions, 0 deletions
diff --git a/src/utils/shelves.ts b/src/utils/shelves.ts
new file mode 100644
index 0000000..e144f4b
--- /dev/null
+++ b/src/utils/shelves.ts
@@ -0,0 +1,56 @@
+import type {
+    ShelfBasedProductPage,
+    Shelf,
+} from '@jet-app/app-store/api/models';
+import { isProductMediaShelf } from '~/components/jet/shelf/ProductMediaShelf.svelte';
+
+type ShelfWithExpandedMedia = Shelf & {
+    expandedMedia?: ShelfWithExpandedMedia[];
+};
+
+export const getProductPageShelvesForOrdering = (
+    page: ShelfBasedProductPage,
+    shelfOrder: string,
+): Shelf[] => {
+    return (
+        page.shelfOrderings[shelfOrder]
+            ?.map((shelfIdentifier) => page.shelfMapping[shelfIdentifier])
+            // The type system doesn't reflect this, but ordering identifier may be provided for
+            // shelves that do not exist. We should probably filter those out
+            .filter((shelf): shelf is Shelf => !!shelf)
+    );
+};
+
+export const getProductPageShelvesWithExpandedMedia = (
+    page: ShelfBasedProductPage,
+): ShelfWithExpandedMedia[] => {
+    const { defaultShelfOrdering = 'notPurchasedOrdering' } = page;
+
+    const shelves = getProductPageShelvesForOrdering(
+        page,
+        defaultShelfOrdering,
+    ) as ShelfWithExpandedMedia[];
+
+    // find the location of the product media of selected platform in shelves
+    const mainMediaShelfIndex = shelves.findIndex((shelf) =>
+        isProductMediaShelf(shelf),
+    );
+
+    let expandedMedia: ShelfWithExpandedMedia[] | undefined;
+
+    if (mainMediaShelfIndex !== -1) {
+        expandedMedia = getProductPageShelvesForOrdering(
+            page,
+            'notPurchasedOrdering_ExpandedMedia',
+        )
+            .filter((shelf) => isProductMediaShelf(shelf))
+            // filter out the product media shelf of selected platform to avoid duplicate shelves
+            .filter(({ id }) => id !== shelves[mainMediaShelfIndex].id);
+    }
+
+    if (expandedMedia) {
+        shelves[mainMediaShelfIndex].expandedMedia = expandedMedia;
+    }
+
+    return shelves;
+};