From b55aa0d2cb2ddda2a3f5ee411369dd142c8b3fb5 Mon Sep 17 00:00:00 2001
From: BFlat <bombayapirat@gmail.com>
Date: Tue, 18 Aug 2026 11:06:28 +0700
Subject: [PATCH] Add last viewed badge for previously viewed media (#1910)

for both desktop and webapp
---
 .../GenerationGalleryGrid.tsx                 | 14 +++++++----
 .../GenerationGalleryList.tsx                 | 14 +++++++----
 .../generation-gallery/useLightboxNav.ts      | 23 +++++++++++++------
 .../DesktopGenerationGallery.tsx              |  3 +++
 .../app/src/pages/PageAudio/CreateAudio.tsx   |  5 ++++
 .../app/src/pages/PageImage/TextToImage.tsx   |  5 ++++
 .../app/src/pages/PageVideo/ImageToVideo.tsx  |  5 ++++
 .../components/generation-list/src/index.ts   |  1 +
 .../generation-list/src/lib/GalleryCard.tsx   | 17 ++++++++++++--
 .../generation-list/src/lib/GalleryRow.tsx    | 15 ++++++++++--
 .../src/lib/GenerationGridView.tsx            |  4 ++++
 .../src/lib/GenerationListView.tsx            |  4 ++++
 .../src/lib/last-viewed-store.ts              | 20 ++++++++++++++++
 13 files changed, 109 insertions(+), 21 deletions(-)
 create mode 100644 frontend/libs/components/generation-list/src/lib/last-viewed-store.ts

diff --git a/frontend/apps/artcraft-webapp/src/components/generation-gallery/GenerationGalleryGrid.tsx b/frontend/apps/artcraft-webapp/src/components/generation-gallery/GenerationGalleryGrid.tsx
index 57d89f60e9..c3cdb8b3e5 100644
--- a/frontend/apps/artcraft-webapp/src/components/generation-gallery/GenerationGalleryGrid.tsx
+++ b/frontend/apps/artcraft-webapp/src/components/generation-gallery/GenerationGalleryGrid.tsx
@@ -4,9 +4,9 @@ import { Tooltip } from "@storyteller/ui-tooltip";
 import {
   GenerationGridView,
   type GalleryItem,
-  is3DMediaClass,
   type RecreateSlotContext,
   useGallerySelectionStore,
+  useLastViewedGenerationStore,
 } from "@storyteller/ui-generation-list";
 import { useRecreateFromPromptToken } from "../../lib/recreate";
 import { useGalleryItemActions } from "./useGalleryItemActions";
@@ -34,6 +34,7 @@ export function GenerationGalleryGrid({
 }: GenerationGalleryProps) {
   const selectionActive = useGallerySelectionStore((s) => s.active);
   const selectedIds = useGallerySelectionStore((s) => s.ids);
+  const lastViewedId = useLastViewedGenerationStore((s) => s.id);
   return (
     <GenerationGridView
       inProgressJobs={inProgressJobs}
@@ -54,6 +55,7 @@ export function GenerationGalleryGrid({
       selectionMode={!!selectable && selectionActive}
       selectedIds={selectedIds}
       onToggleSelect={handleToggleSelect}
+      lastViewedId={lastViewedId}
     />
   );
 }
@@ -70,14 +72,16 @@ function CardRecreateButton({
   mediaClass,
   kind,
 }: RecreateSlotContext) {
-  // Recreate only targets the image/video create pages; 3D generations have no
-  // recreate flow, so map to a valid class for the hook and render nothing.
+  // Recreate only targets the image/video create pages; 3D and audio
+  // generations have no recreate flow, so map to a valid class for the hook
+  // (it must run unconditionally) and render nothing.
+  const hasRecreateFlow = mediaClass === "image" || mediaClass === "video";
   const { isRecreating, handleRecreate } = useRecreateFromPromptToken(
     promptToken,
-    is3DMediaClass(mediaClass) ? "image" : mediaClass,
+    hasRecreateFlow ? mediaClass : "image",
   );
 
-  if (is3DMediaClass(mediaClass)) return null;
+  if (!hasRecreateFlow) return null;
 
   if (kind === "failed") {
     return (
diff --git a/frontend/apps/artcraft-webapp/src/components/generation-gallery/GenerationGalleryList.tsx b/frontend/apps/artcraft-webapp/src/components/generation-gallery/GenerationGalleryList.tsx
index 8dfc44a444..b90e0e8123 100644
--- a/frontend/apps/artcraft-webapp/src/components/generation-gallery/GenerationGalleryList.tsx
+++ b/frontend/apps/artcraft-webapp/src/components/generation-gallery/GenerationGalleryList.tsx
@@ -4,9 +4,9 @@ import { Tooltip } from "@storyteller/ui-tooltip";
 import {
   GenerationListView,
   type GalleryItem,
-  is3DMediaClass,
   type RecreateSlotContext,
   useGallerySelectionStore,
+  useLastViewedGenerationStore,
 } from "@storyteller/ui-generation-list";
 import { toast } from "../toast/toast";
 import { useRecreateFromPromptToken } from "../../lib/recreate";
@@ -38,6 +38,7 @@ export function GenerationGalleryList({
 }: GenerationGalleryProps) {
   const selectionActive = useGallerySelectionStore((s) => s.active);
   const selectedIds = useGallerySelectionStore((s) => s.ids);
+  const lastViewedId = useLastViewedGenerationStore((s) => s.id);
   return (
     <GenerationListView
       inProgressJobs={inProgressJobs}
@@ -63,6 +64,7 @@ export function GenerationGalleryList({
       selectionMode={!!selectable && selectionActive}
       selectedIds={selectedIds}
       onToggleSelect={handleToggleSelect}
+      lastViewedId={lastViewedId}
     />
   );
 }
@@ -86,14 +88,16 @@ function RowRecreateButton({
   mediaClass,
   kind,
 }: RecreateSlotContext) {
-  // Recreate only targets the image/video create pages; 3D generations have no
-  // recreate flow, so map to a valid class for the hook and render nothing.
+  // Recreate only targets the image/video create pages; 3D and audio
+  // generations have no recreate flow, so map to a valid class for the hook
+  // (it must run unconditionally) and render nothing.
+  const hasRecreateFlow = mediaClass === "image" || mediaClass === "video";
   const { isRecreating, handleRecreate } = useRecreateFromPromptToken(
     promptToken,
-    is3DMediaClass(mediaClass) ? "image" : mediaClass,
+    hasRecreateFlow ? mediaClass : "image",
   );
 
-  if (is3DMediaClass(mediaClass)) return null;
+  if (!hasRecreateFlow) return null;
   return (
     <Tooltip content="Recreate" position="top">
       <button
diff --git a/frontend/apps/artcraft-webapp/src/components/generation-gallery/useLightboxNav.ts b/frontend/apps/artcraft-webapp/src/components/generation-gallery/useLightboxNav.ts
index b5e145e619..70a54e17d9 100644
--- a/frontend/apps/artcraft-webapp/src/components/generation-gallery/useLightboxNav.ts
+++ b/frontend/apps/artcraft-webapp/src/components/generation-gallery/useLightboxNav.ts
@@ -1,15 +1,26 @@
-import { useCallback, useMemo, useState } from "react";
+import { useCallback, useState } from "react";
+import { useLastViewedGenerationStore } from "@storyteller/ui-generation-list";
 import type { GalleryItem } from "./useGalleryData";
 
 export function useLightboxNav(flatItems: GalleryItem[]) {
   const [lightboxOpen, setLightboxOpen] = useState(false);
   const [lightboxItem, setLightboxItem] = useState<GalleryItem | null>(null);
 
-  const handleGalleryItemClick = useCallback((item: GalleryItem) => {
+  // Every lightbox show (open and prev/next) moves the "Last viewed" marker
+  // so the feed can badge that tile after the lightbox closes.
+  const showItem = useCallback((item: GalleryItem) => {
+    useLastViewedGenerationStore.getState().setId(item.id);
     setLightboxItem(item);
-    setLightboxOpen(true);
   }, []);
 
+  const handleGalleryItemClick = useCallback(
+    (item: GalleryItem) => {
+      showItem(item);
+      setLightboxOpen(true);
+    },
+    [showItem],
+  );
+
   const closeLightbox = useCallback(() => {
     setLightboxOpen(false);
     setLightboxItem(null);
@@ -20,13 +31,11 @@ export function useLightboxNav(flatItems: GalleryItem[]) {
     : -1;
 
   const navigatePrev =
-    currentIndex > 0
-      ? () => setLightboxItem(flatItems[currentIndex - 1])
-      : undefined;
+    currentIndex > 0 ? () => showItem(flatItems[currentIndex - 1]) : undefined;
 
   const navigateNext =
     currentIndex >= 0 && currentIndex < flatItems.length - 1
-      ? () => setLightboxItem(flatItems[currentIndex + 1])
+      ? () => showItem(flatItems[currentIndex + 1])
       : undefined;
 
   return {
diff --git a/frontend/apps/artcraft/app/src/components/generation-feed/DesktopGenerationGallery.tsx b/frontend/apps/artcraft/app/src/components/generation-feed/DesktopGenerationGallery.tsx
index 4f0f660f35..fbfa3a9b71 100644
--- a/frontend/apps/artcraft/app/src/components/generation-feed/DesktopGenerationGallery.tsx
+++ b/frontend/apps/artcraft/app/src/components/generation-feed/DesktopGenerationGallery.tsx
@@ -38,6 +38,9 @@ export interface DesktopGenerationGalleryProps {
   isInitialLoading: boolean;
   onLoadMore: () => void;
   onGalleryItemClick: (item: GalleryItem) => void;
+  /** Id of the item most recently viewed in the lightbox; that tile gets a
+   *  persistent "Last viewed" badge. */
+  lastViewedId?: string | null;
   /** Image page only: show a "Make Video" quick action on image items. */
   enableMakeVideo?: boolean;
   /** Enables the multi-select + batch download flow (select toggle in the
diff --git a/frontend/apps/artcraft/app/src/pages/PageAudio/CreateAudio.tsx b/frontend/apps/artcraft/app/src/pages/PageAudio/CreateAudio.tsx
index 028a361c16..da5f772252 100644
--- a/frontend/apps/artcraft/app/src/pages/PageAudio/CreateAudio.tsx
+++ b/frontend/apps/artcraft/app/src/pages/PageAudio/CreateAudio.tsx
@@ -18,6 +18,7 @@ import { HelpMenuButton } from "@storyteller/ui-help-menu";
 import {
   useGalleryData,
   useGenerationJobs,
+  useLastViewedGenerationStore,
   type GalleryItem,
 } from "@storyteller/ui-generation-list";
 import { useDesktopUsername } from "~/components/generation-feed/useDesktopUsername";
@@ -115,7 +116,10 @@ const CreateAudio = () => {
 
   // Open a completed row in the global lightbox (rendered by TopBar's
   // gallery modal); prev/next walk the merged feed order.
+  const lastViewedId = useLastViewedGenerationStore((s) => s.id);
+
   const openInLightbox = useCallback((item: GalleryItem) => {
+    useLastViewedGenerationStore.getState().setId(item.id);
     const list = flatCompletedRef.current;
     const index = list.findIndex((i) => i.id === item.id);
     galleryModalLightboxNavPrev.value =
@@ -156,6 +160,7 @@ const CreateAudio = () => {
           isInitialLoading={gallery.isInitialLoading}
           onLoadMore={gallery.loadMore}
           onGalleryItemClick={openInLightbox}
+          lastViewedId={lastViewedId}
         />
       }
       promptBox={
diff --git a/frontend/apps/artcraft/app/src/pages/PageImage/TextToImage.tsx b/frontend/apps/artcraft/app/src/pages/PageImage/TextToImage.tsx
index b65c88ab25..435c110f11 100644
--- a/frontend/apps/artcraft/app/src/pages/PageImage/TextToImage.tsx
+++ b/frontend/apps/artcraft/app/src/pages/PageImage/TextToImage.tsx
@@ -27,6 +27,7 @@ import {
 import { GenerationProvider } from "@storyteller/api-enums";
 import {
   useGalleryData,
+  useLastViewedGenerationStore,
   type GalleryItem,
 } from "@storyteller/ui-generation-list";
 import { useDesktopGenerationFeed } from "~/components/generation-feed/useDesktopGenerationFeed";
@@ -128,7 +129,10 @@ const TextToImage = ({ imageMediaId, imageUrl }: TextToImageProps) => {
 
   // Open a completed row in the global lightbox (rendered by TopBar's
   // gallery modal); prev/next walk the merged feed order.
+  const lastViewedId = useLastViewedGenerationStore((s) => s.id);
+
   const openInLightbox = useCallback((item: GalleryItem) => {
+    useLastViewedGenerationStore.getState().setId(item.id);
     const list = flatCompletedRef.current;
     const index = list.findIndex((i) => i.id === item.id);
     galleryModalLightboxNavPrev.value =
@@ -169,6 +173,7 @@ const TextToImage = ({ imageMediaId, imageUrl }: TextToImageProps) => {
           isInitialLoading={gallery.isInitialLoading}
           onLoadMore={gallery.loadMore}
           onGalleryItemClick={openInLightbox}
+          lastViewedId={lastViewedId}
           enableMakeVideo
           selectable
           selectionBarBottomOffset={promptHeight + 32}
diff --git a/frontend/apps/artcraft/app/src/pages/PageVideo/ImageToVideo.tsx b/frontend/apps/artcraft/app/src/pages/PageVideo/ImageToVideo.tsx
index 578a31b64e..c4ae011265 100644
--- a/frontend/apps/artcraft/app/src/pages/PageVideo/ImageToVideo.tsx
+++ b/frontend/apps/artcraft/app/src/pages/PageVideo/ImageToVideo.tsx
@@ -39,6 +39,7 @@ import {
 import { GenerationProvider } from "@storyteller/api-enums";
 import {
   useGalleryData,
+  useLastViewedGenerationStore,
   type GalleryItem,
 } from "@storyteller/ui-generation-list";
 import { useDesktopGenerationFeed } from "~/components/generation-feed/useDesktopGenerationFeed";
@@ -156,7 +157,10 @@ const ImageToVideo = ({ imageMediaId, imageUrl }: ImageToVideoProps) => {
 
   // Open a completed row in the global lightbox (rendered by TopBar's
   // gallery modal); prev/next walk the merged feed order.
+  const lastViewedId = useLastViewedGenerationStore((s) => s.id);
+
   const openInLightbox = useCallback((item: GalleryItem) => {
+    useLastViewedGenerationStore.getState().setId(item.id);
     const list = flatCompletedRef.current;
     const index = list.findIndex((i) => i.id === item.id);
     galleryModalLightboxNavPrev.value =
@@ -197,6 +201,7 @@ const ImageToVideo = ({ imageMediaId, imageUrl }: ImageToVideoProps) => {
           isInitialLoading={gallery.isInitialLoading}
           onLoadMore={gallery.loadMore}
           onGalleryItemClick={openInLightbox}
+          lastViewedId={lastViewedId}
           selectable
           selectionBarBottomOffset={promptHeight + 32}
         />
diff --git a/frontend/libs/components/generation-list/src/index.ts b/frontend/libs/components/generation-list/src/index.ts
index f54cadcdcd..5ebf8e63f7 100644
--- a/frontend/libs/components/generation-list/src/index.ts
+++ b/frontend/libs/components/generation-list/src/index.ts
@@ -5,6 +5,7 @@ export * from "./lib/prompts-cache";
 export * from "./lib/media-prompt-token-cache";
 export * from "./lib/gallery-view-store";
 export * from "./lib/gallery-selection-store";
+export * from "./lib/last-viewed-store";
 export * from "./lib/GalleryViewToggle";
 export * from "./lib/GalleryAutoplayToggle";
 export * from "./lib/GallerySelectToggle";
diff --git a/frontend/libs/components/generation-list/src/lib/GalleryCard.tsx b/frontend/libs/components/generation-list/src/lib/GalleryCard.tsx
index 3f8e94aca5..0929c1453e 100644
--- a/frontend/libs/components/generation-list/src/lib/GalleryCard.tsx
+++ b/frontend/libs/components/generation-list/src/lib/GalleryCard.tsx
@@ -1,5 +1,5 @@
 import { memo, useCallback, useState, type ReactNode } from "react";
-import { BoxIcon, CheckIcon, ImageIcon, MusicIcon, VideoIcon } from "lucide-react";
+import { BoxIcon, CheckIcon, EyeIcon, ImageIcon, MusicIcon, VideoIcon } from "lucide-react";
 import { DynamicIcon } from "@storyteller/icons";
 import {
   getCreatorIconPathForModelId,
@@ -73,6 +73,8 @@ export interface GalleryCardProps {
   selectMode?: boolean;
   selected?: boolean;
   onToggleSelect?: (item: GalleryItem) => void;
+  /** Persistent badge marking the item most recently viewed in the lightbox. */
+  lastViewed?: boolean;
 }
 
 export const GalleryCard = memo(function GalleryCard({
@@ -84,6 +86,7 @@ export const GalleryCard = memo(function GalleryCard({
   selectMode = false,
   selected = false,
   onToggleSelect,
+  lastViewed = false,
 }: GalleryCardProps) {
   const isSquare = shape === "square";
   const cached = aspectRatioCache.get(item.id);
@@ -162,7 +165,7 @@ export const GalleryCard = memo(function GalleryCard({
     <div
       role="button"
       tabIndex={0}
-      className={`group relative block w-full rounded-lg bg-ui-controls/40 leading-none transition-shadow hover:ring-2 hover:ring-primary-400/60 focus:outline-none focus-visible:ring-2 focus-visible:ring-primary-400 cursor-pointer ${isSquare ? "aspect-square" : ""} ${selected ? "ring-2 ring-primary-400" : ""}`}
+      className={`group relative block w-full rounded-lg bg-ui-controls/40 leading-none transition-shadow hover:ring-2 hover:ring-primary-400/60 focus:outline-none focus-visible:ring-2 focus-visible:ring-primary-400 cursor-pointer ${isSquare ? "aspect-square" : ""} ${selected ? "ring-2 ring-primary-400" : lastViewed ? "ring-2 ring-primary-400/50" : ""}`}
       style={outerStyle}
       onClick={handleCardClick}
       onKeyDown={handleCardKeyDown}
@@ -223,6 +226,16 @@ export const GalleryCard = memo(function GalleryCard({
         </div>
       )}
 
+      {/* Persistent "Last viewed" badge (stays until another item is opened
+          in the lightbox). Top-right so it never collides with the selection
+          checkbox chip at top-left. */}
+      {lastViewed && (
+        <div className="pointer-events-none absolute right-2 top-2 z-10 flex items-center gap-1 rounded-full bg-black/70 px-2 py-0.5 text-[10px] font-medium uppercase tracking-wide text-white/80">
+          <EyeIcon />
+          Last viewed
+        </div>
+      )}
+
       {/* Hover overlay with media type + model badges and quick actions */}
       <div className="pointer-events-none absolute inset-x-0 bottom-0 flex items-end justify-between gap-2 bg-gradient-to-t rounded-b-lg from-black/70 to-transparent px-2 pb-2 pt-6 opacity-0 transition-opacity group-hover:opacity-100">
         <div className="pointer-events-auto flex min-w-0 flex-wrap items-center gap-1.5">
diff --git a/frontend/libs/components/generation-list/src/lib/GalleryRow.tsx b/frontend/libs/components/generation-list/src/lib/GalleryRow.tsx
index f01fd20980..cbfb65a63c 100644
--- a/frontend/libs/components/generation-list/src/lib/GalleryRow.tsx
+++ b/frontend/libs/components/generation-list/src/lib/GalleryRow.tsx
@@ -1,5 +1,5 @@
 import { memo, useCallback, type ReactNode } from "react";
-import { BoxIcon, CheckIcon, ImageIcon, MusicIcon, PlayIcon, VideoIcon } from "lucide-react";
+import { BoxIcon, CheckIcon, EyeIcon, ImageIcon, MusicIcon, PlayIcon, VideoIcon } from "lucide-react";
 import {
   getCreatorIconPathForModelId,
   getModelDisplayName,
@@ -27,6 +27,8 @@ export interface GalleryRowProps {
   selectMode?: boolean;
   selected?: boolean;
   onToggleSelect?: (item: GalleryItem) => void;
+  /** Persistent badge marking the item most recently viewed in the lightbox. */
+  lastViewed?: boolean;
 }
 
 export const GalleryRow = memo(function GalleryRow({
@@ -40,6 +42,7 @@ export const GalleryRow = memo(function GalleryRow({
   selectMode = false,
   selected = false,
   onToggleSelect,
+  lastViewed = false,
 }: GalleryRowProps) {
   const isVideo = item.mediaClass === "video";
   const is3D = is3DMediaClass(item.mediaClass);
@@ -103,7 +106,7 @@ export const GalleryRow = memo(function GalleryRow({
       )}
 
       {/* Thumbnail */}
-      <div className="relative size-[100px] shrink-0 overflow-hidden rounded-md bg-ui-controls/40 leading-none">
+      <div className={`relative size-[100px] shrink-0 overflow-hidden rounded-md bg-ui-controls/40 leading-none ${lastViewed ? "ring-2 ring-primary-400/50" : ""}`}>
         <GalleryThumbnail
           thumbnail={item.thumbnail}
           stillThumbnail={item.stillThumbnail}
@@ -122,6 +125,14 @@ export const GalleryRow = memo(function GalleryRow({
             </span>
           </div>
         )}
+        {/* Persistent "Last viewed" badge (stays until another item is
+            opened in the lightbox). */}
+        {lastViewed && (
+          <div className="pointer-events-none absolute left-1 top-1 z-10 flex items-center gap-1 rounded-full bg-black/70 px-1.5 py-0.5 text-[9px] font-medium uppercase tracking-wide text-white/80">
+            <EyeIcon />
+            Last viewed
+          </div>
+        )}
       </div>
 
       {/* Title + model / media meta */}
diff --git a/frontend/libs/components/generation-list/src/lib/GenerationGridView.tsx b/frontend/libs/components/generation-list/src/lib/GenerationGridView.tsx
index fc1e2e144a..712f4735e4 100644
--- a/frontend/libs/components/generation-list/src/lib/GenerationGridView.tsx
+++ b/frontend/libs/components/generation-list/src/lib/GenerationGridView.tsx
@@ -53,6 +53,8 @@ export interface GenerationGridViewProps {
   selectionMode?: boolean;
   selectedIds?: ReadonlySet<string>;
   onToggleSelect?: (item: GalleryItem) => void;
+  /** Marks the tile the user most recently viewed in the lightbox. */
+  lastViewedId?: string | null;
 }
 
 export function GenerationGridView({
@@ -71,6 +73,7 @@ export function GenerationGridView({
   selectionMode = false,
   selectedIds,
   onToggleSelect,
+  lastViewedId,
 }: GenerationGridViewProps) {
   const sentinelRef = useInfiniteScrollSentinel(hasMore, onLoadMore);
 
@@ -198,6 +201,7 @@ export function GenerationGridView({
                 selectMode={selectionMode}
                 selected={selectionMode && selectedIds?.has(entry.item.id)}
                 onToggleSelect={onToggleSelect}
+                lastViewed={!!lastViewedId && entry.item.id === lastViewedId}
               />
             )}
           </div>
diff --git a/frontend/libs/components/generation-list/src/lib/GenerationListView.tsx b/frontend/libs/components/generation-list/src/lib/GenerationListView.tsx
index ff155b6def..8ea889c6ad 100644
--- a/frontend/libs/components/generation-list/src/lib/GenerationListView.tsx
+++ b/frontend/libs/components/generation-list/src/lib/GenerationListView.tsx
@@ -56,6 +56,8 @@ export interface GenerationListViewProps {
   selectionMode?: boolean;
   selectedIds?: ReadonlySet<string>;
   onToggleSelect?: (item: GalleryItem) => void;
+  /** Marks the row the user most recently viewed in the lightbox. */
+  lastViewedId?: string | null;
 }
 
 export function GenerationListView({
@@ -75,6 +77,7 @@ export function GenerationListView({
   selectionMode = false,
   selectedIds,
   onToggleSelect,
+  lastViewedId,
 }: GenerationListViewProps) {
   const sentinelRef = useInfiniteScrollSentinel(hasMore, onLoadMore);
 
@@ -211,6 +214,7 @@ export function GenerationListView({
               selectMode={selectionMode}
               selected={selectionMode && selectedIds?.has(entry.item.id)}
               onToggleSelect={onToggleSelect}
+              lastViewed={!!lastViewedId && entry.item.id === lastViewedId}
             />
           );
         })}
diff --git a/frontend/libs/components/generation-list/src/lib/last-viewed-store.ts b/frontend/libs/components/generation-list/src/lib/last-viewed-store.ts
new file mode 100644
index 0000000000..9486ba0d5f
--- /dev/null
+++ b/frontend/libs/components/generation-list/src/lib/last-viewed-store.ts
@@ -0,0 +1,20 @@
+import { create } from "zustand";
+
+// Remembers the generation most recently viewed in a lightbox opened from a
+// create-page feed, so the feed can badge that tile after the lightbox
+// closes. Set on every lightbox show (prev/next included). Module-level so it
+// survives page remounts (tab switch, route change); in-memory only.
+// Lightboxes opened elsewhere (library, task queue) intentionally do not move
+// the marker.
+
+interface LastViewedGenerationState {
+  id: string | null;
+  setId: (id: string) => void;
+}
+
+export const useLastViewedGenerationStore = create<LastViewedGenerationState>(
+  (set) => ({
+    id: null,
+    setId: (id) => set({ id }),
+  }),
+);