refactor: extract canvas derived state

src/features/canvas/CanvasPage.tsx

@@ -55,6 +55,7 @@ import { useCanvasHistory, type CanvasHistorySnapshot } from "./useCanvasHistory
 import { useCanvasKeyboard } from "./useCanvasKeyboard";
 import { useCanvasNodeDrag } from "./useCanvasNodeDrag";
 import { useCanvasGeneration, addCanvasGenKeepalive, removeCanvasGenKeepalive } from "./useCanvasGeneration";
+import { useCanvasAssetSummary, useCanvasVisibleNodes } from "./useCanvasDerivedState";
 import {
   toHappyHorseDisplayModel,
 } from "../../utils/happyHorseRouting";
@@ -578,17 +579,7 @@ function CanvasPage({
   // Save immediately when user leaves page or switches tab (placed after runCanvasAutoSave definition)
   // — see useEffect below near runCanvasAutoSave
 
-  const canvasAssets = useMemo(
+  const { canvasAssets, assetCountsByCategory } = useCanvasAssetSummary(serverAssets);
-    () => serverAssets.filter((asset) => asset.imageUrl),
-    [serverAssets],
-  );
-  const assetCountsByCategory = useMemo(() => {
-    const counts = new Map<string, number>();
-    for (const asset of serverAssets) {
-      counts.set(asset.type, (counts.get(asset.type) ?? 0) + 1);
-    }
-    return counts;
-  }, [serverAssets]);
   const shouldShowEmptyProjectState =
     projectsLoaded && projects.length === 0 && !projectId && workflow.source === "blank" && workflow.nodes.length === 0;
   const isWaitingForProjects = isAuthenticated && !projectsLoaded;
@@ -2650,16 +2641,17 @@ function CanvasPage({
     setConnectorDrag(null);
   };
 
-  const collapsedPackageNodeKeys = useMemo(
+  const {
-    () => new Set(
+    isNodeCollapsedInPackage,
-      nodePackages.flatMap((nodePackage) =>
+    visibleTextNodes,
-        nodePackage.collapsed ? nodePackage.nodeIds.map((node) => getCanvasSelectionKey(node)) : []
+    visibleImageNodes,
-      )
+    visibleVideoNodes,
-    ),
+  } = useCanvasVisibleNodes({
-    [nodePackages],
+    textNodes,
-  );
+    imageNodes,
-  const isNodeCollapsedInPackage = (kind: CanvasNodeKind, id: string) =>
+    videoNodes,
-    collapsedPackageNodeKeys.has(getCanvasSelectionKey({ kind, id }));
+    nodePackages,
+  });
   const isLinkCollapsedInPackage = (link: { sourceKind: CanvasNodeKind; sourceNodeId: string; targetKind: CanvasNodeKind; targetNodeId: string }) =>
     isNodeCollapsedInPackage(link.sourceKind, link.sourceNodeId) ||
     isNodeCollapsedInPackage(link.targetKind, link.targetNodeId);
@@ -2697,18 +2689,6 @@ function CanvasPage({
       return positionedLink ? [positionedLink] : [];
     }),
   ].filter((link) => !isLinkCollapsedInPackage(link));
-  const visibleTextNodes = useMemo(
-    () => textNodes.filter((textNode) => !isNodeCollapsedInPackage("text", textNode.id)),
-    [collapsedPackageNodeKeys, textNodes],
-  );
-  const visibleImageNodes = useMemo(
-    () => imageNodes.filter((imageNode) => !isNodeCollapsedInPackage("image", imageNode.id)),
-    [collapsedPackageNodeKeys, imageNodes],
-  );
-  const visibleVideoNodes = useMemo(
-    () => videoNodes.filter((videoNode) => !isNodeCollapsedInPackage("video", videoNode.id)),
-    [collapsedPackageNodeKeys, videoNodes],
-  );
   const pendingLinkPreview =
     pendingLinkPort && pendingLinkPreviewPoint
       ? (() => {

src/features/canvas/useCanvasDerivedState.ts

@@ -0,0 +1,74 @@
+import { useCallback, useMemo } from "react";
+import type { ServerAssetItem } from "../../api/assetClient";
+import type {
+  CanvasImageNode,
+  CanvasNodeKind,
+  CanvasNodePackage,
+  CanvasTextNode,
+  CanvasVideoNode,
+} from "./canvasTypes";
+import { getCanvasSelectionKey } from "./canvasUtils";
+
+export function useCanvasAssetSummary(serverAssets: ServerAssetItem[]) {
+  return useMemo(() => {
+    const canvasAssets: ServerAssetItem[] = [];
+    const assetCountsByCategory = new Map<string, number>();
+
+    for (const asset of serverAssets) {
+      if (asset.imageUrl) {
+        canvasAssets.push(asset);
+      }
+      assetCountsByCategory.set(asset.type, (assetCountsByCategory.get(asset.type) ?? 0) + 1);
+    }
+
+    return { canvasAssets, assetCountsByCategory };
+  }, [serverAssets]);
+}
+
+export function useCanvasVisibleNodes({
+  textNodes,
+  imageNodes,
+  videoNodes,
+  nodePackages,
+}: {
+  textNodes: CanvasTextNode[];
+  imageNodes: CanvasImageNode[];
+  videoNodes: CanvasVideoNode[];
+  nodePackages: CanvasNodePackage[];
+}) {
+  const collapsedPackageNodeKeys = useMemo(
+    () => new Set(
+      nodePackages.flatMap((nodePackage) =>
+        nodePackage.collapsed ? nodePackage.nodeIds.map((node) => getCanvasSelectionKey(node)) : []
+      )
+    ),
+    [nodePackages],
+  );
+
+  const isNodeCollapsedInPackage = useCallback(
+    (kind: CanvasNodeKind, id: string) =>
+      collapsedPackageNodeKeys.has(getCanvasSelectionKey({ kind, id })),
+    [collapsedPackageNodeKeys],
+  );
+
+  const visibleTextNodes = useMemo(
+    () => textNodes.filter((textNode) => !collapsedPackageNodeKeys.has(getCanvasSelectionKey({ kind: "text", id: textNode.id }))),
+    [collapsedPackageNodeKeys, textNodes],
+  );
+  const visibleImageNodes = useMemo(
+    () => imageNodes.filter((imageNode) => !collapsedPackageNodeKeys.has(getCanvasSelectionKey({ kind: "image", id: imageNode.id }))),
+    [collapsedPackageNodeKeys, imageNodes],
+  );
+  const visibleVideoNodes = useMemo(
+    () => videoNodes.filter((videoNode) => !collapsedPackageNodeKeys.has(getCanvasSelectionKey({ kind: "video", id: videoNode.id }))),
+    [collapsedPackageNodeKeys, videoNodes],
+  );
+
+  return {
+    collapsedPackageNodeKeys,
+    isNodeCollapsedInPackage,
+    visibleTextNodes,
+    visibleImageNodes,
+    visibleVideoNodes,
+  };
+}