no prev/next anymore

frontend/src/hooks/useAssetNavigator.ts

@@ -1,28 +1,26 @@
-import { useCallback, useEffect, useMemo, useState } from 'react';
+import { useEffect, useMemo, useState } from 'react';
 import { createAssetView } from '../asset_manager';
 
 type Identifier = string | number;
 
-interface DocumentLike {
+type DocumentLike = {
   id?: Identifier;
   [key: string]: unknown;
-}
+};
 
-interface AssetObject {
-  ordinal?: number;
+type AssetObject = {
   url?: string | null;
   metadata?: Record<string, unknown> | null;
   [key: string]: unknown;
-}
+};
 
-interface AssetLike {
+type AssetLike = {
   id?: Identifier;
-  cardinality?: number;
   url?: string | null;
   metadata?: Record<string, unknown> | null;
   objects?: AssetObject[];
   [key: string]: unknown;
-}
+};
 
 type EnsureAssetUrl = (
   documentId: Identifier,
@@ -32,21 +30,18 @@ type EnsureAssetUrl = (
 
 type GetAsset = (document: DocumentLike, assetType: string) => AssetLike | null;
 
-interface AssetViewLike {
-  getCardinality: () => number;
-  getObjects: () => AssetObject[];
+type AssetViewLike = {
   getObject: (ordinal?: number) => AssetObject | null;
+  getObjects: () => AssetObject[];
   getPrimaryUrl: () => string | null;
   getPrimaryMetadata: () => Record<string, unknown> | null;
-}
+};
 
 interface UseAssetNavigatorOptions {
   document?: DocumentLike | null;
   assetType: string;
-  ensureAssetUrl?: EnsureAssetUrl;
+  ensureAssetUrl?: EnsureAssetUrl | null;
   getAsset?: GetAsset;
-  prefetch?: number;
-  defaultOrdinal?: number;
 }
 
 interface AssetNavigatorReturn {
@@ -54,36 +49,16 @@ interface AssetNavigatorReturn {
   documentId: Identifier | null;
   asset: AssetLike | null;
   assetType: string;
-  ordinal: number;
-  setOrdinal: (next: number) => void;
-  goPrev: () => void;
-  goNext: () => void;
-  canGoPrev: boolean;
-  canGoNext: boolean;
-  cardinality: number;
-  currentObject: AssetObject | null;
   currentUrl: string | null;
-  currentMetadata: AssetObject['metadata'];
-  objects: AssetObject[];
+  currentMetadata: Record<string, unknown> | null;
   isLoading: boolean;
 }
 
-const clampOrdinalValue = (value: number, cardinality: number, defaultOrdinal: number) => {
-  const raw = Number.isFinite(value) ? value : defaultOrdinal;
-  let next = Math.max(1, Math.floor(raw));
-  if (cardinality && cardinality > 0) {
-    next = Math.min(next, cardinality);
-  }
-  return next;
-};
-
 export const useAssetNavigator = ({
   document,
   assetType,
   ensureAssetUrl,
   getAsset,
-  prefetch = 2,
-  defaultOrdinal = 1,
 }: UseAssetNavigatorOptions): AssetNavigatorReturn => {
   const documentId = (document?.id ?? null) as Identifier | null;
 
@@ -98,110 +73,42 @@ export const useAssetNavigator = ({
     () => createAssetView(asset) as unknown as AssetViewLike,
     [asset],
   );
-  const cardinality = view.getCardinality();
 
-  const [ordinal, setOrdinalInternal] = useState(defaultOrdinal);
-
-  useEffect(() => {
-    setOrdinalInternal(defaultOrdinal);
-  }, [documentId, assetType, defaultOrdinal]);
-
-  const setOrdinal = useCallback(
-    (next: number) => {
-      setOrdinalInternal(clampOrdinalValue(next, cardinality, defaultOrdinal));
-    },
-    [cardinality, defaultOrdinal],
-  );
-
-  const goPrev = useCallback(() => {
-    setOrdinalInternal((prev) => clampOrdinalValue(prev - 1, cardinality, defaultOrdinal));
-  }, [cardinality, defaultOrdinal]);
-
-  const goNext = useCallback(() => {
-    setOrdinalInternal((prev) => clampOrdinalValue(prev + 1, cardinality, defaultOrdinal));
-  }, [cardinality, defaultOrdinal]);
-
-  const objects = view.getObjects();
-  const currentObject = view.getObject(ordinal);
+  const currentObject = view.getObject(1) || view.getObjects()[0] || null;
   const currentUrl = currentObject?.url ?? view.getPrimaryUrl() ?? null;
-  const currentMetadata = currentObject?.metadata ?? view.getPrimaryMetadata() ?? null;
+  const currentMetadata = (currentObject?.metadata ?? view.getPrimaryMetadata()) || null;
 
-  const canGoPrev = ordinal > 1;
-  const canGoNext = cardinality ? ordinal < cardinality : true;
-
-  const ordinalsNeedingLoad = useMemo<number[]>(() => {
-    const missing: number[] = [];
-    if (!asset) {
-      return missing;
-    }
-    const safePrefetch = Math.max(1, prefetch);
-    const maxOrdinal = cardinality && cardinality > 0
-      ? Math.min(cardinality, ordinal + safePrefetch - 1)
-      : ordinal + safePrefetch - 1;
-
-    for (let ord = ordinal; ord <= maxOrdinal; ord += 1) {
-      const object = view.getObject(ord);
-      if (!object?.url) {
-        missing.push(ord);
-      }
-    }
-
-    return missing;
-  }, [asset, view, ordinal, prefetch, cardinality]);
-
-  const fetchStart = ordinalsNeedingLoad.length ? ordinalsNeedingLoad[0] : null;
-  const fetchEnd = ordinalsNeedingLoad.length
-    ? ordinalsNeedingLoad[ordinalsNeedingLoad.length - 1]
-    : null;
-  const fetchLimit = fetchStart !== null && fetchEnd !== null ? fetchEnd - fetchStart + 1 : null;
-
-  const [loading, setLoading] = useState(false);
+  const [isLoading, setIsLoading] = useState(false);
 
   useEffect(() => {
-    if (!documentId || !asset || !ensureAssetUrl) {
-      setLoading(false);
-      return;
+    if (!ensureAssetUrl || !documentId || !asset) {
+      return undefined;
     }
-    if (fetchStart === null || fetchLimit === null) {
-      setLoading(false);
-      return;
+    if (currentUrl) {
+      return undefined;
     }
-
     let cancelled = false;
-    setLoading(true);
-    ensureAssetUrl(documentId, asset, {
-      start: fetchStart,
-      limit: fetchLimit,
-    })
+    setIsLoading(true);
+    ensureAssetUrl(documentId, asset, { start: 1, limit: 1 })
       .catch(() => {})
       .finally(() => {
         if (!cancelled) {
-          setLoading(false);
+          setIsLoading(false);
         }
       });
-
     return () => {
       cancelled = true;
     };
-  }, [documentId, asset, ensureAssetUrl, fetchStart, fetchLimit]);
+  }, [asset, currentUrl, documentId, ensureAssetUrl]);
 
   return {
     document,
     documentId,
     asset,
     assetType,
-    ordinal,
-    setOrdinal,
-    goPrev,
-    goNext,
-    canGoPrev,
-    canGoNext,
-    cardinality,
-    currentObject,
     currentUrl,
     currentMetadata,
-    objects,
-    isLoading: loading,
+    isLoading,
   };
 };