refactor

frontend/src/desktop/hooks/usePreviewMetadata.js

@@ -0,0 +1,86 @@
+import { useEffect, useState } from 'react';
+import { createAssetView } from '../../asset_manager';
+
+const usePreviewMetadata = (documents, getDocumentAsset, ensureAssetUrl) => {
+  const [metadataMap, setMetadataMap] = useState(() => new Map());
+
+  useEffect(() => {
+    let cancelled = false;
+    const docs = Array.isArray(documents) ? documents : [];
+    if (!docs.length) {
+      setMetadataMap(new Map());
+      return () => {
+        cancelled = true;
+      };
+    }
+
+    const fetchMetadataForDoc = async (doc) => {
+      if (!doc?.id) {
+        return null;
+      }
+
+      const docId = String(doc.id);
+      const resolveAsset = (type) =>
+        (typeof getDocumentAsset === 'function' ? getDocumentAsset(doc, type) : null);
+
+      let asset = resolveAsset('preview') || resolveAsset('thumbnail');
+      let view = createAssetView(asset);
+      let metadata = view.getPrimaryMetadata();
+
+      const hasDimensions = (meta) =>
+        Number.isFinite(Number(meta?.width)) &&
+        Number.isFinite(Number(meta?.height)) &&
+        Number(meta.width) > 0 &&
+        Number(meta.height) > 0;
+
+      if (!hasDimensions(metadata) && ensureAssetUrl && docId && asset?.id) {
+        try {
+          const ensured = await ensureAssetUrl(doc.id, asset, { start: 1, limit: 1 });
+          if (ensured) {
+            asset = ensured;
+            view = createAssetView(asset);
+            metadata = view.getPrimaryMetadata();
+          }
+        } catch (error) {
+          console.warn('[desk] ensureDocumentSize metadata fetch failed', error);
+        }
+      }
+
+      if (!hasDimensions(metadata)) {
+        return null;
+      }
+
+      return {
+        docId,
+        width: Number(metadata.width),
+        height: Number(metadata.height),
+      };
+    };
+
+    let mounted = true;
+    (async () => {
+      const entries = await Promise.all(docs.map(fetchMetadataForDoc));
+      if (!mounted || cancelled) {
+        return;
+      }
+      const next = new Map();
+      entries.forEach((entry) => {
+        if (entry && entry.docId) {
+          next.set(entry.docId, entry);
+        }
+      });
+      if (!cancelled) {
+        setMetadataMap(next);
+      }
+    })();
+
+    return () => {
+      cancelled = true;
+      mounted = false;
+    };
+  }, [documents, getDocumentAsset, ensureAssetUrl]);
+
+  return metadataMap;
+};
+
+export default usePreviewMetadata;