dragging

frontend/src/documents/DocumentsTable.jsx

@@ -73,6 +73,8 @@ const DocumentThumbnailImage = ({ document, ensureAssetUrl, getDocumentAsset, al
         src={url}
         alt={alt || ''}
         className="document-thumbnail"
+        draggable={false}
+        onDragStart={(event) => event.preventDefault()}
       />
     );
   }

frontend/src/index.jsx

@@ -1873,6 +1873,23 @@ const AppLayout = () => {
     [visibleDocuments],
   );
 
+  const documentLookup = useMemo(() => {
+    const map = new Map();
+    const push = (items) => {
+      (items || []).forEach((doc) => {
+        if (doc?.id) {
+          map.set(doc.id, doc);
+        }
+      });
+    };
+
+    push(documents);
+    if (Array.isArray(searchResults)) {
+      push(searchResults);
+    }
+    return map;
+  }, [documents, searchResults]);
+
   const applySelection = useCallback(
     (ids, { anchor, interactedIds = [] } = {}) => {
       const visibleSet = new Set(visibleDocumentIds);
@@ -2101,44 +2118,6 @@ const AppLayout = () => {
   }, [focusedRowKey, navigableRowKeys, focusedDocumentId]);
 
 
-  const handleDocumentDragStart = useCallback(
-    (event, documentOrId) => {
-      const documentId = typeof documentOrId === 'string' ? documentOrId : documentOrId?.id;
-      if (!documentId) {
-        return;
-      }
-
-      const isAlreadySelected = selectedDocumentIds.includes(documentId);
-      const selection = isAlreadySelected ? [...selectedDocumentIds] : [documentId];
-
-      if (!isAlreadySelected) {
-        applySelection([documentId], {
-          anchor: documentId,
-          interactedIds: [documentId],
-        });
-      }
-
-      setDraggedDocumentIds(selection);
-      event.dataTransfer.effectAllowed = 'move';
-      try {
-        event.dataTransfer.setData(
-          'application/x-papercrate-doc-list',
-          JSON.stringify(selection),
-        );
-      } catch (
-        // eslint-disable-next-line no-empty
-        error
-      ) {}
-      event.currentTarget.classList.add('dragging');
-    },
-    [selectedDocumentIds, applySelection],
-  );
-
-  const handleDocumentDragEnd = useCallback((event) => {
-    setDraggedDocumentIds([]);
-    event.currentTarget.classList.remove('dragging');
-  }, []);
-
   const ensureFolderData = useCallback(
     async (folderId, { force = false } = {}) => {
       if (!force && folderContents.has(folderId)) {
@@ -3264,6 +3243,131 @@ const AppLayout = () => {
     ],
   );
 
+  const dragPreviewRef = useRef(null);
+
+  const destroyDragPreview = useCallback(() => {
+    const node = dragPreviewRef.current;
+    if (node && node.parentNode) {
+      node.parentNode.removeChild(node);
+    }
+    dragPreviewRef.current = null;
+  }, []);
+
+  useEffect(() => destroyDragPreview, [destroyDragPreview]);
+
+  const createDragPreview = useCallback(
+    (documentsForPreview) => {
+      destroyDragPreview();
+      const docs = (documentsForPreview || []).filter(Boolean);
+      if (!docs.length) {
+        return null;
+      }
+
+      const maxVisible = 4;
+      const size = 64;
+      const canvasSize = Math.round(size * 1.6);
+      const visibleDocs = docs.slice(0, maxVisible);
+
+      const wrapper = document.createElement('div');
+      wrapper.className = 'document-drag-preview';
+      wrapper.style.setProperty('--drag-preview-size', `${canvasSize}px`);
+
+      visibleDocs.forEach((doc, index) => {
+        const layer = document.createElement('div');
+        layer.className = 'document-drag-preview__thumb';
+        const rotationMagnitude = Math.random() * 8 + 2; // 2..10 degrees
+        const rotation = (index % 2 === 0 ? 1 : -1) * rotationMagnitude;
+        layer.style.setProperty('--rotation-deg', `${rotation}deg`);
+
+        const rowEl = doc?.id ? document.getElementById(`document-row-${doc.id}`) : null;
+        const thumbnailEl = rowEl?.querySelector('.document-thumbnail');
+        const placeholderEl = rowEl?.querySelector('.thumb-placeholder');
+
+        let content = null;
+        if (thumbnailEl instanceof HTMLImageElement) {
+          content = thumbnailEl.cloneNode(true);
+          content.draggable = false;
+          content.style.pointerEvents = 'none';
+        } else if (placeholderEl instanceof HTMLElement) {
+          content = placeholderEl.cloneNode(true);
+          content.style.pointerEvents = 'none';
+        }
+
+        if (content) {
+          layer.appendChild(content);
+        } else {
+          layer.textContent = 'DOC';
+        }
+
+        wrapper.appendChild(layer);
+      });
+
+      if (docs.length > 1) {
+        const badge = document.createElement('div');
+        badge.className = 'document-drag-preview__count';
+        badge.textContent = docs.length > maxVisible ? `+${docs.length - maxVisible}` : `${docs.length}`;
+        wrapper.appendChild(badge);
+      }
+
+      document.body.appendChild(wrapper);
+      dragPreviewRef.current = wrapper;
+      return wrapper;
+    },
+    [destroyDragPreview],
+  );
+
+  const handleDocumentDragStart = useCallback(
+    (event, documentOrId) => {
+      const documentId = typeof documentOrId === 'string' ? documentOrId : documentOrId?.id;
+      if (!documentId) {
+        return;
+      }
+
+      const isAlreadySelected = selectedDocumentIds.includes(documentId);
+      const selection = isAlreadySelected ? [...selectedDocumentIds] : [documentId];
+
+      if (!isAlreadySelected) {
+        applySelection([documentId], {
+          anchor: documentId,
+          interactedIds: [documentId],
+        });
+      }
+
+      const previewDocs = selection
+        .map((id) => documentLookup.get(id) || null)
+        .filter(Boolean);
+      const previewNode = createDragPreview(previewDocs);
+
+      setDraggedDocumentIds(selection);
+      event.dataTransfer.effectAllowed = 'move';
+      try {
+        event.dataTransfer.setData(
+          'application/x-papercrate-doc-list',
+          JSON.stringify(selection),
+        );
+      } catch (
+        // eslint-disable-next-line no-empty
+        error
+      ) {}
+      if (previewNode) {
+        const width = previewNode.offsetWidth || 96;
+        const height = previewNode.offsetHeight || 96;
+        event.dataTransfer.setDragImage(previewNode, width / 2, height / 2);
+      }
+      event.currentTarget.classList.add('dragging');
+    },
+    [selectedDocumentIds, applySelection, documentLookup, createDragPreview],
+  );
+
+  const handleDocumentDragEnd = useCallback(
+    (event) => {
+      setDraggedDocumentIds([]);
+      event.currentTarget.classList.remove('dragging');
+      destroyDragPreview();
+    },
+    [destroyDragPreview],
+  );
+
   const ensurePreviewUrl = useCallback(
     async (documentId, { force = false } = {}) => {
       if (!documentId) return null;
@@ -4598,23 +4702,6 @@ const AppLayout = () => {
     return list.find((doc) => doc.id === focusedDocumentId) || null;
   }, [searchResults, documents, focusedDocumentId]);
 
-  const documentLookup = useMemo(() => {
-    const map = new Map();
-    documents.forEach((doc) => {
-      if (doc?.id) {
-        map.set(doc.id, doc);
-      }
-    });
-    if (Array.isArray(searchResults)) {
-      searchResults.forEach((doc) => {
-        if (doc?.id) {
-          map.set(doc.id, doc);
-        }
-      });
-    }
-    return map;
-  }, [documents, searchResults]);
-
   const handleDocumentDelete = useCallback(
     async (documentId) => {
       if (!documentId) return;

frontend/src/styles.css

@@ -313,6 +313,69 @@ button.icon-button.ghost:hover:not([disabled]) {
   color: var(--muted);
 }
 
+.document-drag-preview {
+  position: fixed;
+  pointer-events: none;
+  top: -9999px;
+  left: -9999px;
+  width: var(--drag-preview-size, 96px);
+  height: var(--drag-preview-size, 96px);
+  z-index: 9999;
+}
+
+.document-drag-preview__thumb {
+  position: absolute;
+  top: 50%;
+  left: 50%;
+  width: 64px;
+  height: 64px;
+  border-radius: 6px;
+  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.25);
+  overflow: hidden;
+  background-color: rgba(32, 34, 40, 0.2);
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  color: #fff;
+  font-weight: 600;
+  font-size: 0.8rem;
+  text-transform: uppercase;
+  transform: translate(-50%, -50%) rotate(var(--rotation-deg, 0deg));
+  transform-origin: center;
+}
+
+.document-drag-preview__thumb .document-thumbnail,
+.document-drag-preview__thumb img {
+  width: 100%;
+  height: 100%;
+  object-fit: cover;
+  pointer-events: none;
+}
+
+.document-drag-preview__thumb .thumb-placeholder,
+.document-drag-preview__thumb .thumb-placeholder * {
+  width: 100%;
+  height: 100%;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  pointer-events: none;
+}
+
+.document-drag-preview__count {
+  position: absolute;
+  bottom: 4px;
+  right: 4px;
+  background-color: var(--accent);
+  color: #fff;
+  border-radius: 999px;
+  padding: 0.25rem 0.5rem;
+  font-size: 0.75rem;
+  font-weight: 600;
+  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.25);
+  pointer-events: none;
+}
+
 .preview-workspace__actions {
   display: flex;
   align-items: center;