feat(ui): drag-and-drop reordering for reference images

invokeai/frontend/web/src/features/controlLayers/components/RefImage/RefImageList.helpers.test.ts

@@ -0,0 +1,192 @@
+import { describe, expect, it } from 'vitest';
+
+import { getReorderedRefImageIds } from './RefImageList.helpers';
+
+const IDS = ['a', 'b', 'c', 'd'];
+
+describe('getReorderedRefImageIds', () => {
+  describe('no-op cases', () => {
+    it('returns null when sourceId is not in the list', () => {
+      const result = getReorderedRefImageIds({
+        ids: IDS,
+        sourceId: 'missing',
+        targetId: 'b',
+        closestEdgeOfTarget: 'left',
+      });
+      expect(result).toBeNull();
+    });
+
+    it('returns null when targetId is not in the list', () => {
+      const result = getReorderedRefImageIds({
+        ids: IDS,
+        sourceId: 'a',
+        targetId: 'missing',
+        closestEdgeOfTarget: 'left',
+      });
+      expect(result).toBeNull();
+    });
+
+    it('returns null when sourceId and targetId are the same', () => {
+      const result = getReorderedRefImageIds({
+        ids: IDS,
+        sourceId: 'b',
+        targetId: 'b',
+        closestEdgeOfTarget: 'left',
+      });
+      expect(result).toBeNull();
+    });
+
+    it('returns null when source is already immediately to the left of target with edge=left', () => {
+      // 'a' is at index 0, 'b' is at index 1. Dropping 'a' on the left edge of 'b' is a no-op.
+      const result = getReorderedRefImageIds({
+        ids: IDS,
+        sourceId: 'a',
+        targetId: 'b',
+        closestEdgeOfTarget: 'left',
+      });
+      expect(result).toBeNull();
+    });
+
+    it('returns null when source is already immediately to the right of target with edge=right', () => {
+      // 'b' is at index 1, 'a' is at index 0. Dropping 'b' on the right edge of 'a' is a no-op.
+      const result = getReorderedRefImageIds({
+        ids: IDS,
+        sourceId: 'b',
+        targetId: 'a',
+        closestEdgeOfTarget: 'right',
+      });
+      expect(result).toBeNull();
+    });
+  });
+
+  describe('forward moves (sourceIndex < targetIndex)', () => {
+    it('moves source after target when edge=right', () => {
+      // Move 'a' (0) to the right of 'c' (2) → ['b','c','a','d']
+      const result = getReorderedRefImageIds({
+        ids: IDS,
+        sourceId: 'a',
+        targetId: 'c',
+        closestEdgeOfTarget: 'right',
+      });
+      expect(result).toEqual(['b', 'c', 'a', 'd']);
+    });
+
+    it('moves source before target when edge=left', () => {
+      // Move 'a' (0) to the left of 'c' (2) → ['b','a','c','d']
+      const result = getReorderedRefImageIds({
+        ids: IDS,
+        sourceId: 'a',
+        targetId: 'c',
+        closestEdgeOfTarget: 'left',
+      });
+      expect(result).toEqual(['b', 'a', 'c', 'd']);
+    });
+  });
+
+  describe('backward moves (sourceIndex > targetIndex)', () => {
+    it('moves source after target when edge=right', () => {
+      // Move 'd' (3) to the right of 'a' (0) → ['a','d','b','c']
+      const result = getReorderedRefImageIds({
+        ids: IDS,
+        sourceId: 'd',
+        targetId: 'a',
+        closestEdgeOfTarget: 'right',
+      });
+      expect(result).toEqual(['a', 'd', 'b', 'c']);
+    });
+
+    it('moves source before target when edge=left', () => {
+      // Move 'd' (3) to the left of 'b' (1) → ['a','d','b','c']
+      const result = getReorderedRefImageIds({
+        ids: IDS,
+        sourceId: 'd',
+        targetId: 'b',
+        closestEdgeOfTarget: 'left',
+      });
+      expect(result).toEqual(['a', 'd', 'b', 'c']);
+    });
+  });
+
+  describe('null edge', () => {
+    it('moves source to the target index when closestEdgeOfTarget is null (forward)', () => {
+      // pragmatic-dnd's reorderWithEdge collapses null edge to indexOfTarget destination.
+      // Move 'a' (0) onto 'c' (2) with no edge → ['b','c','a','d']
+      const result = getReorderedRefImageIds({
+        ids: IDS,
+        sourceId: 'a',
+        targetId: 'c',
+        closestEdgeOfTarget: null,
+      });
+      expect(result).toEqual(['b', 'c', 'a', 'd']);
+    });
+
+    it('moves source to the target index when closestEdgeOfTarget is null (backward)', () => {
+      // Move 'd' (3) onto 'b' (1) with no edge → ['a','d','b','c']
+      const result = getReorderedRefImageIds({
+        ids: IDS,
+        sourceId: 'd',
+        targetId: 'b',
+        closestEdgeOfTarget: null,
+      });
+      expect(result).toEqual(['a', 'd', 'b', 'c']);
+    });
+  });
+
+  describe('exhaustive (sourceIndex, targetIndex, edge) matrix', () => {
+    // For each ordered (source, target) pair where source !== target, verify the result for
+    // each possible edge. This catches any swap of 'left'/'right' or wrong axis handling.
+    type Edge = 'left' | 'right' | null;
+    const edges: Edge[] = ['left', 'right', null];
+
+    const expectedFor = (sourceIdx: number, targetIdx: number, edge: Edge): string[] | null => {
+      // Hand-rolled reference implementation — independent of the helper under test.
+      // Returns null for no-ops that mirror the helper's short-circuits.
+      if (sourceIdx === targetIdx) {
+        return null;
+      }
+      let edgeIndexDelta = 0;
+      if (edge === 'right') {
+        edgeIndexDelta = 1;
+      } else if (edge === 'left') {
+        edgeIndexDelta = -1;
+      }
+      if (sourceIdx === targetIdx + edgeIndexDelta) {
+        return null;
+      }
+      // Compute destination per pragmatic-dnd's `getReorderDestinationIndex` for axis='horizontal'.
+      let destination: number;
+      if (edge === null) {
+        destination = targetIdx;
+      } else {
+        const isGoingAfter = edge === 'right';
+        const isMovingForward = sourceIdx < targetIdx;
+        if (isMovingForward) {
+          destination = isGoingAfter ? targetIdx : targetIdx - 1;
+        } else {
+          destination = isGoingAfter ? targetIdx + 1 : targetIdx;
+        }
+      }
+      const next = IDS.slice();
+      const [moved] = next.splice(sourceIdx, 1);
+      next.splice(destination, 0, moved!);
+      return next;
+    };
+
+    for (let s = 0; s < IDS.length; s++) {
+      for (let t = 0; t < IDS.length; t++) {
+        for (const edge of edges) {
+          const label = `source=${s} target=${t} edge=${edge ?? 'null'}`;
+          it(label, () => {
+            const result = getReorderedRefImageIds({
+              ids: IDS,
+              sourceId: IDS[s]!,
+              targetId: IDS[t]!,
+              closestEdgeOfTarget: edge,
+            });
+            expect(result).toEqual(expectedFor(s, t, edge));
+          });
+        }
+      }
+    }
+  });
+});

invokeai/frontend/web/src/features/controlLayers/components/RefImage/RefImageList.helpers.ts

@@ -0,0 +1,60 @@
+import type { Edge } from '@atlaskit/pragmatic-drag-and-drop-hitbox/closest-edge';
+import { reorderWithEdge } from '@atlaskit/pragmatic-drag-and-drop-hitbox/util/reorder-with-edge';
+
+type GetReorderedRefImageIdsParams = {
+  ids: string[];
+  sourceId: string;
+  targetId: string;
+  closestEdgeOfTarget: Edge | null;
+};
+
+/**
+ * Computes the reordered id list for a horizontal ref-image drag-and-drop.
+ *
+ * Returns `null` for any drop that should be a no-op:
+ * - Source or target id not present in `ids`.
+ * - Source and target are the same item.
+ * - The item is already on the side of the target indicated by `closestEdgeOfTarget`.
+ *
+ * Notes on `closestEdgeOfTarget = null`: pragmatic-dnd's `extractClosestEdge` may return `null`
+ * when the hitbox util cannot determine a side. `reorderWithEdge` then treats the destination
+ * as `indexOfTarget` (i.e. moves the source onto the target's slot). The no-op short-circuit
+ * cannot fire in this case (`edgeIndexDelta` is 0, but `indexOfSource === indexOfTarget` was
+ * already rejected), so the move is forwarded to the util.
+ */
+export const getReorderedRefImageIds = ({
+  ids,
+  sourceId,
+  targetId,
+  closestEdgeOfTarget,
+}: GetReorderedRefImageIdsParams): string[] | null => {
+  const indexOfSource = ids.indexOf(sourceId);
+  const indexOfTarget = ids.indexOf(targetId);
+
+  if (indexOfTarget < 0 || indexOfSource < 0) {
+    return null;
+  }
+
+  if (indexOfSource === indexOfTarget) {
+    return null;
+  }
+
+  let edgeIndexDelta = 0;
+  if (closestEdgeOfTarget === 'right') {
+    edgeIndexDelta = 1;
+  } else if (closestEdgeOfTarget === 'left') {
+    edgeIndexDelta = -1;
+  }
+
+  if (indexOfSource === indexOfTarget + edgeIndexDelta) {
+    return null;
+  }
+
+  return reorderWithEdge({
+    list: ids,
+    startIndex: indexOfSource,
+    indexOfTarget,
+    closestEdgeOfTarget,
+    axis: 'horizontal',
+  });
+};

invokeai/frontend/web/src/features/controlLayers/components/RefImage/RefImageList.tsx

@@ -1,6 +1,9 @@
+import { monitorForElements } from '@atlaskit/pragmatic-drag-and-drop/element/adapter';
+import { extractClosestEdge } from '@atlaskit/pragmatic-drag-and-drop-hitbox/closest-edge';
 import { Button, Collapse, Divider, Flex, IconButton } from '@invoke-ai/ui-library';
-import { useAppSelector, useAppStore } from 'app/store/storeHooks';
+import { useAppDispatch, useAppSelector, useAppStore } from 'app/store/storeHooks';
 import { useImageUploadButton } from 'common/hooks/useImageUploadButton';
+import { colorTokenToCssVar } from 'common/util/colorTokenToCssVar';
 import { RefImagePreview } from 'features/controlLayers/components/RefImage/RefImagePreview';
 import { CanvasManagerProviderGate } from 'features/controlLayers/contexts/CanvasManagerProviderGate';
 import { RefImageIdContext } from 'features/controlLayers/contexts/RefImageIdContext';
@@ -9,26 +12,72 @@ import { useNewGlobalReferenceImageFromBbox } from 'features/controlLayers/hooks
 import { useCanvasIsBusySafe } from 'features/controlLayers/hooks/useCanvasIsBusy';
 import {
   refImageAdded,
+  refImagesReordered,
   selectIsRefImagePanelOpen,
   selectRefImageEntityIds,
   selectSelectedRefEntityId,
 } from 'features/controlLayers/store/refImagesSlice';
 import { imageDTOToCroppableImage } from 'features/controlLayers/store/util';
-import { addGlobalReferenceImageDndTarget } from 'features/dnd/dnd';
+import { addGlobalReferenceImageDndTarget, singleRefImageDndSource } from 'features/dnd/dnd';
 import { DndDropTarget } from 'features/dnd/DndDropTarget';
+import { triggerPostMoveFlash } from 'features/dnd/util';
 import { selectActiveTab } from 'features/ui/store/uiSelectors';
-import { memo, useMemo } from 'react';
+import { memo, useEffect, useMemo } from 'react';
+import { flushSync } from 'react-dom';
 import { useTranslation } from 'react-i18next';
 import { PiBoundingBoxBold, PiUploadBold } from 'react-icons/pi';
 import type { ImageDTO } from 'services/api/types';
 
 import { RefImageHeader } from './RefImageHeader';
+import { getReorderedRefImageIds } from './RefImageList.helpers';
 import { RefImageSettings } from './RefImageSettings';
 
 export const RefImageList = memo(() => {
   const ids = useAppSelector(selectRefImageEntityIds);
   const isPanelOpen = useAppSelector(selectIsRefImagePanelOpen);
   const selectedEntityId = useAppSelector(selectSelectedRefEntityId);
+  const dispatch = useAppDispatch();
+
+  useEffect(() => {
+    return monitorForElements({
+      canMonitor({ source }) {
+        return singleRefImageDndSource.typeGuard(source.data);
+      },
+      onDrop({ location, source }) {
+        const target = location.current.dropTargets[0];
+        if (!target) {
+          return;
+        }
+
+        const sourceData = source.data;
+        const targetData = target.data;
+
+        if (!singleRefImageDndSource.typeGuard(sourceData) || !singleRefImageDndSource.typeGuard(targetData)) {
+          return;
+        }
+
+        const nextIds = getReorderedRefImageIds({
+          ids,
+          sourceId: sourceData.payload.id,
+          targetId: targetData.payload.id,
+          closestEdgeOfTarget: extractClosestEdge(targetData),
+        });
+
+        if (nextIds === null) {
+          return;
+        }
+
+        flushSync(() => {
+          dispatch(refImagesReordered({ ids: nextIds }));
+        });
+
+        const element = document.querySelector(`[data-ref-image-id="${sourceData.payload.id}"]`);
+        if (element instanceof HTMLElement) {
+          triggerPostMoveFlash(element, colorTokenToCssVar('base.700'));
+        }
+      },
+    });
+  }, [dispatch, ids]);
 
   return (
     <Flex flexDir="column">