1 files changed, 12 insertions, 9 deletions
diff --git a/src/client/views/collections/CollectionSubView.tsx b/src/client/views/collections/CollectionSubView.tsx
index 59a695a3d..32198e3a2 100644
--- a/src/client/views/collections/CollectionSubView.tsx
+++ b/src/client/views/collections/CollectionSubView.tsx
@@ -4,7 +4,7 @@ import * as rp from 'request-promise';
 import { Utils, returnFalse } from '../../../Utils';
 import CursorField from '../../../fields/CursorField';
 import { Doc, DocListCast, Field, Opt, StrListCast } from '../../../fields/Doc';
-import { AclPrivate } from '../../../fields/DocSymbols';
+import { AclPrivate, DocData } from '../../../fields/DocSymbols';
 import { Id } from '../../../fields/FieldSymbols';
 import { List } from '../../../fields/List';
 import { listSpec } from '../../../fields/Schema';
@@ -15,13 +15,13 @@ import { GestureUtils } from '../../../pen-gestures/GestureUtils';
 import { DocServer } from '../../DocServer';
 import { Networking } from '../../Network';
 import { CollectionViewType, DocumentType } from '../../documents/DocumentTypes';
+import { ViewBoxBaseComponent } from '../DocComponent';
 import { DocUtils, Docs, DocumentOptions } from '../../documents/Documents';
 import { DragManager, dropActionType } from '../../util/DragManager';
 import { ImageUtils } from '../../util/Import & Export/ImageUtils';
 import { SelectionManager } from '../../util/SelectionManager';
 import { SnappingManager } from '../../util/SnappingManager';
 import { UndoManager, undoBatch } from '../../util/UndoManager';
-import { ViewBoxBaseComponent } from '../DocComponent';
 import { LoadingBox } from '../nodes/LoadingBox';
 import { FormattedTextBox } from '../nodes/formattedText/FormattedTextBox';
 import { CollectionView, CollectionViewProps } from './CollectionView';
@@ -196,13 +196,16 @@ export function CollectionSubView<X>(moreProps?: X) {
         @undoBatch
         protected onGesture(e: Event, ge: GestureUtils.GestureEvent) {}
 
-        protected onInternalPreDrop(e: Event, de: DragManager.DropEvent, dropAction: dropActionType) {
-            if (de.complete.docDragData) {
-                // if the dropEvent's dragAction is, say 'embed', but we're just dragging within a collection, we may not actually want to make an embedding.
-                // so we check if our collection has a dropAction set on it and if so, we use that instead.
-                if (dropAction && !de.complete.docDragData.draggedDocuments.some(d => d.embedContainer === this.Document && this.childDocs.includes(d))) {
-                    de.complete.docDragData.dropAction = dropAction;
-                }
+        protected onInternalPreDrop(e: Event, de: DragManager.DropEvent, targetDropAction: dropActionType) {
+            const dragData = de.complete.docDragData;
+            if (dragData) {
+                const sourceDragAction = dragData.dropAction;
+                const sameCollection = !dragData.draggedDocuments.some(d => d.embedContainer !== this._props.Document);
+                dragData.dropAction = !sameCollection // if doc from another tree
+                    ? sourceDragAction || targetDropAction // then use the source's dragAction otherwise the target's
+                    : sourceDragAction === dropActionType.inPlace // if source drag is inPlace
+                      ? sourceDragAction // keep the doc in place
+                      : dropActionType.same; // otherwise use same tree semantics to move within tree
                 e.stopPropagation();
             }
         }