fix(layer-editor): use stable _key for drag-and-drop sorting

Add a unique `_key` to each layer config to maintain stable sortable IDs
across reorder operations. Update LayerRow to use the sortableId prop
and the `use:sortable` directive. Refactor layer-crud utilities to
generate and propagate `_key` values on creation and initialization.

content/deck-test.md

@@ -2,6 +2,8 @@
 
 :md-deck[./names.csv]{size="54x86" grid="5x8" bleed="1" padding="2" layers="name1:1,1-2,2f12 name2:4,7-5,8f12s num1:1,3-2,4f12 num2:4,5-5,6f12s"}
 
+:md-deck[./names.csv]{size="54x86" grid="5x8" layers="num1:1,1-2,2 num2:4,5-5,6f12s name1:1,1-2,2 name2:1,1-2,2 name1:1,1-2,2" }
+
 ## 使用 yaml/tag 语法创建 md-deck
 
 ```yaml/tag

src/components/md-deck/editor-panel/LayerEditorPanel.tsx

@@ -3,10 +3,10 @@ import {
   DragDropProvider,
   DragDropSensors,
   SortableProvider,
-  useDragDropContext,
   closestCenter,
 } from "@thisbeyond/solid-dnd";
 import type { DeckStore } from "../hooks/deckStore";
+import { toSortableId } from "../hooks/layer-crud";
 import { LayerRow } from "./LayerRow";
 
 export interface LayerEditorPanelProps {
@@ -26,8 +26,16 @@ function LayerEditorPanel(props: LayerEditorPanelProps) {
       ? store.state.frontLayerConfigs
       : store.state.backLayerConfigs;
 
-  // Stable IDs for SortableProvider — simply the indices
-  const ids = createMemo(() => layers().map((_, i) => i));
+  // Stable IDs from _key — don't change on reorder
+  const sortableIds = createMemo(() =>
+    layers().map((l, i) => toSortableId(l, i)),
+  );
+  // Lookup: sortable string ID → current array index
+  const idToIndex = createMemo(() => {
+    const map = new Map<string, number>();
+    layers().forEach((l, i) => map.set(toSortableId(l, i), i));
+    return map;
+  });
 
   const updater = () =>
     side() === "front"
@@ -96,23 +104,23 @@ function LayerEditorPanel(props: LayerEditorPanelProps) {
 
       <DragDropProvider
         onDragEnd={({ draggable, droppable }) => {
-          if (droppable && draggable.id !== droppable.id) {
-            store.actions.reorderLayers(
-              side(),
-              draggable.id as number,
-              droppable.id as number,
-            );
+          if (!droppable) return;
+          const from = idToIndex().get(draggable.id as string);
+          const to = idToIndex().get(droppable.id as string);
+          if (from !== undefined && to !== undefined && from !== to) {
+            store.actions.reorderLayers(side(), from, to);
           }
         }}
         collisionDetector={closestCenter}
       >
         <DragDropSensors>
-          <SortableProvider ids={ids()}>
+          <SortableProvider ids={sortableIds()}>
             <For each={layers()}>
               {(layer, index) => (
                 <LayerRow
                   store={store}
                   index={index()}
+                  sortableId={toSortableId(layer, index())}
                   layer={layer}
                   hovered={hoveredIndex() === index()}
                   onHoverChange={setHoveredIndex}

src/components/md-deck/editor-panel/LayerRow.tsx

@@ -9,6 +9,7 @@ import alignRightIcon from "./icons/align-right.png";
 export interface LayerRowProps {
   store: DeckStore;
   index: number;
+  sortableId: string;
   layer: LayerConfig;
   hovered: boolean;
   onHoverChange: (idx: number | null) => void;
@@ -64,7 +65,7 @@ function alignSrc(v: string) {
 }
 
 export function LayerRow(props: LayerRowProps) {
-  const sortable = createSortable(props.index);
+  const sortable = createSortable(props.sortableId);
   const [dndState] = useDragDropContext()!;
   const [fontOpen, setFontOpen] = createSignal(false);
   let fontRef: HTMLDivElement | undefined;
@@ -89,11 +90,12 @@ export function LayerRow(props: LayerRowProps) {
 
   return (
     <div
-      ref={sortable}
+      use:sortable={sortable}
       class={`flex items-center gap-1 py-1.5 px-1 relative group border-b border-gray-100 ${selected() ? "bg-blue-50" : ""}`}
       classList={{
         "opacity-25": sortable.isActiveDraggable,
-        "transition-transform": !!dndState.active.draggable,
+        "transition-transform":
+          !!dndState.active.draggable && !sortable.isActiveDraggable,
       }}
       onMouseEnter={() => props.onHoverChange(props.index)}
       onMouseLeave={() => props.onHoverChange(null)}

src/components/md-deck/hooks/deckStore.ts

@@ -463,8 +463,12 @@ export function createDeckStore(initialSrc: string = ""): DeckStore {
       setState({
         cards: data,
         activeTab: 0,
-        frontLayerConfigs: initLayerConfigsForSide(data, layersStr),
-        backLayerConfigs: initLayerConfigsForSide(data, backLayersStr),
+        frontLayerConfigs: layerCrud.withKeys(
+          initLayerConfigsForSide(data, layersStr),
+        ),
+        backLayerConfigs: layerCrud.withKeys(
+          initLayerConfigsForSide(data, backLayersStr),
+        ),
         isLoading: false,
       });
       updateDimensions();

src/components/md-deck/hooks/layer-crud.ts

@@ -1,8 +1,19 @@
-import type { CardSide, LayerConfig } from "../types";
+import type { LayerConfig } from "../types";
 
-/** Creates a new LayerConfig with default placement. */
+let nextKey = 1;
+
+export function resetKeyCounter(value = 1) {
+  nextKey = value;
+}
+
+/** Creates a new LayerConfig with default placement and a stable _key. */
 export function createDefaultLayer(prop: string): LayerConfig {
-  return { prop, visible: true, x1: 1, y1: 1, x2: 2, y2: 2 };
+  return { prop, visible: true, x1: 1, y1: 1, x2: 2, y2: 2, _key: nextKey++ };
+}
+
+/** Assign stable _key to layers that don't have one (e.g. parsed from string). */
+export function withKeys(layers: LayerConfig[]): LayerConfig[] {
+  return layers.map((l) => (l._key ? l : { ...l, _key: nextKey++ }));
 }
 
 /** Insert a layer and return the new array. */
@@ -11,18 +22,33 @@ export function addLayer(configs: LayerConfig[], prop: string): LayerConfig[] {
 }
 
 /** Remove a layer by index and return the new array. */
-export function removeLayer(configs: LayerConfig[], index: number): LayerConfig[] {
+export function removeLayer(
+  configs: LayerConfig[],
+  index: number,
+): LayerConfig[] {
   return configs.filter((_, i) => i !== index);
 }
 
 /** Reorder a layer within the array. Returns new array. */
-export function reorderLayers(configs: LayerConfig[], from: number, to: number): LayerConfig[] {
+export function reorderLayers(
+  configs: LayerConfig[],
+  from: number,
+  to: number,
+): LayerConfig[] {
   const next = [...configs];
   const [item] = next.splice(from, 1);
   next.splice(to, 0, item);
   return next;
 }
 
+/**
+ * Convert layer _key to flake ID (unique string) for SortableProvider.
+ * Allows multiple instances of the same field name.
+ */
+export function toSortableId(layer: LayerConfig, index: number): string {
+  return layer._key ? `layer-${layer._key}` : `layer-idx-${index}`;
+}
+
 /**
  * Recalculate selectedLayer after a structural change (add/remove/reorder).
  * Returns the new selectedLayer index, or null.
@@ -42,11 +68,12 @@ export function adjustSelectedLayer(
 
   if (action === "reorder" && to !== undefined) {
     if (currentSelected === from) return to;
-    if (from < to && currentSelected > from && currentSelected <= to) return currentSelected - 1;
-    if (from > to && currentSelected >= to && currentSelected < from) return currentSelected + 1;
+    if (from < to && currentSelected > from && currentSelected <= to)
+      return currentSelected - 1;
+    if (from > to && currentSelected >= to && currentSelected < from)
+      return currentSelected + 1;
     return currentSelected;
   }
 
-  // "add" — doesn't affect existing indices
   return currentSelected;
 }

src/components/md-deck/types.ts

@@ -2,9 +2,9 @@ export interface CardData {
   [key: string]: string;
 }
 
-export type CardSide = 'front' | 'back';
+export type CardSide = "front" | "back";
 
-export type { CardShape } from '../../plotcutter/contour';
+export type { CardShape } from "../../plotcutter/contour";
 
 export interface Layer {
   prop: string;
@@ -12,9 +12,9 @@ export interface Layer {
   y1: number;
   x2: number;
   y2: number;
-  orientation?: 'n' | 's' | 'e' | 'w';
+  orientation?: "n" | "s" | "e" | "w";
   fontSize?: number;
-  align?: 'l' | 'c' | 'r';
+  align?: "l" | "c" | "r";
 }
 
 export interface LayerConfig {
@@ -24,9 +24,10 @@ export interface LayerConfig {
   y1: number;
   x2: number;
   y2: number;
-  orientation?: 'n' | 's' | 'e' | 'w';
+  orientation?: "n" | "s" | "e" | "w";
   fontSize?: number;
-  align?: 'l' | 'c' | 'r';
+  align?: "l" | "c" | "r";
+  _key?: number;
 }
 
 export interface Dimensions {

src/solid-dnd.directives.d.ts

@@ -0,0 +1,12 @@
+import "solid-js";
+
+declare module "solid-js" {
+  namespace JSX {
+    interface Directives {
+      sortable: (
+        el: HTMLElement,
+        accessor: () => boolean | { skipTransform?: boolean } | undefined,
+      ) => void;
+    }
+  }
+}