fix: editor layout and SceneGraph refinements

editor/composables/useLayout.ts

@@ -12,12 +12,39 @@ interface EdgeInfo {
 
 const NODE_W = 180
 const NODE_H = 60
+const POSITIONS_KEY = 'editor_positions'
+
+export function loadSavedPositions(): Record<string, { x: number; y: number }> {
+  try {
+    return JSON.parse(localStorage.getItem(POSITIONS_KEY) || '{}')
+  } catch { return {} }
+}
+
+export function savePosition(nodeId: string, x: number, y: number) {
+  const saved = loadSavedPositions()
+  saved[nodeId] = { x, y }
+  localStorage.setItem(POSITIONS_KEY, JSON.stringify(saved))
+}
 
 export function computePositions(
   nodes: NodeInfo[],
   edges: EdgeInfo[],
   _startScene: string,
 ): Map<string, { x: number; y: number }> {
+  const saved = loadSavedPositions()
+  const result = new Map<string, { x: number; y: number }>()
+
+  const unsaved: NodeInfo[] = []
+  for (const n of nodes) {
+    if (saved[n.id]) {
+      result.set(n.id, saved[n.id])
+    } else {
+      unsaved.push(n)
+    }
+  }
+
+  if (unsaved.length === 0) return result
+
   const g = new dagre.graphlib.Graph()
   g.setGraph({
     rankdir: 'LR',
@@ -28,11 +55,11 @@ export function computePositions(
   })
   g.setDefaultEdgeLabel(() => ({}))
 
-  for (const n of nodes) {
+  for (const n of unsaved) {
     g.setNode(n.id, { width: NODE_W, height: NODE_H })
   }
 
-  const nodeIds = new Set(nodes.map((n) => n.id))
+  const nodeIds = new Set(unsaved.map((n) => n.id))
   for (const e of edges) {
     if (nodeIds.has(e.source) && nodeIds.has(e.target)) {
       g.setEdge(e.source, e.target)
@@ -41,13 +68,12 @@ export function computePositions(
 
   dagre.layout(g)
 
-  const positions = new Map<string, { x: number; y: number }>()
-  for (const n of nodes) {
+  for (const n of unsaved) {
     const node = g.node(n.id)
     if (node) {
-      positions.set(n.id, { x: node.x - NODE_W / 2, y: node.y - NODE_H / 2 })
+      result.set(n.id, { x: node.x - NODE_W / 2, y: node.y - NODE_H / 2 })
     }
   }
 
-  return positions
+  return result
 }