From b1006e2bfd0a8452ab47977c56e0a9ecc920b00c Mon Sep 17 00:00:00 2001
From: Mark Tolmacs <mark@lazycat.hu>
Date: Sun, 14 Sep 2025 14:05:55 +0200
Subject: [PATCH] fix: Locked elbow arrow creation

---
 packages/element/src/linearElementEditor.ts | 30 ++++++++++++---------
 1 file changed, 17 insertions(+), 13 deletions(-)

diff --git a/packages/element/src/linearElementEditor.ts b/packages/element/src/linearElementEditor.ts
index 4a89f21ca..6905497a0 100644
--- a/packages/element/src/linearElementEditor.ts
+++ b/packages/element/src/linearElementEditor.ts
@@ -397,9 +397,11 @@ export class LinearElementEditor {
   ): Pick<AppState, "suggestedBinding" | "selectedLinearElement"> | null {
     const elementsMap = app.scene.getNonDeletedElementsMap();
     const elements = app.scene.getNonDeletedElements();
-    const { elbowed, elementId, initialState, selectedPointsIndices } =
-      linearElementEditor;
-    const { lastClickedPoint } = initialState;
+    const { elbowed, elementId, initialState } = linearElementEditor;
+    const selectedPointsIndices = Array.from(
+      linearElementEditor.selectedPointsIndices ?? [],
+    );
+    let { lastClickedPoint } = initialState;
     const element = LinearElementEditor.getElement(elementId, elementsMap);
 
     invariant(element, "Element being dragged must exist in the scene");
@@ -411,6 +413,18 @@ export class LinearElementEditor {
       "There must be selected points in order to drag them",
     );
 
+    if (elbowed) {
+      selectedPointsIndices.some((pointIdx, idx) => {
+        if (pointIdx > 0 && pointIdx !== element.points.length - 1) {
+          selectedPointsIndices[idx] = element.points.length - 1;
+          lastClickedPoint = element.points.length - 1;
+          return true;
+        }
+
+        return false;
+      });
+    }
+
     invariant(
       lastClickedPoint > -1 &&
         selectedPointsIndices.includes(lastClickedPoint) &&
@@ -422,16 +436,6 @@ export class LinearElementEditor {
       }) lastClickedPoint(${lastClickedPoint})`,
     );
 
-    invariant(
-      !elbowed ||
-        selectedPointsIndices?.filter(
-          (idx) => idx !== 0 && idx !== element.points.length - 1,
-        ).length === 0,
-      `Only start and end points can be selected for elbow arrows: ${JSON.stringify(
-        selectedPointsIndices,
-      )} end point ${element.points.length - 1}`,
-    );
-
     // point that's being dragged (out of all selected points)
     const draggingPoint = element.points[lastClickedPoint];
     // The adjacent point to the one dragged point