refactor(transform): resolve target bounds

editor/transform-targets.test.ts

@@ -0,0 +1,34 @@
+import { describe, expect, test } from "bun:test";
+import type { ImageDocument } from "@core/document";
+import { applyTransformTargetBounds, resolveTransformTargetBounds, selectedTransformTarget } from "./transform-targets";
+
+const document: ImageDocument = {
+  id: "d1",
+  name: "Test",
+  version: 1,
+  assets: [],
+  artboards: [
+    {
+      id: "a1",
+      name: "Artboard",
+      bounds: { x: 0, y: 0, w: 100, h: 80 },
+      backgroundColor: "transparent",
+      layers: [],
+    },
+  ],
+};
+
+describe("transform targets", () => {
+  test("selects layer target before artboard target", () => {
+    expect(selectedTransformTarget(document, { artboardId: "a1", layerIds: ["l1"] })).toEqual({ type: "layer", id: "l1" });
+  });
+
+  test("resolves artboard bounds", () => {
+    expect(resolveTransformTargetBounds(document, { type: "artboard", id: "a1" })).toEqual({ x: 0, y: 0, w: 100, h: 80 });
+  });
+
+  test("applies artboard bounds", () => {
+    const next = applyTransformTargetBounds(document, { type: "artboard", id: "a1" }, { x: 10, y: 20, w: 200, h: 160 });
+    expect(next.artboards[0]?.bounds).toEqual({ x: 10, y: 20, w: 200, h: 160 });
+  });
+});