feat: implement resolveGeneratedOutputPlacement function and add tests for output placement logic

operations/generation/runGenerate.ts

@@ -1,6 +1,5 @@
 import { commandIds } from "@commands/ids";
 import type { ImageDocument } from "@core/document";
-import type { Transform } from "@core/geometry";
 import type { Layer } from "@core/layer";
 import { getLayerMask } from "@core/layer-mask-utils";
 import type { AppStore } from "@editor/store";
@@ -10,6 +9,7 @@ import { buildInpaintBundle, type InpaintBundle } from "./inpaintPrep";
 import { imageSourceToDataUrl, loadImageSize } from "@platform/browser/imageRaster";
 import { requestGeneration } from "@platform/comfy/generationClient";
 import { checkGenerationPreconditions } from "./preconditions";
+import { resolveGeneratedOutputPlacement } from "./outputPlacement";
 
 export async function runGenerate(options: {
   document: ImageDocument;
@@ -41,12 +41,7 @@ export async function runGenerate(options: {
     inpaintBundle,
   });
   const intrinsicSize = await loadImageSize(generated.source);
-  const targetArtboardId = inpaintBundle?.placement.artboardId ?? artboard.id;
-  const placement = {
-    artboardId: targetArtboardId,
-    layerName: inpaintBundle?.placement.layerName ?? "Generated image",
-    transform: generatedLayerTransform(inpaintBundle, intrinsicSize),
-  };
+  const placement = resolveGeneratedOutputPlacement({ document, selection, settings, intrinsicSize, inpaintBundle });
 
   dispatch(commandIds.generationAddCandidate, {
     candidate: createGenerationCandidate({
@@ -202,18 +197,6 @@ function resolveInpaintRequest(inpaintBundle: InpaintBundle | undefined, inpaint
   return settings.inpaint;
 }
 
-function generatedLayerTransform(inpaintBundle: InpaintBundle | undefined, intrinsicSize: { w: number; h: number }): Transform {
-  if (!inpaintBundle) return { position: { x: 0, y: 0 }, scale: { x: 1, y: 1 }, rotation: 0 };
-  return {
-    position: { ...inpaintBundle.placement.transform.position },
-    scale: {
-      x: (inpaintBundle.placement.transform.scale.x * inpaintBundle.width) / Math.max(1, intrinsicSize.w),
-      y: (inpaintBundle.placement.transform.scale.y * inpaintBundle.height) / Math.max(1, intrinsicSize.h),
-    },
-    rotation: inpaintBundle.placement.transform.rotation,
-  };
-}
-
 function resolveSeed(seed: number): number {
   return seed < 0 ? Math.floor(Math.random() * 2 ** 32) : Math.round(seed);
 }