Merge fix/pet-stays-on-external-display: keep pet on its current display

Author: alvinunreal

apps/desktop/src/display.ts

@@ -26,8 +26,12 @@ export function getDefaultPetInitialPosition(size: WindowSize = defaultPetWindow
   };
 }
 
-export function clampToPrimaryWorkArea(position: Point, size: WindowSize = defaultPetWindowSize): Point {
-  const { workArea } = screen.getPrimaryDisplay();
+export function clampToVisibleWorkArea(position: Point, size: WindowSize = defaultPetWindowSize): Point {
+  // Clamp to the display the pet currently lives on (the one nearest its centre),
+  // not the primary display — otherwise a pet on an external monitor gets yanked
+  // back to the built-in screen whenever its position is read, saved, or restored.
+  const centre = { x: position.x + size.width / 2, y: position.y + size.height / 2 };
+  const { workArea } = screen.getDisplayNearestPoint(centre);
   const minX = workArea.x;
   const minY = workArea.y;
   const maxX = workArea.x + Math.max(0, workArea.width - size.width);

apps/desktop/src/pet-window.ts

@@ -4,7 +4,7 @@ import { join } from "node:path";
 import { pathToFileURL } from "node:url";
 
 import { getAppStateSnapshot, markPetBroken, type PetScaleValue } from "./app-state.js";
-import { clampToPrimaryWorkArea, defaultPetWindowSize, getDefaultPetInitialPosition, type Point } from "./display.js";
+import { clampToVisibleWorkArea, defaultPetWindowSize, getDefaultPetInitialPosition, type Point } from "./display.js";
 import { builtInPet } from "./built-in-pet.js";
 import { getInstalledPetDir } from "./pet-paths.js";
 import type { OpenPetsReaction } from "./local-ipc-protocol.js";
@@ -582,12 +582,12 @@ function tryUpdateLoadedPetContent(window: BrowserWindow, render: PetContentRend
 }
 
 export function getSafeDefaultPetPosition(position: Point | undefined): Point {
-  return clampToPrimaryWorkArea(position ?? getDefaultPetInitialPosition(), defaultPetWindowSize);
+  return clampToVisibleWorkArea(position ?? getDefaultPetInitialPosition(), defaultPetWindowSize);
 }
 
 export function readWindowPosition(window: BrowserWindow): Point {
   const [x, y] = window.getPosition();
-  return clampToPrimaryWorkArea({ x, y }, defaultPetWindowSize);
+  return clampToVisibleWorkArea({ x, y }, defaultPetWindowSize);
 }
 
 function applyLinuxPetWindowShape(window: BrowserWindow, scale: PetScaleValue, hasBubble: boolean): void {