refactor: improve inventory item interaction and state

- Decouple hit area calculation from the rendering effect in
  `InventoryItemContainer`.
- Implement a dedicated `hitArea` property to track cell rectangles.
- Update `setupInteractive` to use the container itself as the hit area
  with a custom callback.
- Move drag-and-drop logic into a dedicated `setupDnDEffect` method.
- Add `addPreviewRotation` to `InventoryItemState` for cleaner rotation
  updates.
- Normalize `previewRotation` to stay within 0-360 degrees.

packages/sts-like-viewer/src/gameobjects/InventoryItemContainer.ts

@@ -2,15 +2,14 @@ import Phaser from "phaser";
 import { dragDropEventEffect, DragDropEventType } from "boardgame-phaser";
 import { GRID_CONFIG } from "@/config";
 import {
-  IDENTITY_TRANSFORM,
   ParsedShape,
+  Point2D,
   Transform2D,
   transformShape,
   type GameItem,
 } from "boardgame-core/samples/slay-the-spire-like";
 import { DisposableBag } from "../../../framework/dist";
 import { InventoryItemState } from "@/state/InventoryItemState";
-import { effect } from "@preact/signals-core";
 
 export interface InventoryItemContainerCallbacks {
   onMoveItem: (
@@ -23,6 +22,7 @@ export interface InventoryItemContainerCallbacks {
 
 export class InventoryItemContainer extends Phaser.GameObjects.Container {
   private itemState: InventoryItemState;
+  private hitArea: Point2D[] = [];
 
   constructor(
     scene: Phaser.Scene,
@@ -41,6 +41,7 @@ export class InventoryItemContainer extends Phaser.GameObjects.Container {
       GRID_CONFIG.ITEM_NAME_STYLE,
     );
     this.add([graphics, label]);
+    this.setupInteractive();
 
     this.itemState = new InventoryItemState();
 
@@ -50,20 +51,18 @@ export class InventoryItemContainer extends Phaser.GameObjects.Container {
       label.setText(this.itemState.name.value);
     });
 
-    disposables.add(
-      effect(() => {
-        graphics.clear();
-        if (!this.itemState.shape.value) return;
-        const cellRects = this.renderGraphics(
-          graphics,
-          this.itemState.shape.value,
-          this.itemState.color.value,
-          this.itemState.previewRotation.value,
-        );
+    disposables.add(this.setupDnDEffect());
 
-        return this.setupInteractive(cellRects);
-      }),
-    );
+    disposables.addEffect(() => {
+      graphics.clear();
+      if (!this.itemState.shape.value) return;
+      this.hitArea = this.renderGraphics(
+        graphics,
+        this.itemState.shape.value,
+        this.itemState.color.value,
+        this.itemState.previewRotation.value,
+      );
+    });
 
     disposables.addEffect(() => {
       if (!this.itemState.transform.value) return;
@@ -81,7 +80,7 @@ export class InventoryItemContainer extends Phaser.GameObjects.Container {
     shape: ParsedShape,
     itemColor: number,
     rotation: number,
-  ): { x: number; y: number }[] {
+  ) {
     const transform: Transform2D = {
       offset: { x: 0, y: 0 },
       rotation,
@@ -109,17 +108,17 @@ export class InventoryItemContainer extends Phaser.GameObjects.Container {
     return cellRects;
   }
 
-  private setupInteractive(cellRects: { x: number; y: number }[]) {
+  private setupInteractive() {
     this.setScrollFactor(0);
     const cellSize = GRID_CONFIG.VIEWER_CELL_SIZE;
     this.setInteractive({
-      hitArea: cellRects,
+      hitArea: this,
       hitAreaCallback: (
-        hitArea: { x: number; y: number }[],
+        hitArea: InventoryItemContainer,
         x: number,
         y: number,
       ) =>
-        hitArea.some(
+        hitArea.hitArea.some(
           (cell) =>
             x >= cell.x &&
             x < cell.x + cellSize &&
@@ -128,11 +127,12 @@ export class InventoryItemContainer extends Phaser.GameObjects.Container {
         ),
       useHandCursor: true,
     } as Phaser.Types.Input.InputConfiguration);
+  }
 
+  private setupDnDEffect() {
     let startX = 0;
     let startY = 0;
     return dragDropEventEffect(this, (event) => {
-      console.log(event.type);
       if (event.type === DragDropEventType.DOWN) {
         startX = this.x;
         startY = this.y;
@@ -141,8 +141,7 @@ export class InventoryItemContainer extends Phaser.GameObjects.Container {
         this.x = startX + event.deltaX;
         this.y = startY + event.deltaY;
       } else if (event.type === DragDropEventType.ALTBUTTON) {
-        const current = this.itemState.previewRotation.peek();
-        this.itemState.setPreviewRotation(current + 90);
+        this.itemState.addPreviewRotation(90);
       } else if (event.type === DragDropEventType.UP) {
         this.setAlpha(1);
         const finalRotation = this.itemState.previewRotation.peek();

packages/sts-like-viewer/src/state/InventoryItemState.ts

@@ -33,7 +33,7 @@ export class InventoryItemState {
 
     this.previewRotation = computed(() => {
       const base = this._item.value?.transform?.rotation ?? 0;
-      return base + this._previewRotation.value;
+      return (base + this._previewRotation.value) % 360;
     });
   }
 
@@ -50,6 +50,10 @@ export class InventoryItemState {
     this._previewRotation.value = rotation;
   }
 
+  addPreviewRotation(rotation: number): void {
+    this._previewRotation.value += rotation;
+  }
+
   private computeColor(itemId: string): number {
     const hash = itemId.split("").reduce((acc, c) => acc + c.charCodeAt(0), 0);
     return ITEM_COLORS[hash % ITEM_COLORS.length];