refactor: add some part management utilities

src/samples/boop/index.ts

@@ -1,4 +1,4 @@
-import {createGameCommandRegistry, Part, MutableSignal, createRegion} from '@/index';
+import {createGameCommandRegistry, Part, MutableSignal, createRegion, createPart, isCellOccupied as isCellOccupiedUtil, getPartAtPosition} from '@/index';
 
 const BOARD_SIZE = 6;
 const MAX_PIECES_PER_PLAYER = 8;
@@ -8,7 +8,7 @@ export type PlayerType = 'white' | 'black';
 export type PieceType = 'kitten' | 'cat';
 export type WinnerType = PlayerType | 'draw' | null;
 
-type BoopPart = Part & { player: PlayerType; pieceType: PieceType };
+type BoopPart = Part<{ player: PlayerType; pieceType: PieceType }>;
 
 type PieceSupply = { supply: number; placed: number };
 
@@ -157,15 +157,11 @@ export function getBoardRegion(host: MutableSignal<BoopState>) {
 }
 
 export function isCellOccupied(host: MutableSignal<BoopState>, row: number, col: number): boolean {
-    const board = getBoardRegion(host);
-    return board.partMap[`${row},${col}`] !== undefined;
+    return isCellOccupiedUtil(host.value.pieces, 'board', [row, col]);
 }
 
 export function getPartAt(host: MutableSignal<BoopState>, row: number, col: number): BoopPart | null {
-    const board = getBoardRegion(host);
-    const partId = board.partMap[`${row},${col}`];
-    if (!partId) return null;
-    return host.value.pieces.find(p => p.id === partId) || null;
+    return getPartAtPosition(host.value.pieces, 'board', [row, col]) || null;
 }
 
 export function placePiece(host: MutableSignal<BoopState>, row: number, col: number, player: PlayerType, pieceType: PieceType) {
@@ -173,13 +169,10 @@ export function placePiece(host: MutableSignal<BoopState>, row: number, col: num
     const playerData = getPlayer(host, player);
     const count = playerData[pieceType].placed + 1;
 
-    const piece: BoopPart = {
-        id: `${player}-${pieceType}-${count}`,
-        regionId: 'board',
-        position: [row, col],
-        player,
-        pieceType,
-    };
+    const piece = createPart<{ player: PlayerType; pieceType: PieceType }>(
+        { regionId: 'board', position: [row, col], player, pieceType },
+        `${player}-${pieceType}-${count}`
+    );
     host.produce(s => {
         s.pieces.push(piece);
         board.childIds.push(piece.id);