/**
 * Tileset 处理器（存根）
 *
 * 后续接入 Tileset 自动扩展和拼接逻辑后替换。
 */

const STUB_DELAY_MS = 100;

export interface TilesetProcessParams {
  imageUrl: string;
  tileSize: number;
  gridSize: number;
}

export interface TilesetResult {
  buffer: Buffer;
  tileSize: number;
  gridSize: number;
  tileCount: number;
}

export class TilesetProcessor {
  /**
   * 处理 Tileset：将单张图像扩展为网格 Tileset
   * 存根实现：返回 mock 结果
   */
  async processTileset(params: TilesetProcessParams): Promise<TilesetResult> {
    await new Promise(resolve => setTimeout(resolve, STUB_DELAY_MS));

    const tileCount = params.gridSize * params.gridSize;
    // 返回 mock 1x1 PNG buffer
    const buffer = Buffer.from(
      'iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mP8/5+hHgAHggJ/PchI7wAAAABJRU5ErkJggg==',
      'base64',
    );

    return {
      buffer,
      tileSize: params.tileSize,
      gridSize: params.gridSize,
      tileCount,
    };
  }
}