/** WoW's twelve row-major 256px tiles are cropped to the client map's 1002x668 rectangle. */
export function stitchMap(tiles) {
  if (tiles.length !== 12) throw new Error("A map requires all twelve tiles");
  const width = 1002, height = 668, pixels = Buffer.alloc(width * height * 4);
  tiles.forEach((tile, index) => {
    if (tile.width !== 256 || tile.height !== 256) throw new Error("Unexpected map tile dimensions");
    const x = (index % 4) * 256, y = Math.floor(index / 4) * 256;
    const copyWidth = Math.min(256, width - x), copyHeight = Math.min(256, height - y);
    for (let row = 0; row < copyHeight; row += 1) tile.pixels.copy(pixels, ((y + row) * width + x) * 4, row * 256 * 4, (row * 256 + copyWidth) * 4);
  });
  return { width, height, pixels };
}