import Taro from '@tarojs/taro';

const MAX_BYTES = 10 * 1024 * 1024;

/** 小程序临时文件超过 10MB 时用 compressImage 压缩后再上传 */
export async function compressWeappImageIfNeeded(tempFilePath: string): Promise<string> {
  if (process.env.TARO_ENV !== 'weapp') return tempFilePath;

  let path = tempFilePath;
  let size = await getFileSize(path);
  if (size <= MAX_BYTES) return path;

  const qualities = [80, 65, 50, 40];
  for (const quality of qualities) {
    const res = await Taro.compressImage({ src: path, quality });
    path = res.tempFilePath;
    size = await getFileSize(path);
    if (size <= MAX_BYTES) return path;
  }

  if (size > MAX_BYTES) {
    throw new Error('图片压缩后仍超过 10MB，请换一张较小的图片');
  }
  return path;
}

async function getFileSize(filePath: string): Promise<number> {
  try {
    const info = await Taro.getFileInfo({ filePath });
    return typeof info.size === 'number' ? info.size : 0;
  } catch {
    return 0;
  }
}