import { isHttpImageUrl } from '@dukang/weixin-sdk';
import { toastSuccess } from './toast';
import { isWechatEnv, weixinSdk } from './weixin';

export { isHttpImageUrl };

export function blobToDataUrl(blob: Blob): Promise<string> {
  return new Promise((resolve, reject) => {
    const reader = new FileReader();
    reader.onload = () => resolve(String(reader.result || ''));
    reader.onerror = () => reject(new Error('读取图片失败'));
    reader.readAsDataURL(blob);
  });
}

/**
 * 微信内用 previewImage 打开可公网访问的图片，用户长按即可保存。
 * blob / data URL 不能走该接口。
 */
export async function previewSaveableImage(url: string): Promise<boolean> {
  const href = url.trim();
  if (!isWechatEnv() || !isHttpImageUrl(href)) return false;
  try {
    await weixinSdk.previewImage(href);
    toastSuccess('请长按图片保存到相册');
    return true;
  } catch {
    toastSuccess('请长按上方图片保存到相册');
    return false;
  }
}