import * as path from 'path';

import { fetchHtml } from './fetch-html';

export interface WebMetaInfo {
  title?: string;
  description?: string;
  keyword?: string;
  favicon?: string;
  image?: string;
  url: string;
}

export const fetchWebMetaInfo = async (
  webUrl: string,
): Promise<WebMetaInfo | undefined> => {
  try {
    const $ = await fetchHtml(webUrl);
    if (!$) return;

    const title = $('title').text();
    let description = $(
      'meta[name*="description"], meta[property*="og:description"]',
    ).attr('content');

    // https://ogp.me/
    // og 对 seo 的影响：https://cloud.tencent.com/developer/article/1617791
    const image = $(
      'meta[property*="og:image"], meta[property*="og:image:url"], meta[property*="og:image:secure_url"]',
    ).attr('content');
    const keyword = $('meta[name*="keywords"]').attr('content');

    const url = new URL(webUrl);

    let favicon = $('link[rel*="icon"]').attr('href');
    if (favicon) {
      if (!/^((https?:\/\/)|(data:))/.test(favicon)) {
        if (favicon.startsWith('/')) {
          favicon = path.join(url.origin, favicon);
        }

        if (favicon.startsWith('.')) {
          favicon = path.join(url.origin, url.pathname, '../', favicon);
        }
      }
    } else {
      favicon = url.origin + '/favicon.ico';
    }

    if (!description) {
      description = $('body').text().slice(0, 100);
    }

    return {
      url: webUrl,
      title,
      description,
      keyword,
      favicon,
      image,
    };
  } catch (error) {
    console.log(error);
    return;
  }
};