// ==UserScript==
// @name         电子课本下载
// @namespace    https://github.com/amakerlife
// @version      1.0
// @description  添加电子课本下载按钮
// @author       Makerlife
// @match        https://*.smartedu.cn/tchMaterial/detail*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=smartedu.cn
// @license      MIT
// @grant        none
// @downloadURL none
// ==/UserScript==

const pdfUrlRegExp = /\/pdf.pdf$/;
const originalFetch = window.fetch;
window.fetch = function() {
  return originalFetch.apply(this, arguments).then(response => {
    if (pdfUrlRegExp.test(response.url)) {
      console.log('捕获到 PDF 请求链接：' + response.url);
      localStorage.setItem('pdfUrl', response.url);
    }
    return response;
  });
};

const downloadBtn = document.createElement('div');
downloadBtn.classList.add('download-btn-wrapper');
downloadBtn.innerHTML = '<a href="#" class="download-link"><span class="download-icon"></span> Download PDF</a>';
downloadBtn.style.position = 'fixed';
downloadBtn.style.right = '20px';
downloadBtn.style.bottom = '20px';
downloadBtn.style.width = '50px';
downloadBtn.style.height = '50px';
downloadBtn.style.borderRadius = '25px';
downloadBtn.style.backgroundColor = 'blue';
downloadBtn.style.cursor = 'pointer';
downloadBtn.style.color = '#ffffff';

downloadBtn.addEventListener('click', function() {
  const pdfUrl = localStorage.getItem('pdfUrl');
  if (pdfUrl) {
    window.open(pdfUrl, '_blank');
  } else {
    console.log('未捕获到 PDF 请求链接');
  }
});

document.body.appendChild(downloadBtn);