// ==UserScript==
// @name         国家职业技能标准下载
// @namespace    http://tampermonkey.net/
// @version      0.1.1
// @description  国家职业技能标准下载
// @author       Shuai Ma
// @match        http://biaozhun.osta.org.cn/pdfview.html?code=*
// @grant        GM_notification
// ==/UserScript==

(function() {
    'use strict';

    // 获取请求链接中的code值
    function getCodeFromUrl() {
        const url = window.location.href;
        const codeRegex = /code=(\d+)/;
        const match = url.match(codeRegex);
        return match ? match[1] : '';
    }

    // 拼接请求链接和code值
    function buildApiUrl(code) {
        return `http://biaozhun.osta.org.cn/api/v1/profession/get/${code}`;
    }

    // 发送请求并获取返回的data
    async function fetchData(url) {
        const response = await fetch(url);
        const data = await response.json();
        return data;
    }

    // 对data进行base64解密
    function base64Decode(data) {
        const decodedData = atob(data);
        const byteArray = new Uint8Array(decodedData.length);
        for (let i = 0; i < decodedData.length; i++) {
            byteArray[i] = decodedData.charCodeAt(i);
        }
        return byteArray;
    }

    // 生成pdf文件并下载
    function downloadPdf(data, fileName) {
        const blob = new Blob([data], { type: 'application/pdf' });
        const link = document.createElement('a');
        link.href = URL.createObjectURL(blob);
        link.download = fileName;
        link.click();
    }

    // 主函数
    async function main() {
        const code = getCodeFromUrl();
        const apiUrl = buildApiUrl(code);
        const data = await fetchData(apiUrl);
        if(data.code == "0"){
            GM_notification({
                title: "职业标准系统",
                text: "下载PDF文件",
                onclick: function () {
                    // 获取iframe元素
                    var iframe = document.getElementById('pdfFrame');
                    // 获取iframe中的指定元素
                    var targetElement = iframe.contentWindow.document.querySelector("#viewer > div:nth-child(1) > div.textLayer > span:nth-child(24)");
                    // 获取元素的值
                    var value = targetElement.innerHTML;
                    console.log(value); 
                    const decodedData = base64Decode(data.data);
                    downloadPdf(decodedData, value +'.pdf');
                }
            })
        }
    }

    main();
})();