markdown grabber
// ==UserScript==
// @name Markdown Grabber
// @namespace http://tampermonkey.net/
// @version 1.1
// @description markdown grabber
// @author 5ec1cff
// @match *://*/*
// @license AGPL
// @grant unsafeWindow
// @grant GM_registerMenuCommand
// @grant GM_xmlhttpRequest
// @connect *
// ==/UserScript==
// 2021.12.24 Fri: 修正
// 2022.03.15 Tue: 增加下载图片支持（默认启用）
// 2023.03.01 Wed: 支持 xz.aliyun.cn ；下载图片附带 Referer
// 2025.06.30 Mon: 兼容 bbs.kanxue.com ，支持代码，支持解密链接
(function () {
'use strict';
if (window.top !== window) return; // 阻止在 iframe 启用
const downloadPics = true;
const picMap = new Map();
const console = unsafeWindow.console.context();
function decodeKanxueUrl(s) {
let str = s;
try {
// 检查是否已经是解密后的URL格式
if (str.includes('http://') || str.includes('https://') || str.includes('www.')) {
return str;
}
// 1. 移除salt
const encrypted = str.slice(3);
// 2. 定义替换规则的反向映射
const replacePairs = {
'K9': 'a', 'L8': 'b', 'M7': 'c',
'N6': 'd', 'P5': 'e', 'Q4': 'f',
'R3': 'g', 'S2': 'h', 'T1': 'i',
'U0': 'j', 'V1': 'k', 'W2': 'l',
'X3': 'm', 'Y4': 'n', 'Z5': 'o',
'A6': 'p', 'B7': 'q', 'C8': 'r',
'D9': 's', 'E0': 't', 'F1': 'u',
'G2': 'v', 'H3': 'w', 'I4': 'x',
'J5': 'y', 'K6': 'z',
'l9': 'A', 'm8': 'B', 'n7': 'C',
'o6': 'D', 'p5': 'E', 'q4': 'F',
'r3': 'G', 's2': 'H', 't1': 'I',
'u0': 'J', 'v1': 'K', 'w2': 'L',
'x3': 'M', 'y4': 'N', 'z5': 'O',
'a6': 'P', 'b7': 'Q', 'c8': 'R',
'd9': 'S', 'e0': 'T', 'f1': 'U',
'g2': 'V', 'h3': 'W', 'i4': 'X',
'j5': 'Y', 'k6': 'Z',
'@1': '0', '#2': '1', '$3': '2',
'%4': '3', '^5': '4', '&6': '5',
'*7': '6', '(8': '7', ')9': '8',
'!0': '9', '-_': '+', '|~': '/',
'`.': '='
};
// 3. 按长度排序替换规则
const sortedPairs = Object.entries(replacePairs)
.sort((a, b) => b[0].length - a[0].length);
// 4. 执行替换
let base64 = encrypted;
for (const [pattern, replacement] of sortedPairs) {
base64 = base64.split(pattern).join(replacement);
}
// 5. 补全base64字符串的等号
while (base64.length % 4) {
base64 += '=';
}
// 6. 清理非法字符
base64 = base64.replace(/[^A-Za-z0-9+/=]/g, '');
// 7. base64解码
const decoded = atob(base64);
s = decoded;
} catch (e) {
console.log('decodeKanxueUrl', e);
return str; // 如果解密失败，返回原始字符串
}
s = s.replace(/_/g, "%");
s = decodeURIComponent(s);
return s;
}
function getPictureKey(url) {
return url;
}
function getPicture(url) {
const key = getPictureKey(url);
if (picMap.get(url) == null) {
picMap.set(url,
new Promise((rs, rj) => {
if (!downloadPics || !url?.startsWith("http")) {
rs([key, url]);
return;
}
GM_xmlhttpRequest({
url: url,
headers: { Referer: location.href },
responseType: "blob",
onload(r) {
const fr = new FileReader();
fr.onloadend = () => {
console.log('load done:', url);
rs([key, fr.result]);
}
fr.onerror = (e) => {
rj(e);
}
fr.readAsDataURL(r.response);
},
onerror(e) {
rj(e);
},
onabort(e) {
rj(e);
}
})
})
);
}
return key;
}
function parseSimpleStyle(e) {
let r = '';
switch (e.tagName.toLowerCase()) {
case 'b':
case 'strong':
r += `**${parseSingleLine(e)}**`;
break;
case 'i':
case 'em':
r += `*${parseSingleLine(e)}*`;
break;
case 's':
case 'strike':
r += `~~${parseSingleLine(e)}~~`;
break;
case 'a': {
if (e.href) {
let href = e.getAttribute('href');
if (href.indexOf('elink@') !== -1) {
href = decodeKanxueUrl(href.substr(6));
}
r += `[${parseSingleLine(e)}](${href})`;
}
break;
}
case 'code':
r += `\`${e.innerText}\``;
break;
case 'img':
r += `\n![][${getPicture(e.src)}]\n`;
break;
default:
r += parseSingleLine(e);
}
return r;
}
function parseSingleLine(element) {
if (element instanceof Text) return element.data.trim();
let r = '';
if (element instanceof HTMLElement) {
for (let e of element.childNodes) {
if (e instanceof Text) r += e.data;
if (!(e instanceof HTMLElement)) continue;
r += parseSimpleStyle(e);
}
}
return r.trim();
}
function isSingleLine(node) {
return !node.querySelector('p,ul,ol,br');
}
function parseNode(element) {
let lines = [], singleLine = null;
if (element instanceof HTMLElement) {
for (let e of element.childNodes) {
if (!(e instanceof HTMLElement) && !(e instanceof Text)) continue;
let tagName;
if (e instanceof Text) {
tagName = 'TEXT';
} else {
tagName = e.tagName.toLowerCase();
}
switch (tagName) {
case 'TEXT':
case 'a':
case 'b':
case 'strong':
case 'i':
case 'em':
case 's':
case 'strike':
case 'a':
case 'code': {
if (singleLine == null) singleLine = '';
if (tagName == 'TEXT') {
singleLine += e.data.trim();
}
else {
singleLine += parseSimpleStyle(e);
}
continue;
}
default:
if (singleLine != null) {
lines.push(singleLine);
singleLine = null;
}
}
switch (tagName) {
// ignores
case 'button':
case 'style':
case 'header':
case 'script':
continue;
case 'p':
lines.push(parseSingleLine(e) + '\n');
break;
case 'br':
lines.push('\n');
break;
case 'ul':
case 'ol': {
lines.push('');
let is_order = tagName == 'ol',
j = 1;
for (let item of e.childNodes) {
let pref = is_order ? `${j}. ` : `- `;
if (item instanceof HTMLLIElement) {
if (!isSingleLine(item)) {
let item_lines = parseNode(item);
for (let i = 0; i < item_lines.length; i++) {
const l = item_lines[i].trim()
if (l) {
lines.push(`${i==0?pref:' '}${item_lines[i]}`);
}
}
} else {
lines.push(`${pref}${parseSingleLine(item)}`);
}
j++;
}
}
lines.push('');
break;
}
case 'pre': {
// debugger
lines.push('```');
lines.push(...(e.querySelector('code') || e).innerText.trim().split('\n'));
lines.push('```');
break;
}
case 'blockquote': {
lines.push('');
let item_lines = parseNode(e);
for (let i = 0; i < item_lines.length; i++) {
lines.push(`> ${item_lines[i]}`);
}
lines.push('');
break;
}
case 'table': {
if (e.classList.contains('syntaxhighlighter')) {
let content = e.querySelector('.code');
if (content) {
let lang = Array.from(e.classList).filter(x=>x!='syntaxhighlighter')[0] || '';
lines.push('```' + lang);
lines.push(...content.innerText.trim().split('\n'));
lines.push('```');
break;
}
}
lines.push('');
let head = e.querySelector('thead');
if (!head) {
console.warn('unknown table!');
// resolve body as normal tag
let body;
if (body = e.querySelector('tbody')) {
lines.push(...parseNode(body));
}
continue;
}
let head_line = '|',
sep_line = '|';
for (let h of head.querySelectorAll('th')) {
head_line += `${parseSingleLine(h)}|`;
sep_line += `--|`
}
lines.push(head_line);
lines.push(sep_line);
let body = e.querySelector('tbody');
for (let b of body.querySelectorAll('tr')) {
let line = '|';
for (let d of b.querySelectorAll('td')) {
line += `${parseSingleLine(d)}|`;
}
lines.push(line);
}
lines.push('');
break;
}
case 'hr':
lines.push('\n---\n');
break;
case 'img':
lines.push(`\n![][${getPicture(e.src)}]\n`);
break;
case 'figure': {
if (e.classList.contains('highlight')) {
let lang = e.classList[1] || '';
let code = e.querySelector('td.code pre');
if (code != null) {
lines.push('```' + lang);
lines.push(...code.innerText.trim().split('\n'));
lines.push('```');
break;
}
}
// fallthrough
}
case 'td': {
if (e.classList.contains('gutter')) continue;
// fallthrough
}
default: {
let r;
if (r = tagName.match(/h(\d+)/)) {
lines.push(`\n${'#'.repeat(Number(r[1]))} ${parseSingleLine(e)} \n`);
} else {
lines.splice(lines.length, 0, ...parseNode(e));
}
}
}
}
if (singleLine != null) lines.push(singleLine);
}
return lines;
}
function findArticle() {
let article = document.body.querySelector('article');
if (article) return article;
article = document.body.querySelector('div.markdown-body,div.mod-content');
if (article) return article;
article = document.body.querySelector('div.message_md_type'); // kanxue
if (article) return article;
let maxChild = 0, node = null;
for (let n of document.querySelectorAll('h1')) {
if (n.parentNode && n.parentNode.childElementCount >= maxChild) {
node = n.parentNode;
}
}
return node;
}
async function html2MD() {
let article = findArticle();
let title = document.querySelector('h1');
let r = '';
if (title) {
r += `# ${parseSingleLine(title)}`;
} else {
r += `# ${document.title}`;
}
r += `\n${location.href}\n\n`;
r += await nodeToMD(article);
return r;
}
async function nodeToMD(node) {
picMap.clear();
let r = '';
let lines = parseNode(node);
for (let l of lines) {
r += `${l}\n`;
}
let pics = await Promise.race([
Promise.all(picMap.values()),
new Promise((_, rj) => {
console.log("waiting 10s for downloading pictures...", picMap.size);
setTimeout(() => { rj('time out!'); }, 10000)
})
]);
r += '\n';
for (let [key, url] of pics) {
r += `[${key}]:${url}\n`;
}
return r;
}
unsafeWindow.md = nodeToMD;
// unsafeWindow.__xhr = GM_xmlhttpRequest;
// unsafeWindow._getpic = getPicture
async function onClick() {
let url = URL.createObjectURL(new Blob([await html2MD()], { type: 'text/plain' }));
let a = document.createElement('a');
a.download = `${document.title}.md`;
a.href = url;
document.body.append(a);
a.click();
a.remove();
}
GM_registerMenuCommand('下载 Markdown', () => {
onClick();
})
})();