chatgpt-export-markdown.user.js

// ==UserScript==
// @name          ChatGPT save to Markdown button
// @author        spion, avosirenfal
// @description   Adds an export button for exporting the doc to markdown
// @namespace     chatgpt
// @version       1.0.0
// @match         https://chat.openai.com/*
// @grant         none
// @run-at        document-start
// ==/UserScript==

// Inspired by https://github.com/avosirenfal/chatgpt-export/blob/main/chatgpt-export.user.js

(function () {
  'use strict';

  const turndownModule = import('https://cdn.skypack.dev/turndown');


  const Characters = {
    Me: 'User',
    Gpt: 'ChatGPT'
  }

  const callback = function (_mutationsList, _observer) {
    const nav = document.querySelector("nav");

    if (nav.querySelector("#custom_save_button")) {
      return;
    }


    const el = nav.lastElementChild.cloneNode(false);
    el.id = 'custom_save_button';
    el.innerHTML = "Export Markdown";

    el.onclick = async function () {
      const turndown = (await turndownModule).default;
      const td = new turndown();

      td.addRule('fencedCodeBlock', {
        filter: function (node, options) {
          return (
            // options.codeBlockStyle === 'fenced' &&
            node.nodeName === 'PRE' &&
            node.querySelector('code.hljs') != null
          )
        },

        replacement: function (content, node, options) {
          let codeBlock = node.querySelector('code.hljs');
          var className = codeBlock.getAttribute('class') || ''
          var language = (className.match(/language-(\S+)/) || [null, ''])[1]
          return `\n\n${'```'}${language}\n${codeBlock.textContent}\n${'```'}\n\n`;
        }
      })

      const html2markdown = html => td.turndown(html);

      const markdownLink = document.createElement('a');
      let firstConversationItem = null;

      let conversation = `# ${document.title}\n\n`
      let currentCharacter = Characters.Me;

      for (let item of Array.from(document.querySelectorAll('div:has(img) + div .items-start'))) {
        firstConversationItem = item;
        conversation += `### ${currentCharacter}\n\n`

        if (item.querySelector('.markdown')) {
          let gptHtml = item.querySelector('.markdown').innerHTML;
          let gptMarkdown = html2markdown(gptHtml);

          // Remove "Copy code" lines.

          // Todo: convert small code blocks to larger code blocks with language
          gptMarkdown = gptMarkdown.split("\n").filter(l => !/^[a-z]*Copy code$/.test(l)).join("\n");
          conversation += gptMarkdown;
        }
        else {
          conversation += item.innerText;
        }
        conversation += "\n\n";

        if (currentCharacter == Characters.Me) {
          currentCharacter = Characters.Gpt
        }
        else {
          currentCharacter = Characters.Me
        }
      }

      if (firstConversationItem === null) {
        alert("Failed to get text for the items. The conversation is empty, or the CSS selector is no longer correct");
        return;
      }

      markdownLink.href = URL.createObjectURL(new Blob([conversation], {
        type: 'text/markdown'
      }));

      markdownLink.download = `GPT Conversation - ${document.title}.md`;
      document.body.appendChild(markdownLink);
      markdownLink.click();
      document.body.removeChild(markdownLink);
      URL.revokeObjectURL(markdownLink.href);
    }

    nav.appendChild(el);
  };

  window.addEventListener('load', (event) => {
    const observer = new MutationObserver(callback);
    observer.observe(document.querySelector('body'), { attributes: true, childList: true, subtree: true });
  });
})();