Scrapbox のバックアップ json から Markdown を作成

convertScrapboxToMarkdown.ts

import scrapboxData from '../scrapbox.json';
import fs from 'fs-extra';
import path from 'path';

const distPath = path.join(process.cwd(), 'dist');

async function main() {
  fs.mkdirp(distPath);

  scrapboxData.pages.forEach(page => {
    const fileName = page.title.replace(/\//g, '-');
    fs.writeFileSync(
      path.join(distPath, `${fileName}.md`),
      convertTable(convertCodeBlock(page.lines.slice(1))).map(line =>
        line
          // 見出し
          .replace(/^\[(\*{1,}) (.+)\]$/, (_, p1, p2) => `${'#'.repeat(6 - p1.length)} ${p2}\n`)
          // 斜体 + 太字
          .replace(/\[\/\* (.*)\]/, (_, p1) => ` ___${p1}___ `)
          // 斜体
          .replace(/\[\/ (.*)\]/, (_, p1) => ` _${p1}_ `)
          // 太字
          .replace(/\[\[(.*)\]\]/, (_, p1) => ` __${p1}__ `)
          // 太字（たぶん本来不正だが使っとる場所がありがち）
          .replace(/^\[\*{1} (.+)\]/, (_, p1) => `__${p1}__ `)
          // リンク
          .replace(/\[([^ ]*) (.+)\]/, (_, p1: string, p2: string) => p2.startsWith('http://') || p2.startsWith('https://') ? `[${p1}](${p2})` : `[${p2}](${p1})`)
          // リスト
          .replace(/^( +)/, (_, p1) => `${' '.repeat((p1.length - 1) * 2)}- `)
          // 引用
          .replace(/^(>+)([^ ])/, (_, __, p2) => `> ${p2}`)
      )
        .join('\n')
    );

    // code や table はかなり怪しいので plain も用意
    fs.writeFileSync(
      path.join(distPath, `${fileName}.plain.md`),
      page.lines.slice(1).join('\n')
    );
  });
}

function convertCodeBlock(lines: readonly string[]): readonly string[] {
  let inCodeBlock = false;

  return lines.map(line => {
    if (line.startsWith('code:')) {
      inCodeBlock = true;
      return line.replace(/^code:(.*)/, (_, p1) => `\`\`\`${p1}`)
    } else if (inCodeBlock && line === '') {
      inCodeBlock = false;
      return '```\n'
    } else if (inCodeBlock) {
      return line.substring(1);
    }

    return line;
  });
}

function convertTable(lines: readonly string[]): readonly string[] {
  let inTableBlock = false;
  let tableCellCount: number | undefined;

  return lines.map(line => {
    if (line.startsWith('table:')) {
      inTableBlock = true;
      return line.replace(/^table:(.*)/, (_, p1) => `__${p1}__\n\n`)
    } else if (inTableBlock && tableCellCount == null) {
      // 見出し
      tableCellCount = (line.match(/\t/g) ?? []).length + 1;
      return `${line.replace(/^ /, '| ').replace(/\t/g, ' | ')} |\n| ${'--- | '.repeat(tableCellCount)}`.trim();
    } else if (inTableBlock && line === '') {
      inTableBlock = false;
      tableCellCount = undefined;
    } else if (inTableBlock) {
      return line.replace(/^ /, '| ').replace(/\t/g, ' | ').replace(/ ?$/g, ' |');
    }

    return line;
  });
}

main();