Script to split Markdown files

markdown-file-splitter.js

const fs = require('fs');
const PATH = process.argv[2] || __dirname;
const LEVEL = parseInt(process.argv[3] || 1);
const TARGET = process.argv[4];
const DELETE = process.argv[5];

fs.readdirSync(PATH)
    .filter(isOptionalTarget)
    .filter(isMarkdownFile)
    .map(readFile)
    .map(splitContent)
    .map(doCreateFolders)
    .map(doCreateFiles)
    .map(doOptionalCleanupFiles)
    .map(log);

function readFile(filename) {
    const content = fs.readFileSync(`${PATH}/${filename}`).toString();
    const dirname = filename.replace(/^_/, '').replace('.md', '');
    return { filename, dirname, content };
}

function splitContent(data) {
    const re = RegExp(`\n\n(#{${LEVEL}} .*\n)`, 'g');
    const markup = data.content.replace(re, match => {
        return '-->slice<--' + match.trim();
    });

    const sections = markup.split('-->slice<--')
        .map(text => text.trim())
        .map(text => ({
            title: text
                .slice(0, text.indexOf('\n'))
                .replace(/#+\s/, '')
                .replace(/\s/g, '_')
                .toLowerCase(),
            text
        }));

    return Object.assign(data, { sections });
}

fucntion isOptionalTarget(filename) {
    return !TARGET || filename === TARGET;
}

function isMarkdownFile(filename) {
    return /\.md$/.test(filename);
}

function doCreateFolders(data) {
    fs.mkdirSync(`${PATH}/${data.dirname}`);

    return data;
}

function doCreateFiles(data) {
    data.sections.forEach(section => {
        const title = `_${section.title}.md`;
        fs.writeFileSync(`${PATH}/${data.dirname}/${title}`, section.text);
    });

    return data;
}

function doOptionalCleanupFiles(data) {
    if (DELETE) {
        fs.unlinkSync(`${PATH}/${data.filename}`);
    }
    return data;
}

function log(data) {
    console.log(data.dirname);
    data.sections.forEach(section => {
        console.log(data.dirname + '/' + section.title);
    })
}