markdown.js

var marked = require('marked');
var fs = require('fs');
var path = require('path');

// Synchronous highlighting with highlight.js
marked.setOptions({
  breaks: true,
  highlight: function (code, lang) {
    if (lang) {
      // highlight.js does not know html, but xml
      if (lang === 'html') lang = 'xml';
      code = require('highlight.js').highlight(lang, code).value;
    } else {
      code = require('highlight.js').highlightAuto(code).value;
    }

    // replace Derby template engine brackets in code examples
    code = code.replace(/\{\{/g, '{'); //actually {{
    code = code.replace(/\}\}/g, '}}');

    // new lines
    return code.replace(/\n/g, '<br>');
  }
});

// Generate html from # Header levels
function getNavbar(levels) {
  var html = '';
  var smallest = 5;
  for (var i = 0; i < levels.length; i++) {
    var level = levels[i][0];
    var link = levels[i][1];
    var header = levels[i][2];
    if (level < smallest) smallest = level;
    html += '<li><a href="#' + link + '">' + header + '</a>';
    if (i === levels.length - 1) {
      html += '</li>';
      for (var j = level; j > smallest; j--) {
        html += '</ul></li>';
      }
    } else {
      var nextLevel = levels[i + 1][0];
      if (level < nextLevel) {
        html += '<ul class="nav">';
      } else {
        html += '</li>';
      }
      if (level > nextLevel) {
        html += '</ul></li>';
      }
    }
  }
  return html;
}

// Escape string
function toLink (text) {
  return text.toLowerCase().replace(/[^\w]+/g, '-');
}

// Parse markdown file
function parseMarkdown(mdPath) {
  var lines = fs.readFileSync(mdPath, {encoding: 'utf8'}).toString().split('\n');
  if (lines[0].indexOf('# ') !== 0) {
    throw new Error('No # Header in ' + mdPath);
  }
  var name = lines[0].substr(2);
  var description = '';
  var startLine = 0;
  for (var i = 1; i < lines.length; i++) {
    if (lines[i].indexOf('##') !== 0) {
      description += lines[i];
    } else {
      startLine = i;
      break;
    }
  }

  var isCode = false;
  var file = '';
  var levels = [];
  for (var i = startLine; i < lines.length; i++) {
    var line = lines[i];
    if (line.indexOf('```') === 0) {
      isCode = !isCode;
    }
    if (line[0] === '#' & !isCode) {
      var level = line.indexOf(' ');
      var header = line.substr(level + 1);
      var link = toLink(header);
      levels.push([level, link, header]);
    }
    file += line + '\n';
  }

  return {
    file: file,
    levels: levels,
    link: toLink(name),
    name: name,
    description: description
  }
}

var openTag = '{{markdown}}';
var closeTag = '{{/markdown}}';

// Replace Markdown tags with html
function processTags (from) {
  var file = fs.readFileSync(from, {encoding: 'utf8'});
  while(true) {
    var startIndex = file.indexOf(openTag);
    if (startIndex === -1) break;
    var endIndex = file.indexOf(closeTag, startIndex);
    var startText = startIndex + openTag.length;
    var markdown = file.substring(startText, endIndex);
    var html = marked(markdown);
    file = file.replace(openTag + markdown + closeTag, html);
  }
  return file;
}

var mdDir = __dirname + '/md';
var appDir = __dirname + '/views/app';
var genDir = __dirname + '/views/gen';

if (!fs.existsSync(genDir)) {
  fs.mkdirSync(genDir);
}

var githubPath = 'https://github.com/vmakhaev/derby-site/edit/master/md';

// Replace tags in template with data from Markdown file
function processTemplate (mdPath, content, navbar) {
  var file = fs.readFileSync(appDir + '/template.html', {encoding: 'utf8'});
  var meta = parseMarkdown(mdDir + '/' + mdPath);
  file = file.replace('{{title}}', 'Derby | ' + meta.name);
  file = file.replace('{{editLink}}', githubPath + '/' + mdPath);
  file = file.replace('{{name}}', meta.name);
  file = file.replace('{{description}}', marked(meta.description));
  var navbar = navbar || getNavbar(meta.levels);
  file = file.replace('{{navbar}}', navbar);
  var content = content || marked(meta.file);
  file = file.replace('{{content}}', content);
  return file;
}


var importHtml = '';

function addToImport (name, ns) {
  if (ns) {
    importHtml += '<import: src="./' + name + '" ns="' + ns + '">\n';
  } else {
    importHtml += '<import: src="./' + name + '">\n';
  }
}

function processMarkdownDir (from, to, dirName) {
  var html = '<ul>';
  var fileNames = fs.readdirSync(from);
  for (var i = 0; i < fileNames.length; i++) {
    var fileName = fileNames[i];
    if (fileName === 'index.md') continue;
    var filePath = from + '/' + fileName;
    var meta = parseMarkdown(filePath);
    html += '<li><a href="/' + dirName + '/' + meta.link + '">' + meta.name + '</a></li>';

    var file = processTemplate(dirName + '/' + fileName);
    var name = path.basename(filePath, '.md');
    fs.writeFileSync(to + '/' + name + '.html', file);
    addToImport(dirName + '/' + name, dirName + ':' + name);
  }
  html += '</ul>';
  var file = processTemplate(dirName + '/index.md', html, ' ');
  fs.writeFileSync(to + '/index.html', file);
}

// Process /md dir
var fileNames = fs.readdirSync(mdDir);
for (var i = 0; i < fileNames.length; i++) {
  var fileName = fileNames[i];
  var filePath = mdDir + '/' + fileName;
  var stat = fs.statSync(filePath);
  if (stat.isDirectory()) {
    var to = genDir + '/' + fileName;
    if (!fs.existsSync(to)) {
      fs.mkdirSync(to);
    }
    processMarkdownDir(filePath, to, fileName);
    addToImport(fileName);

  } else {
    var name = path.basename(filePath, '.md');
    var file = processTemplate(fileName);
    fs.writeFileSync(genDir + '/' + name + '.html', file);
    addToImport(name);
  }
}

function processViewsDir (from, to) {
  var stat = fs.statSync(from);
  if (stat.isDirectory()) {
    if (!fs.existsSync(to)) {
      fs.mkdirSync(to);
    }
    var fileNames = fs.readdirSync(from);
    for (var i = 0; i < fileNames.length; i++) {
      var fileName = fileNames[i];
      processViewsDir(from + '/' + fileName, to + '/' + fileName);
    }
  } else {
    var file = processTags(from);
    if (from === appDir + '/index.html') {
      file = importHtml + file;
    }
    fs.writeFileSync(to, file);
  }
}

// Process /views dir
processViewsDir(appDir, genDir);