[for Metalsmith] Converting Jade content

converting-jade-for-metalsmith.js

/*
 * Based on metalsmith-jade
 * https://github.com/MaxBareiss/metalsmith-jade
 * License MIT (c) 2014 Max Bareiss
 * */

/*
 if you need output non-HTML file (like xml),
 you have to add `ext` metadata key and  extension-name string value (like 'xml') to that content.

 Exmaple:
   - title: 'My blog RSS feed'
   - ext: 'xml'
   and some metadata ...
 */

/*
 this jade converter have `:escape` filter

 Example:
   pre
     code
       :escape
         <h1>Escaped Text</h1>
 */

var basename = require('path').basename;
var join = require('path').join;
var dirname = require('path').dirname;
var extname = require('path').extname;

var jade = require('jade');
var jade_runtime = require('../node_modules/jade/lib/runtime');
var jade_filters = require('../node_modules/jade/lib/filters');
var jade_inline = require('../node_modules/jade/lib/inline-tags');

['ruby', 'rt', 'rb', 'rtc', 'var'].forEach(function (v, i) {
  jade_inline.push(v);
});

jade_filters.escape = function (text) {
  return jade_runtime.escape(text);
};

module.exports = function (options) {

  options = options || {};

  return function (files, metalsmith, done) {
    setImmediate(done);
    Object.keys(files).forEach(function (file) {
      //console.log('checking file: %s', file);
      if (!isJade(file)) {
        console.log('%s is not Jade file', file);
        return;
      }
      var data = files[file];
      var dir = dirname(file);
      var outputFile = basename(file, extname(file)) + '.';
      outputFile += data.ext ? data.ext.replace(/^\./, '') : 'html';
      if ('.' != dir) {
        outputFile = dir + '/' + outputFile;
      }
      console.log('converting file: %s -> ' + outputFile, file);
      options.filename = join(metalsmith.dir, metalsmith._src, file);
      var str = jade.compile(data.contents.toString(), options)(options.locals);
      data.contents = new Buffer(str);
      delete files[file];
      files[outputFile] = data;
    });
  };
};

function isJade(file) {
  return /\.jade/.test(extname(file));
}