index.js

var _ = require("lodash");
var fs = require("fs");
var path = require("path");

var WEBSITE_TPL = _.template(fs.readFileSync(path.resolve(__dirname, "./assets/website.html")));
var EBOOK_TPL = _.template(fs.readFileSync(path.resolve(__dirname, "./assets/ebook.html")));

module.exports = {
    website: {
        assets: "./assets",
        js: [
            "ace/ace.js",
            "ace/theme-tomorrow.js",
            "ace/mode-javascript.js",
            "exercises.js"
        ],
        css: [
            "exercises.css"
        ]
    },
    ebook: {
        assets: "./assets",
        css: [
            "ebook.css"
        ]
    },
    blocks: {
        exercise: {
            parse: false,
            blocks: ["initial", "solution", "validation", "context"],
            process: function(blk) {
                var codes = {};

                _.each(blk.blocks, function(_blk) {
                    var src = _blk.kwargs.src;

                    var selection = src
                      ? /#L([0-9]+)(;)?\s*(L([0-9]+))?/.exec(src)
                      : null;

                    var body = src
                        ? fs.readFileSync(src.split("#")[0]).toString()
                        : _blk.body;

                    if (selection) {
                      const lines = body.split("\n");
                      const start = selection[1] - 1;
                      const end = selection[4] || (selection[2] ? lines.length : start + 1);
                      body = lines.slice(start, end).join("\n");
                    }

                    codes[_blk.name] = body.trim();
                });

                // Select appropriate template
                var tpl = (this.generator === 'website' ? WEBSITE_TPL : EBOOK_TPL);

                return tpl({
                    message: blk.body,
                    codes: codes
                });
            }
        }
    }
};