email script

const path = require('path');
const fs = require('fs-extra');
const sassExtract = require('sass-extract');
const Handlebars = require('handlebars');
const juice = require('juice');

const templatesPath = path.resolve(__dirname, '../templates/');
const partialsPath = path.resolve(__dirname, '../components/');

const templateNames = fs.readdirSync(templatesPath);
const partialNames = fs.readdirSync(partialsPath);

let cssSource = '';

Handlebars.registerHelper('ifCond', function (v1, operator, v2, options) {

  switch (operator) {
    case '==':
      return (v1 == v2) ? options.fn(this) : options.inverse(this);
    case '===':
      return (v1 === v2) ? options.fn(this) : options.inverse(this);
    case '!=':
      return (v1 != v2) ? options.fn(this) : options.inverse(this);
    case '!==':
      return (v1 !== v2) ? options.fn(this) : options.inverse(this);
    case '<':
      return (v1 < v2) ? options.fn(this) : options.inverse(this);
    case '<=':
      return (v1 <= v2) ? options.fn(this) : options.inverse(this);
    case '>':
      return (v1 > v2) ? options.fn(this) : options.inverse(this);
    case '>=':
      return (v1 >= v2) ? options.fn(this) : options.inverse(this);
    case '&&':
      return (v1 && v2) ? options.fn(this) : options.inverse(this);
    case '||':
      return (v1 || v2) ? options.fn(this) : options.inverse(this);
    default:
      return options.inverse(this);
  }
});

Handlebars.registerHelper('current-year', function () {
  return new Date().getFullYear();
});

partialNames.forEach(partialName => {
  // Register all partials
  const partialPath = path.resolve(partialsPath, `${partialName}/${partialName}.hbs`);
  const templateSource = fs.readFileSync(partialPath);

  Handlebars.registerPartial(partialName, templateSource.toString());


  // Save partial css
  const cssPath = path.resolve(partialsPath, `${partialName}/${partialName}.scss`);

  if (!fs.existsSync(cssPath)) return;

  const cssRendered = sassExtract.renderSync({
    file: cssPath,
  });

  cssSource += `${cssRendered.css.toString()}\n`;
});

// Generate output html using hbs template, saved css and json data files
templateNames.forEach(templateName => {
  const templatePath = path.resolve(templatesPath, `${templateName}/template.hbs`);
  const dataPath = path.resolve(templatesPath, `${templateName}/data`);
  const templateSource = fs.readFileSync(templatePath);
  const dataNames = fs.readdirSync(dataPath);

  dataNames.forEach(filename => {
    const jsonName = filename.split('.')[0];
    const outputPath = path.resolve(__dirname, `../../dist/emails/${templateName}/${jsonName}.html`);
    const jsonPath = path.resolve(dataPath, filename);
    const json = fs.readFileSync(jsonPath);
    const template = Handlebars.compile(templateSource.toString());

    const data = JSON.parse(json);
    data['styles'] = cssSource;

    const outputHTML = template(data);
    const output = juice(`${outputHTML}`);

    fs.outputFile(outputPath, output);
  });
});