ShogunPanda/chalkbars

/*
 * This file is part of the chalkbars npm package. Copyright (C) 2015 and above Shogun <shogun@cowtech.it>.
 * Licensed under the MIT license, which can be found at https://choosealicense.com/licenses/mit.
 */

const TO_RGB_TYPE = 5;
const BEGIN_SIZE = 5;
const FOOTER_MAX_SIZE = 3;

const handlebars = require("handlebars");
const chalk = require("chalk");
const functions = require("./functions");
const configuration = require("./configuration");

const renderTemplate = function(args, context){
  // Join arguments. If all the handlebars arguments for C* are unquoted, transform it as a single quoted argument.
  const sources = args.map(arg => { // eslint-disable-line arrow-body-style
    return typeof arg === "object" ? JSON.stringify(arg) : arg.toString();
  }).join("").replace(/\{\{(#C|B|E) ([^"].*?)\}\}/g, "{{$1 \"$2\"}}");

  // Return the handlebars compilation
  return handlebars.compile(sources)(context);
};

// --- Handlebars helpers ---
handlebars.registerHelper("C", function(){ // eslint-disable-line prefer-arrow-callback
  "use strict";

  const styles = Array.prototype.slice.call(arguments, 0);
  const options = styles.pop();
  let embedded = options.fn(this);
  let pipeline = chalk;

  functions.parseStyles(styles.join(" ")).split(/\s+/).forEach(style => { // Apply styles
    // Replace styles
    if(style.match(/^i#(\d{3})$/i)) // Replace 256 colors indexes
      embedded = functions.embedInColor(embedded, RegExp.$1, TO_RGB_TYPE, style[0] === "I");
    else if(style.match(/^x#(\d)(\d)(\d)$/i)) // Replace 256 colors codes
      embedded = functions.embedIn256Color(embedded, RegExp.$1, RegExp.$2, RegExp.$3, style[0] === "X");
    else if(style.match(/^h#([0-9A-F]{6})$/i)) // Replace 24 bit HEX colors codes
      embedded = functions.embedInHexColor(embedded, RegExp.$1, style[0] === "H");
    else if(typeof chalk[style] === "function") // Replace chalk colors
      pipeline = pipeline[style];
  });

  return typeof pipeline === "function" ? pipeline(embedded) : embedded;
});

handlebars.registerHelper("B", function(){
  "use strict";

  const tokens = Array.prototype.slice.call(arguments, 0, -1);
  const styles = tokens.pop();
  let embedded = tokens.join(" ");

  // If there was no argument, return an empty string
  if(!styles)
    return "";

  // If there was only an argument, it's both the style and the content
  if(!embedded)
    embedded = styles;

  while(embedded.length < BEGIN_SIZE)
    embedded = ` ${embedded}`;

  // Invoke the main helper for the content
  let inner = handlebars.helpers.C(styles, { // eslint-disable-line new-cap
    fn(){
      return embedded.toUpperCase();
    }
  });

  // If there is no style then make it bold
  if(inner.indexOf("\x1b") === -1)
    inner = chalk.bold(inner);

  // Surround with brackets
  return renderTemplate([configuration.openingBracket]) + inner + renderTemplate([configuration.closingBracket]);
});

handlebars.registerHelper("E", function(){
  "use strict";

  const tokens = Array.prototype.slice.call(arguments, 0, -1);
  const styles = tokens.pop();
  let embedded = tokens.join(" ");

  // If there was no argument, return an empty string
  if(!styles)
    return "";

  // If there was only an argument, it's both the style and the content
  if(!embedded)
    embedded = styles;

  // Make sure the text is at least 4 characters
  switch(embedded.length){
    case 1:
      embedded = ` ${embedded}  `;
      break;
    case 2:
      embedded = ` ${embedded} `;
      break;
    case FOOTER_MAX_SIZE:
      embedded = ` ${embedded}`;
      break;
  }

  // Invoke the main helper for the content
  let inner = handlebars.helpers.C(styles, { // eslint-disable-line new-cap
    fn(){
      return embedded.toUpperCase();
    }
  });

  // If there is no style then make it bold green
  if(inner.indexOf("\x1b") === -1)
    inner = chalk.bold.green(inner);

  // Surround with brackets
  const footer = renderTemplate([configuration.openingBracket]) + inner + renderTemplate([configuration.closingBracket]);
  const span = process.stdout.columns - chalk.stripColor(footer).length;
  return `\n\x1b[1A\x1b[${span}C${footer}`;
});

// --- Shortcuts
Object.keys(configuration.shortcuts).forEach(shortcut => {
  const value = configuration.shortcuts[shortcut];

  // Header
  handlebars.registerHelper(`B${shortcut}`, () => handlebars.helpers.B(value, {})); // eslint-disable-line new-cap

  // Footer
  handlebars.registerHelper(`E${shortcut}`, () => handlebars.helpers.E(value, {})); // eslint-disable-line new-cap
});

module.exports = {handlebars, chalk, renderTemplate};