WoW Gold parsing tool

gold.js

/* jshint undef: true, node: true, quotmark: single, indent: 2 */
'use strict';

/**
 * Zeke's World of Warcraft Gold Parsing Tool
 * https://gist.github.com/zekesonxx/78086f53a16cff33ed9e
 * Copyright (C) Zeke Sonxx 2014.
 * Licensed under the MIT License <choosealicense.com/licenses/mit>
 * @author Zeke Sonxx <github.com/zekesonxx>
 * @version 1.0.0
 */


var gold = {};

/**
 * Converts a copper amount to copper/silver/gold
 * Inverse: gold.asCopper
 * @param  {Number} amount Copper 
 * @return {Object}        {copper, silver, gold}
 * @public
 */
gold.convert = function(amount) {
  if (typeof amount !== 'number') {
    throw new TypeError('Expected number as input, got '+typeof amount);
  }
  var copper = amount;
  var silver = Math.floor(amount / 100);
  //  and
  var gold = Math.floor(silver / 100);

  if (silver !== 0) {
    // adjust the copper amount
    copper = copper - (silver*100);
  }
  if (gold !== 0) {
    silver = silver - (gold*100);
  }
  return {
    gold: gold,
    silver: silver,
    copper: copper
  };
};

/**
 * Take a gold/silver/copper object and return the value in copper
 * Inverse: gold.convert
 * @param  {Object} input {gold, silver, copper}
 * @return {Number}       Copper
 * @public
 */
gold.asCopper = function(input) {
  if (typeof input !== 'object') {
    throw new TypeError('Expected object as input, got '+typeof input);
  }
  var out = 0;
  out += input.gold * 100 * 100;
  out += input.silver * 100;
  out += input.copper;
  return out;
};

/**
 * Turns a copper value or object from gold.convert into a string
 * @param  {Object}  input Or number
 * @param  {Boolean} zeros Whether to display 0s reguardless (ex 0g 0s 5c)
 * @return {String}        Converted String
 * @public
 */
gold.stringify = function(input, zeros) {
  if (typeof input === 'number') {
    //allow people to pass a copper value directly
    input = gold.convert(input);
  }
  if (typeof input !== 'object') {
    //it should be a object now
    throw new TypeError('Expected object or number as first input, got '+typeof input);
  }
  if (zeros !== undefined && typeof zeros !== 'boolean') {
    throw new TypeError('Expected boolean or undefined as second input, got '+typeof zeros);
  }
  var out = [];
  // Gold
  if (input.gold !== 0 || zeros === true) {
    out.push((input.gold || 0) + 'g');
  }
  // Silver
  if (input.silver !== 0 || zeros === true || out.length === 1) {
    out.push((input.silver || 0) + 's');
  }
  // Copper
  if (input.copper !== 0 || zeros === true || out.length >= 1) {
    out.push((input.copper || 0) + 'c');
  }

  return out.join(' ');
};

/**
 * Take an input string like `5g 2s 10c` and return an object
 * @param  {String} input Input string
 * @return {Object}       {gold, silver, copper}
 * @throws {Error} Parse error, input is invalid
 * @public
 */
gold.parse = function(input) {
  if (typeof input !== 'string') {
    throw new TypeError('Expected string as input, got '+typeof input);
  }
  var expression = /(?:([0-9]{0,6})g\s)?(?:([0-9]{1,2})s\s)?([0-9]{1,2})c/;
  var result = expression.exec(input);
  if (result === null) {
    throw new Error('Parse error, input is invalid');
  }
  return {
    gold: parseInt(result[1]) || 0,
    silver: parseInt(result[2]) || 0,
    copper: parseInt(result[3])
  };
};

/**
 * Test suite
 * Errors if fails, silent if succeeded
 * @requires assert For assertion testing
 * @return {Null}
 * @private
 */
gold.__test = function() {
  var assert = require('assert');
  //gold.convert
  assert.equal(gold.convert(4).copper, 4,   'convert #1 failed');
  assert.equal(gold.convert(400).silver, 4, 'convert #2 failed');
  assert.equal(gold.convert(80000).gold, 8, 'convert #3 failed');
  assert.equal(gold.convert(80000).copper, 0, 'convert #4 failed');
  
  //gold.stringify
  assert.equal(gold.stringify(5524052), '552g 40s 52c', 'stringify #1 failed');
  assert.equal(gold.stringify(4, true), '0g 0s 4c', 'stringify #2 failed');

  //gold.parse
  assert.equal(gold.parse('50g 2s 10c').gold, 50, 'parse #1 failed');
  assert.equal(gold.parse('54c').copper, 54, 'parse #2 failed');

  //gold.asCopper
  assert.equal(gold.asCopper({ copper: 54, silver: 0, gold: 0 }), 54, 'asCopper #1 failed');
  assert.equal(gold.asCopper({ copper: 4, silver: 0, gold: 10 }), 100004, 'asCopper #2 failed');
};

gold.__test();

module.exports =  gold;