jenova/lib/expand.js

A game of life module that is intended to work both in a server side and client side environment.

'use strict';

var LZUTF8 = require('lzutf8');

/**
 * Given a compressed value, return a board array
 * @param {String/Object} compressed - compressed game of life board
 * @param {Number} width - width of our matrix
 * @returns {Matrix} Decompressed game of life matrix
 */
function expand(compressed, width) {

  var compressedString = compressed,
    decompressedObject = {
      inputEncoding: 'BinaryString'
    };

  // Check to see if we passed in the compressed object (instead of just a string)
  if (compressed.compressed) {
    width = compressed.width;
    compressedString = compressed.compressed;
  }

  var decompressed = LZUTF8.decompress(compressedString, decompressedObject),

  // 001001 to ['0','0','1','0','0','1']
    decompressedToArray = decompressed.split(''),

  // Map ['1'] to [1], then reduce to a matrix [ [1] ]
    result = decompressedToArray.map(function(cell) {
      return parseInt(cell, 10);
    }).reduce(function(memo, cell, index) {
      if (index % width === 0) {
        memo.push([]);
      }
      memo[memo.length - 1].push(cell);
      return memo;
    }, []);

  return result;
}

module.exports = expand;