pattern.js

/*
 * pattern.js
 *
 * Utilities to parse str pattern and return info
 *
 */


define(function () {


// Define module
var pattern = {};

// Match information
var DELIM_SIZE = 4;

// Our regex used to parse
var regexp  = new RegExp('{{([^}]+)}}', 'g');

//
// Helper method to parse pattern str
//
var getMatches = function (pattern) {
  // Populate array of matches
  var matches = [],
      match;
  while(match = regexp.exec(pattern)) {
    matches.push(match);
  }

  return matches;
};

//
// Create an object holding all formatted characters
// with corresponding positions
//
pattern.parse = function (pattern) {
  // Our obj to populate
  var info = { inpts: {}, chars: {} };

  // Pattern information
  var matches = getMatches(pattern),
      pLength = pattern.length;

  // Counters
  var mCount = 0,
      iCount = 0,
      i = 0;

  // Add inpts, move to end of match, and process
  var processMatch = function (val) {
    var valLength = val.length;
    for (var j = 0; j < valLength; j++) {
      info.inpts[iCount] = val.charAt(j);
      iCount++;
    }
    mCount ++;
    i += (val.length + DELIM_SIZE - 1);
  };

  // Process match or add chars
  for (i; i < pLength; i++) {
    if (mCount < matches.length && i === matches[mCount].index) {
      processMatch(matches[mCount][1]);
    } else {
      info.chars[i - (mCount * DELIM_SIZE)] = pattern.charAt(i);
    }
  }

  // Set mLength and return
  info.mLength = i - (mCount * DELIM_SIZE);
  return info;
};


// Expose
return pattern;


});