(function(root, factory) {
  if (typeof define === 'function' && define.amd) {
    define(factory);
  } else if (typeof exports === 'object') {
    module.exports = factory();
  } else {
    root.VMasker = factory();
  }
}(this, function() {
  var DIGIT = "9",
      ALPHA = "A",
      ALPHANUM = "S",
      BY_PASS_KEYS = [9, 16, 17, 18, 36, 37, 38, 39, 40, 91, 92, 93],
      isAllowedKeyCode = function(keyCode) {
        for (var i = 0, len = BY_PASS_KEYS.length; i < len; i++) {
          if (keyCode == BY_PASS_KEYS[i]) {
            return false;
          }
        }
        return true;
      },
      mergeMoneyOptions = function(opts) {
        opts = opts || {};
        opts = {
          precision: opts.hasOwnProperty("precision") ? opts.precision : 2,
          separator: opts.separator || ",",
          delimiter: opts.delimiter || ".",
          unit: opts.unit && (opts.unit.replace(/[\s]/g,'') + " ") || "",
          suffixUnit: opts.suffixUnit && (" " + opts.suffixUnit.replace(/[\s]/g,'')) || "",
          zeroCents: opts.zeroCents,
          lastOutput: opts.lastOutput
        };
        opts.moneyPrecision = opts.zeroCents ? 0 : opts.precision;
        return opts;
      },
      // Fill wildcards past index in output with placeholder
      addPlaceholdersToOutput = function(output, index, placeholder) {
        for (; index < output.length; index++) {
          if(output[index] === DIGIT || output[index] === ALPHA || output[index] === ALPHANUM) {
            output[index] = placeholder;
          }
        }
        return output;
      }
  ;

  var VanillaMasker = function(elements) {
    this.elements = elements;
  };

  VanillaMasker.prototype.unbindElementToMask = function() {
    for (var i = 0, len = this.elements.length; i < len; i++) {
      this.elements[i].lastOutput = "";
      this.elements[i].onkeyup = false;
      this.elements[i].onkeydown = false;

      if (this.elements[i].value.length) {
        this.elements[i].value = this.elements[i].value.replace(/\D/g, '');
      }
    }
  };

  VanillaMasker.prototype.bindElementToMask = function(maskFunction) {
    var that = this,
        onType = function(e) {
          e = e || window.event;
          var source = e.target || e.srcElement;

          if (isAllowedKeyCode(e.keyCode)) {
            setTimeout(function() {
              that.opts.lastOutput = source.lastOutput;
              source.value = VMasker[maskFunction](source.value, that.opts);
              source.lastOutput = source.value;
              if (source.setSelectionRange && that.opts.suffixUnit) {
                source.setSelectionRange(source.value.length, (source.value.length - that.opts.suffixUnit.length));
              }
            }, 0);
          }
        }
    ;
    for (var i = 0, len = this.elements.length; i < len; i++) {
      this.elements[i].lastOutput = "";
      this.elements[i].onkeyup = onType;
      if (this.elements[i].value.length) {
        this.elements[i].value = VMasker[maskFunction](this.elements[i].value, this.opts);
      }
    }
  };

  VanillaMasker.prototype.maskMoney = function(opts) {
    this.opts = mergeMoneyOptions(opts);
    this.bindElementToMask("toMoney");
  };

  VanillaMasker.prototype.maskNumber = function() {
    this.opts = {};
    this.bindElementToMask("toNumber");
  };
  
  VanillaMasker.prototype.maskAlphaNum = function() {
    this.opts = {};
    this.bindElementToMask("toAlphaNumeric");
  };

  VanillaMasker.prototype.maskPattern = function(pattern) {
    this.opts = {pattern: pattern};
    this.bindElementToMask("toPattern");
  };

  VanillaMasker.prototype.unMask = function() {
    this.unbindElementToMask();
  };

  var VMasker = function(el) {
    if (!el) {
      throw new Error("VanillaMasker: There is no element to bind.");
    }
    var elements = ("length" in el) ? (el.length ? el : []) : [el];
    return new VanillaMasker(elements);
  };

  VMasker.toMoney = function(value, opts) {
    opts = mergeMoneyOptions(opts);
    if (opts.zeroCents) {
      opts.lastOutput = opts.lastOutput || "";
      var zeroMatcher = ("("+ opts.separator +"[0]{0,"+ opts.precision +"})"),
          zeroRegExp = new RegExp(zeroMatcher, "g"),
          digitsLength = value.toString().replace(/[\D]/g, "").length || 0,
          lastDigitLength = opts.lastOutput.toString().replace(/[\D]/g, "").length || 0
      ;
      value = value.toString().replace(zeroRegExp, "");
      if (digitsLength < lastDigitLength) {
        value = value.slice(0, value.length - 1);
      }
    }
    var number = value.toString().replace(/[\D]/g, ""),
        clearDelimiter = new RegExp("^(0|\\"+ opts.delimiter +")"),
        clearSeparator = new RegExp("(\\"+ opts.separator +")$"),
        money = number.substr(0, number.length - opts.moneyPrecision),
        masked = money.substr(0, money.length % 3),
        cents = new Array(opts.precision + 1).join("0")
    ;
    money = money.substr(money.length % 3, money.length);
    for (var i = 0, len = money.length; i < len; i++) {
      if (i % 3 === 0) {
        masked += opts.delimiter;
      }
      masked += money[i];
    }
    masked = masked.replace(clearDelimiter, "");
    masked = masked.length ? masked : "0";
    if (!opts.zeroCents) {
      var beginCents = number.length - opts.precision,
          centsValue = number.substr(beginCents, opts.precision),
          centsLength = centsValue.length,
          centsSliced = (opts.precision > centsLength) ? opts.precision : centsLength
      ;
      cents = (cents + centsValue).slice(-centsSliced);
    }
    var output = opts.unit + masked + opts.separator + cents + opts.suffixUnit;
    return output.replace(clearSeparator, "");
  };

  VMasker.toPattern = function(value, opts) {
    var pattern = (typeof opts === 'object' ? opts.pattern : opts),
        patternChars = pattern.replace(/\W/g, ''),
        output = pattern.split(""),
        values = value.toString().replace(/\W/g, ""),
        charsValues = values.replace(/\W/g, ''),
        index = 0,
        i,
        outputLength = output.length,
        placeholder = (typeof opts === 'object' ? opts.placeholder : undefined)
    ;
    
    for (i = 0; i < outputLength; i++) {
      // Reached the end of input
      if (index >= values.length) {
        if (patternChars.length == charsValues.length) {
          return output.join("");
        }
        else if ((placeholder !== undefined) && (patternChars.length > charsValues.length)) {
          return addPlaceholdersToOutput(output, i, placeholder).join("");
        }
        else {
          break;
        }
      }
      // Remaining chars in input
      else{
        if ((output[i] === DIGIT && values[index].match(/[0-9]/)) ||
            (output[i] === ALPHA && values[index].match(/[a-zA-Z]/)) ||
            (output[i] === ALPHANUM && values[index].match(/[0-9a-zA-Z]/))) {
          output[i] = values[index++];
        } else if (output[i] === DIGIT || output[i] === ALPHA || output[i] === ALPHANUM) {
          if(placeholder !== undefined){
            return addPlaceholdersToOutput(output, i, placeholder).join("");
          }
          else{
            return output.slice(0, i).join("");
          }
        }
      }
    }
    return output.join("").substr(0, i);
  };

  VMasker.toNumber = function(value) {
    return value.toString().replace(/(?!^-)[^0-9]/g, "");
  };
  
  VMasker.toAlphaNumeric = function(value) {
    return value.toString().replace(/[^a-z0-9 ]+/i, "");
  };

  return VMasker;
}));