/*
  Masked Input plugin for jQuery
  Copyright (c) 2007-2011 Josh Bush (digitalbush.com)
  Licensed under the MIT license (http://digitalbush.com/projects/masked-input-plugin/#license) 
  Version: 1.3
*/
(function($) {
  var pasteEventName = ($.browser.msie ? 'paste' : 'input') + ".mask";
  var iPhone = (window.orientation != undefined);

  $.mask = {
    //Predefined character definitions
    definitions: {
      '9': "[0-9]",
      'a': "[A-Za-z]",
      '*': "[A-Za-z0-9]"
    },
    dataName:"rawMaskFn"
  };

  $.fn.extend({
    //Helper Function for Caret positioning
    caret: function(begin, end) {
      if (this.length == 0) return;
      if (typeof begin == 'number') {
        end = (typeof end == 'number') ? end : begin;
        return this.each(function() {
          if (this.setSelectionRange) {
            this.setSelectionRange(begin, end);
          } else if (this.createTextRange) {
            var range = this.createTextRange();
            range.collapse(true);
            range.moveEnd('character', end);
            range.moveStart('character', begin);
            range.select();
          }
        });
      } else {
        if (this[0].setSelectionRange) {
          begin = this[0].selectionStart;
          end = this[0].selectionEnd;
        } else if (document.selection && document.selection.createRange) {
          var range = document.selection.createRange();
          begin = 0 - range.duplicate().moveStart('character', -100000);
          end = begin + range.text.length;
        }
        return { begin: begin, end: end };
      }
    },
    unmask: function() { return this.trigger("unmask"); },
    mask: function(mask, settings) {
      if (!mask && this.length > 0) {
        var input = $(this[0]);
        return input.data($.mask.dataName)();
      }
      settings = $.extend({
        placeholder: "_",
        completed: null
      }, settings);

      var defs = $.mask.definitions;
      var tests = [];
      var partialPosition = mask.length;
      var firstNonMaskPos = null;
      var len = mask.length;

      $.each(mask.split(""), function(i, c) {
        if (c == '?') {
          len--;
          partialPosition = i;
        } else if (defs[c]) {
          tests.push(new RegExp(defs[c]));
          if(firstNonMaskPos==null)
            firstNonMaskPos =  tests.length - 1;
        } else {
          tests.push(null);
        }
      });

      return this.trigger("unmask").each(function() {
        var input = $(this);
        var buffer = $.map(mask.split(""), function(c, i) { if (c != '?') return defs[c] ? settings.placeholder : c });
        var focusText = input.val();

        function seekNext(pos) {
          while (++pos <= len && !tests[pos]);
          return pos;
        };
        function seekPrev(pos) {
          while (--pos >= 0 && !tests[pos]);
          return pos;
        };

        function shiftL(begin,end) {
          if(begin<0)
             return;
          for (var i = begin,j = seekNext(end); i < len; i++) {
            if (tests[i]) {
              if (j < len && tests[i].test(buffer[j])) {
                buffer[i] = buffer[j];
                buffer[j] = settings.placeholder;
              } else
                break;
              j = seekNext(j);
            }
          }
          writeBuffer();
          input.caret(Math.max(firstNonMaskPos, begin));
        };

        function shiftR(pos) {
          for (var i = pos, c = settings.placeholder; i < len; i++) {
            if (tests[i]) {
              var j = seekNext(i);
              var t = buffer[i];
              buffer[i] = c;
              if (j < len && tests[j].test(t))
                c = t;
              else
                break;
            }
          }
        };

        function keydownEvent(e) {
          var k=e.which;

          //backspace, delete, and escape get special treatment
          if(k == 8 || k == 46 || (iPhone && k == 127)){
            var pos = input.caret(),
              begin = pos.begin,
              end = pos.end;
            
            if(end-begin==0){
              begin=k!=46?seekPrev(begin):(end=seekNext(begin-1));
              end=k==46?seekNext(end):end;
            }
            clearBuffer(begin, end);
            shiftL(begin,end-1);

            return false;
          } else if (k == 27) {//escape
            input.val(focusText);
            input.caret(0, checkVal());
            return false;
          }
        };

        function keypressEvent(e) {
          var k = e.which,
            pos = input.caret();
          if (e.ctrlKey || e.altKey || e.metaKey || k<32) {//Ignore
            return true;
          } else if (k) {
            if(pos.end-pos.begin!=0){
              clearBuffer(pos.begin, pos.end);
              shiftL(pos.begin, pos.end-1);
            }

            var p = seekNext(pos.begin - 1);
            if (p < len) {
              var c = String.fromCharCode(k);
              if (tests[p].test(c)) {
                shiftR(p);
                buffer[p] = c;
                writeBuffer();
                var next = seekNext(p);
                input.caret(next);
                if (settings.completed && next >= len)
                  settings.completed.call(input);
              }
            }
            return false;
          }
        };

        function clearBuffer(start, end) {
          for (var i = start; i < end && i < len; i++) {
            if (tests[i])
              buffer[i] = settings.placeholder;
          }
        };

        function writeBuffer() { return input.val(buffer.join('')).val(); };

        function checkVal(allow) {
          //try to place characters where they belong
          var test = input.val();
          var lastMatch = -1;
          for (var i = 0, pos = 0; i < len; i++) {
            if (tests[i]) {
              buffer[i] = settings.placeholder;
              while (pos++ < test.length) {
                var c = test.charAt(pos - 1);
                if (tests[i].test(c)) {
                  buffer[i] = c;
                  lastMatch = i;
                  break;
                }
              }
              if (pos > test.length)
                break;
            } else if (buffer[i] == test.charAt(pos) && i!=partialPosition) {
              pos++;
              lastMatch = i;
            }
          }
          if (!allow && lastMatch + 1 < partialPosition) {
            input.val("");
            clearBuffer(0, len);
          } else if (allow || lastMatch + 1 >= partialPosition) {
            writeBuffer();
            if (!allow) input.val(input.val().substring(0, lastMatch + 1));
          }
          return (partialPosition ? i : firstNonMaskPos);
        };

        input.data($.mask.dataName,function(){
          return $.map(buffer, function(c, i) {
            return tests[i]&&c!=settings.placeholder ? c : null;
          }).join('');
        })

        if (!input.attr("readonly"))
          input
          .one("unmask", function() {
            input
              .unbind(".mask")
              .removeData($.mask.dataName);
          })
          .bind("focus.mask", function() {
            focusText = input.val();
            var pos = checkVal();
            writeBuffer();
            var moveCaret=function(){
              if (pos == mask.length)
                input.caret(0, pos);
              else
                input.caret(pos);
            };
            ($.browser.msie ? moveCaret:function(){setTimeout(moveCaret,0)})();
          })
          .bind("blur.mask", function() {
            checkVal();
            if (input.val() != focusText)
              input.change();
          })
          .bind("keydown.mask", keydownEvent)
          .bind("keypress.mask", keypressEvent)
          .bind(pasteEventName, function() {
            setTimeout(function() { input.caret(checkVal(true)); }, 0);
          });

        checkVal(); //Perform initial check for existing values
      });
    }
  });
})(jQuery);