/* File Created: 2/27/2011 9:00:13 PM*/
/*
 *
 * Copyright (c) 2006-2010 Sam Collett (http://www.texotela.co.uk)
 * Dual licensed under the MIT (http://www.opensource.org/licenses/mit-license.php)
 * and GPL (http://www.opensource.org/licenses/gpl-license.php) licenses.
 * 
 * Version 1.2
 * Demo: http://www.texotela.co.uk/code/jquery/numeric/
 *
 */
(function($) {
/*
 * Allows only valid characters to be entered into input boxes.
 * Note: does not validate that the final text is a valid number
 * (that could be done by another script, or server-side)
 *
 * @name     numeric
 * @param    decimal      Decimal separator (e.g. '.' or ',' - default is '.'). Pass false for integers
 * @param    callback     A function that runs if the number is not valid (fires onblur)
 * @author   Sam Collett (http://www.texotela.co.uk)
 * @example  $(".numeric").numeric();
 * @example  $(".numeric").numeric(",");
 * @example  $(".numeric").numeric(null, callback);
 *
 */
$.fn.numeric = function(decimal, callback)
{
  decimal = (decimal === false) ? "" : decimal || ".";
  callback = typeof callback == "function" ? callback : function(){};
  return this.data("numeric.decimal", decimal).data("numeric.callback", callback).keypress($.fn.numeric.keypress).blur($.fn.numeric.blur);
}

$.fn.numeric.keypress = function(e)
{
  var decimal = $.data(this, "numeric.decimal");
  var key = e.charCode ? e.charCode : e.keyCode ? e.keyCode : 0;
  // allow enter/return key (only when in an input box)
  if(key == 13 && this.nodeName.toLowerCase() == "input")
  {
    return true;
  }
  else if(key == 13)
  {
    return false;
  }
  var allow = false;
  // allow Ctrl+A
  if((e.ctrlKey && key == 97 /* firefox */) || (e.ctrlKey && key == 65) /* opera */) return true;
  // allow Ctrl+X (cut)
  if((e.ctrlKey && key == 120 /* firefox */) || (e.ctrlKey && key == 88) /* opera */) return true;
  // allow Ctrl+C (copy)
  if((e.ctrlKey && key == 99 /* firefox */) || (e.ctrlKey && key == 67) /* opera */) return true;
  // allow Ctrl+Z (undo)
  if((e.ctrlKey && key == 122 /* firefox */) || (e.ctrlKey && key == 90) /* opera */) return true;
  // allow or deny Ctrl+V (paste), Shift+Ins
  if((e.ctrlKey && key == 118 /* firefox */) || (e.ctrlKey && key == 86) /* opera */
  || (e.shiftKey && key == 45)) return true;
  // if a number was not pressed
  if(key < 48 || key > 57)
  {
    /* '-' only allowed at start */
    if(key == 45 && this.value.length == 0) return true;
    /* only one decimal separator allowed */
    if(decimal && key == decimal.charCodeAt(0) && this.value.indexOf(decimal) != -1)
    {
      allow = false;
    }
    // check for other keys that have special purposes
    if(
      key != 8 /* backspace */ &&
      key != 9 /* tab */ &&
      key != 13 /* enter */ &&
      key != 35 /* end */ &&
      key != 36 /* home */ &&
      key != 37 /* left */ &&
      key != 39 /* right */ &&
      key != 46 /* del */
    )
    {
      allow = false;
    }
    else
    {
      // for detecting special keys (listed above)
      // IE does not support 'charCode' and ignores them in keypress anyway
      if(typeof e.charCode != "undefined")
      {
        // special keys have 'keyCode' and 'which' the same (e.g. backspace)
        if(e.keyCode == e.which && e.which != 0)
        {
          allow = true;
          // . and delete share the same code, don't allow . (will be set to true later if it is the decimal point)
          if(e.which == 46) allow = false;
        }
        // or keyCode != 0 and 'charCode'/'which' = 0
        else if(e.keyCode != 0 && e.charCode == 0 && e.which == 0)
        {
          allow = true;
        }
      }
    }
    // if key pressed is the decimal and it is not already in the field
    if(decimal && key == decimal.charCodeAt(0))
    {
      if(this.value.indexOf(decimal) == -1)
      {
        allow = true;
      }
      else
      {
        allow = false;
      }
    }
  }
  else
  {
    allow = true;
  }
  return allow;
}

$.fn.numeric.blur = function()
{
  var decimal = $.data(this, "numeric.decimal");
  var callback = $.data(this, "numeric.callback");
  var val = $(this).val();
  if(val != "")
  {
    var re = new RegExp("^\\d+$|\\d*" + decimal + "\\d+");
    if(!re.exec(val))
    {
      callback.apply(this);
    }
  }
}

$.fn.removeNumeric = function()
{
  return this.data("numeric.decimal", null).data("numeric.callback", null).unbind("keypress", $.fn.numeric.keypress).unbind("blur", $.fn.numeric.blur);
}

})(jQuery);