/*
 *
 * 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 (jQuery) {
    /*
    * 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  jQuery(".numeric").numeric();
    * @example  jQuery(".numeric").numeric(",");
    * @example  jQuery(".numeric").numeric(null, callback);
    *
    */


    jQuery.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(jQuery.fn.numeric.keypress).blur(jQuery.fn.numeric.blur);
    }

    jQuery.fn.numeric.keypress = function (e) {
        var decimal = jQuery.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;
    }

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

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

})(jQuery);