/**
 * Numeric Stepper
 * ------------------------------------------------
 *
 * Copyright 2007 Ca Phun Ung
 *	
 * This software is licensed under the CC-GNU LGPL
 * http://creativecommons.org/licenses/LGPL/2.1/
 * 
 * Version 0.1
 *
 */

/**
 * Numeric Stepper Class.
 */
var NumericStepper = {	
    sLimits: {},
    register : function(name, minValue, maxValue, stepSize){
        NumericStepper.sLimits[name] = {
            minValue: minValue,
            maxValue: maxValue
        };
        //console.debug(NumericStepper.sLimits);
        this.minValue = minValue;
        this.maxValue = maxValue;
        this.stepSize = stepSize;
        var elements = getElementsByClassName(document, "*", name);
        for (var i=0; i<elements.length; i++){
            var textbox = elements[i].getElementsByTagName('input')[0];
            if (textbox){
                if (textbox.value == undefined || textbox.value == '' || isNaN(textbox.value))
                    textbox.value = 0;
                textbox.onkeypress = function(e){
                    if(window.event){
                        keynum = e.keyCode; // IE
                    } else if(e.which){
                        keynum = e.which; // Netscape/Firefox/Opera
                    }
                    keychar = String.fromCharCode(keynum);
                    numcheck = /[0-9\-]/;
                    if (keynum==8)
                        return true;
                    else
                        return numcheck.test(keychar);
                };
                textbox.onblur = function(){
                    
                    var boxClassName = this.parentNode.className;
                    
                    if (parseInt(this.value) < NumericStepper.sLimits[boxClassName].minValue){
                        this.value = NumericStepper.sLimits[boxClassName].minValue;
                    }
                        
                    if (parseInt(this.value) >NumericStepper.sLimits[boxClassName]. maxValue){
                        this.value = NumericStepper.sLimits[boxClassName].maxValue;
                    }
                        
                };
                var buttons = elements[i].getElementsByTagName('button');
                if (buttons[0]){
                    this.addButtonEvent(buttons[0], textbox, this.stepUp);
                }
                if (buttons[1])
                    this.addButtonEvent(buttons[1], textbox, this.stepDown);
            }
        }
    }
    ,
    addButtonEvent:function(o,textbox, func){
        o.textbox = textbox;
        // convert button type to button to prevent form submission onclick
        if (o.getAttribute("type")=="submit"){
            o.removeAttribute("type"); // IE fix
            o.setAttribute("type","button");
        }
        o.onclick = func;
    }
    ,
    stepUp:function(){
        NumericStepper.stepper(this.textbox, NumericStepper.stepSize);
    }
    ,
    stepDown:function(){
        NumericStepper.stepper(this.textbox, -NumericStepper.stepSize);
    }
    ,
    stepper:function(textbox, val){
        if (textbox == undefined)
            return false;
        var boxClassName = textbox.parentNode.className;
        
        if (val == undefined || isNaN(val))
            val = 1;
        if (textbox.value == undefined || textbox.value == '' || isNaN(textbox.value))
            textbox.value = 0;
        textbox.value = parseInt(textbox.value) + parseInt(val);
        if (parseInt(textbox.value) < NumericStepper.sLimits[boxClassName].minValue)
            textbox.value = NumericStepper.sLimits[boxClassName].minValue;
        if (parseInt(textbox.value) >NumericStepper.sLimits[boxClassName]. maxValue)
            textbox.value = NumericStepper.sLimits[boxClassName].maxValue;
    }
}

/**
  getElementsByClassName - returns an array of elements selected by their class name.
  @author Jonathan Snook <http://www.snook.ca/jonathan>
  @add-ons Robert Nyman <http://www.robertnyman.com>
*/
function getElementsByClassName(oElm, strTagName, strClassName){
    var arrElements = (strTagName == "*" && oElm.all)? oElm.all : oElm.getElementsByTagName(strTagName);
    var arrReturnElements = new Array();
    strClassName = strClassName.replace(/-/g, "\-");
    var oRegExp = new RegExp("(^|\s)" + strClassName + "(\s|$)");
    var oElement;
    for(var i=0; i<arrElements.length; i++){
        oElement = arrElements[i];
        if(oRegExp.test(oElement.className)){
            arrReturnElements.push(oElement);
        }
    }
    return (arrReturnElements)
}

function initNumericStepper(){
    var cTypeStepper = NumericStepper.register("numeric-stepper-ctype", 1, 18, 1);
    var myNumericStepper = NumericStepper.register("numeric-stepper", 1, 10000, 1);
        
}

/**
 * addEvent - simple window.onload event loader.
 */
function addEvent(o, evt, f){
    var r = false;
    if (o.addEventListener){
        o.addEventListener(evt, f, false);
        r = true;
    }
    else if (o.attachEvent)
        r = o.attachEvent("on"+evt, f);
    return r;
}
addEvent(window, "load", initNumericStepper);