/*
    CRIR - Checkbox & Radio Input Replacement
    Author: Chris Erwin (me[at]chriserwin.com)
    www.chriserwin.com/scripts/crir/

    Updated July 27, 2006.
    Jesse Gavin added the AddEvent function to initialize
    the script. He also converted the script to JSON format.
    
    Updated July 30, 2006.
    Added the ability to tab to elements and use the spacebar
    to check the input element. This bit of functionality was
    based on a tip from Adam Burmister.
*/

crir = {
    init: function() {
        arrLabels = document.getElementsByTagName('label');
    
        searchLabels:
        for (var i=0; i<arrLabels.length; i++) {            
            // get the input element based on the for attribute of the label tag
            if (arrLabels[i].getAttributeNode('for') && arrLabels[i].getAttributeNode('for').value != '') {
                labelElementFor = arrLabels[i].getAttributeNode('for').value;               
                inputElement = document.getElementById(labelElementFor);
            }
            else {              
                continue searchLabels;
            }   
                            
            inputElementClass = inputElement.className; 
        
            // if the input is specified to be hidden intiate it
            if (inputElementClass == 'crirHiddenJS') {
                inputElement.className = 'crirHidden';
                
                inputElementType = inputElement.getAttributeNode('type').value; 
                
                // add the appropriate event listener to the input element
                if (inputElementType == "checkbox") {
                    inputElement.onclick = crir.toggleCheckboxLabel;
                }
                else {
                    inputElement.onclick = crir.toggleRadioLabel;
                }
                
                // set the initial label state
                if (inputElement.checked) {
                    if (inputElementType == 'checkbox') { arrLabels[i].className = 'checkbox_checked'}
                    else { arrLabels[i].className = 'radio_checked' }
                }
                else {
                    if (inputElementType == 'checkbox') { arrLabels[i].className = 'checkbox_unchecked'}
                    else { arrLabels[i].className = 'radio_unchecked' }
                }
            }
            else if (inputElement.nodeName != 'SELECT' && inputElement.getAttributeNode('type').value == 'radio') { // this so even if a radio is not hidden but belongs to a group of hidden radios it will still work.
                arrLabels[i].onclick = crir.toggleRadioLabel;
                inputElement.onclick = crir.toggleRadioLabel;
            }
        }           
    },  
    
    findLabel: function (inputElementID) {
        arrLabels = document.getElementsByTagName('label');
    
        searchLoop:
        for (var i=0; i<arrLabels.length; i++) {
            if (arrLabels[i].getAttributeNode('for') && arrLabels[i].getAttributeNode('for').value == inputElementID) {             
                return arrLabels[i];
                break searchLoop;               
            }
        }       
    },  
    
    toggleCheckboxLabel: function () {
        labelElement = crir.findLabel(this.getAttributeNode('id').value);
    
        if(labelElement.className == 'checkbox_checked') {
            labelElement.className = "checkbox_unchecked";
        }
        else {
            labelElement.className = "checkbox_checked";
        }
    },  
    
    toggleRadioLabel: function () {          
        clickedLabelElement = crir.findLabel(this.getAttributeNode('id').value);
        
        clickedInputElement = this;
        clickedInputElementName = clickedInputElement.getAttributeNode('name').value;
        
        arrInputs = document.getElementsByTagName('input');
    
        // uncheck (label class) all radios in the same group
        for (var i=0; i<arrInputs.length; i++) {            
            inputElementType = arrInputs[i].getAttributeNode('type').value;
            if (inputElementType == 'radio') {
                inputElementName = arrInputs[i].getAttributeNode('name').value;
                inputElementClass = arrInputs[i].className;
                // find radio buttons with the same 'name' as the one we've changed and have a class of chkHidden
                // and then set them to unchecked
                if (inputElementName == clickedInputElementName && inputElementClass == 'crirHidden') {             
                    inputElementID = arrInputs[i].getAttributeNode('id').value;
                    labelElement = crir.findLabel(inputElementID);
                    labelElement.className = 'radio_unchecked';
                }
            }
        }
    
        // if the radio clicked is hidden set the label to checked
        if (clickedInputElement.className == 'crirHidden') {
            clickedLabelElement.className = 'radio_checked';
        }
    },
    
    addEvent: function(element, eventType, doFunction, useCapture){
        if (element.addEventListener) 
        {
            element.addEventListener(eventType, doFunction, useCapture);
            return true;
        } else if (element.attachEvent) {
            var r = element.attachEvent('on' + eventType, doFunction);
            return r;
        } else {
            element['on' + eventType] = doFunction;
        }
    }
}

crir.addEvent(window, 'load', crir.init, false);