function DepSelectOne(masterSelect){
	var frm = masterSelect.form;
	this.selectedBlock = 0;
	this.selBoxes = new Array(masterSelect);
	if((frm)&&(typeof Option != 'undefined')){
		for(var c = 1;c < arguments.length;c++){
			var selObj = frm[arguments[c]];
			if((selObj)&&(selObj.type.indexOf('select') == 0)&&(selObj.type.indexOf('mult') < 0)&&(selObj.options.length > 2)){
				this.selBoxes[this.selBoxes.length] = frm[arguments[c]];
			}
		}
		if((this.selBoxes.length >1)&&(this.selBoxes.length == arguments.length)){
			this.selectElement = this.selBoxes[0];
			DepSelectOne.inst[this.index = this.selectElement.name] = this;	//keep global record of this object instance.
			this.selBoxes[0] = this;
			this.optionBlock = new OptionBlock(0, this.selectElement, this.selectElement.options[0].value, this, 0);
			this.next = new DepSelectOneNext(this.selBoxes, 1);
			this.next.setSelection(this.optionBlock.getSelection());
			this.selectElement.onchange = new Function('DepSelectOne.inst[\''+this.index+'\'].handleChange(0)');
		}else{
			//alert('DepSelectOne constructor could not find\nsufficient properly configured SELECT elements\nto initialise.');
		}
	}
}
DepSelectOne.inst = {};	//Globally accessible object to hold instances of the DepSelectOne Class.
//call chain terminating functions.
DepSelectOne.prototype.validateNext = DepSelectOne.prototype.reset = DepSelectOne.prototype.setSelection = DepSelectOne.prototype.setSelectedFromChild = function(){return true;}
DepSelectOne.prototype.validate = function(){
	return ((this.optionBlock.lastSelection < 0)?false:this.next.validateNext());
}
DepSelectOne.prototype.init = function(selectedBlock){
	if(selectedBlock >= 0){
		this.optionBlock.lastSelection = selectedBlock;
	}
	if(this.optionBlock.lastSelection >= 0){
		this.optionBlock.doElement();
		if(window.setTimeout)setTimeout('DepSelectOne.inst[\''+this.index+'\'].refresh();', 5); //fix for Opera 7 timing problem. Harmless otherwise.
	}
}
DepSelectOne.prototype.handleChange = function(ind){
	this.selBoxes[ind].changed();
	if(window.setTimeout)setTimeout('DepSelectOne.inst[\''+this.index+'\'].refresh();', 5); //fix for Opera 7 timing problem. Harmless otherwise.
}
DepSelectOne.prototype.refresh = function(){
	this.selectElement.selectedIndex = this.optionBlock.lastSelection;
	this.next.reset();
}
DepSelectOne.prototype.changed = function(){
	this.optionBlock.readState();
	this.next.setSelection(this.optionBlock.getSelection());
}

function DepSelectOneNext(selBoxes, selBoxIndex){
	this.selectedBlock = -1;
	this.classObj = selBoxes[0];
	this.previous = selBoxes[(selBoxIndex-1)]
	this.selectElement = selBoxes[selBoxIndex];
	selBoxes[selBoxIndex] = this;
	this.selectElement.onchange = new Function('DepSelectOne.inst[\''+this.classObj.index+'\'].handleChange('+selBoxIndex+')');
	this.seperatorOption = new DepOption(this.selectElement.options[0]);
	this.optionBlocks = [];
	var startIndex = 1;
	while(startIndex < this.selectElement.options.length){
		var nextIndex = this.optionBlocks.length;
		this.optionBlocks[nextIndex] = new OptionBlock(startIndex, this.selectElement, this.selectElement.options[0].value, this, nextIndex);
		startIndex += this.optionBlocks[nextIndex].getOptionsTotal();
	}
	for(var cnt = 0,c = 0;c < this.optionBlocks.length;c++){
		this.optionBlocks[c].blockStart = cnt;
		cnt += this.optionBlocks[c].getItems();
	}
	if(++selBoxIndex < selBoxes.length){
		this.next = new DepSelectOneNext(selBoxes, selBoxIndex);
	}else{
		this.next = this.classObj;
		this.previous.init(this.selectedBlock);
	}
}
DepSelectOneNext.prototype.reset = function(){
	if((this.selectedBlock >= 0)&&(this.optionBlocks[this.selectedBlock].lastSelection >= 0)){
		this.selectElement.selectedIndex = this.optionBlocks[this.selectedBlock].lastSelection;
		this.next.reset();
	}
}
DepSelectOneNext.prototype.setSelection = function(selBlock){
	this.selectedBlock = selBlock;
	if(this.selectedBlock < 0){
		var opt = this.selectElement.options;
		opt.length = 0; //clear options
		opt[0] = this.seperatorOption.getOption();
		this.selectElement.selectedIndex = 0;
		this.next.setSelection(-1);
	}else{
		var blk = this.optionBlocks[this.selectedBlock];
		blk.doElement();
		this.next.setSelection(blk.getSelection());
	}
}
DepSelectOneNext.prototype.changed = function(){
	if(this.selectedBlock >= 0){
		var blk = this.optionBlocks[this.selectedBlock];
		blk.readState();
		this.next.setSelection(blk.getSelection());
	}
}
DepSelectOneNext.prototype.setSelectedFromChild = function(blockIndex){
	if(this.selectedBlock < 0){	//only set from OptonBlock on the first attempt.
		this.selectedBlock = blockIndex;
	}
}
DepSelectOneNext.prototype.init = function(selBlock){
	if(selBlock >= 0){
		var blockIndex = 0;
		while(!this.optionBlocks[blockIndex++].nextBlockTest(selBlock));
	}
	this.previous.init(this.selectedBlock);
}
DepSelectOneNext.prototype.validateNext = function(){
	return (((this.selectedBlock < 0)||(this.optionBlocks[this.selectedBlock].lastSelection < 0))?false:this.next.validateNext());
}

function DepOption(optEl){
	this.value = optEl.value;
	this.text = optEl.text;
}
DepOption.prototype.getOption = function(){
	return new Option(this.text, this.value);
}

function OptionBlock(startIndex, selectElement, seperatorValue, owner, blockIndex){
	this.blockStart = 0;
	this.owner = owner;
	this.index = blockIndex;
	this.selectElement = selectElement;
	this.seperators = [];
	this.optionBlock = [];
	this.lastSelection = -1;
	var opts = this.selectElement.options;
	while((startIndex < opts.length)&&(opts[startIndex].value == seperatorValue)){
		this.seperators[this.seperators.length] = new DepOption(opts[startIndex++]);
	}
	while((startIndex < opts.length)&&(opts[startIndex].value != seperatorValue)){
		if((this.lastSelection < 0)&&(opts[startIndex].selected == true)){
			this.lastSelection = this.optionBlock.length; //record first item selected, if any.
		}
		this.optionBlock[this.optionBlock.length] = new DepOption(opts[startIndex++]);
	}
	if(this.lastSelection >= 0)this.owner.setSelectedFromChild(this.index)
}
OptionBlock.prototype.getOptionsTotal = function(){
	return (this.seperators.length + this.optionBlock.length);
}
OptionBlock.prototype.getItems = function(){
	return this.optionBlock.length;
}
OptionBlock.prototype.nextBlockTest = function(selBlock){
	if((selBlock >= this.blockStart)&&(selBlock < this.blockStart+this.optionBlock.length)){
		this.lastSelection = selBlock - this.blockStart;
		this.owner.selectedBlock = this.index;
		return true;
	}
	return false;
}
OptionBlock.prototype.getSelection = function(){
	return ((this.lastSelection < 0)?-1:(this.blockStart+this.lastSelection));
}
OptionBlock.prototype.doElement = function(){
	var opt = this.selectElement.options;
	opt.length = 0; //clear options
	if((this.lastSelection < 0)&&(this.seperators.length > 0)){
		opt[opt.length] = this.seperators[(this.seperators.length-1)].getOption();
	}
	for(var c = 0;c < this.optionBlock.length;c++){
		opt[opt.length] = this.optionBlock[c].getOption();
	}
	this.selectElement.selectedIndex = ((this.lastSelection < 0)?0:this.lastSelection);
}
OptionBlock.prototype.readState = function(){
	if(this.lastSelection < 0){
		this.lastSelection = (this.selectElement.selectedIndex - 1);
		this.doElement();
	}else{
		this.lastSelection = this.selectElement.selectedIndex;
	}
}


/*
demonstration use of validate function of DepSelectOne Class
*/
function testSel(){
	if( DepSelectOne.inst['iid'].validate() ){ 
		document.registration.submit();
	}else{
		alert('Va rugam selectati categoria subcategoria si subsubcategoria.');
	}
}