function t_sub_opts(){
	if( document.getElementById('member').checked ){
		document.getElementById('subscription').style.display = 'none';
		document.getElementById('payment').style.display = 'none';
		document.getElementById('join-now').style.display = 'none';
		document.getElementById('billing-options').style.display = 'none';
		document.getElementById('credit-card').style.display = 'none';
		document.getElementById('billing').style.display = 'none';
	} else {
		document.getElementById('subscription').style.display = 'block';
		document.getElementById('payment').style.display = 'block';
	}
}

function t_join_now(){
	if( document.getElementById('join').checked ){
		document.getElementById('join-now').style.display = 'block';
		document.getElementById('zoo-bill').style.display = 'block';
		document.getElementById('payment').style.display = 'block';
		t_billing();
	} else {
		document.getElementById('join-now').style.display = 'none';
		document.getElementById('zoo-bill').style.display = 'none';
		
		if( document.getElementById('single').checked ){
			document.getElementById('payment').style.display = 'none';
			document.getElementById('billing-options').style.display = 'none';
			document.getElementById('billing').style.display = 'none';
			document.getElementById('credit-card').style.display = 'none';
		} else {
			document.getElementById('payment').style.display = 'block';
			t_billing();
		}
	}
	
}

function t_billing(){
	if( document.getElementById('cc').checked ){
		document.getElementById('billing-options').style.display = 'block';
		document.getElementById('bill-instructions').style.display = 'block';
		document.getElementById('credit-card').style.display = 'block';
		t_billing_address();
	} else {
		document.getElementById('billing-options').style.display = 'none';
		document.getElementById('bill-instructions').style.display = 'none';
		document.getElementById('billing').style.display = 'none';
		document.getElementById('credit-card').style.display = 'none';
		
	}
}

function t_billing_address(){
	if( document.getElementById('different').checked ){
		document.getElementById('billing').style.display = 'block';
	} else {
		document.getElementById('billing').style.display = 'none';
	}
}

function init(){

	/*======================================== set default toggle states */
	//------------------------------------------------ subscription options
	if( !document.getElementById('non-member').checked ){
		document.getElementById('subscription').style.display = 'none';
		document.getElementById('payment').style.display = 'none';
	}
	addEvent(document.getElementById('member'), 'click', t_sub_opts);
	addEvent(document.getElementById('non-member'), 'click', t_sub_opts);
	//------------------------------------------------------------ join now
	if( !document.getElementById('join').checked ){
		document.getElementById('join-now').style.display = 'none';
		document.getElementById('zoo-bill').style.display = 'none';
	}
	addEvent(document.getElementById('join'), 'click', t_join_now);
	addEvent(document.getElementById('year'), 'click', t_join_now);
	addEvent(document.getElementById('half-year'), 'click', t_join_now);
	addEvent(document.getElementById('single'), 'click', t_join_now);
	//----------------------------------------------------- payment options
	if( !document.getElementById('paypal').checked && !document.getElementById('cc').checked ){
		document.getElementById('billing-options').style.display = 'none';
	}
	if( !document.getElementById('different').checked ){
		document.getElementById('billing').style.display = 'none';
	}
	if( !document.getElementById('cc').checked ){
		document.getElementById('credit-card').style.display = 'none';
	document.getElementById('bill-instructions').style.display = 'none';
	}
	
	addEvent(document.getElementById('paypal'), 'click', t_billing);
	addEvent(document.getElementById('cc'), 'click', t_billing);
	
	addEvent(document.getElementById('as-account'), 'click', t_billing_address);
	addEvent(document.getElementById('as-zoo'), 'click', t_billing_address);
	addEvent(document.getElementById('different'), 'click', t_billing_address);
	
}

addEvent(window,'unload',EventCache.flush);
addEvent(window,'load', init);