function showDiv(id) {
  document.getElementById(id).style.display='block';
}

function hideDiv(id) {
  document.getElementById(id).style.display='none';
}

function returnMsg(msg) {
  alert(msg);
  return false;
}

function enterInput(id,val) {
	if (document.getElementById(id).value==val) {
		document.getElementById(id).value='';
	}
}

function leaveInput(id,val) {
	if (document.getElementById(id).value=='') {
		document.getElementById(id).value=val;
	}
}

function account_type(type) {
 if(type=='retail') {
    Effect.Fade('wholesale');
    document.getElementById('cname').value='';
    document.getElementById('nip').value='';
  } else if(type=='wholesale' || type=='shop') {
    Effect.Appear('wholesale');
  }
}

function checkSizeSelection(num,msg) {
  selected=false;
  for(i=1;i<=num;i++) {
    if(document.getElementById('size'+i).checked==true) selected=true;
  }
  if(selected==false) alert(msg);
  return selected;
}

function checkAmount(msg) {
  amount=document.getElementById('amount').value;
  if(amount=='' || isNaN(parseFloat(amount))) {
    alert(msg);
    return false;
  } else {
    return true;
  }
}

function checkAskForm(msg_email,msg_content) {
  check=true;
  mail=document.getElementById('email').value;
	filter=/^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
	if(filter.test(mail)) {
		check=true;
		if(document.getElementById('question').value=='') {
		  alert(msg_content);
      check=false;
    }
	} else if(!filter.test(mail)) {
    alert(msg_email);
		check=false;
	}
  return check;
}

function updateAddress(field,value) {
  document.getElementById(field).innerHTML=value;
}