Boxchecked validation

<script language="javascript" type="text/javascript">
 
function submitbutton(pressbutton)
{
	var form = document.adminForm;
		if (pressbutton == 'edit')
			{
			if(form.boxchecked.value == 0){
				alert("<?php echo JText::_( 'PLEASE SELECT A PAGE TO EDIT', true ); ?>");
				} else {
				if(form.boxchecked.value > 1){
					alert("<?php echo JText::_( 'YOU COULD EDIT ONLY ONE PAGE AT A TIME', true ); ?>");
					} else {
					submitform( pressbutton );
					return;
					}
				}
			} 	
		if (pressbutton == 'delete')
			{
			if(form.boxchecked.value==0){
				alert("<?php echo JText::_( 'PLEASE SELECT A PAGE TO DELETE', true ); ?>");
				} else {
				if(form.boxchecked.value > 1){
					if ( confirm("<?php echo JText::_( 'ARE YOU SURE YOU WANT TO DELETE THESE ITEMS?' ); ?>") )
						{
						submitform( pressbutton );
						return;
						} else {
						return;
						}
 
					} else {
					if ( confirm("<?php echo JText::_( 'ARE YOU SURE YOU WANT TO DELETE THIS ITEM?' ); ?>") )
						{
						submitform( pressbutton );
						return;
						} else {
						return;
						}
					}
				}
			}
		if (pressbutton == 'new'){
			if(form.boxchecked.value > 0){
				alert("<?php echo JText::_( 'YOU COULD NOT HAVE A PAGE SELECTED TO CREATE ONE', true ); ?>");
				} else {
				submitform( pressbutton );
				return;
				}
			}
 
}
</script>