function enableOptions()
{
	document.getElementById("disabledOptions").style.display = 'none';
	document.getElementById("enabledOptions").style.display = 'block';
}

function disableOptions()
{
	document.getElementById("disabledOptions").style.display = 'block';
	document.getElementById("enabledOptions").style.display = 'none';
}

function checkSelectionCount(tariff)
{
	var checked = 0;
	var checkboxes = document.getElementsByName('compare[]');
	
	for (i = 0; i < checkboxes.length; i++)
	{
		if(checkboxes[i].type == 'checkbox')
		{
			if(checkboxes[i].checked == true)
			{
				checked++;
			}
		}
	}
	
	if(checked > 2)
	{
		alert("Sie können nur 2 Tarife miteinander vergleichen");
		
		checkboxes[tariff].checked = false;
		checked = checked - 1;
	}
	
	document.getElementById('selectionCountTop').innerHTML = checked;
}

function compareTariffs()
{
	var checked = 0;
	var t1 = null;
	var t2 = null;
	var checkboxes = document.getElementsByName('compare[]');
	
	for (i = 0; i < checkboxes.length; i++)
	{
		if(checkboxes[i].type == 'checkbox')
		{
			if(checkboxes[i].checked == true)
			{
				checked++;
				
				if(t1 == null)
				{
					t1 = checkboxes[i].value;
				}
				else
				{
					t2 = checkboxes[i].value;
				}
			}
		}
	}
	
	if(checked < 2)
	{
		alert("Bitte wählen Sie 2 Tarife aus der Liste aus.");
	}
	else
	{
		window.location.href = './stromvergleich.php' + window.location.search + '&t1=' + t1 + '&t2=' + t2;
	}
}