// Get object by its name or id
function GetObject( obj_name )
{
    var obj = null;

	if( document.all )
	{
    	obj = document.all(obj_name);
    }
    else if (document.getElementById)
    {
    	obj = document.getElementById(obj_name);
    }
    else if(document.layers)
    {
    	obj = document.layers[obj_name];
    }
    else
    {
    	obj = null;
    }

    return obj;
}

// Check if values selected in drop down menus are valid
function CheckDatesItem( day_name, month_name )
{
	var day_obj, month_obj;
	var monthMax = new Array(31, 29, 31, 30, 31, 30, 31, 31 ,30, 31, 30, 31);

	day_obj = GetObject( day_name );
	month_obj = GetObject( month_name );

    if( day_obj && month_obj )
    {
		var sel_year = month_obj.options[month_obj.selectedIndex].value.substring(0, 4);
		var sel_month = month_obj.options[month_obj.selectedIndex].value.substring(4, 6);
		var sel_day = day_obj.options[day_obj.selectedIndex].value;

		var month = parseInt( sel_month, 10 );
		var day = parseInt( sel_day, 10 );
		var year = parseInt( sel_year, 10 );

		if (day > monthMax[month-1])
		{
			return false;
		}

        /*
		// Now check if the date is in future but not in past
		var now_date = new Date();
		var sel_date = new Date(year, month-1, day, now_date.getHours(), now_date.getMonth(), now_date.getSeconds());

		if( now_date.getTime() > sel_date.getTime() )
		{
			return false;
		}
		*/
    }

    return true;
}

// Check if values entered in text boxes for time are valid
function CheckTimesItem( hour_name, min_name )
{
	var hour_obj, min_obj;

	if( document.all )
	{
    	hour_obj = document.all(hour_name);
    	min_obj = document.all(min_name);
    }
    else if (document.getElementById)
    {
    	hour_obj = document.getElementById(hour_name);
    	min_obj = document.getElementById(min_name);
    }
    else if(document.layers)
    {
    	hour_obj = document.layers[hour_name];
    	min_obj = document.layers[min_name];
    }

    if( hour_obj && min_obj )
    {
		var hour = parseInt( hour_obj.value, 10 );
		var min = parseInt( min_obj.value, 10 );

		if( isNaN(hour) || isNaN(min) )
		{
        	return false;
        }

		if ( (hour < 0 ) || (hour > 23) )
		{
			return false;
		}

        if ( (min < 0 ) || (min > 59) )
		{
			return false;
		}
    }

    return true;
}