/**
* submit search form
*/
function doSubmit()
{
	$('form1').__VIEWSTATE.name="name";
    
    //validate required field
    if($F("search_from") == "" || $F("search_to") == "")
    {
        alert("invalid departure or return city");
        return;
    }
    else if($F("search_departure") == "")
    {
        alert("departure date is required");
        return;    
    }
    else if($F("search_roundtrip") == "1" && $F("search_return") == "")
    {
        alert("return date is required");
        return;
    }
    
    //checking selling fare table before submit
	var url = "services/availfare.aspx?from=" + $F("search_from") +"&to=" + $F("search_to") + "&departure="+$F("search_departure");
	
	if($F("search_roundtrip") == "1")
	{ //return trip must present return date
	    url += "&roundtrip=" + $F("search_roundtrip")
	    url += "&return=" + $F("search_return");
	}
	else
	{
	    url += "&roundtrip=0";
	}
	url += "&" + new Date();
	//alert(url);
	//return;
	new Ajax.Request(url, {
          method: 'get',
          onSuccess: function(transport) {
            if(transport.responseText == "0")
            {
                $('form1').submit();
            }
            else
            {   //display  error detail
                alert(transport.responseText);             
            }
          }
        });
}