var stringMaker;
var xmlDoc;
var rootNode;
var whrNode;
function CheckValues(nlat_str,slat_str,wlon_str,elon_str){
	nlat_str=nlat_str.replace(/^\s+|\s+$/g,'');
	slat_str=slat_str.replace(/^\s+|\s+$/g,'');
	wlon_str=wlon_str.replace(/^\s+|\s+$/g,'');
	elon_str=elon_str.replace(/^\s+|\s+$/g,'');

	/********Check if all values are blank or all are valid********/
	if(nlat_str == "" && slat_str == "" && elon_str == "" && wlon_str == ""){
		return "Blank";
	}
	else{
		if(nlat_str==""){
			return "Please enter a North latitude ";
		}
		if(slat_str==""){
			return "Please enter a South latitude ";
		}
		if(wlon_str==""){
			return "Please enter a West Longitude ";
		}
		if(elon_str==""){
			return "Please enter an East Longitude ";
		}
	}
  	/******** Check all latitudes and longitudes are numbers ***********/	
	if(((/^[-+]?[0-9]+(\.[0-9]+)?$/.test(nlat_str))==0) && nlat_str!="")
	{
		return "North Latitude is not a number ";
	}
	if((/^[-+]?[0-9]+(\.[0-9]+)?$/.test(slat_str))==0 && slat_str!="")
	{
		return "South Latitude is not a number ";
	}
	if((/^[-+]?[0-9]+(\.[0-9]+)?$/.test(wlon_str))==0 && wlon_str!="")
	{
		return "West longitude is not a number ";
	}
	if((/^[-+]?[0-9]+(\.[0-9]+)?$/.test(elon_str))==0 && elon_str!="")
	{
		return "East longitude is not a number ";
	}


	slat = parseFloat(slat_str);
	nlat = parseFloat(nlat_str);
	elon = parseFloat(elon_str);
	wlon = parseFloat(wlon_str);
	
	/*if(nlat_str == ""){ 
		nlat=0;
	}
	if(slat_str == ""){ 
		slat=0;
	}
	if(wlon_str == ""){ 
		wlon=0;
	}
	if(elon_str == ""){ 
		elon=0;
	}*/
  	/******** Check North latitude is between -90 and 90 ***********/	
	if(nlat<-90){
		return "North Latitude is less than -90 ";
	}
	if(nlat>90){
		return "North Latitude is greater than 90 ";
	}

  	/******** Check South latitude is between -90 and 90 ***********/	
	if(slat<-90){
		return "South Latitude is less than -90 ";
	}
	if(slat>90){
		return "South Latitude is greater than 90 ";
	}

  	/******** Check West longitude is between -180 and 180 ***********/	
	if(wlon<-180){
		return "West Longitude is less than -180";
	}	
	if(wlon>180){
		return "West Longitude is greater than 180";
	}

  	/******** Check East longitude is between -180 and 180 ***********/	
	if(elon<-180){
		return "East Longitude is less than -180";
	}
	if(elon>180){
		return "East Longitude is greater than 180";
	}


  	/******** Check North latitude is greater than South latitude ***********/	
	if(nlat<slat){
		return "North latitude is less than South latitude";
	}
	if(nlat==slat){
		return "North latitude must be greater than South latitude";
	}

  	/******** Check East longitude is greater than West longitude ***********/	
	if(elon<wlon){
		return "East longitude is less than West longitude";
	}
	if(elon==wlon){
		return "East longitude must be greater than West longitude";
	}

        return "Correct"; 
}
function CheckParams(){
	var slat=document.getElementsByName("south_latitude");
	var nlat=document.getElementsByName("north_latitude");
	var elon=document.getElementsByName("east_longitude");
	var wlon=document.getElementsByName("west_longitude");
	var text=document.getElementsByName("bounding_coordinates");
	var correct_data=0;
	retstr = CheckValues(nlat[0].value,slat[0].value,wlon[0].value,elon[0].value);
	if(retstr=="Correct"){
		//If correct values are passed in Option 1 then make sure the user hasnt entered anything in Option 2
		if(text[0].value!="" ){
			alert("Please complete subsetting Option 1 or 2 but not both");
			return;
		}
		else
			correct_data=1;
	}
	else if(retstr=="Blank"){
		//If Option 1 is left blank then test the option 2 values
		var lines=text[0].value.split("\n");
		for(i=0;i<lines.length;i++){
			if(lines[i].match(/\w+/)){	
				var words=lines[i].split(",");
				//slat=words[0].replace(/^\s*|\s*$/g,"");
				slat=words[0];
				nlat=words[2];
				wlon=words[1];
				elon=words[3];
				retstr = CheckValues(nlat,slat,wlon,elon);
				if(retstr!="Correct"){
					linenum = i+1;
					alert(retstr + " for line " + linenum + " in Option 2");	
					return;	
				}
				else{
					correct_data=1;
				}
			}
		}//end for
	}
	else{//Incorrect values are passed for option 1
		alert(retstr + " for Option 1");	
		return;	
	}
	if(correct_data==1)
		/******** alert("Correct values passed"); ********/
                /******** return; ********/
               document.form.submit(); 
	else
		alert("Please complete subsetting Option 1 or 2");	
	//Do rest of processing here
}