// LAYERS parameter: config_a_b_c
//    a = 1 for depth in meters, 2 for depth in feet, 3 for fathoms
//    b = 10.00: for 10.00 m safety depth (beginning of blue coloring) (unit equal to that set by a)
//    c = 0 for pristine Navionics charts, 1 for Sonar Charts
// TRANSPARENT parameter: FALSE for non-layer, TRUE for layer
// UGC parameter: FALSE for pristine Navionics charts, TRUE for additinal user-generated content icons

function GetNavToken: AnsiString;
var
  VTimeStamp: AnsiString;  
  VResponseCode: Cardinal;
  VResponseHeader, VResponseData: AnsiString;
  VRequestUrl, VRequestHeader, VPostData: AnsiString;
begin
  Result := 'ERROR_1';
  
  if ScriptBuffer <> '' then begin
    Result := ScriptBuffer;
    Exit;
  end;
  
  if Assigned(Downloader) then begin
    VTimeStamp := IntToStr(GetUnixTime);
    VRequestUrl := 'https://backend.navionics.io/tile/get_key/Navionics_internalpurpose_00001/webapiv2.navionics.com?_=' + VTimeStamp;
    VRequestHeader := '';
    VPostData := '';
    VResponseHeader := '';
    VResponseData := '';
 
    VResponseCode := Downloader.DoHttpRequest(VRequestUrl, VRequestHeader, VPostData, VResponseHeader, VResponseData);
 
    if VResponseCode = 200 then begin
      ScriptBuffer := VResponseData;
      Result := ScriptBuffer;
    end else begin
      ScriptBuffer := 'ERROR_2';
    end; 
  end;

end;

begin   
  ResultURL:=GetURLBase + IntToStr(GetZ-1) + '/' + IntToStr(GetX) + '/' + IntToStr(GetY) + '?LAYERS=config_1_10.00_0&TRANSPARENT=FALSE&UGC=FALSE&navtoken=' + GetNavToken;
end.