program CovidStatistic_Plot_Validation31;
//{$APPTYPE CONSOLE}   - Refactor Separation of Concerns
// Basescript for maXbox_starter85.pdf - Tutorial 85
//www.softwareschule.ch/download/maxbox_starter85.pdf
//https://www.bbc.com/news/world-51235105

Const
   JSONUrl = 'https://pomber.github.io/covid19/timeseries.json';
   COUNTRY1 = 'Afghanistan';  //first: Afghanistan 'Sweden'; Germany Afghanistan     
   COUNTRY2 = 'Zimbabwe';    //last: Zimbabwe
   COUNTRY3 = 'Brazil';      //delete filter
   
procedure From_CloseClick(Sender: TObject; var action: TCloseAction);
  begin
    //afrm.Close;
    action:= cafree;
    writeln('Plotform closed at: '+datetimetostr(now));
  end;
   
function ConnectJSON_API: string;
var XMLhttp: OleVariant; // AsObject
begin 
  XMLhttp:= CreateOleObject('msxml2.xmlhttp')
  XMLhttp.Open('GET', JSONUrl, False)
  XMLhttp.setrequestHeader('Content-Type','application/x-www-form-urlencoded');
  XMLhttp.Send();
  result:= XMLhttp.responseText; 
  writeln('http status: '+vartostr(XMLhttp.status)); 
  XMLhttp:= unassigned;
end; 

function ChartInjector(aform: Tform): TChart; 
var Ser1: TFastLineSeries; //TPieSeries; 
begin
  result:= TChart.create(aform) 
  with result do begin
    parent:= aform;
    align:= alClient;
    Title.Text.add('SciplotSerie: '+'Worldwide Covid21 Ø');
    LeftAxis.Title.Caption:= 'Covid D Amount';
    Title.font.size:= 20;
    Ser1:= TFastLineSeries.create(result); // TPieSeries
    ser1.parentchart:= result;
    Ser1.Marks.Visible:= true;
    //Free;
  end;   
end;  

procedure JSONPlot(form1: TForm);
var chart1: TChart;  
    ajt: TJson; JObj: TJsonObject2; JArr: TJsonArray2;  
    response, clb: string; 
    cnt,cnt2,tmp,tmp2, tmp3, sumup,sumup2, startC,stopC: integer;
    tmp3d: double;
begin
  response:= ConnectJSON_API;
  //slice func like python
  startC:= pos('"'+COUNTRY1+'"',response);  
  stopC:= pos('"'+COUNTRY2+'"',response);  
  (*response:= Copy(response, startC, stopC-startC);
  response:= '{'+response+'}'; *)
  ajt:= TJson.create();
  try
    ajt.parse(response);
  except
     writeln( 'Exception: <TJson>"" parse error: {'+
     exceptiontostring(exceptiontype, exceptionparam)) 
  end;  
 
  form1.onclose:= @From_CloseClick;
  JObj:= ajt.JsonObject;
  chart1:= ChartInjector(form1); 
  clb:=''; sumup:=0; sumup2:=0;
  
  for cnt:= 0 to jobj.count-1 do begin
    clb:= Jobj.items[cnt].name
    JArr:= ajt.values[clb].asarray;
    for cnt2:= jarr.count-1 to jarr.count-1 do begin
      tmp:= jarr.items[cnt2].asObject.values['deaths'].asinteger;
      tmp2:= jarr.items[cnt2].asObject.values['confirmed'].asinteger; 
      PrintF(' %d: %d  %s',[cnt,tmp,clb]);
      PrintF(' %d: %d  %s',[cnt,tmp2,clb]);
      tmp3d:=  tmp / tmp2;        
      PrintF(' %d:     %.4f %% ',[cnt,tmp3d * 100]);
      
      sumup:= sumup+tmp;
      sumup2:= sumup2+tmp2;
      chart1.Series[0].Addxy(cnt,tmp,itoa(tmp div 1000)+' '+clb,clgreen);
    end; 
  end;
 PrintF(' WorldWide %d: Confirmed: %d', [ajt.count, sumup2]);
 PrintF(' WorldWide %d: Deaths: %d', [ajt.count, sumup]);
 PrintF(' WorldWide %d: Deathrate: %.4f', [ajt.count, (sumup / sumup2) *100]);
 ajt.Clear;
 ajt.Free;
end; 
      
begin //@main  
  //ValidateBitcoinAddress('1AGNa15ZQXAZUgFiqJ2i7Z2DPU2J6hW62i');
  
   JSONPlot(getForm2(1200, 600, clGreen, 'Sciplot4'));  
End.

ref: http://www.teechart.net/docs/teechart/vcl/TChart.0Methods.html 

https://www.buybitcoinworldwide.com/how-many-bitcoins-are-there/

 mX4 executed: 15/03/2021 20:43:46  Runtime: 0:0:4.531  Memload: 63% use
 mX4 executed: 07/05/2021 13:02:28  Runtime: 0:0:15.610  Memload: 72% use
 mX4 executed: 07/05/2021 13:04:10  Runtime: 0:0:14.329  Memload: 67% use
 WorldWide 193: Confirmed: 169296672
 WorldWide 193: Deaths: 3519492
 WorldWide 193: Deathrate: 2.0789
 mX4 executed: 29/05/2021 11:04:50  Runtime: 0:0:15.707  Memload: 71% use
 mX4 byte code executed: 29/05/2021 11:28:51  Runtime: 0:0:13.969  Memload: 74% use
ByteCode Success Message of: C:\maXbox\mX47464\maxbox4\examples\covidapp31.psb
WorldWide 193: Confirmed: 171184588
 WorldWide 193: Deaths: 3565105
 WorldWide 193: Deathrate: 2.0826
 mX4 executed: 02/06/2021 21:31:29  Runtime: 0:0:25.905  Memload: 69% use