unit InteractiveFinChartForm;

interface

uses
  System.SysUtils, System.Classes, System.Math, System.DateUtils,
  Vcl.Forms, Vcl.Controls, Vcl.StdCtrls, Vcl.ExtCtrls,
  Atlas.FinData, Atlas.FinChart;

type
  TFinChartForm = class(TForm)
  private
    FChart: TAtlasFinChart;
    FStatus: TLabel;
    FStyle: TComboBox;
    FLog, FLive: TCheckBox;
    FTimer: TTimer;
    FTicks: Integer;
    function AddButton(AParent: TWinControl; ALeft: Integer; const ACaption: string; AOnClick: TNotifyEvent): TButton;
    procedure FillBars(Count: Integer);
    procedure ZoomInClick(Sender: TObject);
    procedure ZoomOutClick(Sender: TObject);
    procedure ShowAllClick(Sender: TObject);
    procedure NewestClick(Sender: TObject);
    procedure StyleChanged(Sender: TObject);
    procedure LogChanged(Sender: TObject);
    procedure LiveChanged(Sender: TObject);
    procedure TimerTick(Sender: TObject);
    procedure CrosshairMoved(Sender: TObject; BarIndex: Integer);
    procedure ViewChanged(Sender: TObject);
  public
    constructor Create(AOwner: TComponent); override;
  end;

implementation

constructor TFinChartForm.Create(AOwner: TComponent);
var
  Bar: TPanel;
  Price: TAtlasFinPane;
begin
  inherited CreateNew(AOwner);
  ClientWidth := 1100;
  ClientHeight := 720;
  Position := poScreenCenter;

  Bar := TPanel.Create(Self);
  Bar.Parent := Self;
  Bar.Align := alTop;
  Bar.Height := 40;
  Bar.BevelOuter := bvNone;
  AddButton(Bar, 8, 'Zoom in', ZoomInClick);
  AddButton(Bar, 92, 'Zoom out', ZoomOutClick);
  AddButton(Bar, 176, 'Show all', ShowAllClick);
  AddButton(Bar, 260, 'Newest', NewestClick);
  FStyle := TComboBox.Create(Self);
  FStyle.Parent := Bar;
  FStyle.SetBounds(356, 8, 110, 24);
  FStyle.Style := csDropDownList;
  FStyle.Items.CommaText := 'Candles,OHLC,"Close line","Close area"';
  FStyle.ItemIndex := 0;
  FStyle.OnChange := StyleChanged;
  FLog := TCheckBox.Create(Self);
  FLog.Parent := Bar;
  FLog.SetBounds(480, 10, 110, 20);
  FLog.Caption := 'Logarithmic';
  FLog.OnClick := LogChanged;
  FLive := TCheckBox.Create(Self);
  FLive.Parent := Bar;
  FLive.SetBounds(596, 10, 90, 20);
  FLive.Caption := 'Live bars';
  FLive.OnClick := LiveChanged;
  FStatus := TLabel.Create(Self);
  FStatus.Parent := Bar;
  FStatus.SetBounds(700, 12, 390, 20);
  FStatus.Caption := 'Move the mouse over the chart';

  FTimer := TTimer.Create(Self);
  FTimer.Interval := 400;
  FTimer.Enabled := False;
  FTimer.OnTimer := TimerTick;

  FChart := TAtlasFinChart.Create(Self);
  FChart.Parent := Self;
  FChart.Align := alClient;
  FChart.ValueFormat := '0.00';
  FChart.OnCrosshair := CrosshairMoved;
  FChart.OnViewChange := ViewChanged;
  Price := FChart.Panes.Add('Price', 300);
  Price.Studies.Add(skCandles);
  Price.Studies.Add(skBollinger, 20);
  Price.Studies.Add(skEMA, 50).LineWidth := 2;
  FChart.Panes.Add('Volume', 90).Studies.Add(skVolume);
  FChart.Panes.Add('MACD', 110).Studies.Add(skMACD);
  FChart.Panes.Add('RSI', 90).Studies.Add(skRSI, 14);
  FillBars(260);
  // Start on the newest 120 bars; this view follows live bars as they arrive.
  FChart.ZoomTo(FChart.Data.Count - 120, 120);
  ActiveControl := FChart;
end;

function TFinChartForm.AddButton(AParent: TWinControl; ALeft: Integer; const ACaption: string;
  AOnClick: TNotifyEvent): TButton;
begin
  Result := TButton.Create(Self);
  Result.Parent := AParent;
  Result.SetBounds(ALeft, 8, 80, 24);
  Result.Caption := ACaption;
  Result.OnClick := AOnClick;
end;

procedure TFinChartForm.FillBars(Count: Integer);
var
  Day: TDateTime;
  Price, Open, Close: Double;
  I: Integer;
begin
  RandSeed := 7; // the same walk on every run
  Day := EncodeDate(2025, 9, 1);
  Price := 250;
  FChart.Data.BeginUpdate;
  try
    I := 0;
    while I < Count do
    begin
      if DayOfTheWeek(Day) <= 5 then
      begin
        Open := Price * (1 + (Random - 0.5) * 0.008);
        Close := Open * (1 + (Random - 0.49) * 0.03);
        FChart.Data.Add(Day, Open, Max(Open, Close) * (1 + Random * 0.01), Min(Open, Close) * (1 - Random * 0.01),
          Close, Round(800000 + Random * 600000));
        Price := Close;
        Inc(I);
      end;
      Day := Day + 1;
    end;
  finally
    FChart.Data.EndUpdate;
  end;
end;

procedure TFinChartForm.ZoomInClick(Sender: TObject);
begin
  FChart.ZoomBy(0.8, FChart.FirstBar + FChart.VisibleBars div 2);
end;

procedure TFinChartForm.ZoomOutClick(Sender: TObject);
begin
  FChart.ZoomBy(1.25, FChart.FirstBar + FChart.VisibleBars div 2);
end;

procedure TFinChartForm.ShowAllClick(Sender: TObject);
begin
  FChart.ShowAll;
end;

procedure TFinChartForm.NewestClick(Sender: TObject);
begin
  FChart.ScrollBy(MaxInt); // clamps to the newest bar
end;

procedure TFinChartForm.StyleChanged(Sender: TObject);
const
  Kinds: array[0..3] of TAtlasStudyKind = (skCandles, skOhlc, skCloseLine, skCloseArea);
begin
  FChart.Panes[0].Studies[0].Kind := Kinds[FStyle.ItemIndex];
end;

procedure TFinChartForm.LogChanged(Sender: TObject);
begin
  FChart.Panes[0].Logarithmic := FLog.Checked;
end;

procedure TFinChartForm.LiveChanged(Sender: TObject);
begin
  FTimer.Enabled := FLive.Checked;
end;

procedure TFinChartForm.TimerTick(Sender: TObject);
var
  Last: TAtlasBar;
  Day: TDateTime;
  Close: Double;
begin
  Last := FChart.Data[FChart.Data.Count - 1];
  Inc(FTicks);
  if FTicks mod 8 = 0 then
  begin
    // A new bar on the next weekday. A view parked on the newest bar follows it,
    // but following does not raise OnViewChange, so refresh the caption here.
    Day := Last.Time + 1;
    while DayOfTheWeek(Day) > 5 do Day := Day + 1;
    FChart.Data.Add(Day, Last.Close, Last.Close, Last.Close, Last.Close, 0);
    ViewChanged(FChart);
  end
  else
  begin
    // The forming bar moves: only the newest bar is replaced.
    Close := Last.Close * (1 + (Random - 0.5) * 0.01);
    FChart.Data.UpdateLast(Last.Open, Max(Last.High, Close), Min(Last.Low, Close), Close, Last.Volume + 25000);
  end;
end;

procedure TFinChartForm.CrosshairMoved(Sender: TObject; BarIndex: Integer);
var
  Bar: TAtlasBar;
  Rsi: Double;
  RsiText: string;
begin
  if BarIndex < 0 then
  begin
    FStatus.Caption := '';
    Exit;
  end;
  Bar := FChart.Data[BarIndex];
  // Study lines are cached against the data version, so this costs nothing.
  Rsi := FChart.Panes[3].Studies[0].Lines(FChart.Data)[0][BarIndex];
  if IsNan(Rsi) then RsiText := '-' else RsiText := FormatFloat('0.0', Rsi);
  FStatus.Caption := Format('%s  O %.2f  H %.2f  L %.2f  C %.2f  Vol %.0f  RSI %s',
    [FormatDateTime('ddddd', Bar.Time), Bar.Open, Bar.High, Bar.Low, Bar.Close, Bar.Volume, RsiText]);
end;

procedure TFinChartForm.ViewChanged(Sender: TObject);
begin
  Caption := Format('Atlas Fin: bars %d to %d of %d (drag to scroll, wheel to zoom, drag a pane border, double-click for all)',
    [FChart.FirstBar + 1, FChart.FirstBar + FChart.VisibleBars, FChart.Data.Count]);
end;

end.