unit GroupFreqUnit;

{$mode objfpc}{$H+}

interface

uses
  Classes, SysUtils, LResources, Forms, Controls, Graphics, Dialogs, Buttons,
  ExtCtrls, StdCtrls, LCLVersion,
  TASources,
  Globals, MainUnit, MainDM, BasicStatsChartFormUnit;

type

  { TGroupFreqForm }

  TGroupFreqForm = class(TBasicStatsChartForm)
    ShowValuesChk: TCheckBox;
    GrpInBtn: TBitBtn;
    GrpOutBtn: TBitBtn;
    GrpVarEdit: TEdit;
    HorBarsBtn: TSpeedButton;
    Label1: TLabel;
    Label2: TLabel;
    PlotOptionsGroup: TGroupBox;
    ThreeDChk: TCheckBox;
    VarList: TListBox;
    VertBarsBtn: TSpeedButton;
    procedure GrpInBtnClick(Sender: TObject);
    procedure GrpOutBtnClick(Sender: TObject);
    procedure VarListDblClick(Sender: TObject);
    procedure VarListSelectionChange(Sender: TObject; User: boolean);
  private
    FLabelsSource: TListChartSource;

  protected
    procedure AdjustConstraints; override;
    procedure Compute; override;
    procedure Plot(XLabels: StrDyneVec; FreqValues: DblDyneVec; XTitle: String);
    procedure UpdateBtnStates; override;

  public
    constructor Create(AOwner: TComponent); override;
    procedure Reset; override;

  end;

var
  GroupFreqForm: TGroupFreqForm;

implementation

{$R *.lfm}

uses
  Math,
  TAChartUtils, TACustomSeries, TASeries,
  Utils, DataProcs, ChartFrameUnit;


{ TGroupFreqForm }

constructor TGroupFreqForm.Create(AOwner: TComponent);
begin
  inherited;
  FLabelsSource := TListChartSource.Create(self);
end;


procedure TGroupFreqForm.AdjustConstraints;
begin
  ParamsPanel.Constraints.MinWidth := MaxValue( [
    4*CloseBtn.Width + 3*CloseBtn.BorderSpacing.Left,
    (PlotOptionsGroup.Width - GrpInBtn.Width div 2 + GrpVarEdit.BorderSpacing.Left)*2,
    (Max(Label1.Width, Label2.Width) + GrpvarEdit.BorderSpacing.Left) * 2
  ]);
  ParamsPanel.Constraints.MinHeight :=  PlotOptionsGroup.Top + PlotOptionsGroup.Height +
    ButtonBevel.Height + CloseBtn.BorderSpacing.Top + CloseBtn.Height;

  Constraints.MinWidth := ParamsPanel.Constraints.MinWidth + 300;
  Constraints.MinHeight := ParamsPanel.Constraints.MinHeight + ParamsPanel.BorderSpacing.Top * 2;
end;


procedure TGroupFreqForm.Compute;
var
  grpcol: integer;
  cellStr: string;
  i, numValues, valueIdx: integer;
  freq: DblDyneVec = nil;  // Could be IntDyneVec, but easier plotting with Dbl
  values: StrDyneVec = nil;
begin
  // get the variable to analyze
  grpcol := 0;
  for i := 1 to NoVariables do
    if GrpVarEdit.Text = OS3MainFrm.DataGrid.Cells[i,0] then
    begin
      grpcol := i;
      break;
    end;
  if grpcol = 0 then
  begin
     MessageDlg('No variable selected.', mtError, [mbOK], 0);
     exit;
  end;

  SetLength(values, NoCases);    // over-dimension values array; will be trimmed.
  numvalues := 0;
  for i := 1 to NoCases do
  begin
    cellStr := Trim(OS3MainFrm.DataGrid.Cells[grpcol,i]);
    if IndexOfString(values, cellStr) = -1 then begin
      values[numValues] := cellStr;
      inc(numvalues);
    end;
  end;
  SetLength(values, numValues);  // Trim values array to correct length

  // setup frequency array and count cases in each group
  SetLength(freq, numvalues);
  for i := 1 to NoCases do
  begin
    if not ValidValue(i, grpcol) then continue;
    cellStr := Trim(OS3MainFrm.DataGrid.Cells[grpcol, i]);
    valueIdx := IndexOfString(values, cellStr);
    if valueIdx > -1 then
      freq[valueIdx] := freq[valueIdx] + 1
    else
      raise Exception.Create('Value index not found.');  // this should not happen
  end;

  // Plot frequency data
  Plot(values, freq, GrpVarEdit.Text);
end;


procedure TGroupFreqForm.GrpInBtnClick(Sender: TObject);
var
  index: integer;
begin
  index := VarList.ItemIndex;
  if (index > -1) and (GrpVarEdit.Text = '') then
  begin
    GrpVarEdit.Text := VarList.Items[index];
    VarList.Items.Delete(index);
  end;
  UpdateBtnStates;
end;


procedure TGroupFreqForm.GrpOutBtnClick(Sender: TObject);
begin
  if GrpVarEdit.Text <> '' then
  begin
    VarList.Items.Add(GrpVarEdit.Text);
    GrpVarEdit.Text := '';
  end;
  UpdateBtnStates;
end;


procedure TGroupFreqForm.Plot(XLabels: StrDyneVec; FreqValues: DblDyneVec; XTitle: String);
const
  MARGIN: array[boolean] of Integer = (4, 0);
var
  ser: TBarSeries;
  YTitle: String;
  i: Integer;
begin
  // Erase the chart, if it has already been used.
  FChartFrame.Clear;
  FLabelsSource.Clear;

  // Copy XLabels to LabelsSource
  for i := 0 to High(XLabels) do
    FLabelsSource.Add(i+1, i+1, XLabels[i]);

  // Define captions -- will be applied later
  XTitle := 'Values of ' + XTitle;
  YTitle := 'Frequency';

  // Plot the frequencies
  ser := TBarSeries(FChartFrame.PlotXY(ptBars, nil, FreqValues, XLabels, nil, '', DATA_COLORS[0]));
  if ThreeDChk.Checked then
  begin
    ser.Depth := 20;
    {$IF LCL_FullVersion >= 2010000}
    ser.DepthBrightnessDelta := -30;
    {$IFEND}
  end;

  // Show/Hide series labels
  if ShowValuesChk.Checked then
  begin
    ser.Marks.Style := smsValue;
    ser.Marks.Distance := 0;
    ser.MarkPositionCentered := true;
  end else
    ser.Marks.Style := smsNone;
  ser.Marks.LinkPen.Color := clGray;

  // Hide legend
  FChartFrame.Chart.Legend.Visible := false;

  // Show XLabels along the x axis
  if HorBarsBtn.Down then
  begin
    // Rotate bars to be horizontal
    ser.AxisIndexX := 0;
    ser.AxisIndexY := 1;
    FChartFrame.SetXTitle(YTitle);
    FChartFrame.SetYTitle(XTitle);
    FChartFrame.Chart.Margins.Bottom := 4;
    FChartFrame.Chart.BottomAxis.Marks.Source := nil;
    FChartFrame.Chart.BottomAxis.Marks.Style := smsValue;
    FChartFrame.Chart.BottomAxis.Marks.Alignment := taCenter;
    FChartFrame.Chart.Margins.Left := MARGIN[HorBarsBtn.Down];
    FChartFrame.Chart.LeftAxis.Marks.Source := FLabelsSource;
    FChartFrame.Chart.LeftAxis.Marks.Style := smsLabel;
    FChartFrame.Chart.LeftAxis.Marks.Alignment := taCenter;
  end else
  begin
    ser.AxisIndexX := 1;
    ser.AxisIndexY := 0;
    FChartFrame.SetXTitle(XTitle);
    FChartFrame.SetYTitle(YTitle);
    FChartFrame.Chart.Margins.Bottom := MARGIN[HorBarsBtn.Down];
    FChartFrame.Chart.BottomAxis.Marks.Source := FLabelsSource;
    FChartFrame.Chart.BottomAxis.Marks.Style := smsLabel;
    FChartFrame.Chart.BottomAxis.Marks.Alignment := taCenter;
    FChartFrame.Chart.Margins.Left := 4;
    FChartFrame.Chart.LeftAxis.Marks.Source := nil;
    FChartFrame.Chart.LeftAxis.Marks.Style := smsValue;
    FChartFrame.Chart.LeftAxis.Marks.Alignment := taCenter;
  end;

  // Set Chart title
  FChartFrame.SetTitle('Frequency Distribution');
end;


procedure TGroupFreqForm.Reset;
var
  i: integer;
begin
  inherited;

  VarList.Clear;
  for i := 1 to NoVariables do
    VarList.Items.Add(OS3MainFrm.DataGrid.Cells[i,0]);
  GrpVarEdit.Text := '';
  UpdateBtnStates;
end;


procedure TGroupFreqForm.UpdateBtnStates;
begin
  inherited;
  GrpInBtn.Enabled := (VarList.ItemIndex > -1);
  GrpOutBtn.Enabled := (GrpVarEdit.Text <> '');
end;


procedure TGroupFreqForm.VarListDblClick(Sender: TObject);
var
  index: Integer;
begin
  index := VarList.ItemIndex;
  if (index > -1) and (GrpVarEdit.Text = '') then
  begin
    GrpVarEdit.Text := VarList.Items[index];
    Varlist.Items.Delete(index);
    UpdateBtnStates;
  end;
end;


procedure TGroupFreqForm.VarListSelectionChange(Sender: TObject; User: boolean);
begin
  UpdateBtnStates;
end;


end.