unit sDBComboBox;
{$I sDefs.inc}

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls, DBCtrls, sConst, sUtils, sGraphUtils,
  sGlyphUtils, math, sStyleEdits;

type
  TsDBComboBox = class(TDBComboBox)
  private
    FAlignment : TAlignment;
    FGlyphMode: TsGlyphMode;
    FButtonMargin: integer;

    function ButtonRect: TRect;
    procedure CNCommand (var Message: TWMCommand); message CN_COMMAND;
    procedure WMPaint (var Message: TWMPaint); message WM_PAINT;
    procedure WMNCPaint (var Message: TWMPaint); message WM_NCPAINT;

    procedure SetAlignment(const Value: TAlignment);
    procedure SetButtonMargin(const Value: integer);
  protected
    FActive : boolean;
    FCharsInCode : integer;
    FsStyle : TsStyle;
    FUseItemIndex : boolean;
    BorderStyle : TFormBorderStyle;
    FDefBmpName : string;

    procedure DropDown; override;
    function GetClientRect: TRect; override;

    procedure WndProc (var Message: TMessage); override;
    procedure CreateWnd; override;
  public
    FChildHandle: HWND;
    FDefListProc: Pointer;
    FListHandle: HWND;
    FListInstance: Pointer;
    FDropDown : boolean;

    constructor Create(AOwner:TComponent); override;
    destructor Destroy; override;

    property Color;
    procedure Invalidate; override;
    procedure InvalidateSelection;
    procedure PaintButton;
    function ButtonWidth : integer;
    function ButtonHeight : integer;

    procedure RedrawBorders;
    procedure WriteText;
    property Alignment : TAlignment read FAlignment write SetAlignment;
    property CharsInCode:integer read FCharsInCode write FCharsInCode;
    property UseItemIndex : boolean read FUseItemIndex write FUseItemIndex;
    property ButtonMargin : integer read FButtonMargin write SetButtonMargin default 3;
  published
    property sStyle:TsStyle read FsStyle write FsStyle;
    property GlyphMode : TsGlyphMode read FGlyphMode write FGlyphMode;
  end;

//var
//  COMBO, bTemp : TBitmap;

implementation

uses sCustomComboBox;

{ TsDBComboBox }

function TsDBComboBox.ButtonHeight: integer;
begin
  Result := bTemp.Height div 2;
end;

function TsDBComboBox.ButtonRect: TRect;
begin
  if GlyphMode.UseDefaultGlyph or (GlyphMode.Glyph.Width < 1) then begin
    bTemp := COMBO;
  end
  else begin
    bTemp := GlyphMode.Glyph;
  end;
  Result := Rect(Width - ButtonWidth - ButtonMargin,
                 (Height - ButtonHeight) div 2,
                 Width - ButtonMargin,
                 Height - (Height - ButtonHeight) div 2);
end;

function TsDBComboBox.ButtonWidth: integer;
begin
  Result := bTemp.Width div 3;
end;

procedure TsDBComboBox.CNCommand(var Message: TWMCommand);
begin
  Case Message.NotifyCode of
    CBN_CLOSEUP: begin
      DroppedDown := False;
    end;
  end;
  inherited;
end;

constructor TsDBComboBox.Create(AOwner: TComponent);
begin
  inherited Create(AOwner);
  ControlStyle := ControlStyle - [csFixedHeight, csFramed] + [csOpaque];
  TControlCanvas(Canvas).Control := self;
  FDropDown := False;

  ParentColor := False;

  FsStyle := TsStyle.Create(Self);
  FsStyle.COC := COC_TsDBComboBox;
  FButtonMargin := 3;

  FDefBmpName := 'SCO1';
  FGlyphMode := TsGlyphMode.Create(Self);

  OnKeyDown := sStyle.OnKeyDown;
  FDefListProc := nil;
  ItemHeight := 13;

  CharsInCode := 0;
  UseItemIndex := False;
  DropDownCount := 16;
  DoubleBuffered := True;
end;

procedure TsDBComboBox.CreateWnd;
begin
  inherited;
end;

destructor TsDBComboBox.Destroy;
begin
  FreeAndNil(FsStyle);
  FreeAndNil(FGlyphMode);
  inherited Destroy;
end;

procedure TsDBComboBox.DropDown;
begin
  FDropDown := True;
  inherited;
end;

function TsDBComboBox.GetClientRect: TRect;
begin
  Result := Rect(0, 0, Width, Height);
  InflateRect(Result, -4, - 4);
end;

procedure TsDBComboBox.Invalidate;
begin
  if (csDesigning in ComponentState) and Assigned(FsStyle) then begin
    FsStyle.BGChanged := True;
  end;
  Color := sStyle.GetActiveColor;
  inherited Invalidate;
end;

procedure TsDBComboBox.InvalidateSelection;
begin
//
end;

procedure TsDBComboBox.PaintButton;
var
  b : TBitmap;
  R : TRect;
  c : TsColor;
  tc : TColor;
  function CurrentMaskRect : TRect; begin
    if DroppedDown then begin
      Result := Rect(2 * ButtonWidth, 0, 3 * ButtonWidth - 1, ButtonHeight - 1);
    end
    else if sStyle.ControlIsActive then begin
      Result := Rect(ButtonWidth, 0, 2 * ButtonWidth - 1, ButtonHeight - 1);
    end
    else begin
      Result := Rect(0, 0, ButtonWidth - 1, ButtonHeight - 1);
    end;
  end;
begin
  c.C := sStyle.GetActiveColor;
  c.C := sStyle.GetActiveColor;

  // Painting on the bitmap B
  b := TBitmap.Create;
  try
    R := ButtonRect;

    b.PixelFormat := pf24Bit;
    b.Width := ButtonWidth;
    b.Height := ButtonHeight;

    b.Canvas.Brush.Color := c.c;
    b.Canvas.FillRect(Rect(0, 0, b.Width, b.Height));


    tc := bTemp.Canvas.Pixels[0, bTemp.Height - 1];
    CopyByMask(
               Rect(0, 0, bTemp.Width - 1, bTemp.Height - 1),
               CurrentMaskRect,
               b,
               bTemp, EmptyCI);

    tc := b.Canvas.Pixels[0, b.Height - 1];
    if Enabled then begin
      if not sStyle.ControlIsActive then begin
        if GlyphMode.Grayed then begin
          GrayScaleTrans(b, TsColor(tc));
        end;
        if GlyphMode.Blend > 0 then begin
          BlendTransBitmap(b, GlyphMode.Blend / 100, c, TsColor(tc));
        end;
      end;
    end
    else begin
      BlendTransBitmap(b, 0.75, c, TsColor(tc));
{
      DisBmpColor(b, tc);
      b.Transparent := True;
      b.TransparentColor := clFuchsia;
}
    end;


    R := ButtonRect;

    tc := b.Canvas.Pixels[0, b.Height - 1];
    Canvas.Draw(R.Left, R.Top, b);
  finally
    FreeAndNil(b);
  end;
end;

procedure TsDBComboBox.RedrawBorders;
var
  R{, rT}: TRect;
  c : TColor;
begin
  c := sStyle.GetActiveColor;
  if (Focused or sStyle.FFocused) then begin
    R := GetClientRect;
//    R := Rect(0, 0, Width, Height);
    InflateRect(R, 1, 1);
    dec(R.Top);
    dec(R.Left);
    if Style = csDropDownList then begin
      Canvas.Brush.Color := C;//clHighLight;
      Canvas.FillRect(R);
      Canvas.TextRect(R, R.Left + 1, R.Top + 1, Text);
      inc(R.Top);
      inc(R.Left);
    end
    else begin
      Canvas.Brush.Color := C;
      Canvas.FillRect(R);
      Canvas.TextRect(R, R.Left + 1, R.Top + 1, Text);
    end;
  end
  else begin
    WriteText;
  end;
  sStyle.RedrawBorder;
  if (Style <> csSimple) then PaintButton;
end;

procedure TsDBComboBox.SetAlignment(const Value: TAlignment);
begin
  if FAlignment <> Value then begin
    FAlignment := Value;
    sStyle.Invalidate;
  end;
end;

procedure TsDBComboBox.SetButtonMargin(const Value: integer);
begin
  if FButtonMargin <> Value then begin
    FButtonMargin := Value;
  end;
end;

procedure TsDBComboBox.WMNCPaint(var Message: TWMPaint);
begin
  Message.Result := 1;
end;

procedure TsDBComboBox.WMPaint(var Message: TWMPaint);
var
  R, bR: TRect;
  DC: HDC;
  PS: TPaintStruct;
  WinBrush: HBRUSH;
begin
  if (csDestroying in ComponentState) or (csLoading in ComponentState) then Exit;
  Color := sStyle.GetActiveColor;
  DC := BeginPaint(Handle, PS);
  try
    R := PS.rcPaint;
    R.Right := min(Width - 1, R.Right);
    WinBrush := CreateSolidBrush(ColorToRGB(sStyle.GetActiveColor));

    FillRect(DC, R, WinBrush);
    bR := ButtonRect;

    if IntersectRect(bR, bR, PS.rcPaint) then PaintButton;

    ExcludeClipRect(DC, Width - ButtonWidth - 2, 0, Width, Height);
    if (Style = csDropDown) and DroppedDown then begin
      R := ClientRect;
      InflateRect(R, -2, -2);
      R.Right := Width;
      Canvas.Brush.Color := sStyle.GetActiveColor;
      Canvas.FrameRect(R);
    end
    else begin
      if Style <> csDropDown then InvalidateSelection;
    end;
  finally
    EndPaint(Handle, PS);
  end;
  RedrawBorders;
  DeleteObject(WinBrush);
  Message.Result := 1;
end;

procedure TsDBComboBox.WndProc(var Message: TMessage);
begin
  if Assigned(FsStyle) then FsStyle.WndProc(Message);
  if Message.Result <> 1 then inherited;
end;

procedure TsDBComboBox.WriteText;
var
  Flags: Longint;
  R : TRect;
begin
  if Text <> '' then begin
    Flags := 0;
    Canvas.Font.Assign(Font);
    R := ClientRect;
    dec(R.Left);
    dec(R.Top);
    dec(R.Right, ButtonWidth);

    case Alignment of
      taLeftJustify : begin
        Flags := DT_LEFT;
      end;
      taRightJustify : begin
        Flags := DT_RIGHT;
      end;
      taCenter : begin
        Flags := DT_CENTER;
      end
    end;
    Flags := Flags or DT_EXPANDTABS or DT_VCENTER or DT_SINGLELINE;
    Flags := DrawTextBiDiModeFlags(Flags);

    Canvas.Pen.Style := psSolid;
    Canvas.Brush.Style := bsClear;
    DrawText(Canvas.Handle, PChar(Text), Length(Text), R, Flags);
  end;
end;

end.