unit X11_Screens;

{$MODE OBJFPC}
{$M+}

interface
uses X11_Objects, X11, type_fixes, xlib;

type
  TScreen = class(system.TObject) // (X11_Objects.TObject, {IScreen, X11_Objects.IObject, IInterface)
  private
    fRootWindow : IWindow;
    fDefaultVisual : IVisual;
    fScreen : PScreen;
    fDisplay : PDisplay;
  protected
    function GetRootWindow : IWindow;
    function GetDefaultDepth : TInteger;
    function GetDefaultVisual : IVisual;
    function GetWidthMM : TInteger;
    function GetHeightMM : TInteger;
    function GetWidthPixels : TInteger;
    function GetHeightPixels : TInteger; 
  published
    property RootWindow : IWindow read GetRootWindow;
    property DefaultDepth : TInteger read GetDefaultDepth;
    property DefaultVisual : IVisual read GetDefaultVisual;
    
    constructor Reuse(aDisplay : PDisplay; aScreen : PScreen; aBOwnsScreen : Boolean = False);
    
    // TODO: (can these change in the lifetime of a X server?)
    // depths.
    // default gc.
    // display cells.
    // display string.
    // #define BlackPixelOfScreen(s)
    // #define WhitePixelOfScreen(s)
    // #define DefaultColormapOfScreen(s)((s)->cmap)
    // #define DefaultDepthOfScreen(s) ((s)->root_depth)
    // #define DefaultGCOfScreen(s)    ((s)->default_gc)
    //#define CellsOfScreen(s)        (DefaultVisualOfScreen((s))->map_entries)
    //#define MinCmapsOfScreen(s)     ((s)->min_maps)
    //#define MaxCmapsOfScreen(s)     ((s)->max_maps)
    //#define DoesSaveUnders(s)       ((s)->save_unders)
    //#define DoesBackingStore(s)     ((s)->backing_store)
    //#define EventMaskOfScreen(s)    ((s)->root_input_mask) 

    property WidthMM : TInteger read GetWidthMM;
    property HeightMM : TInteger read GetHeightMM; 
    property WidthPixels : TInteger read GetWidthPixels;
    property HeightPixels : TInteger read GetHeightPixels; 
  public
    property Display : PDisplay read fDisplay;
  end;
  TScreenArray = array of TScreen;
  
implementation
uses X11_Windows, X11_Visuals;

function TScreen.GetRootWindow : IWindow;
begin
  if not Assigned(fRootWindow) then
    fRootWindow := TWindow.Reuse(Display, RootWindowOfScreen(fScreen), False);
    
  Result := fRootWindow;
end;

function TScreen.GetDefaultDepth : TInteger;
begin
  Result := DefaultDepthOfScreen(fScreen);
end;

function TScreen.GetDefaultVisual : IVisual;
begin
  if not Assigned(fDefaultVisual) then
    fDefaultVisual := X11_Visuals.TVisual.Reuse(Display, DefaultVisualOfScreen(fScreen), True);
    
  Result := fDefaultVisual;
end;

function TScreen.GetWidthMM : TInteger;
begin
  Result := WidthMMOfScreen(fScreen);
end;

function TScreen.GetHeightMM : TInteger;
begin
  Result := HeightMMOfScreen(fScreen);
end;

function TScreen.GetWidthPixels : TInteger;
begin
  Result := WidthOfScreen(fScreen);
end;

function TScreen.GetHeightPixels : TInteger; 
begin
  Result := HeightOfScreen(fScreen);
end;

constructor TScreen.Reuse(aDisplay : PDisplay; aScreen : PScreen; aBOwnsScreen : Boolean);
begin
  fDisplay := aDisplay;
  fScreen := aScreen;
end;

end.