{ TransSkel "hello, world" application in Pascal }

{ Presents a window with "Hello, world." displayed centered in the window }
{ when the window is active, and "Goodbye, world." when the window is }
{ inactive (e.g., when the application is suspended, or when the "About" }
{ alert comes up). }

{ 04 Feb 94 Version 1.00, Paul DuBois }

program Hello;

	uses
		TransSkel;

	const

{ strings that appear in window }

		hello = 'Hello, world.';
		goodbye = 'Goodbye, world.';

{ resource numbers }

		aboutAlrtRes = 1000;				{ About box }
		fileMenuNum = skelAppleMenuID + 1;	{ File menu }

{ File menu item numbers }

		quit = 1;

	var

		fileMenu: MenuHandle;

		phrase: Str255;				{ current phrase }


{--------------------------------------------------------------------}
{ Menu handling procedures }
{--------------------------------------------------------------------}

{ Handle selection of "About Hello..." item from Apple menu }

	procedure DoAppleMenu (item: Integer);
		var
			ignore: Integer;
	begin
		ignore := SkelAlert(aboutAlrtRes, SkelDlogFilter(nil, true), skelPositionOnParentDevice);
		SkelRmveDlogFilter;
	end;


{ Process selection from File menu }

	procedure DoFileMenu (item: Integer);
	begin
		case item of
			quit: 
				SkelStopEventLoop;
		end;
	end;


{ Initialize menus.  Tell TransSkel to process the Apple menu }
{ automatically, and associate the proper procedure with the }
{ File menu. }

	procedure SetupMenus;
		var
			ignore: Boolean;
	begin
		SkelApple('About HelloÉ', @DoAppleMenu);
		fileMenu := NewMenu(fileMenuNum, 'File');
		AppendMenu(fileMenu, 'Quit/Q');
		ignore := SkelMenu(fileMenu, @DoFileMenu, nil, false, false);

		DrawMenuBar;
	end;


{--------------------------------------------------------------------}
{ Window handling procedures }
{--------------------------------------------------------------------}

{ Draw grow box of window in lower right hand corner }

	procedure DrawGrowBox (w: WindowPtr);
		var
			oldClip: RgnHandle;
			r: Rect;
	begin
		r := w^.portRect;
		r.left := r.right - 15;			{ draw only in corner }
		r.top := r.bottom - 15;
		oldClip := NewRgn;
		GetClip(oldClip);
		ClipRect(r);
		DrawGrowIcon(w);
		SetClip(oldClip);
		DisposeRgn(oldClip);
	end;


	procedure Update (resized: Boolean);
		var
			w: WindowPtr;
			r: Rect;
			h, v: Integer;
	begin
		GetPort(w);
		r := w^.portRect;
		EraseRect(r);
		v := (r.top + r.bottom) div 2;
		h := (r.left + r.right - StringWidth(phrase)) div 2;
		MoveTo(h, v);
		DrawString(phrase);
		DrawGrowBox(w);
	end;


{ Normally the grow icon is drawn on a change of activation state, but since }
{ the entire portRect is invalidated here, everything will be redrawn by }
{ Update(), anyway, including the grow box.  So don't bother here. }

	procedure Activate (active: Boolean);
		var
			w: WindowPtr;
	begin
		GetPort(w);
		if (active) then
			phrase := hello
		else
			phrase := goodbye;
		InvalRect(w^.portRect);
	end;


	procedure Clobber;
		var
			w: WindowPtr;
	begin
		GetPort(w);
		DisposeWindow(w);
	end;


{ Read window from resource file and install handler for it.  Mouse }
{ and key clicks are ignored.  There is no close proc since the window }
{ doesn't have a close box.  There is no idle proc since nothing is }
{ done while the window is in front (all the things that are done are }
{ handled by TransSkel). }

	procedure WindInit;
		var
			w: WindowPtr;
			bounds: Rect;
			ignore: Boolean;
	begin
		phrase := hello;
		SetRect(bounds, 0, 0, 200, 100);
		if (SkelQuery(skelQHasColorQD) <> 0) then
			w := NewCWindow(nil, bounds, 'Howdy', false, documentProc + 8, WindowPtr(-1), false, 0)
		else
			w := NewWindow(nil, bounds, 'Howdy', false, documentProc + 8, WindowPtr(-1), false, 0);
		SkelPositionWindow(w, skelPositionOnMainDevice, FixRatio(1, 2), FixRatio(1, 5));
		ignore := SkelWindow(w, nil, nil, @Update, @Activate, nil, @Clobber, nil, false);
		TextFont(0);		{ select system font in default size }
		TextSize(0);
		SelectWindow(w);
		ShowWindow(w);
	end;


begin
	SkelInit(nil);
	SetupMenus;
	WindInit;
	SkelEventLoop;
	SkelCleanup;
end.