#ifndef _FG_OS_HXX
#define _FG_OS_HXX

// Plib pui needs to know at compile time what toolkit is in use.
// Change this when we move to something other than glut.
#define PU_USE_GLUT

enum { MOUSE_BUTTON_LEFT,
       MOUSE_BUTTON_MIDDLE,
       MOUSE_BUTTON_RIGHT };

enum { MOUSE_BUTTON_DOWN,
       MOUSE_BUTTON_UP };

enum { MOUSE_CURSOR_NONE,
       MOUSE_CURSOR_POINTER,
       MOUSE_CURSOR_WAIT,
       MOUSE_CURSOR_CROSSHAIR,
       MOUSE_CURSOR_LEFTRIGHT };

enum { KEYMOD_NONE     = 0,
       KEYMOD_RELEASED = 1, // Not a mod key, indicates "up" action
       KEYMOD_SHIFT    = 2,
       KEYMOD_CTRL     = 4,
       KEYMOD_ALT      = 8,
       KEYMOD_MAX      = 16 };

// A note on key codes: none are defined here.  FlightGear has no
// hard-coded interpretations of codes other than modifier keys, so we
// can get away with that.  The only firm requirement is that the
// codes passed to the fgKeyHandler function be correctly interpreted
// by the PUI library.  Users who need to hard-code key codes
// (probably not a good idea in any case) can use the pu.hxx header
// for definitions.

//
// OS integration functions
//

void fgOSInit(int* argc, char** argv);
void fgOSOpenWindow(int w, int h, int bpp, bool alpha, bool stencil,
                    bool fullscreen);
void fgOSFullScreen();
void fgOSMainLoop();

void fgSetMouseCursor(int cursor);
int  fgGetMouseCursor();
void fgWarpMouse(int x, int y);

int  fgGetKeyModifiers();

void fgRequestRedraw();

//
// Callbacks and registration API
//

typedef void (*fgIdleHandler)();
typedef void (*fgDrawHandler)();
typedef void (*fgWindowResizeHandler)(int w, int h);

typedef void (*fgKeyHandler)(int key, int keymod, int mousex, int mousey);
typedef void (*fgMouseClickHandler)(int button, int updown, int x, int y);
typedef void (*fgMouseMotionHandler)(int x, int y);

void fgRegisterIdleHandler(fgIdleHandler func);
void fgRegisterDrawHandler(fgDrawHandler func);
void fgRegisterWindowResizeHandler(fgWindowResizeHandler func);

void fgRegisterKeyHandler(fgKeyHandler func);
void fgRegisterMouseClickHandler(fgMouseClickHandler func);
void fgRegisterMouseMotionHandler(fgMouseMotionHandler func);

#endif // _FG_OS_HXX