#include <GL/glui.h>

extern void setCamera();
extern void reset();

extern bool  showHandles;
extern bool  showGrid;
extern float handleSize;
extern float pixPerMeter;

GLUI *ui = NULL;
GLUI_Spinner *sizeSpinner;
GLUI_Spinner *scaleSpinner;

//
// These two variables are needed for compatibility.
// GLUI uses int's, while we use bool's.
//
int localShowHandles;
int localShowGrid;

enum {SHOW_HANDLE, SHOW_GRID, HANDLE_SIZE, SCALE, RESET, QUIT};

///////////////////////////////////////////////////////////
//
// Tell the UI's variables that the corresponding
// variables in the program have changed.
//
///////////////////////////////////////////////////////////


void syncVars() {
  if (ui != NULL) {
	sizeSpinner ->set_float_val(handleSize);
	scaleSpinner->set_float_val(pixPerMeter);
  }
}

///////////////////////////////////////////////////////////
//
// This is called when the user interacts with a
// widget on the user interface (UI).
// The ID parameter identifies which widget was affected.
//
///////////////////////////////////////////////////////////

void handleGLUIEvent( int ID ) {
  switch (ID) {
  case SHOW_HANDLE:
	showHandles = (localShowHandles != 0);
    glutPostRedisplay();
	break;

  case SHOW_GRID:
	showGrid = (localShowGrid != 0);
    glutPostRedisplay();
	break;

  case HANDLE_SIZE:
    glutPostRedisplay();
	break;

  case SCALE:
	setCamera();
    glutPostRedisplay();
	break;

  case RESET:
	reset();
	setCamera();
	syncVars();
	glutPostRedisplay();
	break;

  case QUIT:
	exit(0);

  }
}

///////////////////////////////////////////////////////////
//
// Set up the graphical user interface (UI),
// Which includes two checkboxes, two spinners,
// and two buttons.
//
///////////////////////////////////////////////////////////

void setupUI (int mainWindowID) {
  localShowHandles = showHandles;
  localShowGrid    = showGrid;

  ui = GLUI_Master.create_glui( "Rectangle Controls", 0 );

  ui->add_checkbox("Show Handles",
                   &localShowHandles, SHOW_HANDLE,
                   handleGLUIEvent);

  ui->add_checkbox("Show Grid",
                   &localShowGrid, SHOW_GRID,
                   handleGLUIEvent);

  sizeSpinner =	ui->add_spinner("Handle Size",
                    GLUI_SPINNER_FLOAT, &handleSize,
					HANDLE_SIZE, handleGLUIEvent );
  sizeSpinner->set_float_limits(0.01, 0.1, GLUI_LIMIT_CLAMP);

  scaleSpinner = ui->add_spinner("Pixels/meter",
                    GLUI_SPINNER_FLOAT, &pixPerMeter,
				    SCALE, handleGLUIEvent );

  ui->add_button("Reset", RESET, handleGLUIEvent);
  ui->add_button("Quit", QUIT, handleGLUIEvent);

  ui->set_main_gfx_window( mainWindowID );
  GLUI_Master.set_glutIdleFunc( NULL );

  glutMainLoop();
}