// OpenGL Tutorial
// Events.c - TJ VERSION
// http://www.eecs.tulane.edu/www/Terry/OpenGL/Introduction.html
/*************************************************************************
This example extends Hello_World.c to accept and handle events.  The
user should try produce each of the following events: key press, mouse
movement, mouse button press, mouse button release, reshape window, and
expose window.
*************************************************************************/

// gcc events.c -lm -L/usr/lib -lGLU  -lGL -lglut  -L/usr/X11R6/lib -lX11 -lXext -lXi -lXmu

#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <GL/glut.h>

void init() {

	// Clear the window
	glClear(GL_COLOR_BUFFER_BIT);
}

void reshape(int width, int height) {

	printf("Got a Reshape Event");
	printf(":\t width = %d height = %d\n", width, height);

	// Set the new viewport size
	glViewport(0, 0, (GLint)width, (GLint)height);

	// Clear the window
	glClear(GL_COLOR_BUFFER_BIT);
}

void keypressed(unsigned char key, int x, int y) {

	printf("Got a Key Pressed Event ");
	printf("at:\t x = %d, y = %d\n", x, y);

	if (key == (unsigned char) 27)
		exit(0);
}

void mouseButtonPress(int button, int state, int x, int y) {

	printf("Got a Mouse Keypressed Event");
	printf(":\t x = %d, y = %d, button = ", x, y);

	switch (state) {
		case GLUT_UP : printf("UP\t");
			break;
		case GLUT_DOWN : printf("DOWN\t");
			break;
	}
	switch (button) {
		case GLUT_LEFT_BUTTON : printf("left\n");
			break;
		case GLUT_RIGHT_BUTTON : printf("right\n");
			break;
		case GLUT_MIDDLE_BUTTON : printf("middle\n");
			break;
		default : printf("none\n");
			break;
	}

}

void mouseMoveNoButtonPress(int x, int y) {

	printf("Got a Mouse Move Event");
	printf(":\t x = %d, y = %d, no button pressed\n", x, y);

}

void mouseMoveWithButtonPress(int x, int y) {

	printf("Got a Mouse Move Event");
	printf(":\t x = %d, y = %d, with button pressed\n", x, y);

}

void specialKeyPress(int key, int x, int y) {

	printf("Got a Special Keypressed Event");
	printf(":\t x = %d, y = %d ", x, y);

	switch (key) {
		case GLUT_KEY_LEFT : printf("LEFT ARROW\n");
			break;
		case GLUT_KEY_UP : printf("UP ARROW\n");
			break;
		case GLUT_KEY_RIGHT : printf("RIGHT ARROW\n");
			break;
		case GLUT_KEY_DOWN : printf("DOWN ARROW\n");
			break;
		case GLUT_KEY_INSERT : printf("INSERT\n");
			break;
		case GLUT_KEY_HOME : printf("HOME\n");
			break;
		case GLUT_KEY_F1 : printf("F1\n");
			break;
	}

	// THE ESCAPE, BACKSPACE, and DELETE keys are generated as an ASCII
	// character
}


void draw(void) {

	printf("Got a Display Event\n");

	// Set the drawing color
	glColor3f(1.0, 1.0, 1.0);

	// Specify which primitive type is to be drawn
	glBegin(GL_POLYGON);
		// Specify verticies in quad
		glVertex2f(-0.5, -0.5);
		glVertex2f(-0.5, 0.5);
		glVertex2f(0.5, 0.5);
		glVertex2f(0.5, -0.5);
	glEnd();

	// Flush the buffer to force drawing of all objects thus far
	glFlush();
}

int main(int argc, char **argv) {

	// Open a window and name it
	// Open a window, name it "Events"
	glutInit(&argc, argv);  
	glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB);
	glutInitWindowSize(400, 400); 
	glutInitWindowPosition(200,200); 
	glutCreateWindow("Events");	
	
	// Set the clear color to black
	glClearColor(0.0, 0.0, 0.0, 0.0);

	// Assign expose() to be the function called whenever
	// an expose event occurs
	init();

	// Assign reshape() to be the function called whenever 
	// a reshape event occurs
	glutReshapeFunc(reshape);

	// Assign key_down() to be the function called whenever
	// a key is pressed
	glutKeyboardFunc(keypressed);

	// Assign mouse_down() to be the function called whenever
	// a mouse button is pressed
	glutMouseFunc(mouseButtonPress);

	// Assign mouse_move() to be the function called whenever
	// the mouse is moved
	glutMotionFunc(mouseMoveWithButtonPress);
	glutPassiveMotionFunc(mouseMoveNoButtonPress);
	glutSpecialFunc(specialKeyPress);

	// Assign draw() to be the function called whenever a display
	// event occurs, generally after a resize or expose event
	glutDisplayFunc(draw);

	// Assign idle() to be the function called whenever there 
	// are no events, NOT USED IN THIS EXAMPLE
//	tkIdleFunc(idle);

	// Pass program control to tk's event handling code
	// In other words, loop forever
	glutMainLoop();

	return 0;
}