//Partial Lab 4 solution
//Click and move portion only
//Alan Jamieson

#include <GL/glut.h>

GLfloat xyz[3] = {0.0, 0.0, 0.0};
GLfloat theta[3] = {0.0, 0.0, 0.0};
GLint mousepos[2] = {0,0};
GLfloat size = 100;
int inflag = 0;

void myinit(){
	glColor3f(0.0, 1.0, 0.0);
	glClearColor(0.0,0.0,0.0,0.0);
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glOrtho(0.0, 500.0, 500.0, 0.0, 0, 500.0);
	glMatrixMode(GL_MODELVIEW);
}

void display(){
	glClear(GL_COLOR_BUFFER_BIT);
	glLoadIdentity();
	glRotatef(theta[0], 1.0, 0.0, 0.0);
	glRotatef(theta[1], 0.0, 1.0, 0.0);
	glRotatef(theta[2], 0.0, 0.0, 1.0);
	glTranslatef(xyz[0], xyz[1], xyz[2]);
	glutWireCube(size);
	glFlush();
}


//dead simple cursor inbound detection
int inbounds(){
	if(mousepos[0] < (xyz[0] + size/2) && mousepos[0] > (xyz[0] - size/2))
		if(mousepos[1] < (xyz[1] + size/2) && mousepos[1] > (xyz[1] - size/2))
			return(1);
	
	return(0);
}

void mymouse(int btn, int state, int x, int y){
	mousepos[0] = x;
	mousepos[1] = y;

	//check for inbounds
	if(btn == GLUT_LEFT_BUTTON && state == GLUT_DOWN && inbounds() == 1){
		inflag = 1;
	}
	
	if(btn == GLUT_RIGHT_BUTTON && state == GLUT_DOWN && inbounds() == 1){
		inflag = 1;
	}
	
	//upon release, move the cube to the cursor
	if(btn == GLUT_LEFT_BUTTON && state == GLUT_UP && inflag == 1){
		inflag = 0;
		xyz[0] = x;
		xyz[1] = y;
	}
	
	if(btn == GLUT_RIGHT_BUTTON && state == GLUT_UP && inflag == 1){
		inflag = 0;
	}
	
	//update the display
	glutPostRedisplay();
	
}

int main(int argc, char **argv){
	glutInit(&argc, argv);
	glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
	glutInitWindowSize(500, 500);
	glutCreateWindow("Lab 4 Solution");
	glutDisplayFunc(display);
	glutMouseFunc(mymouse);
	myinit();
	glutMainLoop();
	
	return(0);
}