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

// Define a constant for the value of PI
#define GL_PI 3.1415f

static float camX, camY, camZ;
static float viewX, viewY, viewZ;
static float step = 0.01f;

static float orbitDegreeZ = 0.0f;
static float orbitDegreeX = 0.0f;
static float zoom = 1.0f;


static GLfloat ambientLight[] = { 0.2f, 0.2f, 0.2f, 1.0f};
static GLfloat spotDir[] = { -1.0f, 0.0f, -1.0f };
static GLfloat lightPos[] = { 15.0f, 15.0f, 20.0f, 1.0f };
static GLfloat specref[] =  { 1.0f, 1.0f, 1.0f, 1.0f };
static GLfloat specular[] = { 1.0f, 1.0f, 1.0f, 1.0f};

static float orbitDegree = 0.0f;

GLint i = 0;




void BitmapText(int x, int y, char *string) {
	int len, i;
	glRasterPos2f( x, y );
	len = (int) strlen(string);
	for (i=0; i < len; i++) {
		glutBitmapCharacter(GLUT_BITMAP_HELVETICA_18, string[i]);
	}
}

void StrokeText(char *string) {
	int len, i;
	len = (int) strlen(string);
	for (i=0; i < len; i++) {
		glutStrokeCharacter(GLUT_STROKE_ROMAN, string[i]);
	}
} 

void drawBoard() {
	
	float x0, x1, y0, y1; 
	glPushMatrix();
	
	drawTorch();
	
	glColor3f(0.7f,1.0f, 0.7f);
	
	
	
	
	
	
			glBegin(GL_QUADS);
				glNormal3f(0.0, 0.0, 1.0);
				for ( x0= 0.0f, x1 = 0.2f; x1<60.0f; x0+=0.2f, x1+=0.2f ) {
					for (y0= 0.0f, y1 = 0.2f; y1<60.0f; y0+=0.2f, y1+=0.2f ) {
						glVertex3f(x1,y1,3.0f);
						glVertex3f( x0,y1,3.0f);
						glVertex3f( x0,y0,3.0f);
						glVertex3f(x1,y0,3.0f);
					}
				}
			glEnd();

/*
	glBegin(GL_QUADS);
		glVertex3f(20.0f,30.0f,3.0f);
		glVertex3f( 10.0f,30.0f,3.0f);
		glVertex3f( 10.0f,0.0f,3.0f);
		glVertex3f(20.0f, 0.0f,3.0f);
	glEnd();
	glBegin(GL_QUADS);
		glVertex3f(30.0f,30.0f,3.0f);
		glVertex3f( 20.0f,30.0f,3.0f);
		glVertex3f( 20.0f, 0.0f,3.0f);
		glVertex3f(30.0f, 0.0f,3.0f);
	glEnd();
	*/
	
	/*
	glBegin(GL_QUADS);
		
		glVertex3f(30.0f,30.0f,3.0f);
		glVertex3f( 0.0f,30.0f,3.0f);
		glVertex3f( 0.0f, 0.0f,3.0f);
		glVertex3f(30.0f, 0.0f,3.0f);
	glEnd();
	*/
	
	
	
	glColor3f(0.0f,0.0f,0.8f);
	glTranslatef(2.0f,20.0f,5.0f);
	glScalef(0.05f,0.05f,0.02f);
	glLineWidth(2);
	StrokeText("The light");
	
	glPopMatrix();
	
}

void drawTorch() {
	
	glPushMatrix();
	//glTranslatef(0.0f,0.0f,0.0f);
	glLightfv(GL_LIGHT0,GL_POSITION,lightPos);
	glLightfv(GL_LIGHT0,GL_SPOT_DIRECTION,spotDir);
	
	/*
	glPushMatrix();
	glTranslatef(spotDir[0], spotDir[1], spotDir[2]);
	glColor3f( 1.0f, 0.0f, 0.0f );
	glutSolidSphere(2,10,10);
	glPopMatrix();
	*/ 
	
	glColor3f( 1.0f, 1.0f, 0.0f );
	
	glPushAttrib(GL_LIGHTING_BIT);
	
	// Turn off lighting and specify a bright yellow sphere
	glTranslatef(lightPos[0], lightPos[1], lightPos[2]);
	glDisable(GL_LIGHTING);
	glutSolidSphere(4.0f,10,10);
	//glutSolidCone(0.5f,5.0f,10,10);
	//glEnable(GL_LIGHTING);
	glPopAttrib();
	
	
	
	//glutSolidCone(4.0f,6.0f,15,15);
	//glPushAttrib(GL_LIGHTING_BIT);
	glPopMatrix();
}

// Called to draw scene
void RenderScene(void)
{
  int j = 0;
  
  // Clear the window with current clearing color
  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

  glPushMatrix();
  //glRotatef(-90, 1.0f, 0.0f, 0.0f);
  
  glRotatef(-50.0 + orbitDegreeX, 1.0f, 0.0f, 0.0f);
  //glRotatef(orbitDegreeZ, 0.0f,0.0f,1.0f);
  
  glPushMatrix();
  glRotatef(90.0f, 1.0f,0.0f, 0.0f);
  drawBoard();

  glPopMatrix();
  
  glPopMatrix();  
  // Flush drawing commands
  glutSwapBuffers();
}

// This function does any needed initialization on the rendering
// context. 
void SetupRC()
{
 glEnable(GL_DEPTH_TEST);	// Hidden surface removal
	glFrontFace(GL_CCW);		// Counter clock-wise polygons face out
	glEnable(GL_CULL_FACE);		// Do not calculate inside of jet
	glShadeModel(GL_SMOOTH);

	// Light blue background
	glClearColor(0.0f, 0.0f, 0.0f, 1.0f );

	glEnable(GL_LIGHTING);
	//glLightModelfv(GL_LIGHT_MODEL_AMBIENT, ambientLight);

	// Setup and enable light 0
	//glLightfv(GL_LIGHT0, GL_AMBIENT, ambientLight);
	glLightfv(GL_LIGHT0, GL_SPECULAR, specular);
	//glLightfv(GL_LIGHT0, GL_POSITION, lightPos);

	// Specific spot effects
	// Cut off angle
	glLightf(GL_LIGHT0, GL_SPOT_CUTOFF, 60.0f);

	// Fairly shiny spot
	glLightf(GL_LIGHT0, GL_SPOT_EXPONENT, 100.0f);	

	glEnable(GL_LIGHT0);

	// Enable Material color tracking
	glEnable(GL_COLOR_MATERIAL);
	// Front material ambient and diffuse colors track glColor
	glColorMaterial(GL_FRONT, GL_AMBIENT_AND_DIFFUSE);

	// All materials hereafter have full specular reflectivity
	// with a high shine
	glMaterialfv(GL_FRONT, GL_SPECULAR, specref);
	glMateriali(GL_FRONT, GL_SHININESS, 128);

	glEnable(GL_NORMALIZE);
  
 
}



void Timer(int value)
{
  printf("Timer esemeny (%d)\n", value);
  i++;
  if( i==10 ) i= 0;
  glutPostRedisplay();
  glutTimerFunc(1000, Timer, value + 1);
}

void Idle()
{

  glutPostRedisplay();
}

void ChangeSizeOrtho(int w, int h)
{
  //GLfloat nRange = 25.0f;
  //GLfloat nRange = 30.0f;
  GLfloat nRange = 50.0f ;
  
  // Prevent a divide by zero
  if(h == 0)
    h = 1;
  
  // Set Viewport to window dimensions
  glViewport(0, 0, w, h);
  
  // Reset projection matrix stack
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  
  // Establish clipping volume (left, right, bottom, top, near, far)
  if (w <= h) 
    glOrtho (-nRange, nRange, -nRange*h/w, nRange*h/w, -nRange, nRange);
  else 
    glOrtho (-nRange*w/h, nRange*w/h, -nRange, nRange, -nRange, nRange);
  
  // Reset Model view matrix stack
  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();
}



void SpecialKeys(int key, int x, int y) {
	
	
	   
		if (key == GLUT_KEY_UP   ) {
			//orbitDegreeX += 1.0f;
			spotDir[1] += 0.2f;
		}
		if (key == GLUT_KEY_DOWN ) {
			//orbitDegreeX -= 1.0f;
			spotDir[1] -= 0.2f;
		}
		
		
		if (key == GLUT_KEY_LEFT ) {
			//orbitDegreeZ -= 1.0f;
			spotDir[0] -= 0.2f;
		}
		if (key == GLUT_KEY_RIGHT) {
			//orbitDegreeZ += 1.0f;
			spotDir[0] += 0.2f;
		}
		
		
		if ( orbitDegreeX > 80.0f ) orbitDegreeX = 80.0f;
		if ( orbitDegreeX < -50.0f ) orbitDegreeX = -50.0f;
		
		if (orbitDegreeZ <= 360.0f) orbitDegreeZ -= 360.0f;
		if (orbitDegreeZ < 0.0f) orbitDegreeZ = 360.0f - orbitDegreeZ;
	
		glutPostRedisplay();

}

void Keyboard(unsigned char key, int x, int y) {
	
		printf("Billentyu lenyomva, kodja %c, pozicio (%d,%d). ", key, x, y);
	
		if (key == 'i') viewY += step;
		if (key == 'k') viewY -= step;
		if (key == 'j') viewX -= step;
		if (key == 'l') viewX += step;
		
		printf("\n");
		fflush (stdout);
		
		

		glutPostRedisplay();
}

int main(int argc, char* argv[])
{
  // >> Inicializalas

  camX = 0.0f;
  camY = -60.0f;
  camZ = 40.0f;
  
  viewX = 0.0f;
  viewY = 0.0f;
  viewZ = 0.0f;


  glutInit(&argc, argv);
  glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
  glutInitWindowSize(300, 300);
  glutCreateWindow("GLUT Alap");



  // << Inicializalas

  // >> Callback fuggvenyek

  glutReshapeFunc(ChangeSizeOrtho); // Parhuzamos vetites
  //glutReshapeFunc(ChangeSizePerspective); // Perspektiv vetites

  glutSpecialFunc(SpecialKeys);
  //glutKeyboardFunc(Keyboard);
  //glutKeyboardFunc(Keyboard);
  glutDisplayFunc(RenderScene);
  //glutTimerFunc(1000, Timer, 1); // 1 mp mulva meghivodik a Timer() fuggveny
  //glutIdleFunc(Idle); // Idle(), ha nem tortenik semmi
  
  // << Callback fuggvenyek

  SetupRC();
  glutMainLoop();
  
  return 0;
}