//_---------------------------------------------------------------------------

#include <SDL/SDL.h>
#include <stdlib.h>
#include <stdio.h>



//-- Globalne promenljive -----
// Parametri ekrana, fps, povrsina za pozadinu i event handler

const int S_WIDTH= 640;
const int S_HEIGHT= 480;
const int S_BPP= 32;

const int FRAMES_PER_SECOND= 30;

SDL_Surface *screen= NULL;

SDL_Event event;

//-- Klasa osnovne kocke

class KOCKA {
  
  private:
  //Atributi
  SDL_Rect box;
  int Vx, Vy;
  int pokretna;
  
  public:
  
  KOCKA();
  KOCKA(int a, int b, int c, int d);
  
  void set_x(int i) { box.x= i; }
  void set_y(int i) {box.y= i; }
  int get_x() { return box.x; }
  int get_y() { return box.y; }
  int get_w() { return box.w; }
  int get_h() { return box.h; }
  void set_xy(int a, int b) { box.x= a; box.y= b; }
  void set_vel(int a, int b) { Vx= a; Vy= b; }
  void set_Vx(int a) { Vx= a; }
  void set_Vy(int a) { Vy= a; }
  void flip_Vx() { Vx= -Vx; }
  void flip_Vy() { Vy= -Vy; }
 
  void mov_x() { box.x+= Vx; }
  void mov_y() { box.y+= Vy; }
  void pomeri_x();
  void pomeri_y();
  void pokreni() { pokretna= 1; }
  SDL_Rect get_box() { return box; }
  void prikazi();
  void BsudarX(KOCKA *a);
  void BsudarY(KOCKA *a);

};

//== Klasa Player KOCKA koja je prosirena osnovna KOCKA
class PKOCKA: public KOCKA { 
  
  public:

	  PKOCKA (int a, int b, int c, int d): KOCKA(a,b,c,d) { set_vel(0,0); }
  int Csudar(KOCKA *a);
  void handle_input();
  void prikazi();

};

 class Timer
{
    private:
    //The clock time when the timer started
    int startTicks;

    //The ticks stored when the timer was paused
    int pausedTicks;

    //The timer status
    int paused;
    int started;

    public:
    //Initializes variables
    Timer();

    //The various clock actions
    void start();
    void stop();
    void pause();
    void unpause();
    
    //Get the number of ticks since the timer started
    //or gets the number of ticks when the timer was paused
    int get_ticks();

    //Checks the status of the timer
    int is_started();
    int is_paused();
};
// Podrazumevani konstruktor
KOCKA::KOCKA(){
  box.x= 0;
  box.y= 0;
  box.w= 20;
  box.h= 20;
  Vx= Vy= 0;
  pokretna= 0;
}
// Konstruktor
KOCKA::KOCKA(int a, int b, int c, int d) {
  box.x= a;
  box.y= b;
  box.w= c;
  box.h= d;
  for (int j= 0; j<10; j++) { int g= rand(); }
  Vx= (int)(((double)rand())/((double)RAND_MAX + (double)1)*10);
  Vy= 10 - Vx;
  pokretna= 0;
}

// -- Pomeranje kocki po ekranu po x osi
void KOCKA::pomeri_x() {

  if (!pokretna) return;

  box.x+= Vx;

  int left= box.x;
  int right= box.x + box.w;
  if (left<0) {
    box.x= 0;
    Vx= -Vx;
  }
  if (right>S_WIDTH) {
    box.x= S_WIDTH - box.w;
    Vx= -Vx;
  }

}

void KOCKA::pomeri_y() {

	if (!pokretna) return;

	box.y+= Vy;

	int upper= box.y;
    int down= box.y + box.h;
	if (upper<0) {
		box.y= 0;
		Vy= -Vy;
	}
	if (down>S_HEIGHT) {
		box.y= S_HEIGHT - box.h;
		Vy= -Vy;
	}
}

//-- Iscrtavanje na ekran
void KOCKA::prikazi() {
   
  if (SDL_FillRect(screen, &box, SDL_MapRGB(screen->format,0,0,0xFF))==-1) {
    printf("Greska u iscrtavanju kocke :  %s\n", SDL_GetError());
    exit(1);
  }

}

//-- Regulisanje sudara kocke sa drugom kockom
void KOCKA::BsudarX(KOCKA *A) {
  int left= box.x;
  int right= box.x + box.w;
  int upper= box.y;
  int down= box.y + box.h;
  int leftA= A->get_x();
  int rightA= A->get_x() + A->get_w();
  int upperA= A->get_y();
  int downA= A->get_y() + A->get_h();

  if (left>=rightA) return;
  else if (right<=leftA) return;
       else if (down<=upperA) return;
            else if (upper>=downA) return;
			else { 
				if ((rightA-left)<11) set_x(rightA);
				if ((right-leftA)<11) set_x(leftA-box.w);
				flip_Vx(); 
				A->flip_Vx(); 
			}
  return;
}

void KOCKA::BsudarY(KOCKA *A) {

int left= box.x;
  int right= box.x + box.w;
  int upper= box.y;
  int down= box.y + box.h;
  int leftA= A->get_x();
  int rightA= A->get_x() + A->get_w();
  int upperA= A->get_y();
  int downA= A->get_y() + A->get_h();

  if (left>=rightA) return;
  else if (right<=leftA) return;
       else if (down<=upperA) return;
            else if (upper>=downA) return;
			else { 
				if ((down-upperA)<11) set_y(upperA-box.h);
				if ((downA-upper)<11) set_y(downA);
				flip_Vy(); 
				A->flip_Vy(); 
			}
  return;
}

// Sudar player kocke sa CPU kockom
int PKOCKA::Csudar(KOCKA *A) {
  int left= get_x();
  int right= get_x() + get_w();
  int upper= get_y();
  int down= get_y() + get_h();
  int leftA= A->get_x();
  int rightA= A->get_x() + A->get_w();
  int upperA= A->get_y();
  int downA= A->get_y() + A->get_h();


  if (left>rightA) return 0;
  else if (right<leftA) return 0;
       else if (down<upperA) return 0;
            else if (upper>downA) return 0;
                 else return 1;
}

//-- Pomeranje player kocke kursorima na tastaturi
void PKOCKA::handle_input() {
      //If a key was pressed
    if( event.type == SDL_KEYDOWN )
    {
        //Adjust the velocity
        switch( event.key.keysym.sym )
        {
            case SDLK_UP: set_Vy(-10); break;
            case SDLK_DOWN: set_Vy(10); break;
            case SDLK_LEFT: set_Vx(-10); break;
            case SDLK_RIGHT: set_Vx(10); break;
        }
    }
    //If a key was released
    else if( event.type == SDL_KEYUP )
    {
        //Adjust the velocity
        switch( event.key.keysym.sym )
        {
            case SDLK_UP: set_Vy(0); break;
            case SDLK_DOWN: set_Vy(0); break;
            case SDLK_LEFT: set_Vx(0); break;
            case SDLK_RIGHT: set_Vx(0); break;
        }        
    }
		
	mov_x();
	mov_y();

	int left= get_x();
	int right= get_x() + get_w();
	int upper= get_y();
	int down= get_y() + get_h();
	if (left<0) set_x(0);
	if (right>S_WIDTH) set_x( S_WIDTH - get_w());	
	if (upper<0) set_y(0);
	if (down>S_HEIGHT) set_y( S_HEIGHT - get_h());

}

void PKOCKA::prikazi() {
	   
  if (SDL_FillRect(screen, &(get_box()), SDL_MapRGB(screen->format,0xFF,0,0))==-1) {
    printf("Greska u iscrtavanju kocke :  %s\n", SDL_GetError());
    exit(1);
  }
}

Timer::Timer()
{
    //Initialize the variables
    startTicks = 0;
    pausedTicks = 0;
    paused = 0;
    started = 0;
}

void Timer::start()
{
    //Start the timer
    started = 1;
    
    //Unpause the timer
    paused = 0;
    
    //Get the current clock time
    startTicks = SDL_GetTicks();
}

void Timer::stop()
{
    //Stop the timer
    started = 0;

    //Unpause the timer
    paused = 0;
}

void Timer::pause()
{
    //If the timer is running and isn't already paused
    if( (started) && (!paused) )
    {
        //Pause the timer
        paused = 1;

        //Calculate the paused ticks
        pausedTicks = SDL_GetTicks() - startTicks;
    }
}

void Timer::unpause()
{
    //If the timer is paused
    if(paused)
    {
        //Unpause the timer
        paused = 0;
    
        //Reset the starting ticks
        startTicks = SDL_GetTicks() - pausedTicks;
        
        //Reset the paused ticks
        pausedTicks = 0;
    }
}

int Timer::get_ticks()
{
    //If the timer is running
    if(started)
    {
        //If the timer is paused
        if(paused)
        {
            //Return the number of ticks when the the timer was paused
            return pausedTicks;
        }
        else
        {
            //Return the current time minus the start time
            return SDL_GetTicks() - startTicks;
        }    
    }
    
    //If the timer isn't running
    return 0;    
}

int Timer::is_started()
{
    return started;
}

int Timer::is_paused()
{
    return paused;
}

//-- GLAVNI PROGRAM ---
int main( int argc, char* args[] ) {
  
  //Neki flagovi
  int quit= 0;
  int run= 0;
  int end= 0;
  
  Timer tim;
  //Predmeti na ekranu
  KOCKA* K1= new KOCKA(200,300,50,50);
  KOCKA* K2= new KOCKA(400,300,50,50);
  PKOCKA* PK= new PKOCKA(310,0,50,50);
  PK->set_vel(0,0);
  K1->set_vel(5,-5);
 // K2->set_vel(1,-1);
  K1->pokreni();
  K2->pokreni();

  //-- Inicijalizacija SDL-a
  if (SDL_Init(SDL_INIT_EVERYTHING) == -1) 
  {
    printf("Greska u inicijalz. svega  :  %s\n", SDL_GetError());
    exit(2);
  }
  // Inicijalizacija ekrana
  //screen= SDL_SetVideoMode(S_WIDTH, S_HEIGHT, S_BPP, SDL_HWSURFACE|SDL_DOUBLEBUF);
  screen= SDL_SetVideoMode(S_WIDTH, S_HEIGHT, S_BPP, SDL_SWSURFACE);
  if (screen== NULL)
  {
    printf("Greska u inicijaliz. ekrana :  %s\n", SDL_GetError());
    exit(3);
  }
  // Naslov na prozoru
  SDL_WM_SetCaption("--- POS ProjecT ---       Press SPACE to start!", NULL);

  SDL_ShowCursor(SDL_DISABLE);

  // Radni deo --------

  while (!quit) {

    //start the frame timer
    tim.start();

    while (SDL_PollEvent(&event)) {



      if (event.type == SDL_QUIT) quit= 1;

      if ( event.type == SDL_KEYDOWN )
      {
        if ( event.key.keysym.sym == SDLK_ESCAPE ) { quit = 1; SDL_WM_SetCaption("--- POS ProjecT ---", NULL); }
        if ( event.key.keysym.sym == SDLK_SPACE ) { run = 1; }
      }
    }
    
    // Handles input and moves squares
    if ((run)&&(!end)) {
       PK->handle_input();
	   
       K1->pomeri_x();
	   K1->BsudarX(K2);
	   K1->pomeri_y();
	   K1->BsudarY(K2);
	   K2->pomeri_x();
	   K2->BsudarX(K1);
	   K2->pomeri_y();
	   K2->BsudarY(K1);
	   
	   if ((PK->Csudar(K1))||(PK->Csudar(K2))) { 
		end= 1;
		SDL_WM_SetCaption("--- POS ProjecT ---      GAME OVER  (press esc to quit)", NULL);
	   }
    }
    // Iscrtavanje po ekranu
	SDL_FillRect( screen, &screen->clip_rect, SDL_MapRGB( screen->format,0xFF,0xFF,0xFF)); 
    PK->prikazi();
    K1->prikazi();
    K2->prikazi();

	//Flipovanje ekrana
	if(SDL_Flip(screen) == -1) {
		printf("Greska u flipovanju ekrana :  %s\n", SDL_GetError());
		exit(3);
    }
        
    //Cap the frame rate
    while( tim.get_ticks() < 1000 / FRAMES_PER_SECOND )
    {
            //wait  
		SDL_Delay( 1000/FRAMES_PER_SECOND - tim.get_ticks() );
	}

  }

  // Ciscenje programa
  delete K1;
  delete K2;
  delete PK;

  printf("Program se uspesno zavrsio");

  SDL_Quit();

  return 0;

}