#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <time.h>

void initPositions(double *x, double *y, int N);
void initVelocity(double *xV, double *yV, int N);
void showTables(double *x, double *y, double *xV, double *yV, int N);
void display(double *x, double *y, int N);
void move(double *x, double *y, double *xV, double *yV, int N);
void collideWall(double *x, double *y, double *xV, double *yV, int N);

void main()
{
  int N = 10;
  double x[N], y[N], xV[N], yV[N];

  // OTWÓRZ OKNO GRAFICZNE O WYMIARACH 400x400

  initPositions(x, y, N);
  initVelocity(xV, yV, N);
  showTables(x, y, xV, yV, N);

  display(x, y, N);
  collideWall(x, y, xV, yV, N);

  for (int i = 0; i < 50; i++)
  {
    animate(100); // oczkiwanie przez 100 ms
    clear();      // czyszczenie okna dla nowej klatki
    move(x, y, xV, yV, N);
    collideWall(x, y, xV, yV, N);
    display(x, y, N);
  }
  printf("\n\n");
  showTables(x, y, xV, yV, N);
}

void initPositions(double *x, double *y, int N)
{
  srand(time(NULL));

  for (int i = 0; i < N; i++)
  {
    x[i] = rand() % 360 + 20;
    y[i] = rand() % 360 + 20;
  }
}

void initVelocity(double *xV, double *yV, int N)
{
  srand(time(NULL));

  for (int i = 0; i < N; i++)
  {
    xV[i] = (double)rand() / RAND_MAX * 2 - 1;
    yV[i] = (double)rand() / RAND_MAX * 2 - 1;
  }
}

void showTables(double *x, double *y, double *xV, double *yV, int N)
{
  printf("\tx\t\t\ty\t\t\txV\t\t\tyV\n");
  for (int i = 0; i < N; i++)
  {
    printf("%.2f\t%.2f\t%.2f\t%.2f\n", x[i], y[i], xV[i], yV[i]);
  }
}

void display(double *x, double *y, int N)
{
  for (int i = 0; i < N; i++)
  {
    // WYŚWIETLENIE PIŁKI O WSPÓŁRZĘDNYCH (x[i], y[i]) I PROMIENIU 20
  }
}

void move(double *x, double *y, double *xV, double *yV, int N)
{
  for (int i = 0; i < N; i++)
  {
    x[i] += xV[i];
    y[i] += yV[i];
  }
}
void collideWall(double *x, double *y, double *xV, double *yV, int N)
{
  for (int i = 0; i < N; i++)
  {
    if (x[i] - 20 <= 0 || x[i] + 20 >= 400)
      xV[i] *= -1;

    if (y[i] - 20 <= 0 || y[i] + 20 >= 400)
      yV[i] *= -1;
  }
}