#include <GL/glew.h>
#include <GLFW/glfw3.h>
#include <cmath>
#include <vector>
#include <iostream>

const int windowWidth = 800;
const int windowHeight = 600;

struct Ball {
    float x, y, z;
    float vx, vy, vz;
    float r, g, b;
};

// Ustawienia rzutu ukośnego dla każdej kuli (kąt startowy, prędkość początkowa)
std::vector<Ball> balls;

void initializeBalls() {
    for (int i = 0; i < 10; ++i) {
        float angle = 15 + i * 6; // Kąty między 15 a 75 stopni
        float speed = 10 + i; // Prędkości początkowe
        Ball ball = {0, 0, 0, speed * cos(angle * M_PI / 180.0f), speed * sin(angle * M_PI / 180.0f), 0, (float)rand()/RAND_MAX, (float)rand()/RAND_MAX, (float)rand()/RAND_MAX};
        balls.push_back(ball);
    }
}

// Funkcja do integracji Rungego-Kutty
void rungeKuttaStep(Ball &ball, float dt) {
    float k1vx = -0.1f * ball.vx;
    float k1vy = -9.8f - 0.1f * ball.vy;
    float k2vx = -0.1f * (ball.vx + 0.5f * dt * k1vx);
    float k2vy = -9.8f - 0.1f * (ball.vy + 0.5f * dt * k1vy);
    float k3vx = -0.1f * (ball.vx + 0.5f * dt * k2vx);
    float k3vy = -9.8f - 0.1f * (ball.vy + 0.5f * dt * k2vy);
    float k4vx = -0.1f * (ball.vx + dt * k3vx);
    float k4vy = -9.8f - 0.1f * (ball.vy + dt * k3vy);

    ball.vx += (dt / 6.0f) * (k1vx + 2.0f * k2vx + 2.0f * k3vx + k4vx);
    ball.vy += (dt / 6.0f) * (k1vy + 2.0f * k2vy + 2.0f * k3vy + k4vy);
    ball.x += ball.vx * dt;
    ball.y += ball.vy * dt;
}

void display() {
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glLoadIdentity();
    gluLookAt(0, 5, 20, 0, 0, 0, 0, 1, 0);

    for (const auto &ball : balls) {
        glPushMatrix();
        glTranslatef(ball.x, ball.y, ball.z);
        glColor3f(ball.r, ball.g, ball.b);
        glutSolidSphere(0.5, 20, 20);
        glPopMatrix();
    }
}

void update() {
    float dt = 0.01f;
    for (auto &ball : balls) {
        rungeKuttaStep(ball, dt);
    }
}

void setupOpenGL() {
    glEnable(GL_DEPTH_TEST);
    glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
}

int main() {
    if (!glfwInit()) {
        std::cerr << "Failed to initialize GLFW" << std::endl;
        return -1;
    }

    GLFWwindow* window = glfwCreateWindow(windowWidth, windowHeight, "Animacja 10 kul - Rzut ukośny", nullptr, nullptr);
    if (!window) {
        std::cerr << "Failed to create GLFW window" << std::endl;
        glfwTerminate();
        return -1;
    }

    glfwMakeContextCurrent(window);
    glewExperimental = GL_TRUE;
    if (glewInit() != GLEW_OK) {
        std::cerr << "Failed to initialize GLEW" << std::endl;
        return -1;
    }

    initializeBalls();
    setupOpenGL();

    while (!glfwWindowShouldClose(window)) {
        display();
        update();
        glfwSwapBuffers(window);
        glfwPollEvents();
    }

    glfwDestroyWindow(window);
    glfwTerminate();
    return 0;
}