#include <GL/glut.h>
#include <cmath>
#include <vector>

float angleX = 0.0f, angleY = 0.0f;
int lastX, lastY;
bool rotating = false;
GLuint texture;
const float radius = 0.3f;
const float cubeSize = 1.0f;

void loadTexture() {
    const int size = 64;
    unsigned char checkerTexture[size][size][3];
    for (int i = 0; i < size; ++i) {
        for (int j = 0; j < size; ++j) {
            int color = ((i / 8 + j / 8) % 2) * 255;
            checkerTexture[i][j][0] = checkerTexture[i][j][1] = checkerTexture[i][j][2] = color;
        }
    }
    glGenTextures(1, &texture);
    glBindTexture(GL_TEXTURE_2D, texture);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, size, size, 0, GL_RGB, GL_UNSIGNED_BYTE, checkerTexture);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
}

void drawSphere(float x, float y, float z) {
    glPushMatrix();
    glTranslatef(x, y, z);
    GLUquadric* quad = gluNewQuadric();
    gluQuadricTexture(quad, GL_TRUE);
    gluSphere(quad, radius, 32, 32);
    gluDeleteQuadric(quad);
    glPopMatrix();
}

void display() {
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glLoadIdentity();
    glTranslatef(0.0f, 0.0f, -3.0f);
    glRotatef(angleX, 1, 0, 0);
    glRotatef(angleY, 0, 1, 0);
    
    glEnable(GL_TEXTURE_2D);
    glBindTexture(GL_TEXTURE_2D, texture);
    
    std::vector<std::vector<float>> vertices = {
        {-cubeSize, -cubeSize, -cubeSize}, {cubeSize, -cubeSize, -cubeSize},
        {-cubeSize, cubeSize, -cubeSize}, {cubeSize, cubeSize, -cubeSize},
        {-cubeSize, -cubeSize, cubeSize}, {cubeSize, -cubeSize, cubeSize},
        {-cubeSize, cubeSize, cubeSize}, {cubeSize, cubeSize, cubeSize}
    };
    
    for (const auto& v : vertices) {
        drawSphere(v[0], v[1], v[2]);
    }
    
    glDisable(GL_TEXTURE_2D);
    glutSwapBuffers();
}

void reshape(int w, int h) {
    glViewport(0, 0, w, h);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(45, (float)w / h, 1, 10);
    glMatrixMode(GL_MODELVIEW);
}

void mouse(int button, int state, int x, int y) {
    if (button == GLUT_LEFT_BUTTON) {
        rotating = (state == GLUT_DOWN);
        lastX = x;
        lastY = y;
    }
}

void motion(int x, int y) {
    if (rotating) {
        angleX += (y - lastY);
        angleY += (x - lastX);
        lastX = x;
        lastY = y;
        glutPostRedisplay();
    }
}

void initGL() {
    glEnable(GL_DEPTH_TEST);
    glEnable(GL_LIGHTING);
    glEnable(GL_LIGHT0);
    glEnable(GL_COLOR_MATERIAL);
    glEnable(GL_TEXTURE_2D);
    loadTexture();
}

int main(int argc, char** argv) {
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
    glutInitWindowSize(600, 600);
    glutCreateWindow("Esferas en un cubo");
    glutDisplayFunc(display);
    glutReshapeFunc(reshape);
    glutMouseFunc(mouse);
    glutMotionFunc(motion);
    initGL();
    glutMainLoop();
    return 0;
}