#include <stdio.h>
#include <GLFW/glfw3.h>

int main (int argc, char** argv)
{
    GLFWwindow* window;

    if (!glfwInit()) {
        fprintf(stderr, "could not init glfw.\n");
        return 1;

    }
    window = glfwCreateWindow(640, 480, "Hello Window", NULL, NULL);
    if (!window) {
        fprintf(stderr, "could not initialize glfw window\n");
        return 1;
    }
    
    glfwMakeContextCurrent(window);

    
    unsigned char* data = new unsigned char [100 * 100 * 3];
    for (int y=0; y < 100; y++) {
        for (int x = 0; x < 100; x++) {
            data[y * 100 * 3 + x * 3] = 0xff;
            data[y * 100 * 3 + x * 3 + 1] = 0x00;
            data[y * 100 * 3 + x * 3 + 2] = 0x00;
        }
    }

    GLuint texture_handle;
    glGenTextures(1, &texture_handle);
    glBindTexture(GL_TEXTURE_2D, texture_handle);
    glTexImage2D(texture_handle, 0, GL_RGB, 100, 100, 0, GL_RGB, GL_UNSIGNED_BYTE, data);

    
    while (!glfwWindowShouldClose(window)) {

        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        glDrawPixels(100, 100, GL_RGB, GL_UNSIGNED_BYTE, data);

        int window_width, window_height;
        glfwGetFramebufferSize(window, &window_width, &window_height);
        glMatrixMode(GL_PROJECTION);

        glLoadIdentity();
        glOrtho(0, window_width, 0, window_height, -1, 1);

        glMatrixMode(GL_MODELVIEW);

        glEnable(GL_TEXTURE_2D);
        glBindTexture(GL_TEXTURE_2D, texture_handle);
        glBegin(GL_QUADS);
            glTexCoord2d(0,0);glTexCoord2d(0,0);
            glTexCoord2d(1,0);glTexCoord2d(100,0);
            glTexCoord2d(1,1);glTexCoord2d(100,100);
            glTexCoord2d(0,1);glTexCoord2d(0,100);
        glEnd();
        glDisable(GL_TEXTURE_2D);

        glfwSwapBuffers(window);
        glfwWaitEvents();

    }

    return 0;

}