// A simple multi-window example using GLFW
// This code is based on https://github.com/glfw/glfw/blob/master/examples/windows.c

#include <GLFW/glfw3.h>

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

// A function to handle window resizing
void window_size_callback(GLFWwindow* window, int width, int height)
{
    glViewport(0, 0, width, height);
}

// A function to handle window closing
void window_close_callback(GLFWwindow* window)
{
    printf("Window %p closed\n", window);
}

// A function to handle key input
void key_callback(GLFWwindow* window, int key, int scancode, int action, int mods)
{
    if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS)
        glfwSetWindowShouldClose(window, GLFW_TRUE);
}

int main(void)
{
    // Initialize GLFW
    if (!glfwInit())
    {
        printf("Failed to initialize GLFW\n");
        exit(EXIT_FAILURE);
    }

    // Create two windows with OpenGL contexts
    GLFWwindow* window1 = glfwCreateWindow(640, 480, "Window 1", NULL, NULL);
    if (!window1)
    {
        printf("Failed to create window 1\n");
        glfwTerminate();
        exit(EXIT_FAILURE);
    }

    GLFWwindow* window2 = glfwCreateWindow(640, 480, "Window 2", NULL, NULL);
    if (!window2)
    {
        printf("Failed to create window 2\n");
        glfwDestroyWindow(window1);
        glfwTerminate();
        exit(EXIT_FAILURE);
    }

    // Set the callbacks for each window
    glfwSetWindowSizeCallback(window1, window_size_callback);
    glfwSetWindowCloseCallback(window1, window_close_callback);
    glfwSetKeyCallback(window1, key_callback);

    glfwSetWindowSizeCallback(window2, window_size_callback);
    glfwSetWindowCloseCallback(window2, window_close_callback);
    glfwSetKeyCallback(window2, key_callback);

    // Set the clear colors for each window
    const struct { float r, g, b; } colors[] =
    {
        { 0.95f, 0.32f, 0.11f },
        { 0.50f, 0.80f, 0.16f }
    };

    // Loop until both windows are closed
    while (!glfwWindowShouldClose(window1) && !glfwWindowShouldClose(window2))
    {
        // Clear and swap buffers for each window
        for (int i = 0; i < 2; i++)
        {
            GLFWwindow* window = (i == 0) ? window1 : window2;
            glfwMakeContextCurrent(window);
            glClearColor(colors[i].r, colors[i].g, colors[i].b, 1.f);
            glClear(GL_COLOR_BUFFER_BIT);
            glfwSwapBuffers(window);
        }

        // Poll for and process events
        glfwPollEvents();
    }

    // Destroy the windows and terminate GLFW
    glfwDestroyWindow(window1);
    glfwDestroyWindow(window2);

    glfwTerminate();
}