#include <GLFW\glfw3.h>
#include <GLES2\gl2.h>
#include <iostream>

using std::cout;
using std::endl;

void printInfo(GLFWwindow *window) {
    const GLubyte *version = glGetString(GL_VERSION);
    const GLubyte *vendor = glGetString(GL_VENDOR);
    const GLubyte *renderer = glGetString(GL_RENDERER);
    const GLubyte *extensions = glGetString(GL_EXTENSIONS);
    cout << "Version: " << version << endl;
    cout << "Vendor: " << vendor << endl;
    cout << "Renderer: " << renderer << endl;
    cout << "Extensions: " << extensions << endl;

    int api   = glfwGetWindowAttrib(window, GLFW_CLIENT_API);
    int major = glfwGetWindowAttrib(window, GLFW_CONTEXT_VERSION_MAJOR);
    int minor = glfwGetWindowAttrib(window, GLFW_CONTEXT_VERSION_MINOR);
    int revision = glfwGetWindowAttrib(window, GLFW_CONTEXT_REVISION);

    if(api == GLFW_OPENGL_API) {
        cout << "OpenGL" << endl;
    }
    else if(api == GLFW_OPENGL_ES_API) {
        cout << "OpenGL ES" << endl;
    }

    cout << "Major version: " << major << endl;
    cout << "Minor version: " << minor << endl;
}

void errorHandler(int code, const char *description) {
    cout << "GLFW error reported." << endl;
    cout << "\tCode: " << code << endl;
    cout << "\tDescription: " << description << endl;
}

int main(void)
{
    GLFWwindow* window;

    /* Initialize the library */
    glfwSetErrorCallback(errorHandler);

    if (!glfwInit())
        return -1;

    /* Create a windowed mode window and its OpenGL context */
    glfwWindowHint(GLFW_CLIENT_API, GLFW_OPENGL_ES_API);

    window = glfwCreateWindow(640, 480, "Hello World", NULL, NULL);
    if (!window)
    {
        glfwTerminate();
        return -1;
    }

    /* Make the window's context current */
    glfwMakeContextCurrent(window);

    // Set up the shaders
    printInfo(window);
    GLuint handle = glCreateProgram();
    if(handle == 0) {
        cout << "Could not create a shader program handle." << endl;
    }

    /* Loop until the user closes the window */
    while (!glfwWindowShouldClose(window))
    {
        /* Render here */

        /* Swap front and back buffers */
        glfwSwapBuffers(window);

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

    glfwTerminate();
    return 0;
}