#include "gl.h"
#include "glfw3.h"
#include <stdio.h>
#include <stdbool.h>

GladGLContext* currentContext;

void processInput(GLFWwindow* window);
void FrameBufferSizeCallback(int x, int y, int height, int width);

int main()
{
    glfwInit();
    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 4);
    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 6);
    glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);

    GLFWwindow* window = glfwCreateWindow(
        800, 600, "Test Context", NULL, NULL
    );
    if (window == NULL)
    {
        printf("Fatal error: failed to create glfw window.");
        glfwTerminate();
        return -1;
    }
    else
    {
        printf("%llu\n", (uint64_t)window);
    }

    glfwMakeContextCurrent(window);

    currentContext = calloc(sizeof(GladGLContext));

    PFNGLCLEARCOLORPROC glClearColor = (PFNGLCLEARCOLORPROC)glfwGetProcAddress("glClearColor");
    PFNGLCLEARPROC glClear = (PFNGLCLEARPROC)glfwGetProcAddress("glClear");

    printf("%llu\n", (uint64_t)glClearColor);
    printf("%llu\n", (uint64_t)glClear);

    /*
    if (gladLoadGLContext(currentContext, (GLADloadfunc)glfwGetProcAddress))
    {
        printf("Fatal error: failed in loading OpenGL function.");
        glfwTerminate();
        return -1;
    }
    /**/

    glfwSetFramebufferSizeCallback(window, FrameBufferSizeCallback);

    while (!glfwWindowShouldClose(window))
    {
        processInput(window);

        glClearColor(0.9f, 0.3f, 0.9f, 1.0f);
        glClear(GL_COLOR_BUFFER_BIT /* | GLFW_DEPTH_BITS /**/);

        //printf("%llu", (uint64_t)currentContext->Clear);

        glfwSwapBuffers(window);
        glfwPollEvents();
    }
    glfwTerminate();
    return 0;
}

void processInput(GLFWwindow* window)
{
    if (glfwGetKey(window, GLFW_KEY_ESCAPE) == GLFW_PRESS)
        glfwSetWindowShouldClose(window, true);
}

void FrameBufferSizeCallback(int x, int y, int height, int width)
{
    currentContext->Viewport(0, 0, height, width);
}