#include <glad/glad.h>
#include <iostream>
#include "Graphics.h"
#include "Shader.h"

Graphics::Graphics() : window(nullptr), VAO(0), VBO(0) {}

Graphics::~Graphics()
{
    Shutdown();
}

void Graphics::Initialize(GLFWwindow* window)
{
    this->window = window;

    if (!gladLoadGLLoader((GLADloadproc)glfwGetProcAddress)) {
        std::cerr << "Failed to initialize GLAD" << std::endl;
        return;
    }

    LoadShaders();
    SetupBuffers();
}

void Graphics::LoadShaders()
{
    shader = Shader(RESOURCES_PATH"shaders/shader.vs", RESOURCES_PATH"shaders/shader.fs");
}

void Graphics::SetupBuffers()
{
    float vertices[] = {
         0.5f, -0.5f, 0.0f, 1.0f, 0.0f, 0.0f,
        -0.5f, -0.5f, 0.0f, 0.0f, 1.0f, 0.0f,
         0.0f,  0.5f, 0.0f, 0.0f, 0.0f, 1.0f
    };

    glGenVertexArrays(1, &VAO);
    glGenBuffers(1, &VBO);

    glBindVertexArray(VAO);

    glBindBuffer(GL_ARRAY_BUFFER, VBO);
    glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);

    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void*)0);
    glEnableVertexAttribArray(0);

    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void*)(3 * sizeof(float)));
    glEnableVertexAttribArray(1);

    glBindBuffer(GL_ARRAY_BUFFER, 0);
    glBindVertexArray(0);
}

void Graphics::FramebufferSizeCallback(GLFWwindow* window, int width, int height)
{
    glViewport(0, 0, width, height);
}

void Graphics::Render() {
    glClear(GL_COLOR_BUFFER_BIT);

    shader.Use();
    glBindVertexArray(VAO);
    glDrawArrays(GL_TRIANGLES, 0, 3);
}

void Graphics::Shutdown()
{
    glDeleteVertexArrays(1, &VAO);
    glDeleteBuffers(1, &VBO);
}