#include <GL/glew.h>
#include <GLFW/glfw3.h>
#include <iostream>

#include "fbo.h"

FBO::FBO() : fbo_id_(-1), color_texture_id_(-1), position_texture_id_(-1), depth_rbo_id_(-1) {}

FBO::~FBO() {
    Cleanup();
}

void FBO::Init(int width, int height) {
    // Generate the framebuffer
    glGenFramebuffers(1, &fbo_id_);
    glBindFramebuffer(GL_FRAMEBUFFER, fbo_id_);

    // Generate the color texture
    glGenTextures(1, &color_texture_id_);
    glBindTexture(GL_TEXTURE_2D, color_texture_id_);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA32F, width, height, 0, GL_RGBA, GL_FLOAT, nullptr);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, color_texture_id_, 0);

    // Generate the position texture
    glGenTextures(1, &position_texture_id_);
    glBindTexture(GL_TEXTURE_2D, position_texture_id_);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA32F, width, height, 0, GL_RGBA, GL_FLOAT, nullptr);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT1, GL_TEXTURE_2D, position_texture_id_, 0);

    GLenum drawBuffers[2] = {GL_COLOR_ATTACHMENT0, GL_COLOR_ATTACHMENT1};
    glDrawBuffers(2, drawBuffers);

    // RBO was causing issues. Not using for now
    // Generate the Depth renderbuffer
    glGenRenderbuffers(1, &depth_rbo_id_);
    glBindRenderbuffer(GL_RENDERBUFFER, depth_rbo_id_);
    glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT, width, height);
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depth_rbo_id_);

    // Check if the framebuffer is complete
    if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
        std::cerr << "Error: Framebuffer is not complete!" << std::endl;
    }

    glBindFramebuffer(GL_FRAMEBUFFER, 0);
}

void FBO::Bind() {
    glBindFramebuffer(GL_FRAMEBUFFER, fbo_id_);
}

void FBO::Unbind() {
    glBindFramebuffer(GL_FRAMEBUFFER, 0);
}

void FBO::Cleanup() {
    if (color_texture_id_ != -1) {
        glDeleteTextures(1, &color_texture_id_);
    }
    if (depth_rbo_id_ != -1) {
        glDeleteTextures(1, &depth_rbo_id_);
    }
    if (fbo_id_ != -1) {
        glDeleteFramebuffers(1, &fbo_id_);
    }
}

GLuint FBO::GetColorTexture() const {
    return color_texture_id_;
}