#include "glew.h"
#include <GL/gl.h>
#include <GL/glext.h>
#include <cstdio>
#include "sparrowrenderer.h"

#include "camera.h"
#include "framebuffer.h"
#include "module.h"
#include <chrono>
#include <string.h>
#include <iostream>
#include "pipeline.h"
#include "scene.h"
// main methods

bool SparrowRenderer::modernOpenglAvailable = false;

void SparrowRenderer::initGL(int w, int h, bool forceCrappy)
{
    glewExperimental = GL_TRUE;
    GLenum err = glewInit();
    if (GLEW_OK != err)
        fprintf(stderr, "Warning: glewInit failed!\n");
    if (!forceCrappy &&
        GLEW_ARB_vertex_program   &&
        GLEW_ARB_draw_buffers     &&
        GLEW_ARB_framebuffer_object &&
        glewIsSupported("GL_VERSION_3_3") &&
        GLEW_VERSION_3_3 &&
        strcmp("3.30",(const char *)glGetString(GL_SHADING_LANGUAGE_VERSION)) <= 0)
    {
        modernOpenglAvailable = true;
        printf("Modern OpenGL available.\n");
    }
    else
    {
        modernOpenglAvailable = false;
        fprintf(stderr, "Warning: modern OpenGL not supported!\nEnabling fallback crappy rendering mode\n");
    }

    std::cout << "OpenGL " << glGetString(GL_VERSION) << std::endl;
    std::cout << "GLSL " << glGetString(GL_SHADING_LANGUAGE_VERSION) << std::endl;
    std::cout << "Renderer " << glGetString(GL_RENDERER) << std::endl;
    std::cout << "Vendor " << glGetString(GL_VENDOR) << std::endl;

    resizeGL(w, h);
}

void SparrowRenderer::resizeGL(int w, int h)
{
    width = w;
    height = h;
    if(m_scene != NULL)
    {
        if(m_scene->getPipeline() != NULL)
            m_scene->getPipeline()->resizeGL(w, h);
    }
}

void SparrowRenderer::renderGL()
{
    if(m_scene != NULL && m_scene->getPipeline() != NULL)
    {
        m_scene->getPipeline()->renderGL(m_scene);
    }
    glFinish();
}

bool SparrowRenderer::isModernOpenGLAvailable()
{
    return modernOpenglAvailable;
}

// scene methods

void SparrowRenderer::setScene(Scene* myScene)
{
    m_scene = myScene;
    if(m_scene == NULL || m_scene->getPipeline() == NULL)
        fprintf(stderr, "WARNING : incomplete scene class, rendering may not work properly.\n");
}