#include "engine.h"

#include <SFML/System/Clock.hpp>
#include <SFML/Window.hpp>
#include <input.h>
#include <sparrowrenderer.h>
#include <btBulletCollisionCommon.h>
#include <btBulletDynamicsCommon.h>
#include "resourcemanager.h"
#include "scene.h"

Engine::Engine() :
    m_input(NULL),
    m_window(NULL)
{
    m_clock = new sf::Clock();
    m_clock->restart();
    m_renderer = new SparrowRenderer();
    m_renderer->setCamera(NULL); // TODO
}

void Engine::createWindow(std::string title,
                unsigned int w,
                unsigned int h,
                bool isWindowed)
{
    m_window = new sf::Window(sf::VideoMode(w, h),
                              title,
                              isWindowed ? sf::Style::Default : sf::Style::Fullscreen,
                              sf::ContextSettings(24));
    m_window->setFramerateLimit(60);
    m_input = new Input(m_window);
    m_renderer->initGL(w, h);
}

void Engine::initPhysics()
{
    btDefaultCollisionConfiguration *collisionConfiguration = new btDefaultCollisionConfiguration();
    btBroadphaseInterface *broadPhase = new btAxisSweep3(btVector3(-1000, -1000, -1000), btVector3(1000, 1000, 1000));
    btCollisionDispatcher *dispatcher = new btCollisionDispatcher(collisionConfiguration);
    btSequentialImpulseConstraintSolver *solver = new btSequentialImpulseConstraintSolver();
    m_world = new btDiscreteDynamicsWorld(dispatcher, broadPhase, solver, collisionConfiguration);
    m_world->setGravity(btVector3(0, -10, 0));
}

void Engine::update()
{
    // update delta time
    m_lastTimeStamp = m_timeStamp;
    m_timeStamp = (unsigned int) m_clock->getElapsedTime().asMilliseconds();
    // update Events
    m_input->updateEvents();
    // update Scene
    m_scene->update();
    // update Physics
    m_world->stepSimulation(1000.f*(float)getDeltaTime());
    // update Display
    m_renderer->renderGL();
    m_window->display();
}

void Engine::start()
{
    running = true;
    while(!m_input->isCloseRequested() && running){
        update();
    }
}

void Engine::stop()
{
    running = false;
}

unsigned int Engine::getTime()
{
    return m_timeStamp;
}

unsigned int Engine::getDeltaTime()
{
    return m_timeStamp - m_lastTimeStamp;
}

void Engine::setScene(std::string sceneName)
{
    m_scene = RESOURCE_GET(Scene,sceneName);
}