/*
 *   ORXONOX - the hottest 3D action shooter ever to exist
 *                    > www.orxonox.net <
 *
 *
 *   License notice:
 *
 *   This program is free software; you can redistribute it and/or
 *   modify it under the terms of the GNU General Public License
 *   as published by the Free Software Foundation; either version 2
 *   of the License, or (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 *   Author:
 *      Reto Grieder
 *   Co-authors:
 *      Benjamin Knecht <beni_at_orxonox.net>, (C) 2007, Felix Schulthess
 *
 */

 /**
    @file orxonox.cc
    @brief Orxonox class
  */

#include "OrxonoxStableHeaders.h"
#include "GraphicsEngine.h"

#include <fstream>

#include <OgreConfigFile.h>
#include <OgreException.h>
#include <OgreLogManager.h>
#include <OgreRoot.h>
#include <OgreSceneManager.h>
#include <OgreTextureManager.h>
#include <OgreViewport.h>

#include "core/CoreIncludes.h"
#include "core/ConfigValueIncludes.h"
#include "core/Debug.h"
#include "core/CommandExecutor.h"
#include "core/ConsoleCommand.h"

#include "overlays/console/InGameConsole.h"
#include "overlays/OverlayGroup.h"
#include "tools/ParticleInterface.h"
#include "Settings.h"
#include "tools/WindowEventListener.h"


namespace orxonox
{
  /**
    @brief Returns the singleton instance and creates it the first time.
    @return The only instance of GraphicsEngine.
  */
  /*static*/ GraphicsEngine& GraphicsEngine::getSingleton()
  {
    static GraphicsEngine theOnlyInstance;
    return theOnlyInstance;
  }

  /**
    @brief Only use constructor to initialise variables and pointers!
  */
  GraphicsEngine::GraphicsEngine() :
    root_(0),
    scene_(0),
    renderWindow_(0)
  {
    RegisterObject(GraphicsEngine);

    this->detailLevelParticle_ = 0;

    this->setConfigValues();
    CCOUT(4) << "Constructed" << std::endl;
  }

  void GraphicsEngine::setConfigValues()
  {
    SetConfigValue(resourceFile_,    "resources.cfg").description("Location of the resources file in the data path.");
    SetConfigValue(ogreConfigFile_,  "ogre.cfg").description("Location of the Ogre config file");
    SetConfigValue(ogrePluginsFile_, "plugins.cfg").description("Location of the Ogre plugins file");
    SetConfigValue(ogreLogFile_,     "ogre.log").description("Logfile for messages from Ogre. \
                                                             Use \"\" to suppress log file creation.");
    SetConfigValue(ogreLogLevelTrivial_ , 5).description("Corresponding orxonox debug level for ogre Trivial");
    SetConfigValue(ogreLogLevelNormal_  , 4).description("Corresponding orxonox debug level for ogre Normal");
    SetConfigValue(ogreLogLevelCritical_, 2).description("Corresponding orxonox debug level for ogre Critical");

    unsigned int old = this->detailLevelParticle_;
    SetConfigValue(detailLevelParticle_, 2).description("O: off, 1: low, 2: normal, 3: high");

    if (this->detailLevelParticle_ != old)
      for (Iterator<ParticleInterface> it = ObjectList<ParticleInterface>::begin(); it; ++it)
        it->detailLevelChanged(this->detailLevelParticle_);
  }

  /**
    @brief Called after main() --> call destroyObjects()!
  */
  GraphicsEngine::~GraphicsEngine()
  {
    this->destroy();
  }

  /**
    @brief Destroys all the internal objects. Call this method when you
           normally would call the destructor.
  */
  void GraphicsEngine::destroy()
  {
    CCOUT(4) << "Destroying objects..." << std::endl;
    Ogre::WindowEventUtilities::removeWindowEventListener(this->renderWindow_, this);
    if (this->root_)
      delete this->root_;
    this->root_ = 0;
    this->scene_ = 0;
    this->renderWindow_ = 0;
    // delete the ogre log and the logManager (since we have created it).
    if (Ogre::LogManager::getSingletonPtr() != 0)
    {
      Ogre::LogManager::getSingleton().getDefaultLog()->removeListener(this);
      Ogre::LogManager::getSingleton().destroyLog(Ogre::LogManager::getSingleton().getDefaultLog());
      delete Ogre::LogManager::getSingletonPtr();
    }
    CCOUT(4) << "Destroying objects done" << std::endl;
  }

  /**
    @brief Creates the Ogre Root object and sets up the ogre log.
  */
  bool GraphicsEngine::setup()
  {
    CCOUT(3) << "Setting up..." << std::endl;
    // temporary overwrite of dataPath, change ini file for permanent change

// TODO: LogManager doesn't work on specific systems. The why is unknown yet.
#if ORXONOX_PLATFORM == ORXONOX_PLATFORM_WIN32
    // create a logManager
    // note: If there's already a logManager, Ogre will complain by a failed assertation.
    // but that shouldn't happen, since this is the first time to create a logManager..
    Ogre::LogManager* logger = new Ogre::LogManager();
    CCOUT(4) << "Ogre LogManager created" << std::endl;

    // create our own log that we can listen to
    Ogre::Log *myLog;
    if (this->ogreLogFile_ == "")
      myLog = logger->createLog("ogre.log", true, false, true);
    else
      myLog = logger->createLog(this->ogreLogFile_, true, false, false);
    CCOUT(4) << "Ogre Log created" << std::endl;

    myLog->setLogDetail(Ogre::LL_BOREME);
    myLog->addListener(this);
#endif

    // Root will detect that we've already created a Log
    CCOUT(4) << "Creating Ogre Root..." << std::endl;

    if (ogrePluginsFile_ == "")
    {
      COUT(1) << "Error: Ogre plugins file set to \"\". Cannot load." << std::endl;
      return false;
    }
    if (ogreConfigFile_ == "")
    {
      COUT(1) << "Error: Ogre config file set to \"\". Cannot load." << std::endl;
      return false;
    }
    if (ogreLogFile_ == "")
    {
      COUT(1) << "Error: Ogre log file set to \"\". Cannot load." << std::endl;
      return false;
    }

    try
    {
      root_ = new Ogre::Root(ogrePluginsFile_, ogreConfigFile_, ogreLogFile_);
    }
    catch (Ogre::Exception ex)
    {
      COUT(2) << "Error: There was an exception when creating Ogre Root." << std::endl;
      return false;
    }

    if (!root_->getInstalledPlugins().size())
    {
      COUT(1) << "Error: No plugins declared. Cannot load Ogre." << std::endl;
      COUT(0) << "Is the plugins file correctly declared?" << std::endl;
      return false;
    }

#if 0
    // tame the ogre ouput so we don't get all the mess in the console
    Ogre::Log* defaultLog = Ogre::LogManager::getSingleton().getDefaultLog();
    defaultLog->setDebugOutputEnabled(false);
    defaultLog->setLogDetail(Ogre::LL_BOREME);
    defaultLog->addListener(this);
#endif

    CCOUT(4) << "Creating Ogre Root done" << std::endl;

    // specify where Ogre has to look for resources. This call doesn't parse anything yet!
    if (!declareRessourceLocations())
      return false;

    CCOUT(3) << "Set up done." << std::endl;
    return true;
  }

  bool GraphicsEngine::declareRessourceLocations()
  {
    CCOUT(4) << "Declaring Resources" << std::endl;
    //TODO: Specify layout of data file and maybe use xml-loader
    //TODO: Work with ressource groups (should be generated by a special loader)

    if (resourceFile_ == "")
    {
      COUT(1) << "Error: Resource file set to \"\". Cannot load." << std::endl;
      return false;
    }

    // Load resource paths from data file using configfile ressource type
    Ogre::ConfigFile cf;
    try
    {
      cf.load(Settings::getDataPath() + resourceFile_);
    }
    catch (Ogre::Exception ex)
    {
      COUT(1) << "Error: Could not load resources.cfg in path " << Settings::getDataPath() << std::endl;
      COUT(0) << "Have you forgotten to set the data path in orxnox.ini?" << std::endl;
      return false;
    }

    // Go through all sections & settings in the file
    Ogre::ConfigFile::SectionIterator seci = cf.getSectionIterator();

    std::string secName, typeName, archName;
    while (seci.hasMoreElements())
    {
      try
      {
        secName = seci.peekNextKey();
        Ogre::ConfigFile::SettingsMultiMap *settings = seci.getNext();
        Ogre::ConfigFile::SettingsMultiMap::iterator i;
        for (i = settings->begin(); i != settings->end(); ++i)
        {
          typeName = i->first; // for instance "FileSystem" or "Zip"
          archName = i->second; // name (and location) of archive

          Ogre::ResourceGroupManager::getSingleton().addResourceLocation(
              std::string(Settings::getDataPath() + archName), typeName, secName);
        }
      }
      catch (Ogre::Exception ex)
      {
        COUT(2) << "Exception while reading resources.cfg. Proceeding.." << ex.getDescription() << std::endl;
      }
    }
    return true;
  }

  bool GraphicsEngine::loadRenderer()
  {
    CCOUT(4) << "Configuring Renderer" << std::endl;

    // check for file existence because Ogre displays exceptions if not
    std::ifstream probe;
    probe.open(ogreConfigFile_.c_str());
    if (!probe)
    {
      // create a zero sized file
      std::ofstream creator;
      creator.open(ogreConfigFile_.c_str());
      creator.close();
    }
    else
      probe.close();

    if (!root_->restoreConfig())
      if (!root_->showConfigDialog())
        return false;

    CCOUT(4) << "Creating render window" << std::endl;
    try
    {
      this->renderWindow_ = root_->initialise(true, "OrxonoxV2");
    }
    catch (Ogre::Exception ex)
    {
      COUT(2) << "Error: There was an exception when initialising Ogre Root." << std::endl;
      return false;
    }

    if (!root_->isInitialised())
    {
      CCOUT(2) << "Error: Initialising Ogre root object failed." << std::endl;
      return false;
    }
    Ogre::WindowEventUtilities::addWindowEventListener(this->renderWindow_, this);
    Ogre::TextureManager::getSingleton().setDefaultNumMipmaps(5);
    return true;
  }

  bool GraphicsEngine::initialiseResources()
  {
    CCOUT(4) << "Initialising resources" << std::endl;
    //TODO: Do NOT load all the groups, why are we doing that? And do we really do that? initialise != load...
    try
    {
      Ogre::ResourceGroupManager::getSingleton().initialiseAllResourceGroups();
      /*Ogre::StringVector str = Ogre::ResourceGroupManager::getSingleton().getResourceGroups();
      for (unsigned int i = 0; i < str.size(); i++)
      {
        Ogre::ResourceGroupManager::getSingleton().loadResourceGroup(str[i]);
      }*/
    }
    catch (Ogre::Exception e)
    {
      CCOUT(2) << "Error: There was an Error when initialising the resources." << std::endl;
      CCOUT(2) << "ErrorMessage: " << e.getFullDescription() << std::endl;
      return false;
    }
    return true;
  }

  /**
   * @brief Creates the SceneManager
   */
  bool GraphicsEngine::createNewScene()
  {
    CCOUT(4) << "Creating new SceneManager..." << std::endl;
    if (scene_)
    {
      CCOUT(2) << "SceneManager already exists! Skipping." << std::endl;
      return false;
    }
    scene_ = root_->createSceneManager(Ogre::ST_GENERIC, "Default SceneManager");
    CCOUT(3) << "Created SceneManager: " << scene_ << std::endl;
    return true;
  }

  /**
    Returns the window handle of the render window.
    At least the InputHandler uses this to create the OIS::InputManager
    @return The window handle of the render window
  */
  size_t GraphicsEngine::getWindowHandle()
  {
    if (this->renderWindow_)
    {
      size_t windowHnd = 0;
      this->renderWindow_->getCustomAttribute("WINDOW", &windowHnd);
      return windowHnd;
    }
    else
      return 0;
  }

  /**
    Get the width of the current render window
    @return The width of the current render window
  */
  int GraphicsEngine::getWindowWidth() const
  {
    if (this->renderWindow_)
      return this->renderWindow_->getWidth();
    else
      return 0;
  }

  /**
    Get the height of the current render window
    @return The height of the current render window
  */
  int GraphicsEngine::getWindowHeight() const
  {
    if (this->renderWindow_)
      return this->renderWindow_->getHeight();
    else
      return 0;
  }

  /**
    @brief Returns the window aspect ratio height/width.
    @return The ratio
  */
  float GraphicsEngine::getWindowAspectRatio() const
  {
    if (this->renderWindow_)
        return (float)this->renderWindow_->getHeight() / (float)this->renderWindow_->getWidth();
    else
        return 1.0f;
  }

  /**
    @brief Method called by the LogListener interface from Ogre.
    We use it to capture Ogre log messages and handle it ourselves.
    @param message The message to be logged
    @param lml The message level the log is using
    @param maskDebug If we are printing to the console or not
    @param logName the name of this log (so you can have several listeners
                   for different logs, and identify them)
  */
  void GraphicsEngine::messageLogged(const std::string& message,
    Ogre::LogMessageLevel lml, bool maskDebug, const std::string &logName)
  {
    int orxonoxLevel;
    switch (lml)
    {
      case Ogre::LML_TRIVIAL:
        orxonoxLevel = this->ogreLogLevelTrivial_;
        break;
      case Ogre::LML_NORMAL:
        orxonoxLevel = this->ogreLogLevelNormal_;
        break;
      case Ogre::LML_CRITICAL:
        orxonoxLevel = this->ogreLogLevelCritical_;
        break;
      default:
        orxonoxLevel = 0;
    }
    OutputHandler::getOutStream().setOutputLevel(orxonoxLevel)
        << "Ogre: " << message << std::endl;
  }

  /**
  * Window has moved.
  * @param rw The render window it occured in
  */
  void GraphicsEngine::windowMoved(Ogre::RenderWindow *rw)
  {
    for (Iterator<orxonox::WindowEventListener> it = ObjectList<orxonox::WindowEventListener>::start(); it; ++it)
      it->windowMoved();
  }

  /**
  * Window has resized.
  * @param rw The render window it occured in
  * @note GraphicsEngine has a render window stored itself. This is the same
  *       as rw. But we have to be careful when using multiple render windows!
  */
  void GraphicsEngine::windowResized(Ogre::RenderWindow *rw)
  {
    for (Iterator<orxonox::WindowEventListener> it = ObjectList<orxonox::WindowEventListener>::start(); it; ++it)
      it->windowResized(this->renderWindow_->getWidth(), this->renderWindow_->getHeight());
  }

  /**
  * Window has changed Focus.
  * @param rw The render window it occured in
  */
  void GraphicsEngine::windowFocusChanged(Ogre::RenderWindow *rw)
  {
    for (Iterator<orxonox::WindowEventListener> it = ObjectList<orxonox::WindowEventListener>::start(); it; ++it)
      it->windowFocusChanged();
  }

  /**
  * Window was closed.
  * @param rw The render window it occured in
  */
  void GraphicsEngine::windowClosed(Ogre::RenderWindow *rw)
  {
    // using CommandExecutor in order to avoid depending on Orxonox.h.
    CommandExecutor::execute("exit", false);
  }

}