/*
   orxonox - the future of 3D-vertical-scrollers

   Copyright (C) 2004 orx

   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, or (at your option)
   any later version.

   ### File Specific:
   main-programmer: Patrick Boenzli
   co-programmer: Christian Meyer
   co-programmer: Benjamin Grauer
*/

#define DEBUG_SPECIAL_MODULE DEBUG_MODULE_WORLD

#include "game_world.h"

#include "shell_command.h"
#include "resource_manager.h"
#include "state.h"

#include "p_node.h"
#include "world_entity.h"
#include "player.h"
#include "camera.h"
#include "environment.h"
#include "terrain.h"

#include "test_entity.h"
#include "terrain.h"
#include "light.h"
#include "load_param.h"
#include "shell.h"

#include "fast_factory.h"
#include "animation_player.h"
#include "particle_engine.h"
#include "graphics_engine.h"
#include "physics_engine.h"
#include "fields.h"

#include "md2Model.h"

#include "glmenu_imagescreen.h"
#include "game_loader.h"

#include "animation3d.h"

#include "substring.h"

#include "factory.h"

#include "weapons/projectile.h"
#include "event_handler.h"
#include "sound_engine.h"
#include "ogg_player.h"

#include "class_list.h"

#include "cd_engine.h"
#include "npcs/npc_test1.h"
#include "shader.h"

#include "playable.h"
#include "network_manager.h"
#include "playable.h"


SHELL_COMMAND(speed, GameWorld, setSpeed);
SHELL_COMMAND(togglePNodeVisibility, GameWorld, togglePNodeVisibility);
SHELL_COMMAND(toggleBVVisibility, GameWorld, toggleBVVisibility);

using namespace std;

//! This creates a Factory to fabricate a GameWorld
CREATE_FACTORY(GameWorld, CL_GAME_WORLD);



GameWorld::GameWorld(const TiXmlElement* root)
{
  this->setClassID(CL_GAME_WORLD, "GameWorld");
  this->setName("Preloaded World - no name yet");

  this->gameTime = 0.0f;
  this->setSpeed(1.0f);
  this->music = NULL;
  this->shell = NULL;
  this->localPlayer = NULL;
  this->localCamera = NULL;

  this->showPNodes = false;
  this->showBV = false;

  this->path = NULL;

  this->loadParams(root);
}

/**
 *  remove the GameWorld from memory
 *
 *  delete everything explicitly, that isn't contained in the parenting tree!
 *  things contained in the tree are deleted automaticaly
 */
GameWorld::~GameWorld ()
{
  delete this->shell;
  PRINTF(3)("GameWorld::~GameWorld() - deleting current world\n");

  delete this->localPlayer;

  // delete all the initialized Engines.
  FastFactory::flushAll(true);
  delete LightManager::getInstance();
  delete ParticleEngine::getInstance();
  delete AnimationPlayer::getInstance();
  delete PhysicsEngine::getInstance();

  // external engines initialized by the orxonox-class get deleted
  SoundEngine::getInstance()->flushAllBuffers();
  SoundEngine::getInstance()->flushAllSources();

  if (State::getObjectManager() == &this->objectManager)
    State::setObjectManager(NULL);
  // erease everything that is left.
  delete PNode::getNullParent();

  //secondary cleanup of PNodes;
  const std::list<BaseObject*>* nodeList = ClassList::getList(CL_PARENT_NODE);
  if (nodeList != NULL)
    while (!nodeList->empty())
      delete nodeList->front();

  Shader::suspendShader();

  // unload the resources !!
  ResourceManager::getInstance()->unloadAllByPriority(RP_LEVEL);
}



/**
 * loads the parameters of a GameWorld from an XML-element
 * @param root the XML-element to load from
 */
void GameWorld::loadParams(const TiXmlElement* root)
{
  PRINTF(4)("Creating a GameWorld\n");

  LoadParam(root, "identifier", this, GameWorld, setStoryID)
    .describe("Sets the StoryID of this world");

  LoadParam(root, "nextid", this, GameWorld, setNextStoryID)
    .describe("Sets the ID of the next world");

  LoadParam(root, "path", this, GameWorld, setPath)
    .describe("The Filename of this GameWorld (relative from the data-dir)");
}


/**
 * this is executed just before load
 *
 * since the load function sometimes needs data, that has been initialized
 * before the load and after the proceeding storyentity has finished
*/
ErrorMessage GameWorld::init()
{
  State::setObjectManager(&this->objectManager);
  this->cycle = 0;

  /* init the world interface */
  this->shell = new Shell();

  LightManager::getInstance();
  PNode::getNullParent();

  AnimationPlayer::getInstance(); // initializes the animationPlayer
  ParticleEngine::getInstance();
  PhysicsEngine::getInstance();

  this->localCamera = new Camera();
  this->localCamera->setName ("GameWorld-Camera");

  State::setCamera(this->localCamera, this->localCamera->getTarget());

  GraphicsEngine::getInstance()->displayFPS(true);
}


/**
 *  loads the GameWorld by initializing all resources, and set their default values.
 */
ErrorMessage GameWorld::loadData()
{
  this->displayLoadScreen();

  PRINTF(3)("> Loading world: '%s'\n", getPath());
  TiXmlElement* element;
  GameLoader* loader = GameLoader::getInstance();

  if( getPath() == NULL)
    {
      PRINTF(1)("GameWorld has no path specified for loading");
      return (ErrorMessage){213,"Path not specified","GameWorld::load()"};
    }

  TiXmlDocument* XMLDoc = new TiXmlDocument( getPath());
  // load the campaign document
  if( !XMLDoc->LoadFile())
  {
    // report an error
    PRINTF(1)("loading XML File: %s @ %s:l%d:c%d\n", XMLDoc->ErrorDesc(), this->getPath(), XMLDoc->ErrorRow(), XMLDoc->ErrorCol());
    delete XMLDoc;
    return (ErrorMessage){213,"XML File parsing error","GameWorld::load()"};
  }

  // check basic validity
  TiXmlElement* root = XMLDoc->RootElement();
  assert( root != NULL);

  if( root == NULL || root->Value() == NULL || strcmp( root->Value(), "WorldDataFile"))
    {
      // report an error
      PRINTF(1)("Specified XML File is not an orxonox world data file (WorldDataFile element missing)\n");
      delete XMLDoc;
      return (ErrorMessage){213,"Path not a WorldDataFile","GameWorld::load()"};
    }

  // load the parameters
  // name
  const char* string = grabParameter( root, "name");
  if( string == NULL)
    {
      PRINTF(2)("GameWorld is missing a proper 'name'\n");
      this->setName("Unknown");
    }
  else
    {
      this->setName(string);
    }

  ////////////////
  // LOADSCREEN //
  ////////////////
  element = root->FirstChildElement("LoadScreen");
  if (element == NULL)
    {
      PRINTF(2)("no LoadScreen specified, loading default\n");

      glmis->setBackgroundImage("pictures/load_screen.jpg");
      this->glmis->setMaximum(8);
      this->glmis->draw();
    }
  else
    {
      this->glmis->loadParams(element);
      this->glmis->draw();
    }
  this->glmis->draw();

  ////////////////////////
  // find WorldEntities //
  ////////////////////////

  element = root->FirstChildElement("WorldEntities");

  if( element == NULL)
    {
      PRINTF(1)("GameWorld is missing 'WorldEntities'\n");
    }
  else
    {
      element = element->FirstChildElement();
      // load Players/Objects/Whatever
      PRINTF(4)("Loading WorldEntities\n");
      while( element != NULL)
        {
          BaseObject* created = Factory::fabricate(element);
          if( created != NULL )
          {
            if(created->isA(CL_WORLD_ENTITY))
              this->spawn(dynamic_cast<WorldEntity*>(created));
            printf("Created a %s: %s\n", created->getClassName(), created->getName());
          }

          // if we load a 'Player' we use it as localPlayer


          //todo do this more elegant
          if( element->Value() != NULL && !strcmp( element->Value(), "SkyBox"))
            this->sky = dynamic_cast<WorldEntity*>(created);
          if( element->Value() != NULL && !strcmp( element->Value(), "Terrain"))
          {
            terrain = dynamic_cast<Terrain*>(created);
            CDEngine::getInstance()->setTerrain(terrain);
          }
          element = element->NextSiblingElement();
          glmis->step(); //! @todo temporary
        }
      PRINTF(4)("Done loading WorldEntities\n");
    }

    //////////////////////////////
    // LOADING ADDITIONAL STUFF //
    //////////////////////////////

    LoadParamXML(root, "LightManager", LightManager::getInstance(), LightManager, loadParams);

   LoadParamXML(root, "ParticleEngine", ParticleEngine::getInstance(), ParticleEngine, loadParams);
//   LoadParamXML(root, "PhysicsEngine", PhysicsEngine::getInstance(), PhysicsEngine, loadParams);

  // free the XML data

  delete XMLDoc;
  /* GENERIC LOADING PROCESS FINISHED */


  // Create a Player
  this->localPlayer = new Player();

  Playable* playable;
  const list<BaseObject*>* playableList = ClassList::getList(CL_PLAYABLE);
  if (playableList != NULL)
  {
    playable = dynamic_cast<Playable*>(playableList->front());
    this->localPlayer->setControllable(playable);
  }


//   //localCamera->setParent(TrackNode::getInstance());
//  tn->addChild(this->localCamera);
  localCamera->setClipRegion(1, 10000.0);
//  localCamera->lookAt(playable);
//  this->localPlayer->setParentMode(PNODE_ALL);
  if (this->sky != NULL)
  {
    this->localCamera->addChild(sky);
  }
  SoundEngine::getInstance()->setListener(this->localCamera);

  /* some static stuff*/

  this->music = NULL;
  //(OggPlayer*)ResourceManager::getInstance()->load("sound/00-luke_grey_-_hypermode.ogg", OGG, RP_LEVEL);
  //music->playback();

  this->releaseLoadScreen();
}


/**
 *  initializes a new GameWorld shortly before start
 *
 * this is the function, that will be loaded shortly before the world is
 * started
*/
ErrorMessage GameWorld::preStart()
{
  this->bPause = false;

  /* update the object position before game start - so there are no wrong coordinates used in the first processing */
  PNode::getNullParent()->updateNode (0.001f);
  PNode::getNullParent()->updateNode (0.001f);
}


/**
 *  starts the GameWorld
 */
ErrorMessage GameWorld::start()
{
  this->bQuitWorld = false;
  this->mainLoop();
}

/**
 *  stops the world.

   This happens, when the player decides to end the Level.
*/
ErrorMessage GameWorld::stop()
{
  PRINTF(3)("GameWorld::stop() - got stop signal\n");
  this->bQuitWorld= true;
}

/**
 *  pauses the Game
*/
ErrorMessage GameWorld::pause()
{
  this->isPaused = true;
}

/**
 *  ends the pause Phase
*/
ErrorMessage GameWorld::resume()
{
  this->isPaused = false;
}


/**
 *  shows the loading screen
*/
void GameWorld::displayLoadScreen ()
{
  PRINTF(3)("GameWorld::displayLoadScreen - start\n");

  //GLMenuImageScreen*
  this->glmis = new GLMenuImageScreen();
  this->glmis->setMaximum(8);

  PRINTF(3)("GameWorld::displayLoadScreen - end\n");
}

/**
 * @brief removes the loadscreen, and changes over to the game
 *
 * @todo take out the delay
*/
void GameWorld::releaseLoadScreen ()
{
  PRINTF(3)("GameWorld::releaseLoadScreen - start\n");
  this->glmis->setValue(this->glmis->getMaximum());
  PRINTF(3)("GameWorld::releaseLoadScreen - end\n");
  delete this->glmis;
}


/**
 *  synchronize local data with remote data
*/
void GameWorld::synchronize ()
{
  // Get remote input
  // Update synchronizables
/*  NetworkManager::getInstance()->synchronize();*/
}


/**
 *  run all input processing

   the command node is the central input event dispatcher. the node uses the even-queue from
   sdl and has its own event-passing-queue.
*/
void GameWorld::handleInput ()
{
  EventHandler::getInstance()->process();

  // remoteinput
}

void GameWorld::tick(std::list<WorldEntity*> entityList, float dt)
{
  std::list<WorldEntity*>::iterator entity;
  for (entity = entityList.begin(); entity != entityList.end(); entity++)
    (*entity)->tick(dt);

}

/**
 *  advance the timeline

   this calculates the time used to process one frame (with all input handling, drawing, etc)
   the time is mesured in ms and passed to all world-entities and other classes that need
   a heart-beat.
*/
void GameWorld::tick ()
{
  Uint32 currentFrame = SDL_GetTicks();
  if(!this->bPause)
    {
      this->dt = currentFrame - this->lastFrame;

      if( this->dt > 10)
        {
          float fps = 1000/dt;

          // temporary, only for showing how fast the text-engine is
          char tmpChar[20];
          sprintf(tmpChar, "fps: %4.0f", fps);
        }
      else
        {
          /* the frame-rate is limited to 100 frames per second, all other things are for
             nothing.
          */
          PRINTF(3)("fps = 1000 - frame rate is adjusted\n");
          SDL_Delay(10-dt);
          this->dt = 10;
        }

      this->dtS = (float)this->dt / 1000.0 * this->speed;
      this->gameTime += this->dtS;

      this->tick(this->objectManager.getObjectList(OM_DEAD_TICK), this->dtS);
      this->tick(this->objectManager.getObjectList(OM_COMMON), this->dtS);
      this->tick(this->objectManager.getObjectList(OM_GROUP_00), this->dtS);
      this->tick(this->objectManager.getObjectList(OM_GROUP_01), this->dtS);
      this->tick(this->objectManager.getObjectList(OM_GROUP_01_PROJ), this->dtS);

      /* update tick the rest */
      this->localCamera->tick(this->dtS);
      // tick the engines
      AnimationPlayer::getInstance()->tick(this->dtS);
//      if (this->cycle > 5)
        PhysicsEngine::getInstance()->tick(this->dtS);

      ParticleEngine::getInstance()->tick(this->dtS);


      /** actualy the Graphics Engine should tick the world not the other way around...
         but since we like the things not too complicated we got it this way around
         until there is need or time to do it the other way around.
         @todo: GraphicsEngine ticks world: separation of processes and data...

        bensch: in my opinion the GraphicsEngine could draw the world, but not tick it,
         beceause graphics have nothing(or at least not much) to do with Motion.
      */
      GraphicsEngine::getInstance()->tick(this->dtS);
    }
  this->lastFrame = currentFrame;
}


/**
 *  this function gives the world a consistant state

   after ticking (updating the world state) this will give a constistant
   state to the whole system.
*/
void GameWorld::update()
{
  GraphicsEngine::getInstance()->update(this->dtS);
  PNode::getNullParent()->updateNode (this->dtS);
  SoundEngine::getInstance()->update();
  //music->update();
}


void GameWorld::collide()
{
  CDEngine::getInstance()->checkCollisions(this->objectManager.getObjectList(OM_GROUP_00),
                                            this->objectManager.getObjectList(OM_GROUP_01_PROJ));
  CDEngine::getInstance()->checkCollisions(this->objectManager.getObjectList(OM_GROUP_01),
                                            this->objectManager.getObjectList(OM_COMMON));
}

/**
 *  render the current frame

   clear all buffers and draw the world
*/
void GameWorld::display ()
{
  // clear buffer
  glClear( GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
  // set camera
  this->localCamera->apply ();
  // draw world
  this->draw();
  // draw HUD
  /** @todo draw HUD */
  // flip buffers
  GraphicsEngine::swapBuffers();
  //SDL_Surface* screen = Orxonox::getInstance()->getScreen ();
  //SDL_Flip (screen);
}


/**
 *  runs through all entities calling their draw() methods
 */
void GameWorld::draw ()
{
  GraphicsEngine* engine = GraphicsEngine::getInstance();
  engine->draw(State::getObjectManager()->getObjectList(OM_ENVIRON_NOTICK));
  engine->draw(State::getObjectManager()->getObjectList(OM_ENVIRON));
  engine->draw(State::getObjectManager()->getObjectList(OM_COMMON));
  engine->draw(State::getObjectManager()->getObjectList(OM_GROUP_00));
  engine->draw(State::getObjectManager()->getObjectList(OM_GROUP_01));
  engine->draw(State::getObjectManager()->getObjectList(OM_GROUP_01_PROJ));

   if( unlikely( this->showBV))  // to draw the bounding boxes of the objects at level 2 for debug purp
   {
     CDEngine* engine = CDEngine::getInstance();
     engine->drawBV(State::getObjectManager()->getObjectList(OM_ENVIRON_NOTICK));
     engine->drawBV(State::getObjectManager()->getObjectList(OM_ENVIRON));
     engine->drawBV(State::getObjectManager()->getObjectList(OM_COMMON));
     engine->drawBV(State::getObjectManager()->getObjectList(OM_GROUP_00));
     engine->drawBV(State::getObjectManager()->getObjectList(OM_GROUP_01));
     engine->drawBV(State::getObjectManager()->getObjectList(OM_GROUP_01_PROJ));
   }

//   {
//     if( entity->isVisible() ) entity->draw();
  //FIXME
//     entity = iterator->nextElement();
//   }

  ParticleEngine::getInstance()->draw();

  if (unlikely(this->showPNodes))
    PNode::getNullParent()->debugDraw(0);

  engine->draw();
  //TextEngine::getInstance()->draw();
}


/**
 * \brief main loop of the world: executing all world relevant function
 *
 * in this loop we synchronize (if networked), handle input events, give the heart-beat to
 * all other member-entities of the world (tick to player, enemies etc.), checking for
 * collisions drawing everything to the screen.
 */
void GameWorld::mainLoop()
{
  this->lastFrame = SDL_GetTicks ();
  PRINTF(3)("GameWorld::mainLoop() - Entering main loop\n");

  while(!this->bQuitWorld) /* @todo implement pause */
  {
    ++this->cycle;
      // Network
    this->synchronize ();
      // Process input
    this->handleInput ();
    if( this->bQuitWorld)
      break;
      // Process time
    this->tick ();
      // Process collision
    this->collide ();
      // Update the state
    this->update ();
      // Draw
    this->display ();
  }

  PRINTF(3)("GameWorld::mainLoop() - Exiting the main loop\n");
}



/**
 *  add and spawn a new entity to this world
 * @param entity to be added
*/
void GameWorld::spawn(WorldEntity* entity)
{
//   this->entities->add (entity);
  entity->postSpawn ();
}

/**
 *  sets the track path of this world
 * @param name the name of the path
 */
void GameWorld::setPath( const char* name)
{
  if (this->path)
    delete this->path;
  if (ResourceManager::isFile(name))
  {
    this->path = new char[strlen(name)+1];
    strcpy(this->path, name);
  }
  else
    {
      this->path = new char[strlen(ResourceManager::getInstance()->getDataDir()) + strlen(name) +1];
      sprintf(this->path, "%s%s", ResourceManager::getInstance()->getDataDir(), name);
    }
}