/*
   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: Christian Meyer
   co-programmer: Benjamin Grauer
*/
#define DEBUG_SPECIAL_MODULE DEBUG_MODULE_WORLD_ENTITY

#include "camera.h"

#include "event_handler.h"

using namespace std;


/**
 *  creates a Camera
*/
Camera::Camera()
{
  this->setClassID(CL_CAMERA, "Camera");
  this->setName("camera");
  this->target = new CameraTarget();

  EventHandler::getInstance()->subscribe(this, ES_GAME, KeyMapper::PEV_VIEW0);
  EventHandler::getInstance()->subscribe(this, ES_GAME, KeyMapper::PEV_VIEW1);
  EventHandler::getInstance()->subscribe(this, ES_GAME, KeyMapper::PEV_VIEW2);
  EventHandler::getInstance()->subscribe(this, ES_GAME, KeyMapper::PEV_VIEW3);
  EventHandler::getInstance()->subscribe(this, ES_GAME, KeyMapper::PEV_VIEW4);
  EventHandler::getInstance()->subscribe(this, ES_GAME, KeyMapper::PEV_VIEW5);

  this->setFovy(90);
  this->setAspectRatio(1.2f);
  this->setClipRegion(.1, 2000);

  this->setViewMode(VIEW_NORMAL);

  this->setParentMode(PNODE_ALL);
}

/**
 *  default destructor
*/
Camera::~Camera()
{}

/**
 *  focuses the Camera onto a Target
 * @param target the new PNode the Camera should look at.
*/
void Camera::lookAt(PNode* target)
{
  this->target->setParent(target);
}

/**
 * @returns The PNode of the Target (from there you can get position and so on
*/
PNode* Camera::getTarget()
{
  return (PNode*)this->target;
}

/**
 *  sets a new AspectRatio
 * @param aspectRatio the new aspect ratio to set (width / height)
*/
void Camera::setAspectRatio(float aspectRatio)
{
  this->aspectRatio = aspectRatio;
}

/**
 *  sets the Field of View to fofy
 * @param fovy new field of view factor (in degrees)
*/
void Camera::setFovy(float fovy)
{
  this->fovy = fovy;
}

/**
 * Sets a new clipping region
 * @param nearClip The near clip plane
 * @param farClip The far clip plane
*/
void Camera::setClipRegion(float nearClip, float farClip)
{
  this->nearClip = nearClip;
  this->farClip = farClip;
}

/**
 *  sets the new VideoMode and initializes iteration to it.
 * @param mode the mode to change to.
*/
void Camera::setViewMode(ViewMode mode)
{
  currentMode = mode;
  switch (mode)
  {
    default:
    case VIEW_NORMAL:
      this->toFovy = 60.0;
      this->setRelCoorSoft(-10, 5, 0);
      this->target->setRelCoorSoft(0,0,0);
      break;
    case VIEW_BEHIND:
      break;
    case VIEW_FRONT:
      this->toFovy = 120.0;
      this->setRelCoorSoft(4, 0, 0, 5);
      this->target->setRelCoorSoft(Vector(10,0,0), 5);
      break;
    case VIEW_LEFT:
      this->toFovy = 90;
      this->setRelCoorSoft(0, 1, -10, .5);
      this->target->setRelCoorSoft(0,0,0);
      break;
    case VIEW_RIGHT:
      this->toFovy = 90;
      this->setRelCoorSoft(Vector(0, 1, 10));
      this->target->setRelCoorSoft(0,0,0);
      break;
    case VIEW_TOP:
      this->toFovy= 120;
      this->setRelCoorSoft(Vector(30, 50, 0));
      this->target->setRelCoorSoft(35,0,0);
  }
}


/**
 *  Updates the position of the camera.
 * @param dt: The time that elapsed.
*/
void Camera::tick(float dt)
{
  float tmpFovy = (this->toFovy - this->fovy) ;
  if (tmpFovy > 0.01)
    this->fovy += tmpFovy * fabsf(dt);
}


/**
 *  initialize rendering perspective according to this camera
 *
 * This is called immediately before the rendering cycle starts, it sets all global
 * rendering options as well as the GL_PROJECTION matrix according to the camera.
 */
void Camera::apply ()
{
  // switching to Projection Matrix
  glMatrixMode (GL_PROJECTION);
  glLoadIdentity ();

  gluPerspective(this->fovy,
                 this->aspectRatio,
                 this->nearClip,
                 this->farClip);


    // setting up the perspective
  // speed-up feature
  Vector cameraPosition = this->getAbsCoor();
  Vector targetPosition = this->target->getAbsCoor();
  Vector up = this->getAbsDirV();
  Vector delay = Vector(0, 0, 0);
  if( currentMode != VIEW_FRONT) delay = (this->target->getVelocity()) / 25.0f;

   // Setting the Camera Eye, lookAt and up Vectors
  gluLookAt(cameraPosition.x - delay.x, cameraPosition.y - delay.y, cameraPosition.z - delay.z,
            targetPosition.x, targetPosition.y, targetPosition.z,
            up.x, up.y, up.z);


  glMatrixMode (GL_MODELVIEW);
  glLoadIdentity();

}

/**
 *  processes an event
 * @param event: the event to process
*/
void Camera::process(const Event &event)
{
  if( event.type == KeyMapper::PEV_VIEW0)
  {
    this->setViewMode(VIEW_NORMAL);
  }
  else if( event.type == KeyMapper::PEV_VIEW1)
  {
    this->setViewMode(VIEW_BEHIND);
  }
  else if( event.type == KeyMapper::PEV_VIEW2)
  {
    this->setViewMode(VIEW_FRONT);
  }
  else if( event.type == KeyMapper::PEV_VIEW3)
  {
    this->setViewMode(VIEW_LEFT);
  }
  else if( event.type == KeyMapper::PEV_VIEW4)
  {
    this->setViewMode(VIEW_RIGHT);
  }
  else if( event.type == KeyMapper::PEV_VIEW5)
  {
    this->setViewMode(VIEW_TOP);
  }
}


///////////////////
// CAMERA-TARGET //
///////////////////


CameraTarget::CameraTarget()
{
  this->setClassID(CL_CAMERA_TARGET, "CameraTarget");
  //  this->setParentMode(PNODE_MOVEMENT);
}