///////////////////////////////////////////////////////////////////////////
//
//		Realistic rain real-time simulation program
//
//		Pierre Rousseau
//
///////////////////////////////////////////////////////////////////////////
//
//		Light Handling
//
///////////////////////////////////////////////////////////////////////////


#include "RainLight.h"










RainLight::RainLight(SceneManager *sceneMgr, int lightNumber, ColourValue col, Vector3 LightPos, float LightAttenuation)
{String name;

  mSceneMgr = sceneMgr;

  Vector3 decalage_ampoule(-5.5, 38, 0);
  
  Entity *mStreetLight = mSceneMgr->createEntity("Street_light_" + StringConverter::toString(lightNumber), "lampadaire.mesh");
  mStreetLight->setMaterialName("lampMat");
  
  mConeNode = NULL;
  SceneNode *mStreetLightNode = mSceneMgr->getRootSceneNode()->createChildSceneNode();
  mStreetLightNode->setPosition(LightPos);
  mStreetLightNode->setScale(0.8, 0.8, 0.8);
  mStreetLightNode->attachObject(mStreetLight);

  mLightNode = mStreetLightNode->createChildSceneNode(decalage_ampoule);

  name = "billboardSet_for_light" +  StringConverter::toString(lightNumber);
  mBillboardSet = sceneMgr->createBillboardSet(name);
  mLightNode->attachObject(mBillboardSet);
  mBillboardSet->setMaterialName("Examples/Flare");

  mBillboard = mBillboardSet->createBillboard(Vector3(0, 0, 0));
  mBillboard->setDimensions(8, 8);
  mBillboard->setColour(col);

  mColour = col;
  mLightPos = mLightNode->getWorldPosition();
  mLightDir = Vector3(-0.2, -1, 0).normalisedCopy();
  mLightCutoff = 35;
  mLightAttenuation = LightAttenuation;
}








void RainLight::animate()
{
  static Vector3 pos;
  static Vector3 dir;

  if (isAnimated)
  {
    h1 += stepH1 / 10.0;
    h2 += stepH2 / 10.0;
    h3 += stepH3 / 10.0;
    v1 += stepV1 / 10.0;
    v2 += stepV2 / 10.0;
/*
    pos = Vector3(sin(h1) * sin(h2) * 10.0, sin(v1) * sin(v2) * 3.0, (cos(h1) - 1.0) * (cos(h3) - 1.0) * 10.0);
    mLightPos = mLightInitialPos + pos;
    mLightNode->setPosition(mLightPos);

    mLightCutoff = sin(h3) * 60.0 + 30;
    
    if (mLightCutoff < 45)
    {
      //the cone is narrow, we scale over x and z
      mConeNode->setScale(tan(mLightCutoff * _PI / 180.0) * 2.0, 1.0, tan(mLightCutoff * _PI / 180.0) * 2.0);
    }
    else
    {
      mConeNode->setScale(1.0, 1.0 / (tan(mLightCutoff * _PI / 180.0) * 2.0), 1.0);
    }
*/

    dir = Vector3(sin(h1) * sin(h2), cos(h1), sin(h1) * cos(h2)).normalisedCopy();
	if (mConeNode)
	{
		mConeNode->resetOrientation();
		mConeNode->rotate(Vector3(0, 1, 0).getRotationTo(dir));
		mLightDir = dir;
	}
  }
}







//////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////
//////////
//////////	RainLightManager class
//////////
//////////////////////////////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////////////////////////////


RainLightManager::RainLightManager(SceneManager *sceneMgr)
{
  mSceneMgr = sceneMgr;
  lightCount = 0;
  lightVector.clear();
}



RainLightManager::~RainLightManager()
{}




void RainLightManager::addStreetLight(ColourValue col, Vector3 LightPos, float LightAttenuation)
{
  lightVector.push_back(new RainLight(mSceneMgr, lightCount, col, LightPos, LightAttenuation));

  ++lightCount;
}


/*
light info texture will contain information about a light source :
	- first pixel  : color
	- second pixel : position
	- third pixel  : direction (if spot)
	- fourth pixel : spot cutoff angle (180 for omnidirectional), distance attenuation (% / m)
*/

//void RainLightManager::createLightInfoTexture(int lightIndex, ColourValue col, Vector3 lightPosition, Vector3 lightDirection)
void RainLightManager::createLightInfoTexture()
{
  std::cout << std::endl << "    Creating light information texture " << std::endl << std::endl;


  TexturePtr DynamicLightInfoTexture = TextureManager::getSingleton().createManual(
                                         LIGHT_INFO_TEXTURE_NAME, // name
                                         ResourceGroupManager::DEFAULT_RESOURCE_GROUP_NAME,
                                         TEX_TYPE_2D,      // type
                                         4, lightCount,    // width & height
                                         0,                // number of mipmaps
                                         PF_FLOAT32_RGBA,     // pixel format
                                         TU_DYNAMIC_WRITE_ONLY_DISCARDABLE);

  // Get the pixel buffer
  HardwarePixelBufferSharedPtr pixelBuffer = DynamicLightInfoTexture->getBuffer();

  // Lock the pixel buffer and get a pixel box
  pixelBuffer->lock(HardwareBuffer::HBL_DISCARD);
  const PixelBox& pixelBox = pixelBuffer->getCurrentLock();

  float* pDest = static_cast<float*>(pixelBox.data);

  // Fill in some pixel data.

  for (int i = 0 ; i < lightCount ; i++ )
  {
    // we search for the data of each light
    ColourValue col = lightVector[i]->getColour();
    Vector3 pos = lightVector[i]->getPosition();
    Vector3 dir = lightVector[i]->getDirection();
    float cutoff = lightVector[i]->getCutoff();
    float att = lightVector[i]->getAttenuation();

    // first pixel : light color
    *pDest++ = col.r;
    *pDest++ = col.g;
    *pDest++ = col.b;
    *pDest++ = 1.0;
    // second pixel : light position
    *pDest++ = pos.x;
    *pDest++ = pos.y;
    *pDest++ = pos.z;
    *pDest++ = 1.0;
    // third pixel : light direction
    *pDest++ = dir.x;
    *pDest++ = dir.y;
    *pDest++ = dir.z;
    *pDest++ = 1.0;
    // fourth pixel : cutoff and attenuation
    *pDest++ = cutoff;
    *pDest++ = att;
    *pDest++ = 1.0;
    *pDest++ = 1.0;
  }
  // Unlock the pixel buffer
  pixelBuffer->unlock();

  DynamicLightInfoTexture->load();
}




void RainLightManager::updateLightInfoTexture()
{
  TexturePtr DynamicLightInfoTexture = TextureManager::getSingleton().getByName(LIGHT_INFO_TEXTURE_NAME);

  // Get the pixel buffer
  HardwarePixelBufferSharedPtr pixelBuffer = DynamicLightInfoTexture->getBuffer();

  // Lock the pixel buffer and get a pixel box
  pixelBuffer->lock(HardwareBuffer::HBL_DISCARD);
  const PixelBox& pixelBox = pixelBuffer->getCurrentLock();

  float* pDest = static_cast<float*>(pixelBox.data);

  // Fill in some pixel data.
  for (int i = 0 ; i < lightCount ; i++ )
  {
    // we search for the data of each light
    ColourValue col = lightVector[i]->getColour();
    Vector3 pos = lightVector[i]->getPosition();
    Vector3 dir = lightVector[i]->getDirection();
    float cutoff = lightVector[i]->getCutoff();
    float att = lightVector[i]->getAttenuation();

    // first pixel : light color
    *pDest++ = col.r;
    *pDest++ = col.g;
    *pDest++ = col.b;
    *pDest++ = 1.0;
    // second pixel : light position
    *pDest++ = pos.x;
    *pDest++ = pos.y;
    *pDest++ = pos.z;
    *pDest++ = 1.0;
    // third pixel : light direction
    *pDest++ = dir.x;
    *pDest++ = dir.y;
    *pDest++ = dir.z;
    *pDest++ = 1.0;
    // fourth pixel : cutoff and attenuation
    *pDest++ = cutoff;
    *pDest++ = att;
    *pDest++ = 1.0;
    *pDest++ = 1.0;
  }

  // Unlock the pixel buffer
  pixelBuffer->unlock();

  DynamicLightInfoTexture->load();
}



void RainLightManager::updateLights()
{
  for (int i = 0 ; i < lightCount ; i++ )
  {
    if (lightVector[i]->getIsAnimated())
    {
      lightVector[i]->animate();
    }
  }

  updateLightInfoTexture();
}




void RainLightManager::finalizeLights()
{
  createLightInfoTexture();
}