// Copyright (C) 2002-2011 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h

#include "CLightSceneNode.h"
#include "IVideoDriver.h"
#include "ISceneManager.h"
#include "ICameraSceneNode.h"

#include "os.h"

namespace irr
{
namespace scene
{

//! constructor
CLightSceneNode::CLightSceneNode(ISceneNode* parent, ISceneManager* mgr, s32 id,
		const core::vector3df& position, video::SColorf color, f32 radius)
: ILightSceneNode(parent, mgr, id, position), DriverLightIndex(-1), LightIsOn(true)
{
	#ifdef _DEBUG
	setDebugName("CLightSceneNode");
	#endif

	LightData.DiffuseColor = color;
	// set some useful specular color
	LightData.SpecularColor = color.getInterpolated(video::SColor(255,255,255,255),0.7f);

	setRadius(radius);
}


//! pre render event
void CLightSceneNode::OnRegisterSceneNode()
{
	doLightRecalc();

	if (IsVisible)
		SceneManager->registerNodeForRendering(this, ESNRP_LIGHT);

	ISceneNode::OnRegisterSceneNode();
}


//! render
void CLightSceneNode::render()
{
	video::IVideoDriver* driver = SceneManager->getVideoDriver();
	if (!driver)
		return;

	if ( DebugDataVisible & scene::EDS_BBOX )
	{
		driver->setTransform(video::ETS_WORLD, AbsoluteTransformation);
		video::SMaterial m;
		m.Lighting = false;
		driver->setMaterial(m);

		switch ( LightData.Type )
		{
			case video::ELT_POINT:
			case video::ELT_SPOT:
				driver->draw3DBox(BBox, LightData.DiffuseColor.toSColor());
				break;

			case video::ELT_DIRECTIONAL:
				driver->draw3DLine(core::vector3df(0.f, 0.f, 0.f),
						LightData.Direction * LightData.Radius,
						LightData.DiffuseColor.toSColor());
				break;
		}
	}

	DriverLightIndex = driver->addDynamicLight(LightData);
	setVisible(LightIsOn);
}


//! sets the light data
void CLightSceneNode::setLightData(const video::SLight& light)
{
	LightData = light;
}


//! \return Returns the light data.
const video::SLight& CLightSceneNode::getLightData() const
{
	return LightData;
}


//! \return Returns the light data.
video::SLight& CLightSceneNode::getLightData()
{
	return LightData;
}

void CLightSceneNode::setVisible(bool isVisible)
{
	ISceneNode::setVisible(isVisible);

	if(DriverLightIndex < 0)
		return;
	video::IVideoDriver* driver = SceneManager->getVideoDriver();
	if (!driver)
		return;

	LightIsOn = isVisible;
	driver->turnLightOn((u32)DriverLightIndex, LightIsOn);
}

//! returns the axis aligned bounding box of this node
const core::aabbox3d<f32>& CLightSceneNode::getBoundingBox() const
{
	return BBox;
}


//! Sets the light's radius of influence.
/** Outside this radius the light won't lighten geometry and cast no
shadows. Setting the radius will also influence the attenuation, setting
it to (0,1/radius,0). If you want to override this behavior, set the
attenuation after the radius.
\param radius The new radius. */
void CLightSceneNode::setRadius(f32 radius)
{
	LightData.Radius=radius;
	LightData.Attenuation.set(0.f, 1.f/radius, 0.f);
	doLightRecalc();
}


//! Gets the light's radius of influence.
/** \return The current radius. */
f32 CLightSceneNode::getRadius() const
{
	return LightData.Radius;
}


//! Sets the light type.
/** \param type The new type. */
void CLightSceneNode::setLightType(video::E_LIGHT_TYPE type)
{
	LightData.Type=type;
}


//! Gets the light type.
/** \return The current light type. */
video::E_LIGHT_TYPE CLightSceneNode::getLightType() const
{
	return LightData.Type;
}


//! Sets whether this light casts shadows.
/** Enabling this flag won't automatically cast shadows, the meshes
will still need shadow scene nodes attached. But one can enable or
disable distinct lights for shadow casting for performance reasons.
\param shadow True if this light shall cast shadows. */
void CLightSceneNode::enableCastShadow(bool shadow)
{
	LightData.CastShadows=shadow;
}


//! Check whether this light casts shadows.
/** \return True if light would cast shadows, else false. */
bool CLightSceneNode::getCastShadow() const
{
	return LightData.CastShadows;
}


void CLightSceneNode::doLightRecalc()
{
	if ((LightData.Type == video::ELT_SPOT) || (LightData.Type == video::ELT_DIRECTIONAL))
	{
		LightData.Direction = core::vector3df(.0f,.0f,1.0f);
		getAbsoluteTransformation().rotateVect(LightData.Direction);
		LightData.Direction.normalize();
	}
	if ((LightData.Type == video::ELT_SPOT) || (LightData.Type == video::ELT_POINT))
	{
		const f32 r = LightData.Radius * LightData.Radius * 0.5f;
		BBox.MaxEdge.set( r, r, r );
		BBox.MinEdge.set( -r, -r, -r );
		//setAutomaticCulling( scene::EAC_BOX );
		setAutomaticCulling( scene::EAC_OFF );
		LightData.Position = getAbsolutePosition();
	}
	if (LightData.Type == video::ELT_DIRECTIONAL)
	{
		BBox.reset( 0, 0, 0 );
		setAutomaticCulling( scene::EAC_OFF );
	}
}


//! Writes attributes of the scene node.
void CLightSceneNode::serializeAttributes(io::IAttributes* out, io::SAttributeReadWriteOptions* options) const
{
	ILightSceneNode::serializeAttributes(out, options);

	out->addColorf	("AmbientColor", LightData.AmbientColor);
	out->addColorf	("DiffuseColor", LightData.DiffuseColor);
	out->addColorf	("SpecularColor", LightData.SpecularColor);
	out->addVector3d("Attenuation", LightData.Attenuation);
	out->addFloat	("Radius", LightData.Radius);
	out->addFloat	("OuterCone", LightData.OuterCone);
	out->addFloat	("InnerCone", LightData.InnerCone);
	out->addFloat	("Falloff", LightData.Falloff);
	out->addBool	("CastShadows", LightData.CastShadows);
	out->addEnum	("LightType", LightData.Type, video::LightTypeNames);
}

//! Reads attributes of the scene node.
void CLightSceneNode::deserializeAttributes(io::IAttributes* in, io::SAttributeReadWriteOptions* options)
{
	LightData.AmbientColor =	in->getAttributeAsColorf("AmbientColor");
	LightData.DiffuseColor =	in->getAttributeAsColorf("DiffuseColor");
	LightData.SpecularColor =	in->getAttributeAsColorf("SpecularColor");

	//TODO: clearify Radius and Linear Attenuation
#if 0
	setRadius ( in->getAttributeAsFloat("Radius") );
#else
	LightData.Radius = in->getAttributeAsFloat("Radius");
#endif

	if (in->existsAttribute("Attenuation")) // might not exist in older files
		LightData.Attenuation =	in->getAttributeAsVector3d("Attenuation");

	if (in->existsAttribute("OuterCone")) // might not exist in older files
		LightData.OuterCone =	in->getAttributeAsFloat("OuterCone");
	if (in->existsAttribute("InnerCone")) // might not exist in older files
		LightData.InnerCone =	in->getAttributeAsFloat("InnerCone");
	if (in->existsAttribute("Falloff")) // might not exist in older files
		LightData.Falloff =	in->getAttributeAsFloat("Falloff");
	LightData.CastShadows =		in->getAttributeAsBool("CastShadows");
	LightData.Type =		(video::E_LIGHT_TYPE)in->getAttributeAsEnumeration("LightType", video::LightTypeNames);

	doLightRecalc ();

	ILightSceneNode::deserializeAttributes(in, options);
}

//! Creates a clone of this scene node and its children.
ISceneNode* CLightSceneNode::clone(ISceneNode* newParent, ISceneManager* newManager)
{
	if (!newParent)
		newParent = Parent;
	if (!newManager)
		newManager = SceneManager;

	CLightSceneNode* nb = new CLightSceneNode(newParent,
		newManager, ID, RelativeTranslation, LightData.DiffuseColor, LightData.Radius);

	nb->cloneMembers(this, newManager);
	nb->LightData = LightData;
	nb->BBox = BBox;

	if ( newParent )
		nb->drop();
	return nb;
}

} // end namespace scene
} // end namespace irr

