/*
   Copyright (C) 2001-2006, William Joseph.
   All Rights Reserved.

   This file is part of GtkRadiant.

   GtkRadiant 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.

   GtkRadiant 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 GtkRadiant; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#if !defined( INCLUDED_RENDERER_H )
#define INCLUDED_RENDERER_H

#include "irender.h"
#include "renderable.h"
#include "iselection.h"
#include "cullable.h"
#include "scenelib.h"
#include "math/frustum.h"
#include <vector>

inline Cullable* Instance_getCullable( scene::Instance& instance ){
	return InstanceTypeCast<Cullable>::cast( instance );
}

inline Renderable* Instance_getRenderable( scene::Instance& instance ){
	return InstanceTypeCast<Renderable>::cast( instance );
}

inline VolumeIntersectionValue Cullable_testVisible( scene::Instance& instance, const VolumeTest& volume, VolumeIntersectionValue parentVisible ){
	if ( parentVisible == c_volumePartial ) {
		Cullable* cullable = Instance_getCullable( instance );
		if ( cullable != 0 ) {
			return cullable->intersectVolume( volume, instance.localToWorld() );
		}
	}
	return parentVisible;
}

template<typename _Walker>
class CullingWalker
{
const VolumeTest& m_volume;
const _Walker& m_walker;
public:
CullingWalker( const VolumeTest& volume, const _Walker& walker )
	: m_volume( volume ), m_walker( walker ){
}
bool pre( const scene::Path& path, scene::Instance& instance, VolumeIntersectionValue parentVisible ) const {
	VolumeIntersectionValue visible = Cullable_testVisible( instance, m_volume, parentVisible );
	if ( visible != c_volumeOutside ) {
		return m_walker.pre( path, instance );
	}
	return true;
}
void post( const scene::Path& path, scene::Instance& instance, VolumeIntersectionValue parentVisible ) const {
	return m_walker.post( path, instance );
}
};

template<typename Walker_>
class ForEachVisible : public scene::Graph::Walker
{
const VolumeTest& m_volume;
const Walker_& m_walker;
mutable std::vector<VolumeIntersectionValue> m_state;
public:
ForEachVisible( const VolumeTest& volume, const Walker_& walker )
	: m_volume( volume ), m_walker( walker ){
	m_state.push_back( c_volumePartial );
}
bool pre( const scene::Path& path, scene::Instance& instance ) const {
	VolumeIntersectionValue visible = ( path.top().get().visible() ) ? m_state.back() : c_volumeOutside;

	if ( visible == c_volumePartial ) {
		visible = m_volume.TestAABB( instance.worldAABB() );
	}

	m_state.push_back( visible );

	if ( visible == c_volumeOutside ) {
		return false;
	}
	else
	{
		return m_walker.pre( path, instance, m_state.back() );
	}
}
void post( const scene::Path& path, scene::Instance& instance ) const {
	if ( m_state.back() != c_volumeOutside ) {
		m_walker.post( path, instance, m_state.back() );
	}

	m_state.pop_back();
}
};

template<typename Functor>
inline void Scene_forEachVisible( scene::Graph& graph, const VolumeTest& volume, const Functor& functor ){
	graph.traverse( ForEachVisible< CullingWalker<Functor> >( volume, CullingWalker<Functor>( volume, functor ) ) );
}

class RenderHighlighted
{
Renderer& m_renderer;
const VolumeTest& m_volume;
public:
RenderHighlighted( Renderer& renderer, const VolumeTest& volume )
	: m_renderer( renderer ), m_volume( volume ){
}
void render( const Renderable& renderable ) const {
	switch ( m_renderer.getStyle() )
	{
	case Renderer::eFullMaterials:
		renderable.renderSolid( m_renderer, m_volume );
		break;
	case Renderer::eWireframeOnly:
		renderable.renderWireframe( m_renderer, m_volume );
		break;
	}
}
typedef ConstMemberCaller1<RenderHighlighted, const Renderable&, &RenderHighlighted::render> RenderCaller;

bool pre( const scene::Path& path, scene::Instance& instance, VolumeIntersectionValue parentVisible ) const {
	m_renderer.PushState();

	if ( Cullable_testVisible( instance, m_volume, parentVisible ) != c_volumeOutside ) {
		Renderable* renderable = Instance_getRenderable( instance );
		if ( renderable ) {
			renderable->viewChanged();
		}

		Selectable* selectable = Instance_getSelectable( instance );
		if ( selectable != 0 && selectable->isSelected() ) {
			if ( GlobalSelectionSystem().Mode() != SelectionSystem::eComponent ) {
				m_renderer.Highlight( Renderer::eFace );
			}
			else if ( renderable ) {
				renderable->renderComponents( m_renderer, m_volume );
			}
			m_renderer.Highlight( Renderer::ePrimitive );
		}

		if ( renderable ) {
			render( *renderable );
		}
	}

	return true;
}
void post( const scene::Path& path, scene::Instance& instance, VolumeIntersectionValue parentVisible ) const {
	m_renderer.PopState();
}
};

inline void Scene_Render( Renderer& renderer, const VolumeTest& volume ){
	GlobalSceneGraph().traverse( ForEachVisible<RenderHighlighted>( volume, RenderHighlighted( renderer, volume ) ) );
	GlobalShaderCache().forEachRenderable( RenderHighlighted::RenderCaller( RenderHighlighted( renderer, volume ) ) );
}

#endif