// Copyright (C) 2008-2012 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h

#ifndef IRR_C_DYNAMIC_MESHBUFFER_H_INCLUDED
#define IRR_C_DYNAMIC_MESHBUFFER_H_INCLUDED

#include "IDynamicMeshBuffer.h"

#include "CVertexBuffer.h"
#include "CIndexBuffer.h"

namespace irr
{
namespace scene
{
	//! Implementation of the IMeshBuffer interface for which can work with 16 and 32 bit indices as well as different vertex types
	class CDynamicMeshBuffer: public IDynamicMeshBuffer
	{
	public:
		//! constructor
		CDynamicMeshBuffer(video::E_VERTEX_TYPE vertexType, video::E_INDEX_TYPE indexType)
		: PrimitiveType(EPT_TRIANGLES)
		{
			VertexBuffer=new CVertexBuffer(vertexType);
			IndexBuffer=new CIndexBuffer(indexType);
		}

		//! destructor
		virtual ~CDynamicMeshBuffer()
		{
			if (VertexBuffer)
				VertexBuffer->drop();
			if (IndexBuffer)
				IndexBuffer->drop();
		}

		virtual IVertexBuffer& getVertexBuffer() const IRR_OVERRIDE
		{
			return *VertexBuffer;
		}

		virtual IIndexBuffer& getIndexBuffer() const IRR_OVERRIDE
		{
			return *IndexBuffer;
		}

		virtual void setVertexBuffer(IVertexBuffer *newVertexBuffer) IRR_OVERRIDE
		{
			if (newVertexBuffer)
				newVertexBuffer->grab();
			if (VertexBuffer)
				VertexBuffer->drop();

			VertexBuffer=newVertexBuffer;
		}

		virtual void setIndexBuffer(IIndexBuffer *newIndexBuffer) IRR_OVERRIDE
		{
			if (newIndexBuffer)
				newIndexBuffer->grab();
			if (IndexBuffer)
				IndexBuffer->drop();

			IndexBuffer=newIndexBuffer;
		}

		//! Get Material of this buffer.
		virtual const video::SMaterial& getMaterial() const IRR_OVERRIDE
		{
			return Material;
		}

		//! Get Material of this buffer.
		virtual video::SMaterial& getMaterial() IRR_OVERRIDE
		{
			return Material;
		}

		//! Get bounding box
		virtual const core::aabbox3d<f32>& getBoundingBox() const IRR_OVERRIDE
		{
			return BoundingBox;
		}

		//! Set bounding box
		virtual void setBoundingBox( const core::aabbox3df& box) IRR_OVERRIDE
		{
			BoundingBox = box;
		}

		//! Recalculate bounding box
		virtual void recalculateBoundingBox() IRR_OVERRIDE
		{
			if (!getVertexBuffer().size())
				BoundingBox.reset(0,0,0);
			else
			{
				BoundingBox.reset(getVertexBuffer()[0].Pos);
				for (u32 i=1; i<getVertexBuffer().size(); ++i)
					BoundingBox.addInternalPoint(getVertexBuffer()[i].Pos);
			}
		}

		//! Append the vertices and indices to the current buffer
		/** Only works for compatible vertex types.
		\param vertices Pointer to a vertex array.
		\param numVertices Number of vertices in the array.
		\param indices Pointer to index array.
		\param numIndices Number of indices in array. */
		virtual void append(const void* const vertices, u32 numVertices, const u16* const indices, u32 numIndices, bool updateBoundingBox=true) IRR_OVERRIDE
		{
			// We simply assume it has the same vertex and index type as this object. If other types are passed this will crash
			append(getVertexType(), vertices, numVertices, getIndexType(), indices, numIndices, updateBoundingBox);
		}

		//! Append the meshbuffer to the current buffer
		/** \param other Buffer to append to this one. */
		virtual void append(const IMeshBuffer* const other, bool updateBoundingBox=true) IRR_OVERRIDE
		{
			append(other->getVertexType(), other->getVertices(), other->getVertexCount(), other->getIndexType(), other->getIndices(), other->getIndexCount(), updateBoundingBox);
		}

		void append(video::E_VERTEX_TYPE vertexType, const void* const vertices, u32 numVertices, video::E_INDEX_TYPE indexType, const void* const indices, u32 numIndices, bool updateBoundingBox)
		{
			if (vertices == getVertices() || indices == getIndices())	// can't do that because we're doing reallocations on those blocks
				return;

			const u32 vertexCount = getVertexCount();

			VertexBuffer->reallocate(vertexCount+numVertices, false);
			if ( vertexType == getVertexType() )
			{
				const irr::u32 typeSize = getVertexPitchFromType(vertexType);
				VertexBuffer->set_used(vertexCount+numVertices);
				irr::u8* target = &static_cast<irr::u8*>(VertexBuffer->pointer())[vertexCount*typeSize];
				memcpy(target, vertices, numVertices*typeSize);
			}
			else
			{
				switch ( vertexType )
				{
					case video::EVT_STANDARD:
						for (u32 i=0; i<numVertices; ++i)
						{
							VertexBuffer->push_back(static_cast<const video::S3DVertex*>(vertices)[i]);
						}
						break;
					case video::EVT_2TCOORDS:
						for (u32 i=0; i<numVertices; ++i)
						{
							VertexBuffer->push_back(static_cast<const video::S3DVertex2TCoords*>(vertices)[i]);
						}
						break;
					case video::EVT_TANGENTS:
						for (u32 i=0; i<numVertices; ++i)
						{
							VertexBuffer->push_back(static_cast<const video::S3DVertexTangents*>(vertices)[i]);
						}
						break;
				}
			}

			if ( updateBoundingBox && numVertices > 0)
			{
				if ( vertexCount == 0 )
					BoundingBox.reset( static_cast<const video::S3DVertex*>(vertices)[0].Pos );

				const u32 typePitch = getVertexPitchFromType(vertexType);
				const irr::u8* v8 = static_cast<const irr::u8*>(vertices);
				for (u32 i=0; i<numVertices; ++i, v8 += typePitch)
				{
					BoundingBox.addInternalPoint(reinterpret_cast<const video::S3DVertex*>(v8)->Pos);
				}
			}

			IndexBuffer->reallocate(getIndexCount()+numIndices, false);
			switch ( indexType )
			{
				case video::EIT_16BIT:
				{
					const irr::u16* indices16 = reinterpret_cast<const irr::u16*>(indices);
					for (u32 i=0; i<numIndices; ++i)
					{
						// Note: This can overflow, not checked. Will result in broken models, but no crashes.
						IndexBuffer->push_back(indices16[i]+vertexCount);
					}
					break;
				}
				case video::EIT_32BIT:
				{
					const irr::u32* indices32 = reinterpret_cast<const irr::u32*>(indices);
					for (u32 i=0; i<numIndices; ++i)
					{
						IndexBuffer->push_back(indices32[i]+vertexCount);
					}
					break;
				}
			}

			setDirty();
		}


		//! Describe what kind of primitive geometry is used by the meshbuffer
		virtual void setPrimitiveType(E_PRIMITIVE_TYPE type) IRR_OVERRIDE
		{
			PrimitiveType = type;
		}

		//! Get the kind of primitive geometry which is used by the meshbuffer
		virtual E_PRIMITIVE_TYPE getPrimitiveType() const IRR_OVERRIDE
		{
			return PrimitiveType;
		}

		//! Returns type of the class implementing the IMeshBuffer
		virtual EMESH_BUFFER_TYPE getType() const  IRR_OVERRIDE
		{
			return EMBT_DYNAMIC;
		}

		//! Create copy of the meshbuffer
		virtual IMeshBuffer* createClone(int cloneFlags) const IRR_OVERRIDE
		{
			CDynamicMeshBuffer* clone = new CDynamicMeshBuffer(VertexBuffer->getType(), IndexBuffer->getType());

			if (cloneFlags & ECF_VERTICES)
			{
				const u32 numVertices = VertexBuffer->size();
				clone->VertexBuffer->reallocate(numVertices);
				for ( u32 i=0; i<numVertices; ++i )
				{
					clone->VertexBuffer->push_back((*VertexBuffer)[i]);
				}
				clone->BoundingBox = BoundingBox;
			}

			if (cloneFlags & ECF_INDICES)
			{
				const u32 numIndices = IndexBuffer->size();
				clone->IndexBuffer->reallocate(numIndices);
				for ( u32 i=0; i<numIndices; ++i )
				{
					clone->IndexBuffer->push_back((*IndexBuffer)[i]);
				}
			}

			clone->VertexBuffer->setHardwareMappingHint(VertexBuffer->getHardwareMappingHint());
			clone->IndexBuffer->setHardwareMappingHint(clone->IndexBuffer->getHardwareMappingHint());
			clone->Material = Material;
			clone->PrimitiveType = PrimitiveType;

			return clone;
		}

		video::SMaterial Material;
		core::aabbox3d<f32> BoundingBox;
		//! Primitive type used for rendering (triangles, lines, ...)
		E_PRIMITIVE_TYPE PrimitiveType;
	private:
		CDynamicMeshBuffer(const CDynamicMeshBuffer&); // = delete in c++11, prevent copying

		IVertexBuffer *VertexBuffer;
		IIndexBuffer *IndexBuffer;
	};


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

#endif