// Copyright (C) 2017 Michael Zeilfelder
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h

#ifndef __S_OVERRIDE_MATERIAL_H_INCLUDED__
#define __S_OVERRIDE_MATERIAL_H_INCLUDED__

#include "SMaterial.h"

namespace irr
{
namespace video
{

	struct SOverrideMaterial
	{
		//! The Material values
		SMaterial Material;

		//! Which values are overridden
		/** OR'ed values from E_MATERIAL_FLAGS. */
		u32 EnableFlags;

		//! For those flags in EnableFlags which affect layers, set which of the layers are affected
		bool EnableLayerFlags[MATERIAL_MAX_TEXTURES];

		//! Which textures are overridden
		bool EnableTextures[MATERIAL_MAX_TEXTURES];

		//! Overwrite complete layers (settings of EnableLayerFlags and EnableTextures don't matter then for layer data)
		bool EnableLayers[MATERIAL_MAX_TEXTURES];

		//! Set in which render passes the material override is active.
		/** OR'ed values from E_SCENE_NODE_RENDER_PASS. */
		u16 EnablePasses;

		//! Global enable flag, overwritten by the SceneManager in each pass
		/** The Scenemanager uses the EnablePass array and sets Enabled to
		true if the Override material is enabled in the current pass. */
		bool Enabled;

		//! Default constructor
		SOverrideMaterial() : EnableFlags(0), EnablePasses(0), Enabled(false) 
		{
			for ( int i=0; i<MATERIAL_MAX_TEXTURES; ++i)
			{
				EnableLayerFlags[i] = true;
				EnableTextures[i] = false;
				EnableLayers[i] = false;
			}
		}

		//! Apply the enabled overrides
		void apply(SMaterial& material)
		{
			if (Enabled)
			{
				for (u32 i=0; i<32; ++i)
				{
					const u32 num=(1<<i);
					if (EnableFlags & num)
					{
						switch (num)
						{
						case EMF_WIREFRAME: material.Wireframe = Material.Wireframe; break;
						case EMF_POINTCLOUD: material.PointCloud = Material.PointCloud; break;
						case EMF_GOURAUD_SHADING: material.GouraudShading = Material.GouraudShading; break;
						case EMF_LIGHTING: material.Lighting = Material.Lighting; break;
						case EMF_ZBUFFER: material.ZBuffer = Material.ZBuffer; break;
						case EMF_ZWRITE_ENABLE: material.ZWriteEnable = Material.ZWriteEnable; break;
						case EMF_BACK_FACE_CULLING: material.BackfaceCulling = Material.BackfaceCulling; break;
						case EMF_FRONT_FACE_CULLING: material.FrontfaceCulling = Material.FrontfaceCulling; break;
						case EMF_BILINEAR_FILTER: 
							for ( int i=0; i<MATERIAL_MAX_TEXTURES; ++i)
							{
								if ( EnableLayerFlags[i] )
								{
									material.TextureLayer[i].BilinearFilter = Material.TextureLayer[i].BilinearFilter; 
								}
							}
							break;
						case EMF_TRILINEAR_FILTER: 
							for ( int i=0; i<MATERIAL_MAX_TEXTURES; ++i)
							{
								if ( EnableLayerFlags[i] )
								{
									material.TextureLayer[i].TrilinearFilter = Material.TextureLayer[i].TrilinearFilter; 
								}
							}
							break;
						case EMF_ANISOTROPIC_FILTER: 
							for ( int i=0; i<MATERIAL_MAX_TEXTURES; ++i)
							{
								if ( EnableLayerFlags[i] )
								{
									material.TextureLayer[i].AnisotropicFilter = Material.TextureLayer[i].AnisotropicFilter; 
								}
							}
							break;
						case EMF_FOG_ENABLE: material.FogEnable = Material.FogEnable; break;
						case EMF_NORMALIZE_NORMALS: material.NormalizeNormals = Material.NormalizeNormals; break;
						case EMF_TEXTURE_WRAP:
							for ( int i=0; i<MATERIAL_MAX_TEXTURES; ++i)
							{
								if ( EnableLayerFlags[i] )
								{
									material.TextureLayer[i].TextureWrapU = Material.TextureLayer[i].TextureWrapU;
									material.TextureLayer[i].TextureWrapV = Material.TextureLayer[i].TextureWrapV;
									material.TextureLayer[i].TextureWrapW = Material.TextureLayer[i].TextureWrapW;
								}
							}
							break;
						case EMF_ANTI_ALIASING: material.AntiAliasing = Material.AntiAliasing; break;
						case EMF_COLOR_MASK: material.ColorMask = Material.ColorMask; break;
						case EMF_COLOR_MATERIAL: material.ColorMaterial = Material.ColorMaterial; break;
						case EMF_USE_MIP_MAPS: material.UseMipMaps = Material.UseMipMaps; break;
						case EMF_BLEND_OPERATION: material.BlendOperation = Material.BlendOperation; break;
						case EMF_BLEND_FACTOR: material.BlendFactor = Material.BlendFactor; break;
						case EMF_POLYGON_OFFSET:
							material.PolygonOffsetDirection = Material.PolygonOffsetDirection;
							material.PolygonOffsetFactor = Material.PolygonOffsetFactor; 
							material.PolygonOffsetDepthBias = Material.PolygonOffsetDepthBias;
							material.PolygonOffsetSlopeScale = Material.PolygonOffsetSlopeScale;
							break;
						}
					}
				}
				for(int i=0; i<MATERIAL_MAX_TEXTURES; ++i )
				{
					if ( EnableLayers[i] )
					{
						material.TextureLayer[i] = Material.TextureLayer[i];
					}
					else if ( EnableTextures[i] )
					{
						material.TextureLayer[i].Texture = Material.TextureLayer[i].Texture;
					}
				}
			}
		}

	};

} // end namespace video
} // end namespace irr

#endif // __S_OVERRIDE_MATERIAL_H_INCLUDED__