/*
 * OpenClonk, http://www.openclonk.org
 *
 * Copyright (c) 2001-2009, RedWolf Design GmbH, http://www.clonk.de/
 * Copyright (c) 2009-2015, The OpenClonk Team and contributors
 *
 * Distributed under the terms of the ISC license; see accompanying file
 * "COPYING" for details.
 *
 * "Clonk" is a registered trademark of Matthes Bender, used with permission.
 * See accompanying file "TRADEMARK" for details.
 *
 * To redistribute this file separately, substitute the full license texts
 * for the above references.
 */

#ifndef C4LANDSCAPE_RENDER_H
#define C4LANDSCAPE_RENDER_H

#include "C4Surface.h"
#include "C4FacetEx.h"
#include "C4Shader.h"

// Data we want to store per landscape pixel
enum C4LR_Byte {
	C4LR_Material,
	C4LR_BiasX,
	C4LR_BiasY,
	C4LR_Scaler,
	C4LR_Place,

	C4LR_ByteCount
};

// Uniform data we give the shader (constants from its viewpoint)
// Don't forget to update GetUniformName when introducing new uniforms!
enum C4LR_Uniforms
{
	C4LRU_LandscapeTex,
	C4LRU_ScalerTex,
	C4LRU_MaterialTex,
	C4LRU_LightTex,
	C4LRU_AmbientTex,

	C4LRU_Gamma,
	C4LRU_Resolution,
	C4LRU_Center,
	C4LRU_MatMapTex,
	C4LRU_MaterialDepth,
	C4LRU_MaterialSize,
	C4LRU_AmbientBrightness,
	C4LRU_AmbientTransform,

	C4LRU_Count
};

// How much data we want to store per landscape pixel
const int C4LR_BytesPerPx = 3;

// How much data we can hold per surface, how much surfaces we therefore need.
const int C4LR_BytesPerSurface = 4;
const int C4LR_SurfaceCount = (C4LR_ByteCount + C4LR_BytesPerSurface - 1) / C4LR_BytesPerSurface;

// How many mip-map levels should be used at maximum?
const int C4LR_MipMapCount = 6;

class C4Landscape; class C4TextureMap;

class C4LandscapeRender
{
public:
	C4LandscapeRender()
		: iWidth(0), iHeight(0), pTexs(NULL) { }
	virtual ~C4LandscapeRender()
		{}

protected:
	int32_t iWidth, iHeight;
	C4TextureMap *pTexs;

public:

	virtual bool ReInit(int32_t iWidth, int32_t iHeight) = 0;
	virtual bool Init(int32_t iWidth, int32_t iHeight, C4TextureMap *pTexs, C4GroupSet *pGraphics) = 0;
	virtual void Clear() = 0;

	// Returns the rectangle of pixels that must be updated on changes in the given rect
	virtual C4Rect GetAffectedRect(C4Rect Rect) = 0;

	// Updates the landscape rendering to reflect the landscape contents in
	// the given rectangle
	virtual void Update(C4Rect Rect, C4Landscape *pSource) = 0;

	virtual void Draw(const C4TargetFacet &cgo, const class C4FoWRegion *Light) = 0;
};

#ifndef USE_CONSOLE
class C4LandscapeRenderGL : public C4LandscapeRender
{
public:
	C4LandscapeRenderGL();
	~C4LandscapeRenderGL();

private:
	// surfaces
	C4Surface *Surfaces[C4LR_SurfaceCount];

	// shader
	C4Shader Shader;
	C4Shader ShaderLight;
	static const char *UniformNames[];
	GLenum hLandscapeTexCoord, hLightTexCoord;

	// 3D texture of material textures
	GLuint hMaterialTexture[C4LR_MipMapCount];
	// material texture positions in 3D texture
	std::vector<StdCopyStrBuf> MaterialTextureMap;
	// depth of material texture in layers
	int32_t iMaterialTextureDepth;
	// size of material textures (unzoomed)
	int32_t iMaterialWidth, iMaterialHeight;

	// scaler image
	C4FacetSurface fctScaler;

public:
	virtual bool ReInit(int32_t iWidth, int32_t iHeight);
	virtual bool Init(int32_t iWidth, int32_t iHeight, C4TextureMap *pMap, C4GroupSet *pGraphics);
	virtual void Clear();

	virtual C4Rect GetAffectedRect(C4Rect Rect);
	virtual void Update(C4Rect Rect, C4Landscape *pSource);

	virtual void Draw(const C4TargetFacet &cgo, const C4FoWRegion *Light);

	void RefreshShaders();

private:
	bool InitLandscapeTexture();
	bool InitMaterialTexture(C4TextureMap *pMap);
	bool LoadShader(C4GroupSet *pGraphics, C4Shader& shader, const char* name, int ssc);
	bool LoadShaders(C4GroupSet *pGraphics);
    void ClearShaders();
	bool LoadScaler(C4GroupSet *pGraphics);

	int CalculateScalerBitmask(int x, int y, C4Rect To, C4Landscape *pSource);

	int32_t LookupTextureTransition(const char *szFrom, const char *szTo);
	void AddTextureTransition(const char *szFrom, const char *szTo);
	void AddTextureAnim(const char *szTextureAnim);
	void AddTexturesFromMap(C4TextureMap *pMap);
	void BuildMatMap(uint32_t *pTex);
};
#endif

class C4LandscapeRenderClassic : public C4LandscapeRender
{
public:
	C4LandscapeRenderClassic();
	~C4LandscapeRenderClassic();

private:
	C4Surface *Surface32;

public:
	virtual bool ReInit(int32_t iWidth, int32_t iHeight);
	virtual bool Init(int32_t iWidth, int32_t iHeight, C4TextureMap *pMap, C4GroupSet *pGraphics);
	virtual void Clear();

	virtual C4Rect GetAffectedRect(C4Rect Rect);
	virtual void Update(C4Rect Rect, C4Landscape *pSource);

	virtual void Draw(const C4TargetFacet &cgo, const C4FoWRegion *Light);

};

#endif // C4LANDSCAPE_RENDER_H