// Copyright 2016 The SwiftShader Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//    http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// Texture.h: Defines the abstract Texture class and its concrete derived
// classes Texture2D and TextureCubeMap. Implements GL texture objects and
// related functionality.

#ifndef LIBGL_TEXTURE_H_
#define LIBGL_TEXTURE_H_

#include "Renderbuffer.h"
#include "common/Object.hpp"
#include "utilities.h"
#include "common/debug.h"

#define _GDI32_
#include <windows.h>
#include <GL/GL.h>
#include <GL/glext.h>

#include <vector>

namespace gl
{
class Surface;
class Config;
class Framebuffer;

enum
{
	IMPLEMENTATION_MAX_TEXTURE_LEVELS = sw::MIPMAP_LEVELS,
	IMPLEMENTATION_MAX_TEXTURE_SIZE = 1 << (IMPLEMENTATION_MAX_TEXTURE_LEVELS - 1),
	IMPLEMENTATION_MAX_CUBE_MAP_TEXTURE_SIZE = 1 << (IMPLEMENTATION_MAX_TEXTURE_LEVELS - 1),
	IMPLEMENTATION_MAX_RENDERBUFFER_SIZE = sw::OUTLINE_RESOLUTION,
};

class Texture : public NamedObject
{
public:
	explicit Texture(GLuint name);

	virtual ~Texture();

	sw::Resource *getResource() const;

	virtual void addProxyRef(const Renderbuffer *proxy) = 0;
	virtual void releaseProxy(const Renderbuffer *proxy) = 0;

	virtual GLenum getTarget() const = 0;

	bool setMinFilter(GLenum filter);
	bool setMagFilter(GLenum filter);
	bool setWrapS(GLenum wrap);
	bool setWrapT(GLenum wrap);
	bool setMaxAnisotropy(GLfloat textureMaxAnisotropy);
	bool setMaxLevel(int level);

	GLenum getMinFilter() const;
	GLenum getMagFilter() const;
	GLenum getWrapS() const;
	GLenum getWrapT() const;
	GLfloat getMaxAnisotropy() const;

	virtual GLsizei getWidth(GLenum target, GLint level) const = 0;
	virtual GLsizei getHeight(GLenum target, GLint level) const = 0;
	virtual GLenum getFormat(GLenum target, GLint level) const = 0;
	virtual GLenum getType(GLenum target, GLint level) const = 0;
	virtual sw::Format getInternalFormat(GLenum target, GLint level) const = 0;
	virtual int getLevelCount() const = 0;

	virtual bool isSamplerComplete() const = 0;
	virtual bool isCompressed(GLenum target, GLint level) const = 0;
	virtual bool isDepth(GLenum target, GLint level) const = 0;

	virtual Renderbuffer *getRenderbuffer(GLenum target) = 0;
	virtual Image *getRenderTarget(GLenum target, unsigned int level) = 0;

	virtual void generateMipmaps() = 0;
	virtual void copySubImage(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint x, GLint y, GLsizei width, GLsizei height, Framebuffer *source) = 0;

protected:
	void setImage(GLenum format, GLenum type, GLint unpackAlignment, const void *pixels, Image *image);
	void subImage(GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, GLenum type, GLint unpackAlignment, const void *pixels, Image *image);
	void setCompressedImage(GLsizei imageSize, const void *pixels, Image *image);
	void subImageCompressed(GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, GLsizei imageSize, const void *pixels, Image *image);

	bool copy(Image *source, const sw::Rect &sourceRect, GLenum destFormat, GLint xoffset, GLint yoffset, Image *dest);

	bool isMipmapFiltered() const;

	GLenum mMinFilter;
	GLenum mMagFilter;
	GLenum mWrapS;
	GLenum mWrapT;
	GLfloat mMaxAnisotropy;
	GLint mMaxLevel;

	sw::Resource *resource;
};

class Texture2D : public Texture
{
public:
	explicit Texture2D(GLuint name);

	virtual ~Texture2D();

	void addProxyRef(const Renderbuffer *proxy);
	void releaseProxy(const Renderbuffer *proxy);

	virtual GLenum getTarget() const;

	virtual GLsizei getWidth(GLenum target, GLint level) const;
	virtual GLsizei getHeight(GLenum target, GLint level) const;
	virtual GLenum getFormat(GLenum target, GLint level) const;
	virtual GLenum getType(GLenum target, GLint level) const;
	virtual sw::Format getInternalFormat(GLenum target, GLint level) const;
	virtual int getLevelCount() const;

	void setImage(GLint level, GLsizei width, GLsizei height, GLenum format, GLenum type, GLint unpackAlignment, const void *pixels);
	void setCompressedImage(GLint level, GLenum format, GLsizei width, GLsizei height, GLsizei imageSize, const void *pixels);
	void subImage(GLint level, GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, GLenum type, GLint unpackAlignment, const void *pixels);
	void subImageCompressed(GLint level, GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, GLsizei imageSize, const void *pixels);
	void copyImage(GLint level, GLenum format, GLint x, GLint y, GLsizei width, GLsizei height, Framebuffer *source);
	void copySubImage(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint x, GLint y, GLsizei width, GLsizei height, Framebuffer *source);

	void setImage(Image *image);

	virtual bool isSamplerComplete() const;
	virtual bool isCompressed(GLenum target, GLint level) const;
	virtual bool isDepth(GLenum target, GLint level) const;

	virtual void generateMipmaps();

	virtual Renderbuffer *getRenderbuffer(GLenum target);
	virtual Image *getRenderTarget(GLenum target, unsigned int level);

	Image *getImage(unsigned int level);

protected:
	bool isMipmapComplete() const;

	Image *image[IMPLEMENTATION_MAX_TEXTURE_LEVELS];

	// A specific internal reference count is kept for colorbuffer proxy references,
	// because, as the renderbuffer acting as proxy will maintain a binding pointer
	// back to this texture, there would be a circular reference if we used a binding
	// pointer here. This reference count will cause the pointer to be set to null if
	// the count drops to zero, but will not cause deletion of the Renderbuffer.
	Renderbuffer *mColorbufferProxy;
	unsigned int mProxyRefs;
};

class TextureCubeMap : public Texture
{
public:
	explicit TextureCubeMap(GLuint name);

	virtual ~TextureCubeMap();

	void addProxyRef(const Renderbuffer *proxy);
	void releaseProxy(const Renderbuffer *proxy);

	virtual GLenum getTarget() const;

	virtual GLsizei getWidth(GLenum target, GLint level) const;
	virtual GLsizei getHeight(GLenum target, GLint level) const;
	virtual GLenum getFormat(GLenum target, GLint level) const;
	virtual GLenum getType(GLenum target, GLint level) const;
	virtual sw::Format getInternalFormat(GLenum target, GLint level) const;
	virtual int getLevelCount() const;

	void setImage(GLenum target, GLint level, GLsizei width, GLsizei height, GLenum format, GLenum type, GLint unpackAlignment, const void *pixels);
	void setCompressedImage(GLenum target, GLint level, GLenum format, GLsizei width, GLsizei height, GLsizei imageSize, const void *pixels);

	void subImage(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, GLenum type, GLint unpackAlignment, const void *pixels);
	void subImageCompressed(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLsizei width, GLsizei height, GLenum format, GLsizei imageSize, const void *pixels);
	void copyImage(GLenum target, GLint level, GLenum format, GLint x, GLint y, GLsizei width, GLsizei height, Framebuffer *source);
	virtual void copySubImage(GLenum target, GLint level, GLint xoffset, GLint yoffset, GLint x, GLint y, GLsizei width, GLsizei height, Framebuffer *source);

	virtual bool isSamplerComplete() const;
	virtual bool isCompressed(GLenum target, GLint level) const;
	virtual bool isDepth(GLenum target, GLint level) const;

	virtual void generateMipmaps();

	virtual Renderbuffer *getRenderbuffer(GLenum target);
	virtual Image *getRenderTarget(GLenum target, unsigned int level);

	Image *getImage(int face, unsigned int level);

private:
	bool isCubeComplete() const;
	bool isMipmapCubeComplete() const;

	// face is one of the GL_TEXTURE_CUBE_MAP_* enumerants. Returns nullptr on failure.
	Image *getImage(GLenum face, unsigned int level);

	Image *image[6][IMPLEMENTATION_MAX_TEXTURE_LEVELS];

	// A specific internal reference count is kept for colorbuffer proxy references,
	// because, as the renderbuffer acting as proxy will maintain a binding pointer
	// back to this texture, there would be a circular reference if we used a binding
	// pointer here. This reference count will cause the pointer to be set to null if
	// the count drops to zero, but will not cause deletion of the Renderbuffer.
	Renderbuffer *mFaceProxies[6];
	unsigned int mFaceProxyRefs[6];
};

}

#endif   // LIBGL_TEXTURE_H_