//
// Copyright (c) 2002-2014 The ANGLE Project Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//

// Buffer.h: Defines the gl::Buffer class, representing storage of vertex and/or
// index data. Implements GL buffer objects and related functionality.
// [OpenGL ES 2.0.24] section 2.9 page 21.

#ifndef LIBANGLE_BUFFER_H_
#define LIBANGLE_BUFFER_H_

#include "common/PackedEnums.h"
#include "common/angleutils.h"
#include "libANGLE/Debug.h"
#include "libANGLE/Error.h"
#include "libANGLE/IndexRangeCache.h"
#include "libANGLE/RefCountObject.h"

namespace rx
{
class BufferImpl;
class GLImplFactory;
};

namespace gl
{
class Buffer;
class Context;

class BufferState final : angle::NonCopyable
{
  public:
    BufferState();
    ~BufferState();

    const std::string &getLabel();

    BufferUsage getUsage() const { return mUsage; }
    GLbitfield getAccessFlags() const { return mAccessFlags; }
    GLenum getAccess() const { return mAccess; }
    GLboolean isMapped() const { return mMapped; }
    void *getMapPointer() const { return mMapPointer; }
    GLint64 getMapOffset() const { return mMapOffset; }
    GLint64 getMapLength() const { return mMapLength; }
    GLint64 getSize() const { return mSize; }

  private:
    friend class Buffer;

    std::string mLabel;

    BufferUsage mUsage;
    GLint64 mSize;
    GLbitfield mAccessFlags;
    GLenum mAccess;
    GLboolean mMapped;
    void *mMapPointer;
    GLint64 mMapOffset;
    GLint64 mMapLength;
    int mBindingCount;
    int mTransformFeedbackIndexedBindingCount;
    int mTransformFeedbackGenericBindingCount;
};

class Buffer final : public RefCountObject, public LabeledObject
{
  public:
    Buffer(rx::GLImplFactory *factory, GLuint id);
    ~Buffer() override;
    Error onDestroy(const Context *context) override;

    void setLabel(const std::string &label) override;
    const std::string &getLabel() const override;

    Error bufferData(const Context *context,
                     BufferBinding target,
                     const void *data,
                     GLsizeiptr size,
                     BufferUsage usage);
    Error bufferSubData(const Context *context,
                        BufferBinding target,
                        const void *data,
                        GLsizeiptr size,
                        GLintptr offset);
    Error copyBufferSubData(const Context *context,
                            Buffer *source,
                            GLintptr sourceOffset,
                            GLintptr destOffset,
                            GLsizeiptr size);
    Error map(const Context *context, GLenum access);
    Error mapRange(const Context *context, GLintptr offset, GLsizeiptr length, GLbitfield access);
    Error unmap(const Context *context, GLboolean *result);

    // These are called when another operation changes Buffer data.
    void onTransformFeedback(const Context *context);
    void onPixelPack(const Context *context);

    Error getIndexRange(const gl::Context *context,
                        GLenum type,
                        size_t offset,
                        size_t count,
                        bool primitiveRestartEnabled,
                        IndexRange *outRange) const;

    BufferUsage getUsage() const { return mState.mUsage; }
    GLbitfield getAccessFlags() const { return mState.mAccessFlags; }
    GLenum getAccess() const { return mState.mAccess; }
    GLboolean isMapped() const { return mState.mMapped; }
    void *getMapPointer() const { return mState.mMapPointer; }
    GLint64 getMapOffset() const { return mState.mMapOffset; }
    GLint64 getMapLength() const { return mState.mMapLength; }
    GLint64 getSize() const { return mState.mSize; }

    rx::BufferImpl *getImplementation() const { return mImpl; }

    bool isBound() const;
    bool isBoundForTransformFeedbackAndOtherUse() const;
    void onTFBindingChanged(const Context *context, bool bound, bool indexed);
    void onNonTFBindingChanged(const Context *context, int incr) { mState.mBindingCount += incr; }

  private:
    BufferState mState;
    rx::BufferImpl *mImpl;

    mutable IndexRangeCache mIndexRangeCache;
};

}  // namespace gl

#endif  // LIBANGLE_BUFFER_H_
