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

#include "cc/test/test_gpu_memory_buffer_manager.h"

#include "base/logging.h"
#include "ui/gfx/gpu_memory_buffer.h"

namespace cc {
namespace {

size_t StrideInBytes(size_t width, gfx::GpuMemoryBuffer::Format format) {
  switch (format) {
    case gfx::GpuMemoryBuffer::ATCIA:
    case gfx::GpuMemoryBuffer::DXT5:
      return width;
    case gfx::GpuMemoryBuffer::ATC:
    case gfx::GpuMemoryBuffer::DXT1:
    case gfx::GpuMemoryBuffer::ETC1:
      DCHECK_EQ(width % 2, 0U);
      return width / 2;
    case gfx::GpuMemoryBuffer::RGBA_8888:
    case gfx::GpuMemoryBuffer::RGBX_8888:
    case gfx::GpuMemoryBuffer::BGRA_8888:
      return width * 4;
  }

  NOTREACHED();
  return 0;
}

class GpuMemoryBufferImpl : public gfx::GpuMemoryBuffer {
 public:
  GpuMemoryBufferImpl(const gfx::Size& size,
                      Format format,
                      scoped_ptr<base::SharedMemory> shared_memory)
      : size_(size),
        format_(format),
        shared_memory_(shared_memory.Pass()),
        mapped_(false) {}

  // Overridden from gfx::GpuMemoryBuffer:
  void* Map() override {
    DCHECK(!mapped_);
    if (!shared_memory_->Map(StrideInBytes(size_.width(), format_) *
                             size_.height()))
      return NULL;
    mapped_ = true;
    return shared_memory_->memory();
  }
  void Unmap() override {
    DCHECK(mapped_);
    shared_memory_->Unmap();
    mapped_ = false;
  }
  bool IsMapped() const override { return mapped_; }
  Format GetFormat() const override { return format_; }
  uint32 GetStride() const override {
    return StrideInBytes(size_.width(), format_);
  }
  gfx::GpuMemoryBufferHandle GetHandle() const override {
    gfx::GpuMemoryBufferHandle handle;
    handle.type = gfx::SHARED_MEMORY_BUFFER;
    handle.handle = shared_memory_->handle();
    return handle;
  }
  ClientBuffer AsClientBuffer() override {
    return reinterpret_cast<ClientBuffer>(this);
  }

 private:
  const gfx::Size size_;
  gfx::GpuMemoryBuffer::Format format_;
  scoped_ptr<base::SharedMemory> shared_memory_;
  bool mapped_;
};

}  // namespace

TestGpuMemoryBufferManager::TestGpuMemoryBufferManager() {
}

TestGpuMemoryBufferManager::~TestGpuMemoryBufferManager() {
}

scoped_ptr<gfx::GpuMemoryBuffer>
TestGpuMemoryBufferManager::AllocateGpuMemoryBuffer(
    const gfx::Size& size,
    gfx::GpuMemoryBuffer::Format format,
    gfx::GpuMemoryBuffer::Usage usage) {
  scoped_ptr<base::SharedMemory> shared_memory(new base::SharedMemory);
  if (!shared_memory->CreateAnonymous(StrideInBytes(size.width(), format) *
                                      size.height()))
    return nullptr;
  return make_scoped_ptr<gfx::GpuMemoryBuffer>(
      new GpuMemoryBufferImpl(size, format, shared_memory.Pass()));
}

gfx::GpuMemoryBuffer*
TestGpuMemoryBufferManager::GpuMemoryBufferFromClientBuffer(
    ClientBuffer buffer) {
  return reinterpret_cast<gfx::GpuMemoryBuffer*>(buffer);
}

void TestGpuMemoryBufferManager::SetDestructionSyncPoint(
    gfx::GpuMemoryBuffer* buffer,
    uint32 sync_point) {
}

}  // namespace cc