// Copyright (c) 2011 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 "ppapi/shared_impl/ppb_graphics_3d_shared.h"

#include "base/logging.h"
#include "gpu/command_buffer/client/gles2_cmd_helper.h"
#include "gpu/command_buffer/client/gles2_implementation.h"
#include "ppapi/c/pp_errors.h"

namespace ppapi {

PPB_Graphics3D_Shared::PPB_Graphics3D_Shared(PP_Instance instance)
    : Resource(instance),
      transfer_buffer_id_(-1) {
}

PPB_Graphics3D_Shared::PPB_Graphics3D_Shared(const HostResource& host_resource)
    : Resource(host_resource),
      transfer_buffer_id_(-1) {
}

PPB_Graphics3D_Shared::~PPB_Graphics3D_Shared() {
  // Make sure that GLES2 implementation has already been destroyed.
  DCHECK_EQ(transfer_buffer_id_, -1);
  DCHECK(!gles2_helper_.get());
  DCHECK(!gles2_impl_.get());
}

thunk::PPB_Graphics3D_API* PPB_Graphics3D_Shared::AsPPB_Graphics3D_API() {
  return this;
}

int32_t PPB_Graphics3D_Shared::GetAttribs(int32_t* attrib_list) {
  // TODO(alokp): Implement me.
  return PP_ERROR_FAILED;
}

int32_t PPB_Graphics3D_Shared::SetAttribs(int32_t* attrib_list) {
  // TODO(alokp): Implement me.
  return PP_ERROR_FAILED;
}

int32_t PPB_Graphics3D_Shared::GetError() {
  // TODO(alokp): Implement me.
  return PP_ERROR_FAILED;
}

int32_t PPB_Graphics3D_Shared::ResizeBuffers(int32_t width, int32_t height) {
  if ((width < 0) || (height < 0))
    return PP_ERROR_BADARGUMENT;

  gles2_impl()->ResizeCHROMIUM(width, height);
  // TODO(alokp): Check if resize succeeded and return appropriate error code.
  return PP_OK;
}

int32_t PPB_Graphics3D_Shared::SwapBuffers(PP_CompletionCallback callback) {
  if (!callback.func) {
    // Blocking SwapBuffers isn't supported (since we have to be on the main
    // thread).
    return PP_ERROR_BADARGUMENT;
  }

  if (HasPendingSwap()) {
    // Already a pending SwapBuffers that hasn't returned yet.
    return PP_ERROR_INPROGRESS;
  }

  swap_callback_ = new TrackedCallback(this, callback);
  return DoSwapBuffers();
}

void* PPB_Graphics3D_Shared::MapTexSubImage2DCHROMIUM(GLenum target,
                                                      GLint level,
                                                      GLint xoffset,
                                                      GLint yoffset,
                                                      GLsizei width,
                                                      GLsizei height,
                                                      GLenum format,
                                                      GLenum type,
                                                      GLenum access) {
  return gles2_impl_->MapTexSubImage2DCHROMIUM(
      target, level, xoffset, yoffset, width, height, format, type, access);
}

void PPB_Graphics3D_Shared::UnmapTexSubImage2DCHROMIUM(const void* mem) {
  gles2_impl_->UnmapTexSubImage2DCHROMIUM(mem);
}

void PPB_Graphics3D_Shared::SwapBuffersACK(int32_t pp_error) {
  DCHECK(HasPendingSwap());
  TrackedCallback::ClearAndRun(&swap_callback_, pp_error);
}

bool PPB_Graphics3D_Shared::HasPendingSwap() const {
  return TrackedCallback::IsPending(swap_callback_);
}

bool PPB_Graphics3D_Shared::CreateGLES2Impl(int32 command_buffer_size,
                                            int32 transfer_buffer_size) {
  gpu::CommandBuffer* command_buffer = GetCommandBuffer();
  DCHECK(command_buffer);

  // Create the GLES2 helper, which writes the command buffer protocol.
  gles2_helper_.reset(new gpu::gles2::GLES2CmdHelper(command_buffer));
  if (!gles2_helper_->Initialize(command_buffer_size))
    return false;

  // Create a transfer buffer used to copy resources between the renderer
  // process and the GPU process.
  transfer_buffer_id_ =
      command_buffer->CreateTransferBuffer(transfer_buffer_size, -1);
  if (transfer_buffer_id_ < 0)
    return false;

  // Map the buffer into the renderer process's address space.
  gpu::Buffer transfer_buffer =
      command_buffer->GetTransferBuffer(transfer_buffer_id_);
  if (!transfer_buffer.ptr)
    return false;

  // Create the object exposing the OpenGL API.
  gles2_impl_.reset(new gpu::gles2::GLES2Implementation(
      gles2_helper_.get(),
      transfer_buffer.size,
      transfer_buffer.ptr,
      transfer_buffer_id_,
      false,
      true));

  return true;
}

void PPB_Graphics3D_Shared::DestroyGLES2Impl() {
  gles2_impl_.reset();

  if (transfer_buffer_id_ != -1) {
    gpu::CommandBuffer* command_buffer = GetCommandBuffer();
    DCHECK(command_buffer);
    command_buffer->DestroyTransferBuffer(transfer_buffer_id_);
    transfer_buffer_id_ = -1;
  }

  gles2_helper_.reset();
}

}  // namespace ppapi