// 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 "webkit/plugins/ppapi/ppb_video_decoder_impl.h"

#include <string>

#include "base/logging.h"
#include "base/message_loop.h"
#include "gpu/command_buffer/client/gles2_implementation.h"
#include "media/video/picture.h"
#include "ppapi/c/dev/pp_video_dev.h"
#include "ppapi/c/dev/ppb_video_decoder_dev.h"
#include "ppapi/c/dev/ppp_video_decoder_dev.h"
#include "ppapi/c/pp_completion_callback.h"
#include "ppapi/c/pp_errors.h"
#include "ppapi/thunk/enter.h"
#include "webkit/plugins/ppapi/common.h"
#include "webkit/plugins/ppapi/plugin_module.h"
#include "webkit/plugins/ppapi/ppapi_plugin_instance.h"
#include "webkit/plugins/ppapi/ppb_buffer_impl.h"
#include "webkit/plugins/ppapi/ppb_context_3d_impl.h"
#include "webkit/plugins/ppapi/resource_tracker.h"
#include "webkit/plugins/ppapi/var.h"

using ppapi::thunk::EnterResourceNoLock;
using ppapi::thunk::PPB_Buffer_API;
using ppapi::thunk::PPB_Context3D_API;
using ppapi::thunk::PPB_VideoDecoder_API;

namespace webkit {
namespace ppapi {

PPB_VideoDecoder_Impl::PPB_VideoDecoder_Impl(PluginInstance* instance)
    : Resource(instance),
      callback_factory_(ALLOW_THIS_IN_INITIALIZER_LIST(this)),
      context3d_id_(0),
      flush_callback_(PP_BlockUntilComplete()),
      reset_callback_(PP_BlockUntilComplete()),
      gles2_impl_(NULL) {
  ppp_videodecoder_ =
      static_cast<const PPP_VideoDecoder_Dev*>(instance->module()->
          GetPluginInterface(PPP_VIDEODECODER_DEV_INTERFACE));
}

PPB_VideoDecoder_Impl::~PPB_VideoDecoder_Impl() {
}

PPB_VideoDecoder_API* PPB_VideoDecoder_Impl::AsPPB_VideoDecoder_API() {
  return this;
}

// static
PP_Resource PPB_VideoDecoder_Impl::Create(PluginInstance* instance,
                                          PP_Resource context3d_id,
                                          const PP_VideoConfigElement* config) {
  scoped_refptr<PPB_VideoDecoder_Impl> decoder(
      new PPB_VideoDecoder_Impl(instance));
  if (decoder->Init(context3d_id, config))
    return decoder->GetReference();
  return 0;
}

bool PPB_VideoDecoder_Impl::Init(PP_Resource context3d_id,
                                 const PP_VideoConfigElement* config) {
  if (!instance() || !context3d_id || !config)
    return false;

  EnterResourceNoLock<PPB_Context3D_API> enter(context3d_id, true);
  if (enter.failed())
    return false;
  PPB_Context3D_Impl* context3d =
      static_cast<PPB_Context3D_Impl*>(enter.object());

  context3d_id_ = context3d_id;
  ResourceTracker::Get()->AddRefResource(context3d_id_);

  int command_buffer_route_id =
      context3d->platform_context()->GetCommandBufferRouteId();
  if (command_buffer_route_id == 0)
    return false;
  platform_video_decoder_ = instance()->delegate()->CreateVideoDecoder(
      this, command_buffer_route_id);

  gles2_impl_ = context3d->gles2_impl();

  if (!platform_video_decoder_)
    return false;

  std::vector<uint32> copied;
  // TODO(fischman,vrk): this is completely broken in that it fails to account
  // for the semantic distinction between keys and values; it is certainly
  // possible for a value to show up as 0, and that shouldn't terminate the
  // config vector.  Only a *key* of 0 should do so.
  // TODO(vrk): This is assuming PP_VideoAttributeDictionary and
  // VideoAttributeKey have identical enum values. There is no compiler
  // assert to guarantee this. We either need to add such asserts or
  // merge PP_VideoAttributeDictionary and VideoAttributeKey.
  for (const PP_VideoConfigElement* current = config;
       *current != PP_VIDEOATTR_DICTIONARY_TERMINATOR; ++current) {
    copied.push_back(static_cast<uint32>(*current));
  }

  FlushCommandBuffer();
  return platform_video_decoder_->Initialize(copied);
}

int32_t PPB_VideoDecoder_Impl::Decode(
    const PP_VideoBitstreamBuffer_Dev* bitstream_buffer,
    PP_CompletionCallback callback) {
  if (!platform_video_decoder_)
    return PP_ERROR_BADRESOURCE;

  EnterResourceNoLock<PPB_Buffer_API> enter(bitstream_buffer->data, true);
  if (enter.failed())
    return PP_ERROR_FAILED;

  PPB_Buffer_Impl* buffer = static_cast<PPB_Buffer_Impl*>(enter.object());
  media::BitstreamBuffer decode_buffer(bitstream_buffer->id,
                                       buffer->shared_memory()->handle(),
                                       static_cast<size_t>(buffer->size()));
  CHECK(bitstream_buffer_callbacks_.insert(std::make_pair(
      bitstream_buffer->id, callback)).second);

  FlushCommandBuffer();
  platform_video_decoder_->Decode(decode_buffer);
  return PP_OK_COMPLETIONPENDING;
}

void PPB_VideoDecoder_Impl::AssignPictureBuffers(
    uint32_t no_of_buffers,
    const PP_PictureBuffer_Dev* buffers) {
  if (!platform_video_decoder_)
    return;

  std::vector<media::PictureBuffer> wrapped_buffers;
  for (uint32 i = 0; i < no_of_buffers; i++) {
    PP_PictureBuffer_Dev in_buf = buffers[i];
    media::PictureBuffer buffer(
        in_buf.id,
        gfx::Size(in_buf.size.width, in_buf.size.height),
        in_buf.texture_id);
    wrapped_buffers.push_back(buffer);
  }

  FlushCommandBuffer();
  platform_video_decoder_->AssignPictureBuffers(wrapped_buffers);
}

void PPB_VideoDecoder_Impl::ReusePictureBuffer(int32_t picture_buffer_id) {
  if (!platform_video_decoder_)
    return;

  FlushCommandBuffer();
  platform_video_decoder_->ReusePictureBuffer(picture_buffer_id);
}

int32_t PPB_VideoDecoder_Impl::Flush(PP_CompletionCallback callback) {
  if (!platform_video_decoder_)
    return PP_ERROR_BADRESOURCE;

  // Store the callback to be called when Flush() is done.
  // TODO(fischman,vrk): consider implications of already-outstanding callback.
  flush_callback_ = callback;

  FlushCommandBuffer();
  platform_video_decoder_->Flush();
  return PP_OK_COMPLETIONPENDING;
}

int32_t PPB_VideoDecoder_Impl::Reset(PP_CompletionCallback callback) {
  if (!platform_video_decoder_)
    return PP_ERROR_BADRESOURCE;

  // Store the callback to be called when Reset() is done.
  // TODO(fischman,vrk): consider implications of already-outstanding callback.
  reset_callback_ = callback;

  FlushCommandBuffer();
  platform_video_decoder_->Reset();
  return PP_OK_COMPLETIONPENDING;
}

void PPB_VideoDecoder_Impl::Destroy() {
  if (!platform_video_decoder_)
    return;

  FlushCommandBuffer();
  platform_video_decoder_->Destroy();
  gles2_impl_ = NULL;
  if (context3d_id_)
    ResourceTracker::Get()->UnrefResource(context3d_id_);
  platform_video_decoder_ = NULL;
  ppp_videodecoder_ = NULL;
}

void PPB_VideoDecoder_Impl::ProvidePictureBuffers(
    uint32 requested_num_of_buffers, const gfx::Size& dimensions) {
  if (!ppp_videodecoder_)
    return;

  PP_Size out_dim = PP_MakeSize(dimensions.width(), dimensions.height());
  ScopedResourceId resource(this);
  ppp_videodecoder_->ProvidePictureBuffers(
      instance()->pp_instance(), resource.id, requested_num_of_buffers,
      out_dim);
}

void PPB_VideoDecoder_Impl::PictureReady(const media::Picture& picture) {
  if (!ppp_videodecoder_)
    return;

  PP_Picture_Dev output;
  output.picture_buffer_id = picture.picture_buffer_id();
  output.bitstream_buffer_id = picture.bitstream_buffer_id();
  ScopedResourceId resource(this);
  ppp_videodecoder_->PictureReady(
      instance()->pp_instance(), resource.id, output);
}

void PPB_VideoDecoder_Impl::DismissPictureBuffer(int32 picture_buffer_id) {
  if (!ppp_videodecoder_)
    return;

  ScopedResourceId resource(this);
  ppp_videodecoder_->DismissPictureBuffer(
      instance()->pp_instance(), resource.id, picture_buffer_id);
}

void PPB_VideoDecoder_Impl::NotifyEndOfStream() {
  if (!ppp_videodecoder_)
    return;

  ScopedResourceId resource(this);
  ppp_videodecoder_->EndOfStream(instance()->pp_instance(), resource.id);
}

void PPB_VideoDecoder_Impl::NotifyError(
    media::VideoDecodeAccelerator::Error error) {
  if (!ppp_videodecoder_)
    return;

  ScopedResourceId resource(this);
  // TODO(vrk): This is assuming VideoDecodeAccelerator::Error and
  // PP_VideoDecodeError_Dev have identical enum values. There is no compiler
  // assert to guarantee this. We either need to add such asserts or
  // merge these two enums.
  ppp_videodecoder_->NotifyError(instance()->pp_instance(), resource.id,
                                 static_cast<PP_VideoDecodeError_Dev>(error));
}

void PPB_VideoDecoder_Impl::NotifyResetDone() {
  if (reset_callback_.func == NULL)
    return;

  // Call the callback that was stored to be called when Reset is done.
  PP_RunAndClearCompletionCallback(&reset_callback_, PP_OK);
}

void PPB_VideoDecoder_Impl::NotifyEndOfBitstreamBuffer(
    int32 bitstream_buffer_id) {
  CallbackById::iterator it =
      bitstream_buffer_callbacks_.find(bitstream_buffer_id);
  DCHECK(it != bitstream_buffer_callbacks_.end());
  PP_CompletionCallback cc = it->second;
  bitstream_buffer_callbacks_.erase(it);
  PP_RunCompletionCallback(&cc, PP_OK);
}

void PPB_VideoDecoder_Impl::NotifyFlushDone() {
  if (flush_callback_.func == NULL)
    return;

  // Call the callback that was stored to be called when Flush is done.
  PP_RunAndClearCompletionCallback(&flush_callback_, PP_OK);
}

void PPB_VideoDecoder_Impl::NotifyInitializeDone() {
  NOTREACHED() << "PlatformVideoDecoder::Initialize() is synchronous!";
}

void PPB_VideoDecoder_Impl::FlushCommandBuffer() {
  // For the out-of-process case, |gles2_impl_| will be NULL in the renderer
  // process. The VideoDecoder_Proxy is charged with the responsibility of
  // doing this Flush() in the analogous places in the plugin process.
  if (gles2_impl_)
    gles2_impl_->Flush();
}

}  // namespace ppapi
}  // namespace webkit