// Copyright (c) 2008-2009 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/glue/webmediaplayer_impl.h"

#include "base/command_line.h"
#include "googleurl/src/gurl.h"
#include "media/filters/ffmpeg_audio_decoder.h"
#include "media/filters/ffmpeg_demuxer.h"
#include "media/filters/ffmpeg_video_decoder.h"
#include "media/filters/null_audio_renderer.h"
#include "webkit/api/public/WebRect.h"
#include "webkit/api/public/WebSize.h"
#include "webkit/api/public/WebURL.h"
#include "webkit/glue/media/video_renderer_impl.h"

using WebKit::WebCanvas;
using WebKit::WebRect;
using WebKit::WebSize;

namespace {

// Limits the maximum outstanding repaints posted on render thread.
// This number of 50 is a guess, it does not take too much memory on the task
// queue but gives up a pretty good latency on repaint.
const int kMaxOutstandingRepaints = 50;

}  // namespace

namespace webkit_glue {

/////////////////////////////////////////////////////////////////////////////
// WebMediaPlayerImpl::Proxy implementation

WebMediaPlayerImpl::Proxy::Proxy(MessageLoop* render_loop,
                                 WebMediaPlayerImpl* webmediaplayer)
    : render_loop_(render_loop),
      webmediaplayer_(webmediaplayer),
      outstanding_repaints_(0) {
  DCHECK(render_loop_);
  DCHECK(webmediaplayer_);
}

WebMediaPlayerImpl::Proxy::~Proxy() {
  Detach();
}

void WebMediaPlayerImpl::Proxy::Repaint() {
  AutoLock auto_lock(lock_);
  if (outstanding_repaints_ < kMaxOutstandingRepaints) {
    ++outstanding_repaints_;

    render_loop_->PostTask(FROM_HERE,
        NewRunnableMethod(this, &WebMediaPlayerImpl::Proxy::RepaintTask));
  }
}

void WebMediaPlayerImpl::Proxy::TimeChanged() {
  render_loop_->PostTask(FROM_HERE,
      NewRunnableMethod(this, &WebMediaPlayerImpl::Proxy::TimeChangedTask));
}

void WebMediaPlayerImpl::Proxy::NetworkStateChanged(
    WebKit::WebMediaPlayer::NetworkState state) {
  render_loop_->PostTask(FROM_HERE,
      NewRunnableMethod(this,
                        &WebMediaPlayerImpl::Proxy::NetworkStateChangedTask,
                        state));
}

void WebMediaPlayerImpl::Proxy::ReadyStateChanged(
    WebKit::WebMediaPlayer::ReadyState state) {
  render_loop_->PostTask(FROM_HERE,
      NewRunnableMethod(this,
                        &WebMediaPlayerImpl::Proxy::ReadyStateChangedTask,
                        state));
}

void WebMediaPlayerImpl::Proxy::RepaintTask() {
  DCHECK(MessageLoop::current() == render_loop_);
  {
    AutoLock auto_lock(lock_);
    --outstanding_repaints_;
    DCHECK_GE(outstanding_repaints_, 0);
  }
  if (webmediaplayer_)
    webmediaplayer_->Repaint();
}

void WebMediaPlayerImpl::Proxy::TimeChangedTask() {
  DCHECK(MessageLoop::current() == render_loop_);
  if (webmediaplayer_)
    webmediaplayer_->TimeChanged();
}

void WebMediaPlayerImpl::Proxy::NetworkStateChangedTask(
    WebKit::WebMediaPlayer::NetworkState state) {
  DCHECK(MessageLoop::current() == render_loop_);
  if (webmediaplayer_)
    webmediaplayer_->SetNetworkState(state);
}

void WebMediaPlayerImpl::Proxy::ReadyStateChangedTask(
    WebKit::WebMediaPlayer::ReadyState state) {
  DCHECK(MessageLoop::current() == render_loop_);
  if (webmediaplayer_)
    webmediaplayer_->SetReadyState(state);
}

void WebMediaPlayerImpl::Proxy::SetVideoRenderer(
    VideoRendererImpl* video_renderer) {
  video_renderer_ = video_renderer;
}

void WebMediaPlayerImpl::Proxy::Paint(skia::PlatformCanvas* canvas,
                                      const gfx::Rect& dest_rect) {
  DCHECK(MessageLoop::current() == render_loop_);
  if (video_renderer_) {
    video_renderer_->Paint(canvas, dest_rect);
  }
}

void WebMediaPlayerImpl::Proxy::SetSize(const gfx::Rect& rect) {
  DCHECK(MessageLoop::current() == render_loop_);
  if (video_renderer_) {
    video_renderer_->SetRect(rect);
  }
}

void WebMediaPlayerImpl::Proxy::Detach() {
  DCHECK(MessageLoop::current() == render_loop_);
  webmediaplayer_ = NULL;
  video_renderer_ = NULL;
}

void WebMediaPlayerImpl::Proxy::PipelineInitializationCallback(bool success) {
  if (success) {
    // Since we have initialized the pipeline, say we have everything.
    // TODO(hclam): change this to report the correct status. Should also post
    // a task to call to |webmediaplayer_|.
    ReadyStateChanged(WebKit::WebMediaPlayer::HaveMetadata);
    ReadyStateChanged(WebKit::WebMediaPlayer::HaveEnoughData);
    NetworkStateChanged(WebKit::WebMediaPlayer::Loaded);
  } else {
    // TODO(hclam): should use pipeline_.GetError() to determine the state
    // properly and reports error using MediaError.
    // WebKit uses FormatError to indicate an error for bogus URL or bad file.
    // Since we are at the initialization stage we can safely treat every error
    // as format error. Should post a task to call to |webmediaplayer_|.
    NetworkStateChanged(WebKit::WebMediaPlayer::FormatError);
  }
}

void WebMediaPlayerImpl::Proxy::PipelineSeekCallback(bool success) {
  if (success)
    TimeChanged();
}

/////////////////////////////////////////////////////////////////////////////
// WebMediaPlayerImpl implementation

WebMediaPlayerImpl::WebMediaPlayerImpl(WebKit::WebMediaPlayerClient* client,
                                       media::FilterFactoryCollection* factory)
    : network_state_(WebKit::WebMediaPlayer::Empty),
      ready_state_(WebKit::WebMediaPlayer::HaveNothing),
      main_loop_(NULL),
      filter_factory_(factory),
      client_(client) {
  // Saves the current message loop.
  DCHECK(!main_loop_);
  main_loop_ = MessageLoop::current();

  // Also we want to be notified of |main_loop_| destruction.
  main_loop_->AddDestructionObserver(this);

  // Creates the proxy.
  proxy_ = new Proxy(main_loop_, this);

  // Add in the default filter factories.
  filter_factory_->AddFactory(media::FFmpegDemuxer::CreateFilterFactory());
  filter_factory_->AddFactory(media::FFmpegAudioDecoder::CreateFactory());
  filter_factory_->AddFactory(media::FFmpegVideoDecoder::CreateFactory());
  filter_factory_->AddFactory(media::NullAudioRenderer::CreateFilterFactory());
  filter_factory_->AddFactory(VideoRendererImpl::CreateFactory(proxy_));
}

WebMediaPlayerImpl::~WebMediaPlayerImpl() {
  Destroy();

  // Finally tell the |main_loop_| we don't want to be notified of destruction
  // event.
  if (main_loop_) {
    main_loop_->RemoveDestructionObserver(this);
  }
}

void WebMediaPlayerImpl::load(const WebKit::WebURL& url) {
  DCHECK(MessageLoop::current() == main_loop_);
  DCHECK(proxy_);

  // Initialize the pipeline.
  SetNetworkState(WebKit::WebMediaPlayer::Loading);
  SetReadyState(WebKit::WebMediaPlayer::HaveNothing);
  pipeline_.Start(
      filter_factory_.get(),
      url.spec(),
      NewCallback(proxy_.get(),
                  &WebMediaPlayerImpl::Proxy::PipelineInitializationCallback));
}

void WebMediaPlayerImpl::cancelLoad() {
  DCHECK(MessageLoop::current() == main_loop_);
}

void WebMediaPlayerImpl::play() {
  DCHECK(MessageLoop::current() == main_loop_);

  // TODO(hclam): We should restore the previous playback rate rather than
  // having it at 1.0.
  pipeline_.SetPlaybackRate(1.0f);
}

void WebMediaPlayerImpl::pause() {
  DCHECK(MessageLoop::current() == main_loop_);

  pipeline_.SetPlaybackRate(0.0f);
}

void WebMediaPlayerImpl::seek(float seconds) {
  DCHECK(MessageLoop::current() == main_loop_);

  // Try to preserve as much accuracy as possible.
  float microseconds = seconds * base::Time::kMicrosecondsPerSecond;
  if (seconds != 0)
  pipeline_.Seek(
      base::TimeDelta::FromMicroseconds(static_cast<int64>(microseconds)),
      NewCallback(proxy_.get(),
                  &WebMediaPlayerImpl::Proxy::PipelineSeekCallback));
}

void WebMediaPlayerImpl::setEndTime(float seconds) {
  DCHECK(MessageLoop::current() == main_loop_);

  // TODO(hclam): add method call when it has been implemented.
  return;
}

void WebMediaPlayerImpl::setRate(float rate) {
  DCHECK(MessageLoop::current() == main_loop_);

  pipeline_.SetPlaybackRate(rate);
}

void WebMediaPlayerImpl::setVolume(float volume) {
  DCHECK(MessageLoop::current() == main_loop_);

  pipeline_.SetVolume(volume);
}

void WebMediaPlayerImpl::setVisible(bool visible) {
  DCHECK(MessageLoop::current() == main_loop_);

  // TODO(hclam): add appropriate method call when pipeline has it implemented.
  return;
}

bool WebMediaPlayerImpl::setAutoBuffer(bool autoBuffer) {
  DCHECK(MessageLoop::current() == main_loop_);

  return false;
}

bool WebMediaPlayerImpl::totalBytesKnown() {
  DCHECK(MessageLoop::current() == main_loop_);

  return pipeline_.GetTotalBytes() != 0;
}

bool WebMediaPlayerImpl::hasVideo() const {
  DCHECK(MessageLoop::current() == main_loop_);

  size_t width, height;
  pipeline_.GetVideoSize(&width, &height);
  return width != 0 && height != 0;
}

WebKit::WebSize WebMediaPlayerImpl::naturalSize() const {
  DCHECK(MessageLoop::current() == main_loop_);

  size_t width, height;
  pipeline_.GetVideoSize(&width, &height);
  return WebKit::WebSize(width, height);
}

bool WebMediaPlayerImpl::paused() const {
  DCHECK(MessageLoop::current() == main_loop_);

  return pipeline_.GetPlaybackRate() == 0.0f;
}

bool WebMediaPlayerImpl::seeking() const {
  DCHECK(MessageLoop::current() == main_loop_);

  return false;
}

float WebMediaPlayerImpl::duration() const {
  DCHECK(MessageLoop::current() == main_loop_);

  return static_cast<float>(pipeline_.GetDuration().InSecondsF());
}

float WebMediaPlayerImpl::currentTime() const {
  DCHECK(MessageLoop::current() == main_loop_);

  return static_cast<float>(pipeline_.GetTime().InSecondsF());
}

int WebMediaPlayerImpl::dataRate() const {
  DCHECK(MessageLoop::current() == main_loop_);

  // TODO(hclam): Add this method call if pipeline has it in the interface.
  return 0;
}

float WebMediaPlayerImpl::maxTimeBuffered() const {
  DCHECK(MessageLoop::current() == main_loop_);

  return static_cast<float>(pipeline_.GetBufferedTime().InSecondsF());
}

float WebMediaPlayerImpl::maxTimeSeekable() const {
  DCHECK(MessageLoop::current() == main_loop_);

  // TODO(scherkus): move this logic down into the pipeline.
  if (pipeline_.GetTotalBytes() == 0) {
    return 0.0f;
  }
  double total_bytes = static_cast<double>(pipeline_.GetTotalBytes());
  double buffered_bytes = static_cast<double>(pipeline_.GetBufferedBytes());
  double duration = static_cast<double>(pipeline_.GetDuration().InSecondsF());
  return static_cast<float>(duration * (buffered_bytes / total_bytes));
}

unsigned long long WebMediaPlayerImpl::bytesLoaded() const {
  DCHECK(MessageLoop::current() == main_loop_);

  return pipeline_.GetBufferedBytes();
}

unsigned long long WebMediaPlayerImpl::totalBytes() const {
  DCHECK(MessageLoop::current() == main_loop_);

  return pipeline_.GetTotalBytes();
}

void WebMediaPlayerImpl::setSize(const WebSize& size) {
  DCHECK(MessageLoop::current() == main_loop_);
  DCHECK(proxy_);

  proxy_->SetSize(gfx::Rect(0, 0, size.width, size.height));
}

void WebMediaPlayerImpl::paint(WebCanvas* canvas,
                               const WebRect& rect) {
  DCHECK(MessageLoop::current() == main_loop_);
  DCHECK(proxy_);

  proxy_->Paint(canvas, rect);
}

void WebMediaPlayerImpl::WillDestroyCurrentMessageLoop() {
  Destroy();
  main_loop_ = NULL;
}

void WebMediaPlayerImpl::Repaint() {
  DCHECK(MessageLoop::current() == main_loop_);
  GetClient()->repaint();
}

void WebMediaPlayerImpl::TimeChanged() {
  DCHECK(MessageLoop::current() == main_loop_);
  GetClient()->timeChanged();
}

void WebMediaPlayerImpl::SetNetworkState(
    WebKit::WebMediaPlayer::NetworkState state) {
  DCHECK(MessageLoop::current() == main_loop_);
  if (network_state_ != state) {
    network_state_ = state;
    GetClient()->networkStateChanged();
  }
}

void WebMediaPlayerImpl::SetReadyState(
    WebKit::WebMediaPlayer::ReadyState state) {
  DCHECK(MessageLoop::current() == main_loop_);
  if (ready_state_ != state) {
    ready_state_ = state;
    GetClient()->readyStateChanged();
  }
}

void WebMediaPlayerImpl::Destroy() {
  DCHECK(MessageLoop::current() == main_loop_);

  // Make sure to kill the pipeline so there's no more media threads running.
  // TODO(hclam): stopping the pipeline is synchronous so it might block
  // stopping for a long time.
  pipeline_.Stop();

  // And then detach the proxy, it may live on the render thread for a little
  // longer until all the tasks are finished.
  if (proxy_) {
    proxy_->Detach();
    proxy_ = NULL;
  }
}

WebKit::WebMediaPlayerClient* WebMediaPlayerImpl::GetClient() {
  DCHECK(MessageLoop::current() == main_loop_);
  DCHECK(client_);
  return client_;
}

}  // namespace webkit_glue