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content / browser / media / system_media_controls_notifier.cc [blame]
// Copyright 2019 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "content/browser/media/system_media_controls_notifier.h"
#include <memory>
#include <utility>
#include "base/functional/bind.h"
#include "base/time/time.h"
#include "base/unguessable_token.h"
#include "build/build_config.h"
#include "components/system_media_controls/system_media_controls.h"
#include "content/public/browser/content_browser_client.h"
#include "content/public/browser/media_session_client.h"
#include "content/public/browser/media_session_service.h"
#include "content/public/common/content_client.h"
#include "mojo/public/cpp/bindings/remote.h"
#include "services/media_session/public/mojom/media_session.mojom.h"
#include "ui/gfx/image/image_skia.h"
#if BUILDFLAG(IS_WIN)
#include "ui/base/idle/idle.h"
#endif // BUILDFLAG(IS_WIN)
namespace content {
using PlaybackStatus =
system_media_controls::SystemMediaControls::PlaybackStatus;
const int kMinImageSize = 71;
const int kDesiredImageSize = 150;
#if BUILDFLAG(IS_WIN)
constexpr base::TimeDelta kScreenLockPollInterval = base::Seconds(1);
constexpr int kHideSmtcDelaySeconds = 5;
constexpr base::TimeDelta kHideSmtcDelay = base::Seconds(kHideSmtcDelaySeconds);
#endif // BUILDFLAG(IS_WIN)
constexpr base::TimeDelta kDebounceDelay = base::Milliseconds(10);
SystemMediaControlsNotifier::SystemMediaControlsNotifier(
system_media_controls::SystemMediaControls* system_media_controls,
base::UnguessableToken request_id)
: system_media_controls_(system_media_controls) {
DCHECK(system_media_controls_);
#if BUILDFLAG(IS_WIN)
lock_polling_timer_.Start(
FROM_HERE, kScreenLockPollInterval,
base::BindRepeating(&SystemMediaControlsNotifier::CheckLockState,
base::Unretained(this)));
#endif // BUILDFLAG(IS_WIN)
mojo::Remote<media_session::mojom::MediaControllerManager>
controller_manager_remote;
GetMediaSessionService().BindMediaControllerManager(
controller_manager_remote.BindNewPipeAndPassReceiver());
if (request_id == base::UnguessableToken::Null()) {
// Null ID for all scenarios where kWebAppSystemMediaControls is not
// supported. ie. Linux always, and Mac/Windows when the feature flag off.
// Create a media controller that follows the active session for this case.
controller_manager_remote->CreateActiveMediaController(
media_controller_remote_.BindNewPipeAndPassReceiver());
} else {
// Create a media controller tied to |request_id| when
// kWebAppSystemMediaControls is enabled (on Windows or macOS).
controller_manager_remote->CreateMediaControllerForSession(
media_controller_remote_.BindNewPipeAndPassReceiver(), request_id);
}
// Observe the active media controller for changes to playback state and
// supported actions.
media_controller_remote_->AddObserver(
media_controller_observer_receiver_.BindNewPipeAndPassRemote());
// Observe the active media controller for changes to provided artwork.
media_controller_remote_->ObserveImages(
media_session::mojom::MediaSessionImageType::kArtwork, kMinImageSize,
kDesiredImageSize,
media_controller_image_observer_receiver_.BindNewPipeAndPassRemote());
}
SystemMediaControlsNotifier::~SystemMediaControlsNotifier() = default;
void SystemMediaControlsNotifier::MediaSessionInfoChanged(
media_session::mojom::MediaSessionInfoPtr session_info_ptr) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
bool is_playing = false;
session_info_ptr_ = std::move(session_info_ptr);
if (session_info_ptr_) {
is_playing = session_info_ptr_->playback_state ==
media_session::mojom::MediaPlaybackState::kPlaying;
DebouncePlaybackStatusUpdate(is_playing ? PlaybackStatus::kPlaying
: PlaybackStatus::kPaused);
} else {
system_media_controls_->SetPlaybackStatus(PlaybackStatus::kStopped);
// These steps reference the Media Session Standard
// https://wicg.github.io/mediasession/#metadata
// 5.3.1 If the active media session is null, unset the media metadata
// presented to the platform, and terminate these steps.
ClearAllMetadata();
}
#if BUILDFLAG(IS_WIN)
if (screen_locked_) {
if (is_playing) {
StopHideSmtcTimer();
} else if (!hide_smtc_timer_.IsRunning()) {
StartHideSmtcTimer();
}
}
#endif // BUILDFLAG(IS_WIN)
}
void SystemMediaControlsNotifier::MediaSessionMetadataChanged(
const std::optional<media_session::MediaMetadata>& metadata) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
if (metadata.has_value()) {
// 5.3.3 Update the media metadata presented to the platform to match the
// metadata for the active media session.
DebounceMetadataUpdate(*metadata);
} else {
// 5.3.2 If the metadata of the active media session is an empty metadata,
// unset the media metadata presented to the platform.
ClearAllMetadata();
}
}
void SystemMediaControlsNotifier::MediaSessionActionsChanged(
const std::vector<media_session::mojom::MediaSessionAction>& actions) {
// SeekTo is not often supported so we will emulate "seekto" using
// "seekforward" and "seekbackward" if they exist.
bool seek_available = false;
for (const media_session::mojom::MediaSessionAction& action : actions) {
if (action == media_session::mojom::MediaSessionAction::kSeekTo ||
action == media_session::mojom::MediaSessionAction::kSeekBackward ||
action == media_session::mojom::MediaSessionAction::kSeekForward) {
seek_available = true;
break;
}
}
DebounceSetIsSeekToEnabled(seek_available);
}
void SystemMediaControlsNotifier::MediaSessionChanged(
const std::optional<base::UnguessableToken>& request_id) {
if (!request_id.has_value()) {
system_media_controls_->SetID(nullptr);
return;
}
auto string_id = request_id->ToString();
system_media_controls_->SetID(&string_id);
}
void SystemMediaControlsNotifier::MediaControllerImageChanged(
media_session::mojom::MediaSessionImageType type,
const SkBitmap& bitmap) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
DebounceIconUpdate(bitmap);
}
void SystemMediaControlsNotifier::MediaSessionPositionChanged(
const std::optional<media_session::MediaPosition>& position) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
if (position) {
DebouncePositionUpdate(*position);
} else {
ClearAllMetadata();
}
}
void SystemMediaControlsNotifier::DebouncePositionUpdate(
media_session::MediaPosition position) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
delayed_position_update_ = position;
MaybeScheduleMetadataUpdate();
}
void SystemMediaControlsNotifier::DebounceMetadataUpdate(
media_session::MediaMetadata metadata) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
delayed_metadata_update_ = metadata;
MaybeScheduleMetadataUpdate();
}
void SystemMediaControlsNotifier::DebouncePlaybackStatusUpdate(
system_media_controls::SystemMediaControls::PlaybackStatus
playback_status) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
delayed_playback_status_ = playback_status;
MaybeScheduleMetadataUpdate();
}
void SystemMediaControlsNotifier::DebounceIconUpdate(const SkBitmap& bitmap) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
delayed_icon_update_ = bitmap;
// Only update `delayed_icon_update_` once every kDebounceDelay.
if (!icon_update_timer_.IsRunning()) {
icon_update_timer_.Start(
FROM_HERE, kDebounceDelay,
base::BindOnce(&SystemMediaControlsNotifier::UpdateIcon,
base::Unretained(this)));
}
}
void SystemMediaControlsNotifier::DebounceSetIsSeekToEnabled(
bool is_seek_to_enabled) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
delayed_is_seek_to_enabled_ = is_seek_to_enabled;
// Only update `delayed_is_seek_to_enabled_` once every kDebounceDelay.
if (!actions_update_timer_.IsRunning()) {
auto update_seek_to_is_enabled = [](SystemMediaControlsNotifier* self) {
CHECK(self->delayed_is_seek_to_enabled_);
self->system_media_controls_->SetIsSeekToEnabled(
*self->delayed_is_seek_to_enabled_);
self->delayed_is_seek_to_enabled_ = std::nullopt;
};
actions_update_timer_.Start(
FROM_HERE, kDebounceDelay,
base::BindOnce(std::move(update_seek_to_is_enabled),
base::Unretained(this)));
}
}
void SystemMediaControlsNotifier::MaybeScheduleMetadataUpdate() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
if (metadata_update_timer_.IsRunning()) {
return;
}
metadata_update_timer_.Start(
FROM_HERE, kDebounceDelay,
base::BindOnce(&SystemMediaControlsNotifier::UpdateMetadata,
base::Unretained(this)));
}
void SystemMediaControlsNotifier::UpdateMetadata() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
if (delayed_position_update_) {
system_media_controls_->SetPosition(*delayed_position_update_);
delayed_position_update_ = std::nullopt;
}
if (delayed_metadata_update_) {
// If we need to hide the playing media's metadata we replace it with
// placeholder metadata.
if (session_info_ptr_ && session_info_ptr_->hide_metadata) {
MediaSessionClient* media_session_client = MediaSessionClient::Get();
CHECK(media_session_client);
system_media_controls_->SetTitle(
media_session_client->GetTitlePlaceholder());
system_media_controls_->SetArtist(
media_session_client->GetArtistPlaceholder());
system_media_controls_->SetAlbum(
media_session_client->GetAlbumPlaceholder());
// Always make sure the metadata replacement is accompanied by the
// thumbnail replacement.
system_media_controls_->SetThumbnail(
media_session_client->GetThumbnailPlaceholder());
} else {
// If no title was provided, the title of the tab will be in the title
// property.
system_media_controls_->SetTitle(delayed_metadata_update_->title);
// If no artist was provided, then the source URL will be in the artist
// property.
system_media_controls_->SetArtist(delayed_metadata_update_->artist);
system_media_controls_->SetAlbum(delayed_metadata_update_->album);
}
system_media_controls_->UpdateDisplay();
delayed_metadata_update_ = std::nullopt;
}
if (delayed_playback_status_) {
system_media_controls_->SetPlaybackStatus(*delayed_playback_status_);
delayed_playback_status_ = std::nullopt;
}
}
void SystemMediaControlsNotifier::UpdateIcon() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
CHECK(delayed_icon_update_);
// If we need to hide the media metadata we replace the playing media's image
// with a placeholder.
if (session_info_ptr_ && session_info_ptr_->hide_metadata) {
MediaSessionClient* media_session_client = MediaSessionClient::Get();
CHECK(media_session_client);
system_media_controls_->SetThumbnail(
media_session_client->GetThumbnailPlaceholder());
} else if (!delayed_icon_update_->empty()) {
// 5.3.4.4.3 If the image format is supported, use the image as the
// artwork for display in the platform UI. Otherwise the fetch image
// algorithm fails and terminates.
system_media_controls_->SetThumbnail(*delayed_icon_update_);
} else {
// 5.3.4.2 If metadata's artwork is empty, terminate these steps.
// If no images are fetched in the fetch image algorithm, the user agent
// may have fallback behavior such as displaying a default image as
// artwork. We display the application icon if no artwork is provided.
std::optional<gfx::ImageSkia> icon =
GetContentClient()->browser()->GetProductLogo();
if (icon.has_value()) {
system_media_controls_->SetThumbnail(*icon->bitmap());
} else {
system_media_controls_->ClearThumbnail();
}
}
delayed_icon_update_ = std::nullopt;
}
void SystemMediaControlsNotifier::ClearAllMetadata() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
metadata_update_timer_.Stop();
delayed_position_update_ = std::nullopt;
delayed_metadata_update_ = std::nullopt;
delayed_playback_status_ = std::nullopt;
system_media_controls_->ClearMetadata();
}
#if BUILDFLAG(IS_WIN)
void SystemMediaControlsNotifier::CheckLockState() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
bool new_state = ui::CheckIdleStateIsLocked();
if (screen_locked_ == new_state)
return;
screen_locked_ = new_state;
if (screen_locked_)
OnScreenLocked();
else
OnScreenUnlocked();
}
void SystemMediaControlsNotifier::OnScreenLocked() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
// If media is currently playing, don't hide the SMTC.
if (session_info_ptr_ &&
session_info_ptr_->playback_state ==
media_session::mojom::MediaPlaybackState::kPlaying) {
return;
}
// Otherwise, hide them.
system_media_controls_->SetEnabled(false);
}
void SystemMediaControlsNotifier::OnScreenUnlocked() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
StopHideSmtcTimer();
system_media_controls_->SetEnabled(true);
}
void SystemMediaControlsNotifier::StartHideSmtcTimer() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
hide_smtc_timer_.Start(
FROM_HERE, kHideSmtcDelay,
base::BindOnce(&SystemMediaControlsNotifier::HideSmtcTimerFired,
base::Unretained(this)));
}
void SystemMediaControlsNotifier::StopHideSmtcTimer() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
hide_smtc_timer_.Stop();
}
void SystemMediaControlsNotifier::HideSmtcTimerFired() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
system_media_controls_->SetEnabled(false);
}
#endif // BUILDFLAG(IS_WIN)
} // namespace content