Add scrobbler with support for Last.fm, Libre.fm and ListenBrainz

src/scrobbler/audioscrobbler.cpp

@@ -0,0 +1,173 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include <algorithm>
+
+#include <QtGlobal>
+#include <QDesktopServices>
+#include <QUrlQuery>
+#include <QCryptographicHash>
+#include <QMenu>
+#include <QMessageBox>
+#include <QSettings>
+#include <QNetworkRequest>
+#include <QNetworkReply>
+#include <QJsonParseError>
+#include <QJsonDocument>
+#include <QJsonObject>
+#include <QJsonArray>
+#include <QJsonValue>
+
+#include "core/application.h"
+#include "core/closure.h"
+#include "core/logging.h"
+#include "core/network.h"
+#include "core/player.h"
+#include "core/song.h"
+#include "core/taskmanager.h"
+#include "core/iconloader.h"
+#include "settings/settingsdialog.h"
+#include "settings/scrobblersettingspage.h"
+
+#include "audioscrobbler.h"
+#include "scrobblerservices.h"
+#include "scrobblerservice.h"
+#include "lastfmscrobbler.h"
+#include "librefmscrobbler.h"
+#include "listenbrainzscrobbler.h"
+
+AudioScrobbler::AudioScrobbler(Application *app, QObject *parent) :
+  QObject(parent),
+  app_(app),
+  scrobbler_services_(new ScrobblerServices(this)),
+  enabled_(false),
+  offline_(false),
+  scrobble_button_(false) {
+
+  scrobbler_services_->AddService(new LastFMScrobbler(app_, scrobbler_services_));
+  scrobbler_services_->AddService(new LibreFMScrobbler(app_, scrobbler_services_));
+  scrobbler_services_->AddService(new ListenBrainzScrobbler(app_, scrobbler_services_));
+
+  ReloadSettings();
+
+}
+
+AudioScrobbler::~AudioScrobbler() {}
+
+void AudioScrobbler::ReloadSettings() {
+
+  QSettings s;
+  s.beginGroup(ScrobblerSettingsPage::kSettingsGroup);
+  enabled_ = s.value("enabled", false).toBool();
+  offline_ = s.value("offline", false).toBool();
+  scrobble_button_ = s.value("scrobble_button", false).toBool();
+  s.endGroup();
+
+  emit ScrobblingEnabledChanged(enabled_);
+  emit ScrobbleButtonVisibilityChanged(scrobble_button_);
+
+  for (ScrobblerService *service : scrobbler_services_->List()) {
+    service->ReloadSettings();
+  }
+
+}
+
+void AudioScrobbler::ToggleScrobbling() {
+
+  bool enabled_old_ = enabled_;
+  enabled_ = !enabled_;
+
+  QSettings s;
+  s.beginGroup(ScrobblerSettingsPage::kSettingsGroup);
+  s.setValue("enabled", enabled_);
+  s.endGroup();
+
+  if (enabled_ != enabled_old_) emit ScrobblingEnabledChanged(enabled_);
+  if (enabled_ && !offline_) { Submit(); }
+
+}
+
+void AudioScrobbler::ToggleOffline() {
+
+  bool offline_old_ = offline_;
+  offline_ = !offline_;
+
+  QSettings s;
+  s.beginGroup(ScrobblerSettingsPage::kSettingsGroup);
+  s.setValue("offline", offline_);
+  s.endGroup();
+
+  if (offline_ != offline_old_) { emit ScrobblingOfflineChanged(offline_); }
+  if (enabled_ && !offline_) { Submit(); }
+
+}
+
+void AudioScrobbler::ShowConfig() {
+  app_->OpenSettingsDialogAtPage(SettingsDialog::Page_Scrobbler);
+}
+
+void AudioScrobbler::UpdateNowPlaying(const Song &song) {
+  qLog(Debug) << "Sending now playing for song" << song.title();
+  for (ScrobblerService *service : scrobbler_services_->List()) {
+    if (!service->IsEnabled()) continue;
+    service->UpdateNowPlaying(song);
+  }
+}
+
+void AudioScrobbler::Scrobble(const Song &song, const int scrobble_point) {
+  qLog(Debug) << "Scrobbling song" << QString("") + song.title() + QString("") << "at" << scrobble_point;
+  for (ScrobblerService *service : scrobbler_services_->List()) {
+    if (!service->IsEnabled()) continue;
+    service->Scrobble(song);
+  }
+}
+
+void AudioScrobbler::Love(const Song &song) {
+  for (ScrobblerService *service : scrobbler_services_->List()) {
+    if (!service->IsEnabled() || !service->IsAuthenticated()) continue;
+    service->Love(song);
+  }
+}
+
+void AudioScrobbler::Submit() {
+  for (ScrobblerService *service : scrobbler_services_->List()) {
+    if (!service->IsEnabled() || !service->IsAuthenticated() || service->IsSubmitted()) continue;
+    service->Submitted();
+    DoInAMinuteOrSo(service, SLOT(Submit()));
+  }
+}
+
+void AudioScrobbler::WriteCache() {
+  for (ScrobblerService *service : scrobbler_services_->List()) {
+    if (!service->IsEnabled()) continue;
+    service->WriteCache();
+  }
+}
+
+void AudioScrobbler::ConnectError() {
+  for (ScrobblerService *service : scrobbler_services_->List()) {
+    connect(service, SIGNAL(ErrorMessage(QString)), SLOT(ErrorReceived(QString)));
+  }
+}
+
+void AudioScrobbler::ErrorReceived(QString error) {
+  emit ErrorMessage(error);
+}

src/scrobbler/audioscrobbler.h

@@ -0,0 +1,88 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef AUDIOSCROBBLER_H
+#define AUDIOSCROBBLER_H
+
+#include "config.h"
+
+#include <memory>
+
+#include <QtGlobal>
+#include <QObject>
+#include <QString>
+
+#include "scrobblerservices.h"
+
+class Application;
+class Song;
+class NetworkAccessManager;
+class ScrobblerService;
+
+class AudioScrobbler : public QObject {
+  Q_OBJECT
+
+ public:
+  explicit AudioScrobbler(Application *app, QObject *parent = nullptr);
+  ~AudioScrobbler();
+
+  void ReloadSettings();
+
+  bool IsEnabled() const { return enabled_; }
+  bool IsOffline() const { return offline_; }
+  bool ScrobbleButton() const { return scrobble_button_; }
+
+  void UpdateNowPlaying(const Song &song);
+  void Scrobble(const Song &song, const int scrobble_point);
+  void Love(const Song &song);
+  void ShowConfig();
+  void ConnectError();
+
+  ScrobblerService *ServiceByName(const QString &name) const { return scrobbler_services_->ServiceByName(name); }
+
+  template <typename T>
+  T *Service() {
+    return static_cast<T*>(this->ServiceByName(T::kName));
+  }
+
+ public slots:
+  void ToggleScrobbling();
+  void ToggleOffline();
+  void Submit();
+  void WriteCache();
+  void ErrorReceived(QString);
+
+ signals:
+  void ErrorMessage(QString);
+  void ScrobblingEnabledChanged(bool value);
+  void ScrobblingOfflineChanged(bool value);
+  void ScrobbleButtonVisibilityChanged(bool value);
+
+ private:
+
+  Application *app_;
+  ScrobblerServices *scrobbler_services_;
+
+  bool enabled_;
+  bool offline_;
+  bool scrobble_button_;
+
+};
+
+#endif  // AUDIOSCROBBLER_H

src/scrobbler/lastfmscrobbler.cpp

@@ -0,0 +1,82 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include <algorithm>
+
+#include <QtGlobal>
+#include <QDesktopServices>
+#include <QVariant>
+#include <QByteArray>
+#include <QString>
+#include <QUrl>
+#include <QUrlQuery>
+#include <QDateTime>
+#include <QCryptographicHash>
+#include <QMenu>
+#include <QMessageBox>
+#include <QSettings>
+#include <QNetworkRequest>
+#include <QNetworkReply>
+#include <QJsonParseError>
+#include <QJsonDocument>
+#include <QJsonObject>
+#include <QJsonArray>
+#include <QJsonValue>
+
+#include "core/application.h"
+#include "core/player.h"
+#include "core/closure.h"
+#include "core/network.h"
+#include "core/song.h"
+#include "core/timeconstants.h"
+#include "core/logging.h"
+#include "internet/localredirectserver.h"
+#include "settings/settingsdialog.h"
+#include "settings/scrobblersettingspage.h"
+
+#include "audioscrobbler.h"
+#include "scrobblerservices.h"
+#include "scrobblercache.h"
+#include "scrobblingapi20.h"
+#include "lastfmscrobbler.h"
+
+const char *LastFMScrobbler::kName = "Last.fm";
+const char *LastFMScrobbler::kSettingsGroup = "LastFM";
+const char *LastFMScrobbler::kAuthUrl = "https://www.last.fm/api/auth/";
+const char *LastFMScrobbler::kApiUrl = "https://ws.audioscrobbler.com/2.0/";
+const char *LastFMScrobbler::kCacheFile = "lastfmscrobbler.cache";
+
+LastFMScrobbler::LastFMScrobbler(Application *app, QObject *parent) : ScrobblingAPI20(kName, kSettingsGroup, kAuthUrl, kApiUrl, true, app, parent),
+  auth_url_(kAuthUrl),
+  api_url_(kApiUrl),
+  app_(app),
+  network_(new NetworkAccessManager(this)),
+  cache_(new ScrobblerCache(kCacheFile, this)),
+  enabled_(false),
+  subscriber_(false),
+  submitted_(false) {
+
+  ReloadSettings();
+  LoadSession();
+
+}
+
+LastFMScrobbler::~LastFMScrobbler() {}

src/scrobbler/lastfmscrobbler.h

@@ -0,0 +1,82 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef LASTFMSCROBBLER_H
+#define LASTFMSCROBBLER_H
+
+#include "config.h"
+
+#include <memory>
+
+#include <QtGlobal>
+#include <QObject>
+#include <QNetworkReply>
+#include <QPair>
+#include <QList>
+#include <QVariant>
+#include <QByteArray>
+#include <QString>
+#include <QJsonObject>
+
+#include "core/song.h"
+#include "scrobblerservice.h"
+#include "scrobblingapi20.h"
+
+class Application;
+class NetworkAccessManager;
+class LocalRedirectServer;
+class ScrobblerCache;
+
+class LastFMScrobbler : public ScrobblingAPI20 {
+  Q_OBJECT
+
+ public:
+  explicit LastFMScrobbler(Application *app, QObject *parent = nullptr);
+  ~LastFMScrobbler();
+
+  static const char *kName;
+  static const char *kSettingsGroup;
+
+  NetworkAccessManager *network() { return network_; }
+  ScrobblerCache *cache() { return cache_; }
+
+ private:
+  static const char *kAuthUrl;
+  static const char *kApiUrl;
+  static const char *kCacheFile;
+
+  QString settings_group_;
+  QString auth_url_;
+  QString api_url_;
+  QString api_key_;
+  QString secret_;
+  Application *app_;
+  NetworkAccessManager *network_;
+  ScrobblerCache *cache_;
+  bool enabled_;
+  bool subscriber_;
+  QString username_;
+  QString session_key_;
+  bool submitted_;
+  Song song_playing_;
+  quint64 timestamp_;
+
+};
+
+#endif  // LASTFMSCROBBLER_H

src/scrobbler/librefmscrobbler.cpp

@@ -0,0 +1,82 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include <algorithm>
+
+#include <QtGlobal>
+#include <QDesktopServices>
+#include <QVariant>
+#include <QByteArray>
+#include <QString>
+#include <QUrl>
+#include <QUrlQuery>
+#include <QDateTime>
+#include <QCryptographicHash>
+#include <QMenu>
+#include <QMessageBox>
+#include <QSettings>
+#include <QNetworkRequest>
+#include <QNetworkReply>
+#include <QJsonParseError>
+#include <QJsonDocument>
+#include <QJsonObject>
+#include <QJsonArray>
+#include <QJsonValue>
+
+#include "core/application.h"
+#include "core/player.h"
+#include "core/closure.h"
+#include "core/network.h"
+#include "core/song.h"
+#include "core/timeconstants.h"
+#include "core/logging.h"
+#include "internet/localredirectserver.h"
+#include "settings/settingsdialog.h"
+#include "settings/scrobblersettingspage.h"
+
+#include "audioscrobbler.h"
+#include "scrobblerservices.h"
+#include "scrobblercache.h"
+#include "scrobblingapi20.h"
+#include "librefmscrobbler.h"
+
+const char *LibreFMScrobbler::kName = "Libre.fm";
+const char *LibreFMScrobbler::kSettingsGroup = "LibreFM";
+const char *LibreFMScrobbler::kAuthUrl = "https://www.libre.fm/api/auth/";
+const char *LibreFMScrobbler::kApiUrl = "https://libre.fm/2.0/";
+const char *LibreFMScrobbler::kCacheFile = "librefmscrobbler.cache";
+
+LibreFMScrobbler::LibreFMScrobbler(Application *app, QObject *parent) : ScrobblingAPI20(kName, kSettingsGroup, kAuthUrl, kApiUrl, false, app, parent),
+  auth_url_(kAuthUrl),
+  api_url_(kApiUrl),
+  app_(app),
+  network_(new NetworkAccessManager(this)),
+  cache_(new ScrobblerCache(kCacheFile, this)),
+  enabled_(false),
+  subscriber_(false),
+  submitted_(false) {
+
+  ReloadSettings();
+  LoadSession();
+
+}
+
+LibreFMScrobbler::~LibreFMScrobbler() {}

src/scrobbler/librefmscrobbler.h

@@ -0,0 +1,82 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef LIBREFMSCROBBLER_H
+#define LIBREFMSCROBBLER_H
+
+#include "config.h"
+
+#include <memory>
+
+#include <QtGlobal>
+#include <QObject>
+#include <QNetworkReply>
+#include <QPair>
+#include <QList>
+#include <QVariant>
+#include <QByteArray>
+#include <QString>
+#include <QJsonObject>
+
+#include "core/song.h"
+#include "scrobblerservice.h"
+#include "scrobblingapi20.h"
+
+class Application;
+class NetworkAccessManager;
+class LocalRedirectServer;
+class ScrobblerCache;
+
+class LibreFMScrobbler : public ScrobblingAPI20 {
+  Q_OBJECT
+
+ public:
+  explicit LibreFMScrobbler(Application *app, QObject *parent = nullptr);
+  ~LibreFMScrobbler();
+
+  static const char *kName;
+  static const char *kSettingsGroup;
+
+  NetworkAccessManager *network() { return network_; }
+  ScrobblerCache *cache() { return cache_; }
+
+ private:
+  static const char *kAuthUrl;
+  static const char *kApiUrl;
+  static const char *kCacheFile;
+
+  QString settings_group_;
+  QString auth_url_;
+  QString api_url_;
+  QString api_key_;
+  QString secret_;
+  Application *app_;
+  NetworkAccessManager *network_;
+  ScrobblerCache *cache_;
+  bool enabled_;
+  bool subscriber_;
+  QString username_;
+  QString session_key_;
+  bool submitted_;
+  Song song_playing_;
+  quint64 timestamp_;
+
+};
+
+#endif  // LIBREFMSCROBBLER_H

src/scrobbler/listenbrainzscrobbler.cpp

@@ -0,0 +1,482 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include <algorithm>
+
+#include <QtGlobal>
+#include <QDesktopServices>
+#include <QVariant>
+#include <QByteArray>
+#include <QString>
+#include <QUrl>
+#include <QUrlQuery>
+#include <QDateTime>
+#include <QCryptographicHash>
+#include <QMenu>
+#include <QMessageBox>
+#include <QSettings>
+#include <QNetworkRequest>
+#include <QNetworkReply>
+#include <QJsonParseError>
+#include <QJsonDocument>
+#include <QJsonObject>
+#include <QJsonArray>
+#include <QJsonValue>
+
+#include "core/application.h"
+#include "core/player.h"
+#include "core/closure.h"
+#include "core/network.h"
+#include "core/song.h"
+#include "core/timeconstants.h"
+#include "core/logging.h"
+#include "internet/localredirectserver.h"
+#include "settings/settingsdialog.h"
+#include "settings/scrobblersettingspage.h"
+
+#include "audioscrobbler.h"
+#include "scrobblerservices.h"
+#include "scrobblerservice.h"
+#include "scrobblercache.h"
+#include "scrobblercacheitem.h"
+#include "listenbrainzscrobbler.h"
+
+const char *ListenBrainzScrobbler::kName = "ListenBrainz";
+const char *ListenBrainzScrobbler::kSettingsGroup = "ListenBrainz";
+const char *ListenBrainzScrobbler::kAuthUrl = "https://musicbrainz.org/oauth2/authorize";
+const char *ListenBrainzScrobbler::kAuthTokenUrl = "https://musicbrainz.org/oauth2/token";
+const char *ListenBrainzScrobbler::kRedirectUrl = "http://localhost";
+const char *ListenBrainzScrobbler::kApiUrl = "https://api.listenbrainz.org";
+const char *ListenBrainzScrobbler::kClientID = "oeAUNwqSQer0er09Fiqi0Q";
+const char *ListenBrainzScrobbler::kClientSecret = "ROFghkeQ3F3oPyEhqiyWPA";
+const char *ListenBrainzScrobbler::kCacheFile = "listenbrainzscrobbler.cache";
+const int ListenBrainzScrobbler::kScrobblesPerRequest = 10;
+
+ListenBrainzScrobbler::ListenBrainzScrobbler(Application *app, QObject *parent) : ScrobblerService(kName, app, parent),
+  app_(app),
+  network_(new NetworkAccessManager(this)),
+  cache_(new ScrobblerCache(kCacheFile, this)),
+  enabled_(false),
+  expires_in_(-1),
+  submitted_(false) {
+
+  ReloadSettings();
+  LoadSession();
+
+}
+
+ListenBrainzScrobbler::~ListenBrainzScrobbler() {}
+
+void ListenBrainzScrobbler::ReloadSettings() {
+
+  QSettings s;
+  s.beginGroup(kSettingsGroup);
+  enabled_ = s.value("enabled", false).toBool();
+  user_token_ = s.value("user_token").toString();
+  s.endGroup();
+
+}
+
+void ListenBrainzScrobbler::LoadSession() {
+
+  QSettings s;
+  s.beginGroup(kSettingsGroup);
+  access_token_ = s.value("access_token").toString();
+  expires_in_ = s.value("expires_in", -1).toInt();
+  token_type_ = s.value("token_type").toString();
+  refresh_token_ = s.value("refresh_token").toString();
+  s.endGroup();
+
+}
+
+void ListenBrainzScrobbler::Logout() {
+
+  access_token_.clear();
+  expires_in_ = -1;
+  token_type_.clear();
+  refresh_token_.clear();
+
+  QSettings settings;
+  settings.beginGroup(kSettingsGroup);
+  settings.remove("access_token");
+  settings.remove("expires_in");
+  settings.remove("token_type");
+  settings.remove("refresh_token");
+  settings.endGroup();
+
+}
+
+void ListenBrainzScrobbler::Authenticate() {
+
+  QUrl url(kAuthUrl);
+
+  LocalRedirectServer *server = new LocalRedirectServer(this);
+  server->Listen();
+  NewClosure(server, SIGNAL(Finished()), this, &ListenBrainzScrobbler::RedirectArrived, server);
+
+  QUrl redirect_url(kRedirectUrl);
+  redirect_url.setPort(server->url().port());
+
+  QUrlQuery url_query;
+  url_query.addQueryItem("response_type", "code");
+  url_query.addQueryItem("client_id", kClientID);
+  url_query.addQueryItem("redirect_uri", redirect_url.toString());
+  url_query.addQueryItem("scope", "profile;email;tag;rating;collection;submit_isrc;submit_barcode");
+  url.setQuery(url_query);
+
+  bool result = QDesktopServices::openUrl(url);
+  if (!result) {
+    QMessageBox box(QMessageBox::NoIcon, "Scrobbler Authentication", QString("Please open this URL in your browser: <a href=\"%1\">%1</a>").arg(url.toString()), QMessageBox::Ok);
+    box.setTextFormat(Qt::RichText);
+    qLog(Debug) << "Scrobbler authentication URL: " << url.toString();
+    box.exec();
+  }
+
+}
+
+void ListenBrainzScrobbler::RedirectArrived(LocalRedirectServer *server) {
+
+  server->deleteLater();
+
+  QUrl url = server->request_url();
+  if (!QUrlQuery(url).queryItemValue("error").isEmpty()) {
+    AuthError(QUrlQuery(url).queryItemValue("error"));
+    return;
+  }
+  if (QUrlQuery(url).queryItemValue("code").isEmpty()) {
+    AuthError("Redirect missing token code!");
+    return;
+  }
+
+  RequestSession(url, QUrlQuery(url).queryItemValue("code").toUtf8());
+
+}
+
+void ListenBrainzScrobbler::RequestSession(QUrl url, QString token) {
+
+  QUrl session_url(kAuthTokenUrl);
+  QUrlQuery url_query;
+  url_query.addQueryItem("grant_type", "authorization_code");
+  url_query.addQueryItem("code", token);
+  url_query.addQueryItem("client_id", kClientID);
+  url_query.addQueryItem("client_secret", kClientSecret);
+  url_query.addQueryItem("redirect_uri", url.toString());
+
+  QNetworkRequest req(session_url);
+  req.setHeader(QNetworkRequest::ContentTypeHeader, "application/x-www-form-urlencoded");
+  QByteArray query = url_query.toString(QUrl::FullyEncoded).toUtf8();
+  QNetworkReply *reply = network_->post(req, query);
+  NewClosure(reply, SIGNAL(finished()), this, SLOT(AuthenticateReplyFinished(QNetworkReply*)), reply);
+
+}
+
+void ListenBrainzScrobbler::AuthenticateReplyFinished(QNetworkReply *reply) {
+
+  reply->deleteLater();
+
+  QByteArray data;
+
+  if (reply->error() == QNetworkReply::NoError && reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt() == 200) {
+    data = reply->readAll();
+  }
+  else {
+    if (reply->error() < 200) {
+      // This is a network error, there is nothing more to do.
+      QString failure_reason = QString("%1 (%2)").arg(reply->errorString()).arg(reply->error());
+      AuthError(failure_reason);
+    }
+    else {
+      // See if there is Json data containing "error" and "error_description" - then use that instead.
+      data = reply->readAll();
+      QJsonParseError error;
+      QJsonDocument json_doc = QJsonDocument::fromJson(data, &error);
+      QString failure_reason;
+      if (error.error == QJsonParseError::NoError && !json_doc.isNull() && !json_doc.isEmpty() && json_doc.isObject()) {
+        QJsonObject json_obj = json_doc.object();
+        if (json_obj.contains("error") && json_obj.contains("error_description")) {
+          QString error = json_obj["error"].toString();
+          failure_reason = json_obj["error_description"].toString();
+        }
+        else {
+          failure_reason = QString("%1 (%2)").arg(reply->errorString()).arg(reply->error());
+        }
+      }
+      else {
+        failure_reason = QString("%1 (%2)").arg(reply->errorString()).arg(reply->error());
+      }
+      AuthError(failure_reason);
+    }
+    return;
+  }
+
+  QJsonObject json_obj = ExtractJsonObj(data);
+  if (json_obj.isEmpty()) {
+    AuthError("Json document from server was empty.");
+    return;
+  }
+  
+  if (json_obj.contains("error") && json_obj.contains("error_description")) {
+    QString error = json_obj["error"].toString();
+    QString failure_reason = json_obj["error_description"].toString();
+    AuthError(failure_reason);
+    return;
+  }
+
+  if (!json_obj.contains("access_token") || !json_obj.contains("expires_in") || !json_obj.contains("token_type") || !json_obj.contains("refresh_token")) {
+    AuthError("Json session object is missing values.");
+    return;
+  }
+
+  access_token_ = json_obj["access_token"].toString();
+  expires_in_ = json_obj["expires_in"].toInt();
+  token_type_ = json_obj["token_type"].toString();
+  refresh_token_ = json_obj["refresh_token"].toString();
+
+  QSettings s;
+  s.beginGroup(kSettingsGroup);
+  s.setValue("access_token", access_token_);
+  s.setValue("expires_in", expires_in_);
+  s.setValue("token_type", token_type_);
+  s.setValue("refresh_token", refresh_token_);
+  s.endGroup();
+
+  emit AuthenticationComplete(true);
+
+}
+
+QNetworkReply *ListenBrainzScrobbler::CreateRequest(const QUrl &url, const QJsonDocument &json_doc) {
+
+  QNetworkRequest req(url);
+  req.setHeader(QNetworkRequest::ContentTypeHeader, "application/json");
+  req.setRawHeader("Authorization", QString("Token %1").arg(user_token_).toUtf8());
+  QNetworkReply *reply = network_->post(req, json_doc.toJson());
+
+  //qLog(Debug) << "ListenBrainz: Sending request" << json_doc.toJson();
+
+  return reply;
+
+}
+
+QByteArray ListenBrainzScrobbler::GetReplyData(QNetworkReply *reply) {
+
+  QByteArray data;
+
+  if (reply->error() == QNetworkReply::NoError && reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt() == 200) {
+    data = reply->readAll();
+  }
+  else {
+    if (reply->error() < 200) {
+      // This is a network error, there is nothing more to do.
+      QString error_reason = QString("%1 (%2)").arg(reply->errorString()).arg(reply->error());
+      Error(error_reason);
+    }
+    else {
+      // See if there is Json data containing "error" and "error_description" - then use that instead.
+      data = reply->readAll();
+      QJsonParseError error;
+      QJsonDocument json_doc = QJsonDocument::fromJson(data, &error);
+      int error_code = -1;
+      QString error_reason;
+      if (error.error == QJsonParseError::NoError && !json_doc.isNull() && !json_doc.isEmpty() && json_doc.isObject()) {
+        QJsonObject json_obj = json_doc.object();
+        if (json_obj.contains("code") && json_obj.contains("error")) {
+          error_code = json_obj["code"].toInt();
+          QString message = json_obj["error"].toString();
+          error_reason = QString("%1 (%2)").arg(message).arg(error_code);
+        }
+        else {
+          error_reason = QString("%1 (%2)").arg(reply->errorString()).arg(reply->error());
+        }
+      }
+      else {
+        error_reason = QString("%1 (%2)").arg(reply->errorString()).arg(reply->error());
+      }
+      if (reply->error() == QNetworkReply::ContentAccessDenied || reply->error() == QNetworkReply::ContentOperationNotPermittedError || reply->error() == QNetworkReply::AuthenticationRequiredError) {
+        // Session is probably expired
+        Logout();
+        Error(error_reason);
+      }
+      else if (reply->error() == QNetworkReply::ContentNotFoundError) { // Ignore this error
+        Error(error_reason);
+      }
+      else { // Fail
+        Error(error_reason);
+      }
+    }
+    return QByteArray();
+  }
+
+  return data;
+  
+}
+
+void ListenBrainzScrobbler::UpdateNowPlaying(const Song &song) {
+
+  song_playing_ = song;
+  timestamp_ = QDateTime::currentDateTime().toTime_t();
+
+  if (!song.is_metadata_good()) return;
+
+  // FIXME: This does not work: BAD REQUEST (302)
+  return;
+
+  QJsonObject object_listen;
+  object_listen.insert("listened_at", QJsonValue::fromVariant(timestamp_));
+  QJsonObject object_track_metadata;
+  object_track_metadata.insert("artist_name", QJsonValue::fromVariant(song.artist()));
+  object_track_metadata.insert("release_name", QJsonValue::fromVariant(song.album()));
+  object_track_metadata.insert("track_name", QJsonValue::fromVariant(song.title()));
+  object_listen.insert("track_metadata", object_track_metadata);
+
+  QJsonArray array_payload;
+  array_payload.append(object_listen);
+
+  QJsonObject object;
+  object.insert("listen_type", "playing_now");
+  object.insert("payload", array_payload);
+  QJsonDocument doc(object);
+
+  QUrl url(QString("%1/1/submit-listens").arg(kApiUrl));
+  QNetworkReply *reply = CreateRequest(url, doc);
+  NewClosure(reply, SIGNAL(finished()), this, SLOT(UpdateNowPlayingRequestFinished(QNetworkReply*)), reply);
+
+}
+
+void ListenBrainzScrobbler::UpdateNowPlayingRequestFinished(QNetworkReply *reply) {
+
+  reply->deleteLater();
+
+  QByteArray data = GetReplyData(reply);
+  if (data.isEmpty()) {
+    return;
+  }
+  qLog(Debug) << data;
+
+  // TODO
+
+}
+
+void ListenBrainzScrobbler::Scrobble(const Song &song) {
+
+  if (song.id() != song_playing_.id() || song.url() != song_playing_.url() || !song.is_metadata_good()) return;
+
+  cache_->Add(song, timestamp_);
+
+  if (app_->scrobbler()->IsOffline()) return;
+
+  if (!IsAuthenticated()) {
+    emit ErrorMessage("ListenBrainz is not authenticated!");
+    return;
+  }
+
+  if (!submitted_) {
+    DoInAMinuteOrSo(this, SLOT(Submit()));
+    submitted_ = true;
+  }
+
+}
+
+void ListenBrainzScrobbler::Submit() {
+
+  qLog(Debug) << __PRETTY_FUNCTION__;
+
+  submitted_ = false;
+
+  if (!IsEnabled() || !IsAuthenticated() || app_->scrobbler()->IsOffline()) return;
+
+  QJsonArray array;
+  int i(0);
+  QList<quint64> list;
+  for (ScrobblerCacheItem *item : cache_->List()) {
+    if (item->sent_) continue;
+    item->sent_ = true;
+    i++;
+    list << item->timestamp_;
+    QJsonObject object_listen;
+    object_listen.insert("listened_at", QJsonValue::fromVariant(item->timestamp_));
+    QJsonObject object_track_metadata;
+    object_track_metadata.insert("artist_name", QJsonValue::fromVariant(item->artist_));
+    object_track_metadata.insert("release_name", QJsonValue::fromVariant(item->album_));
+    object_track_metadata.insert("track_name", QJsonValue::fromVariant(item->song_));
+    object_listen.insert("track_metadata", object_track_metadata);
+    array.append(QJsonValue::fromVariant(object_listen));
+    if (i >= kScrobblesPerRequest) break;
+  }
+
+  if (i <= 0) return;
+
+  QJsonObject object;
+  object.insert("listen_type", "import");
+  object.insert("payload", array);
+  QJsonDocument doc(object);
+
+  QUrl url(QString("%1/1/submit-listens").arg(kApiUrl));
+  QNetworkReply *reply = CreateRequest(url, doc);
+  NewClosure(reply, SIGNAL(finished()), this, SLOT(ScrobbleRequestFinished(QNetworkReply*, QList<quint64>)), reply, list);
+
+}
+
+void ListenBrainzScrobbler::ScrobbleRequestFinished(QNetworkReply *reply, QList<quint64> list) {
+
+  reply->deleteLater();
+
+  QByteArray data = GetReplyData(reply);
+  if (data.isEmpty()) {
+    cache_->ClearSent(list);
+    return;
+  }
+
+  QJsonObject json_obj = ExtractJsonObj(data);
+  if (json_obj.isEmpty()) {
+    cache_->ClearSent(list);
+    return;
+  }
+
+  if (json_obj.contains("error") && json_obj.contains("error_description")) {
+    QString error_code = json_obj["error"].toString();
+    QString error_desc = json_obj["error_description"].toString();
+    Error(error_desc);
+    cache_->ClearSent(list);
+    return;
+  }
+
+  if (json_obj.contains("status")) {
+    QString status = json_obj["status"].toString();
+    qLog(Debug) << "MusicBrainz: Received scrobble status:" << status;
+  }
+
+  cache_->Flush(list);
+
+}
+
+void ListenBrainzScrobbler::Love(const Song &song) {}
+
+void ListenBrainzScrobbler::AuthError(QString error) {
+  emit AuthenticationComplete(false, error);
+}
+
+void ListenBrainzScrobbler::Error(QString error, QVariant debug) {
+
+  qLog(Error) << "ListenBrainz:" << error;
+  if (debug.isValid()) qLog(Debug) << debug;
+
+}
+

src/scrobbler/listenbrainzscrobbler.h

@@ -0,0 +1,117 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef LISTENBRAINZSCROBBLER_H
+#define LISTENBRAINZSCROBBLER_H
+
+#include "config.h"
+
+#include <memory>
+
+#include <QtGlobal>
+#include <QObject>
+#include <QNetworkReply>
+#include <QPair>
+#include <QList>
+#include <QVariant>
+#include <QByteArray>
+#include <QString>
+#include <QJsonObject>
+
+#include "core/song.h"
+#include "scrobblerservice.h"
+#include "scrobblercache.h"
+
+class Application;
+class NetworkAccessManager;
+class LocalRedirectServer;
+class ScrobblerCacheItem;
+
+class ListenBrainzScrobbler : public ScrobblerService {
+  Q_OBJECT
+
+ public:
+  explicit ListenBrainzScrobbler(Application *app, QObject *parent = nullptr);
+  ~ListenBrainzScrobbler();
+
+  static const char *kName;
+  static const char *kSettingsGroup;
+
+  void ReloadSettings();
+  void LoadSession();
+
+  bool IsEnabled() const { return enabled_; }
+  bool IsAuthenticated() const { return !access_token_.isEmpty() && !user_token_.isEmpty(); }
+  bool IsSubmitted() const { return submitted_; }
+  void Submitted() { submitted_ = true; }
+  QString user_token() const { return user_token_; }
+
+  void Authenticate();
+  void Logout();
+  void ShowConfig();
+  void Submit();
+  void UpdateNowPlaying(const Song &song);
+  void Scrobble(const Song &song);
+  void Love(const Song &song);
+
+ signals:
+  void AuthenticationComplete(bool success, QString error = QString());
+
+ public slots:
+  void WriteCache() { cache_->WriteCache(); }
+
+ private slots:
+  void RedirectArrived(LocalRedirectServer *server);
+  void AuthenticateReplyFinished(QNetworkReply *reply);
+  void UpdateNowPlayingRequestFinished(QNetworkReply *reply);
+  void ScrobbleRequestFinished(QNetworkReply *reply, QList<quint64>);
+
+ private:
+  QNetworkReply *CreateRequest(const QUrl &url, const QJsonDocument &json_doc);
+  QByteArray GetReplyData(QNetworkReply *reply);
+
+  void RequestSession(QUrl url, QString token);
+  void AuthError(QString error);
+  void Error(QString error, QVariant debug = QVariant());
+
+  static const char *kAuthUrl;
+  static const char *kAuthTokenUrl;
+  static const char *kApiUrl;
+  static const char *kClientID;
+  static const char *kClientSecret;
+  static const char *kCacheFile;
+  static const char *kRedirectUrl;
+  static const int kScrobblesPerRequest;
+
+  Application *app_;
+  NetworkAccessManager *network_;
+  ScrobblerCache *cache_;
+  bool enabled_;
+  QString user_token_;
+  QString access_token_;
+  qint64 expires_in_;
+  QString token_type_;
+  QString refresh_token_;
+  bool submitted_;
+  Song song_playing_;
+  quint64 timestamp_;
+
+};
+
+#endif  // LISTENBRAINZSCROBBLER_H

src/scrobbler/scrobblercache.cpp

@@ -0,0 +1,230 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include <QObject>
+#include <QStandardPaths>
+#include <QString>
+#include <QFile>
+#include <QIODevice>
+#include <QTextStream>
+#include <QDateTime>
+#include <QMultiHash>
+#include <QJsonValue>
+#include <QJsonDocument>
+#include <QJsonObject>
+#include <QJsonArray>
+#include <QJsonParseError>
+
+#include "core/song.h"
+#include "core/logging.h"
+#include "core/closure.h"
+
+#include "scrobblercache.h"
+#include "scrobblercacheitem.h"
+
+ScrobblerCache::ScrobblerCache(const QString &filename, QObject *parent) :
+  QObject(parent),
+  filename_(QStandardPaths::writableLocation(QStandardPaths::CacheLocation) + "/" + filename),
+  loaded_(false) {
+  ReadCache();
+  loaded_ = true;
+}
+
+ScrobblerCache::~ScrobblerCache() {}
+
+void ScrobblerCache::ReadCache() {
+
+  QFile file(filename_);
+  bool result = file.open(QIODevice::ReadOnly | QIODevice::Text);
+  if (!result) return;
+
+  QTextStream stream(&file);
+  stream.setCodec("UTF-8");
+  QString data = stream.readAll();
+  file.close();
+
+  if (data.isEmpty()) return;
+
+  QJsonParseError error;
+  QJsonDocument json_doc = QJsonDocument::fromJson(data.toUtf8(), &error);
+  if (error.error != QJsonParseError::NoError) {
+    qLog(Error) << "Scrobbler cache is missing JSON data.";
+    return;
+  }
+  if (json_doc.isNull() || json_doc.isEmpty()) {
+    qLog(Error) << "Scrobbler cache has empty JSON document.";
+    return;
+  }
+  if (!json_doc.isObject()) {
+    qLog(Error) << "Scrobbler cache JSON document is not an object.";
+    return;
+  }
+  QJsonObject json_obj = json_doc.object();
+  if (json_obj.isEmpty()) {
+    qLog(Error) << "Scrobbler cache has empty JSON object.";
+    return;
+  }
+  if (!json_obj.contains("tracks")) {
+    qLog(Error) << "Scrobbler cache is missing JSON tracks.";
+    return;
+  }
+  QJsonValue json_tracks = json_obj["tracks"];
+  if (!json_tracks.isArray()) {
+    qLog(Error) << "Scrobbler cache JSON tracks is not an array.";
+    return;
+  }
+  QJsonArray json_array = json_tracks.toArray();
+  if (json_array.isEmpty()) {
+    return;
+  }
+
+  for (const QJsonValue &value : json_array) {
+    if (!value.isObject()) {
+      qLog(Error) << "Scrobbler cache JSON tracks array value is not an object.";
+      qLog(Debug) << value;
+      continue;
+    }
+    QJsonObject json_obj_track = value.toObject();
+    if (
+        !json_obj_track.contains("timestamp") ||
+        !json_obj_track.contains("song") ||
+        !json_obj_track.contains("album") ||
+        !json_obj_track.contains("artist") ||
+        !json_obj_track.contains("albumartist") ||
+        !json_obj_track.contains("track") ||
+        !json_obj_track.contains("duration")
+    ) {
+      qLog(Error) << "Scrobbler cache JSON tracks array value is missing data.";
+      qLog(Debug) << value;
+      continue;
+    }
+
+    quint64 timestamp = json_obj_track["timestamp"].toVariant().toULongLong();
+    QString artist = json_obj_track["artist"].toString();
+    QString album = json_obj_track["album"].toString();
+    QString song = json_obj_track["song"].toString();
+    QString albumartist = json_obj_track["albumartist"].toString();
+    int track = json_obj_track["track"].toInt();
+    qint64 duration = json_obj_track["duration"].toVariant().toLongLong();
+
+    if (timestamp <= 0 || artist.isEmpty() || album.isEmpty() || song.isEmpty() || duration <= 0) {
+      qLog(Error) << "Invalid cache data" << "for song" << song;
+      continue;
+    }
+    if (scrobbler_cache_.contains(timestamp)) continue;
+    ScrobblerCacheItem *item = new ScrobblerCacheItem(artist, album, song, albumartist, track, duration, timestamp);
+    scrobbler_cache_.insert(timestamp, item);
+
+  }
+
+}
+
+void ScrobblerCache::WriteCache() {
+
+  if (!loaded_) return;
+
+  qLog(Debug) << "Writing scrobbler cache file" << filename_;
+
+  QJsonArray array;
+
+  QMultiHash <quint64, ScrobblerCacheItem*> ::iterator i;
+  for (i = scrobbler_cache_.begin() ; i != scrobbler_cache_.end() ; ++i) {
+    ScrobblerCacheItem *item = i.value();
+    QJsonObject object;
+    object.insert("timestamp", QJsonValue::fromVariant(item->timestamp_));
+    object.insert("artist", QJsonValue::fromVariant(item->artist_));
+    object.insert("album", QJsonValue::fromVariant(item->album_));
+    object.insert("song", QJsonValue::fromVariant(item->song_));
+    object.insert("albumartist", QJsonValue::fromVariant(item->albumartist_));
+    object.insert("track", QJsonValue::fromVariant(item->track_));
+    object.insert("duration", QJsonValue::fromVariant(item->duration_));
+    array.append(QJsonValue::fromVariant(object));
+  }
+
+  QJsonObject object;
+  object.insert("tracks", array);
+  QJsonDocument doc(object);
+
+  QFile file(filename_);
+  bool result = file.open(QIODevice::WriteOnly | QIODevice::Text);
+  if (!result) {
+    qLog(Error) << "Unable to open scrobbler cache file" << filename_;
+    return;
+  }
+  QTextStream stream(&file);
+  stream.setCodec("UTF-8");
+  stream << doc.toJson();
+  file.close();
+
+}
+
+ScrobblerCacheItem *ScrobblerCache::Add(const Song &song, const quint64 &timestamp) {
+
+  if (scrobbler_cache_.contains(timestamp)) return nullptr;
+
+  ScrobblerCacheItem *item = new ScrobblerCacheItem(song.artist(), song.album(), song.title(), song.albumartist(), song.track(), song.length_nanosec(), timestamp);
+  scrobbler_cache_.insert(timestamp, item);
+
+  if (loaded_) DoInAMinuteOrSo(this, SLOT(WriteCache()));
+
+  return item;
+
+}
+
+ScrobblerCacheItem *ScrobblerCache::Get(const quint64 hash) {
+
+  if (scrobbler_cache_.contains(hash)) { return scrobbler_cache_.value(hash); }
+  else return nullptr;
+
+}
+
+void ScrobblerCache::Remove(const quint64 hash) {
+
+  if (!scrobbler_cache_.contains(hash)) {
+    qLog(Error) << "Tried to remove non-existing hash" << hash;
+    return;
+  }
+
+  delete scrobbler_cache_.take(hash);
+
+}
+
+void ScrobblerCache::Remove(ScrobblerCacheItem &item) {
+  delete scrobbler_cache_.take(item.timestamp_);
+}
+
+void ScrobblerCache::ClearSent(const QList<quint64> list) {
+  for (quint64 timestamp : list) {
+    if (!scrobbler_cache_.contains(timestamp)) continue;
+    ScrobblerCacheItem *item = scrobbler_cache_.take(timestamp);
+    item->sent_ = false;
+  }
+}
+
+void ScrobblerCache::Flush(const QList<quint64> list) {
+
+  for (quint64 timestamp : list) {
+    if (!scrobbler_cache_.contains(timestamp)) continue;
+    delete scrobbler_cache_.take(timestamp);
+  }
+  DoInAMinuteOrSo(this, SLOT(WriteCache()));
+
+}

src/scrobbler/scrobblercache.h

@@ -0,0 +1,64 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef SCROBBLERCACHE_H
+#define SCROBBLERCACHE_H
+
+#include "config.h"
+
+#include <stdbool.h>
+
+#include <QObject>
+#include <QList>
+#include <QHash>
+#include <QString>
+#include <QDateTime>
+
+class Application;
+class Song;
+class ScrobblerCacheItem;
+
+class ScrobblerCache : public QObject {
+  Q_OBJECT
+
+ public:
+  explicit ScrobblerCache(const QString &filename, QObject *parent);
+  ~ScrobblerCache();
+
+  void ReadCache();
+
+  ScrobblerCacheItem *Add(const Song &song, const quint64 &timestamp);
+  ScrobblerCacheItem *Get(const quint64 hash);
+  void Remove(const quint64 hash);
+  void Remove(ScrobblerCacheItem &item);
+  QList<ScrobblerCacheItem*> List() const { return scrobbler_cache_.values(); }
+  void ClearSent(const QList<quint64> list);
+  void Flush(const QList<quint64> list);
+
+ public slots:
+  void WriteCache();
+
+ private:
+  QString filename_;
+  bool loaded_;
+  QHash <quint64, ScrobblerCacheItem*> scrobbler_cache_;
+
+};
+
+#endif  // SCROBBLERCACHE_H

src/scrobbler/scrobblercacheitem.cpp

@@ -0,0 +1,39 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include <QObject>
+#include <QtGlobal>
+#include <QString>
+#include <QHash>
+
+#include "scrobblercacheitem.h"
+
+ScrobblerCacheItem::ScrobblerCacheItem(const QString &artist, const QString &album, const QString &song, const QString &albumartist, const int track, const qint64 duration, const quint64 &timestamp) :
+  artist_(artist),
+  album_(album),
+  song_(song),
+  albumartist_(albumartist),
+  track_(track),
+  duration_(duration),
+  timestamp_(timestamp),
+  sent_(false) {}
+
+ScrobblerCacheItem::~ScrobblerCacheItem() {}

src/scrobbler/scrobblercacheitem.h

@@ -0,0 +1,48 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef SCROBBLERCACHEITEM_H
+#define SCROBBLERCACHEITEM_H
+
+#include "config.h"
+
+#include <QtGlobal>
+#include <QObject>
+#include <QString>
+
+class ScrobblerCacheItem : public QObject {
+  Q_OBJECT
+
+ public:
+  explicit ScrobblerCacheItem(const QString &artist, const QString &album, const QString &song, const QString &albumartist, const int track, const qint64 duration, const quint64 &timestamp);
+  ~ScrobblerCacheItem();
+
+ public:
+  QString artist_;
+  QString album_;
+  QString song_;
+  QString albumartist_;
+  int track_;
+  qint64 duration_;
+  quint64 timestamp_;
+  bool sent_;
+
+};
+
+#endif  // SCROBBLERCACHEITEM_H

src/scrobbler/scrobblerservice.cpp

@@ -0,0 +1,57 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include <QObject>
+#include <QString>
+#include <QByteArray>
+#include <QJsonDocument>
+#include <QJsonObject>
+
+#include "scrobblerservice.h"
+
+ScrobblerService::ScrobblerService(const QString &name, Application *app, QObject *parent) : QObject(parent), name_(name) {}
+
+QJsonObject ScrobblerService::ExtractJsonObj(const QByteArray &data) {
+
+  QJsonParseError error;
+  QJsonDocument json_doc = QJsonDocument::fromJson(data, &error);
+
+  if (error.error != QJsonParseError::NoError) {
+    Error("Reply from server missing Json data.", data);
+    return QJsonObject();
+  }
+  if (json_doc.isNull() || json_doc.isEmpty()) {
+    Error("Received empty Json document.", json_doc);
+    return QJsonObject();
+  }
+  if (!json_doc.isObject()) {
+    Error("Json document is not an object.", json_doc);
+    return QJsonObject();
+  }
+  QJsonObject json_obj = json_doc.object();
+  if (json_obj.isEmpty()) {
+    Error("Received empty Json object.", json_doc);
+    return QJsonObject();
+  }
+
+  return json_obj;
+
+}

src/scrobbler/scrobblerservice.h

@@ -0,0 +1,76 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef SCROBBLERSERVICE_H
+#define SCROBBLERSERVICE_H
+
+#include "config.h"
+
+#include <stdbool.h>
+
+#include <QObject>
+#include <QString>
+#include <QVariant>
+#include <QByteArray>
+#include <QJsonDocument>
+#include <QJsonObject>
+
+class Application;
+class Song;
+
+class ScrobblerService : public QObject {
+  Q_OBJECT
+
+ public:
+  explicit ScrobblerService(const QString &name, Application *app, QObject *parent);
+
+  QString name() const { return name_; }
+
+  virtual void ReloadSettings() = 0;
+
+  virtual bool IsEnabled() const { return false; }
+  virtual bool IsAuthenticated() const { return false; }
+
+  virtual void UpdateNowPlaying(const Song &song) = 0;
+  virtual void Scrobble(const Song &song) = 0;
+  virtual void Love(const Song &song) = 0;
+  virtual void Error(QString error, QVariant debug = QVariant()) = 0;
+
+  virtual void Submitted() = 0;
+  virtual bool IsSubmitted() const { return false; }
+
+  typedef QPair<QString, QString> Param;
+  typedef QPair<QByteArray, QByteArray> EncodedParam;
+  typedef QList<Param> ParamList;
+
+  QJsonObject ExtractJsonObj(const QByteArray &data);
+
+ public slots:
+  virtual void Submit() = 0;
+  virtual void WriteCache() = 0;
+
+ signals:
+  void ErrorMessage(QString);
+
+ private:
+  QString name_;
+
+};
+
+#endif  // SCROBBLERSERVICE_H

src/scrobbler/scrobblerservices.cpp

@@ -0,0 +1,77 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include <QObject>
+#include <QMutexLocker>
+#include <QString>
+#include <QtDebug>
+
+#include "core/application.h"
+#include "core/logging.h"
+
+#include "scrobblerservices.h"
+#include "scrobblerservice.h"
+
+ScrobblerServices::ScrobblerServices(QObject *parent) : QObject(parent) {}
+
+ScrobblerServices::~ScrobblerServices() {}
+
+void ScrobblerServices::AddService(ScrobblerService *service) {
+
+  {
+    QMutexLocker locker(&mutex_);
+    scrobbler_services_.insert(service->name(), service);
+    connect(service, SIGNAL(destroyed()), SLOT(ServiceDestroyed()));
+  }
+
+  qLog(Debug) << "Registered scrobbler service" << service->name();
+
+}
+
+void ScrobblerServices::RemoveService(ScrobblerService *service) {
+
+  if (!service || !scrobbler_services_.contains(service->name())) return;
+
+  {
+    QMutexLocker locker(&mutex_);
+    scrobbler_services_.remove(service->name());
+    disconnect(service, 0, this, 0);
+  }
+
+  qLog(Debug) << "Unregistered scrobbler service" << service->name();
+
+}
+
+void ScrobblerServices::ServiceDestroyed() {
+
+  ScrobblerService *service = static_cast<ScrobblerService*>(sender());
+  RemoveService(service);
+
+}
+
+int ScrobblerServices::NextId() { return next_id_.fetchAndAddRelaxed(1); }
+
+ScrobblerService *ScrobblerServices::ServiceByName(const QString &name) {
+
+  if (scrobbler_services_.contains(name)) return scrobbler_services_.value(name);
+  return nullptr;
+
+}

src/scrobbler/scrobblerservices.h

@@ -0,0 +1,70 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef SCROBBLERSERVICES_H
+#define SCROBBLERSERVICES_H
+
+#include "config.h"
+
+#include <stdbool.h>
+
+#include <QtGlobal>
+#include <QObject>
+#include <QMutex>
+#include <QList>
+#include <QMap>
+#include <QString>
+#include <QAtomicInt>
+
+class Application;
+class ScrobblerService;
+
+class ScrobblerServices : public QObject {
+  Q_OBJECT
+
+ public:
+  explicit ScrobblerServices(QObject *parent = nullptr);
+  ~ScrobblerServices();
+
+  void AddService(ScrobblerService *service);
+  void RemoveService(ScrobblerService *service);
+  QList<ScrobblerService*> List() const { return scrobbler_services_.values(); }
+  bool HasAnyServices() const { return !scrobbler_services_.isEmpty(); }
+  int NextId();
+
+  ScrobblerService *ServiceByName(const QString &name);
+  template <typename T>
+  T *Service() {
+    return static_cast<T*>(this->ServiceByName(T::kName));
+  }
+
+ private slots:
+  void ServiceDestroyed();
+
+ private:
+  Q_DISABLE_COPY(ScrobblerServices);
+
+  QMap<QString, ScrobblerService *> scrobbler_services_;
+  QMutex mutex_;
+
+  QAtomicInt next_id_;
+
+};
+
+#endif  // SCROBBLERSERVICES_H

src/scrobbler/scrobblingapi20.cpp

@@ -0,0 +1,740 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "config.h"
+
+#include <algorithm>
+
+#include <QtGlobal>
+#include <QDesktopServices>
+#include <QVariant>
+#include <QByteArray>
+#include <QString>
+#include <QUrl>
+#include <QUrlQuery>
+#include <QDateTime>
+#include <QCryptographicHash>
+#include <QMenu>
+#include <QMessageBox>
+#include <QSettings>
+#include <QNetworkRequest>
+#include <QNetworkReply>
+#include <QJsonParseError>
+#include <QJsonDocument>
+#include <QJsonObject>
+#include <QJsonArray>
+#include <QJsonValue>
+
+#include "core/application.h"
+#include "core/player.h"
+#include "core/closure.h"
+#include "core/network.h"
+#include "core/song.h"
+#include "core/timeconstants.h"
+#include "core/logging.h"
+#include "internet/localredirectserver.h"
+#include "settings/settingsdialog.h"
+#include "settings/scrobblersettingspage.h"
+
+#include "audioscrobbler.h"
+#include "scrobblerservices.h"
+#include "scrobblingapi20.h"
+#include "scrobblercache.h"
+#include "scrobblercacheitem.h"
+
+const char *ScrobblingAPI20::kApiKey = "211990b4c96782c05d1536e7219eb56e";
+const char *ScrobblingAPI20::kSecret = "80fd738f49596e9709b1bf9319c444a8";
+const char *ScrobblingAPI20::kRedirectUrl = "https://oauth.strawbs.net";
+const int ScrobblingAPI20::kScrobblesPerRequest = 50;
+
+ScrobblingAPI20::ScrobblingAPI20(const QString &name, const QString &settings_group, const QString &auth_url, const QString &api_url, const bool batch, Application *app, QObject *parent) :
+  ScrobblerService(name, app, parent),
+  name_(name),
+  settings_group_(settings_group),
+  auth_url_(auth_url),
+  api_url_(api_url),
+  batch_(batch),
+  app_(app),
+  enabled_(false),
+  subscriber_(false),
+  submitted_(false) {}
+
+ScrobblingAPI20::~ScrobblingAPI20() {}
+
+void ScrobblingAPI20::ReloadSettings() {
+
+  QSettings s;
+  s.beginGroup(settings_group_);
+  enabled_ = s.value("enabled", false).toBool();
+  s.endGroup();
+
+}
+
+void ScrobblingAPI20::LoadSession() {
+
+  QSettings s;
+  s.beginGroup(settings_group_);
+  subscriber_ = s.value("subscriber", false).toBool();
+  username_ = s.value("username").toString();
+  session_key_ = s.value("session_key").toString();
+  s.endGroup();
+
+}
+
+void ScrobblingAPI20::Logout() {
+
+  subscriber_ = false;
+  username_.clear();
+  session_key_.clear();
+
+  QSettings settings;
+  settings.beginGroup(settings_group_);
+  settings.remove("subscriber");
+  settings.remove("username");
+  settings.remove("session_key");
+  settings.endGroup();
+
+}
+
+void ScrobblingAPI20::Authenticate() {
+
+  QUrl url(auth_url_);
+
+  LocalRedirectServer *server = new LocalRedirectServer(this);
+  server->Listen();
+  NewClosure(server, SIGNAL(Finished()), this, &ScrobblingAPI20::RedirectArrived, server);
+
+  QUrl redirect_url(kRedirectUrl);
+  QUrlQuery redirect_url_query;
+  const QString port = QString::number(server->url().port());
+  redirect_url_query.addQueryItem("port", port);  
+  redirect_url.setQuery(redirect_url_query);
+
+  QUrlQuery url_query;
+  url_query.addQueryItem("api_key", kApiKey);
+  url_query.addQueryItem("cb", redirect_url.toString());
+  url.setQuery(url_query);
+
+  bool result = QDesktopServices::openUrl(url);
+  if (!result) {
+    QMessageBox box(QMessageBox::NoIcon, "Scrobbler Authentication", QString("Please open this URL in your browser: <a href=\"%1\">%1</a>").arg(url.toString()), QMessageBox::Ok);
+    box.setTextFormat(Qt::RichText);
+    qLog(Debug) << "Scrobbler authentication URL: " << url.toString();
+    box.exec();
+  }
+
+}
+
+void ScrobblingAPI20::RedirectArrived(LocalRedirectServer *server) {
+
+  server->deleteLater();
+
+  QUrl url = server->request_url();
+  RequestSession(QUrlQuery(url).queryItemValue("token").toUtf8());
+
+}
+
+void ScrobblingAPI20::RequestSession(QString token) {
+
+  QUrl session_url(api_url_);
+  QUrlQuery session_url_query;
+  session_url_query.addQueryItem("api_key", kApiKey);
+  session_url_query.addQueryItem("method", "auth.getSession");
+  session_url_query.addQueryItem("token", token);
+  QString data_to_sign;
+  for (QPair<QString, QString> param : session_url_query.queryItems()) {
+    data_to_sign += param.first + param.second;
+  }
+  data_to_sign += kSecret;
+  QByteArray const digest = QCryptographicHash::hash(data_to_sign.toUtf8(), QCryptographicHash::Md5);
+  QString signature = QString::fromLatin1(digest.toHex()).rightJustified(32, '0').toLower();
+  session_url_query.addQueryItem("api_sig", signature);
+  session_url_query.addQueryItem(QUrl::toPercentEncoding("format"), QUrl::toPercentEncoding("json"));
+  session_url.setQuery(session_url_query);
+
+  QNetworkRequest req(session_url);
+  QNetworkReply *reply = network()->get(req);
+  NewClosure(reply, SIGNAL(finished()), this, SLOT(AuthenticateReplyFinished(QNetworkReply*)), reply);
+
+}
+
+void ScrobblingAPI20::AuthenticateReplyFinished(QNetworkReply *reply) {
+
+  reply->deleteLater();
+
+  QByteArray data;
+
+  if (reply->error() == QNetworkReply::NoError && reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt() == 200) {
+    data = reply->readAll();
+  }
+  else {
+    if (reply->error() < 200) {
+      // This is a network error, there is nothing more to do.
+      QString failure_reason = QString("%1 (%2)").arg(reply->errorString()).arg(reply->error());
+      AuthError(failure_reason);
+    }
+    else {
+      // See if there is Json data containing "error" and "message" - then use that instead.
+      data = reply->readAll();
+      QJsonParseError error;
+      QJsonDocument json_doc = QJsonDocument::fromJson(data, &error);
+      QString failure_reason;
+      if (error.error == QJsonParseError::NoError && !json_doc.isNull() && !json_doc.isEmpty() && json_doc.isObject()) {
+        QJsonObject json_obj = json_doc.object();
+        if (json_obj.contains("error") && json_obj.contains("message")) {
+          int error = json_obj["error"].toInt();
+          QString message = json_obj["message"].toString();
+          failure_reason = "Error: " + QString::number(error) + ": " + message;
+        }
+        else {
+          failure_reason = QString("%1 (%2)").arg(reply->errorString()).arg(reply->error());
+        }
+      }
+      else {
+        failure_reason = QString("%1 (%2)").arg(reply->errorString()).arg(reply->error());
+      }
+      AuthError(failure_reason);
+    }
+    return;
+  }
+  
+  QJsonObject json_obj = ExtractJsonObj(data);
+  if (json_obj.isEmpty()) {
+    AuthError("Json document from server was empty.");
+    return;
+  }
+  
+  if (json_obj.contains("error") && json_obj.contains("message")) {
+    int error = json_obj["error"].toInt();
+    QString message = json_obj["message"].toString();
+    QString failure_reason = "Error: " + QString::number(error) + ": " + message;
+    AuthError(failure_reason);
+    return;
+  }
+
+  if (!json_obj.contains("session")) {
+    AuthError("Json reply from server is missing session.");
+    return;
+  }
+
+  QJsonValue json_session = json_obj["session"];
+  if (!json_session.isObject()) {
+    AuthError("Json session is not an object.");
+    return;
+  }
+  json_obj = json_session.toObject();
+  if (json_obj.isEmpty()) {
+    AuthError("Json session object is empty.");
+    return;
+  }
+  if (!json_obj.contains("subscriber") || !json_obj.contains("name") || !json_obj.contains("key")) {
+    AuthError("Json session object is missing values.");
+    return;
+  }
+
+  subscriber_ = json_obj["subscriber"].toBool();
+  username_ = json_obj["name"].toString();
+  session_key_ = json_obj["key"].toString();
+  
+  QSettings s;
+  s.beginGroup(settings_group_);
+  s.setValue("subscriber", subscriber_);
+  s.setValue("username", username_);
+  s.setValue("session_key", session_key_);
+  s.endGroup();
+
+  emit AuthenticationComplete(true);
+
+}
+
+QNetworkReply *ScrobblingAPI20::CreateRequest(const ParamList &request_params) {
+
+  ParamList params = ParamList()
+    << Param("api_key", kApiKey)
+    << Param("sk", session_key_)
+    << Param("lang", QLocale().name().left(2).toLower())
+    << request_params;
+
+  std::sort(params.begin(), params.end());
+
+  QUrlQuery url_query;
+  QString data_to_sign;
+  for (const Param &param : params) {
+    EncodedParam encoded_param(QUrl::toPercentEncoding(param.first), QUrl::toPercentEncoding(param.second));
+    url_query.addQueryItem(encoded_param.first, encoded_param.second);
+    data_to_sign += param.first + param.second;
+  }
+  data_to_sign += kSecret;
+
+  QByteArray const digest = QCryptographicHash::hash(data_to_sign.toUtf8(), QCryptographicHash::Md5);
+  QString signature = QString::fromLatin1(digest.toHex()).rightJustified(32, '0').toLower();
+
+  url_query.addQueryItem("api_sig", QUrl::toPercentEncoding(signature));
+  url_query.addQueryItem("format", QUrl::toPercentEncoding("json"));
+
+  QUrl url(api_url_);
+  QNetworkRequest req(url);
+  req.setHeader(QNetworkRequest::ContentTypeHeader, "application/x-www-form-urlencoded");
+  QByteArray query = url_query.toString(QUrl::FullyEncoded).toUtf8();
+  QNetworkReply *reply = network()->post(req, query);
+
+  //qLog(Debug) << name_ << "Sending request" << query;
+
+  return reply;
+
+}
+
+QByteArray ScrobblingAPI20::GetReplyData(QNetworkReply *reply) {
+
+  QByteArray data;
+
+  if (reply->error() == QNetworkReply::NoError && reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt() == 200) {
+    data = reply->readAll();
+  }
+  else {
+    if (reply->error() < 200) {
+      // This is a network error, there is nothing more to do.
+      QString error_reason = QString("%1 (%2)").arg(reply->errorString()).arg(reply->error());
+      Error(error_reason);
+    }
+    else {
+      // See if there is Json data containing "error" and "message" - then use that instead.
+      data = reply->readAll();
+      QJsonParseError error;
+      QJsonDocument json_doc = QJsonDocument::fromJson(data, &error);
+      int error_code = -1;
+      QString error_reason;
+      if (error.error == QJsonParseError::NoError && !json_doc.isNull() && !json_doc.isEmpty() && json_doc.isObject()) {
+        QJsonObject json_obj = json_doc.object();
+        if (json_obj.contains("error") && json_obj.contains("message")) {
+          error_code = json_obj["error"].toInt();
+          QString message = json_obj["message"].toString();
+          error_reason = QString("%1 (%2)").arg(message).arg(error_code);
+        }
+        else {
+          error_reason = QString("%1 (%2)").arg(reply->errorString()).arg(reply->error());
+        }
+      }
+      else {
+        error_reason = QString("%1 (%2)").arg(reply->errorString()).arg(reply->error());
+      }
+      if (reply->error() == QNetworkReply::ContentAccessDenied ||
+          reply->error() == QNetworkReply::ContentOperationNotPermittedError ||
+          reply->error() == QNetworkReply::AuthenticationRequiredError ||
+          error_code == ScrobbleErrorCode::InvalidSessionKey ||
+          error_code == ScrobbleErrorCode::AuthenticationFailed
+        ){
+        // Session is probably expired
+        Logout();
+        Error(error_reason);
+      }
+      else if (reply->error() == QNetworkReply::ContentNotFoundError) { // Ignore this error
+        Error(error_reason);
+      }
+      else { // Fail
+        Error(error_reason);
+      }
+    }
+    return QByteArray();
+  }
+
+  return data;
+  
+}
+
+void ScrobblingAPI20::UpdateNowPlaying(const Song &song) {
+
+  song_playing_ = song;
+  timestamp_ = QDateTime::currentDateTime().toTime_t();
+
+  if (!IsAuthenticated() || !song.is_metadata_good()) return;
+
+  ParamList params = ParamList()
+    << Param("method", "track.updateNowPlaying")
+    << Param("artist", song.artist())
+    << Param("track", song.title())
+    << Param("album", song.album());
+
+  QNetworkReply *reply = CreateRequest(params);
+  NewClosure(reply, SIGNAL(finished()), this, SLOT(UpdateNowPlayingRequestFinished(QNetworkReply*)), reply);
+
+}
+
+void ScrobblingAPI20::UpdateNowPlayingRequestFinished(QNetworkReply *reply) {
+
+  reply->deleteLater();
+
+  QByteArray data = GetReplyData(reply);
+  if (data.isEmpty()) {
+    return;
+  }
+
+  // TODO
+
+}
+
+void ScrobblingAPI20::Scrobble(const Song &song) {
+
+  if (song.id() != song_playing_.id() || song.url() != song_playing_.url() || !song.is_metadata_good()) return;
+
+  cache()->Add(song, timestamp_);
+
+  if (app_->scrobbler()->IsOffline()) return;
+  
+  if (!IsAuthenticated()) {
+    emit ErrorMessage(QString("Scrobbler %1 is not authenticated!").arg(name_));
+    return;
+  }
+
+  if (!submitted_) {
+    DoInAMinuteOrSo(this, SLOT(Submit()));
+    submitted_ = true;
+  }
+
+}
+
+void ScrobblingAPI20::Submit() {
+
+  qLog(Debug) << __PRETTY_FUNCTION__ << name_;
+
+  submitted_ = false;
+
+  if (!IsEnabled() || !IsAuthenticated() || app_->scrobbler()->IsOffline()) return;
+
+  ParamList params = ParamList()
+    << Param("method", "track.scrobble");
+
+  int i(0);
+  QList<quint64> list;
+  for (ScrobblerCacheItem *item : cache()->List()) {
+    if (item->sent_) continue;
+    item->sent_ = true;
+    if (!batch_) { SendSingleScrobble(item); continue; }
+    i++;
+    list << item->timestamp_;
+    params << Param(QString("%1[%2]").arg("artist").arg(i), item->artist_);
+    params << Param(QString("%1[%2]").arg("album").arg(i), item->album_);
+    params << Param(QString("%1[%2]").arg("track").arg(i), item->song_);
+    params << Param(QString("%1[%2]").arg("timestamp").arg(i), QString::number(item->timestamp_));
+    params << Param(QString("%1[%2]").arg("duration").arg(i), QString::number(item->duration_ / kNsecPerSec));
+    if (!item->albumartist_.isEmpty()) params << Param(QString("%1[%2]").arg("albumArtist").arg(i), item->albumartist_);
+    if (item->track_ > 0) params << Param(QString("%1[%2]").arg(i).arg("trackNumber"), QString::number(item->track_));
+    if (i >= kScrobblesPerRequest) break;
+  }
+
+  if (!batch_ || i <= 0) return;
+
+  QNetworkReply *reply = CreateRequest(params);
+  NewClosure(reply, SIGNAL(finished()), this, SLOT(ScrobbleRequestFinished(QNetworkReply*, QList<quint64>)), reply, list);
+
+}
+
+void ScrobblingAPI20::ScrobbleRequestFinished(QNetworkReply *reply, QList<quint64> list) {
+
+  reply->deleteLater();
+
+  QByteArray data = GetReplyData(reply);
+  if (data.isEmpty()) {
+    cache()->ClearSent(list);
+    return;
+  }
+
+  QJsonObject json_obj = ExtractJsonObj(data);
+  if (json_obj.isEmpty()) {
+    cache()->ClearSent(list);
+    return;
+  }
+
+  if (!json_obj.contains("scrobbles")) {
+    if (json_obj.contains("error")) {
+      int error = json_obj["error"].toInt();
+      Error(QString("Error: %1: %2").arg(QString::number(error)).arg(error));
+    }
+    Error("Json reply from server is missing session.");
+    cache()->ClearSent(list);
+    return;
+  }
+
+  cache()->Flush(list);
+
+  QJsonValue json_scrobbles = json_obj["scrobbles"];
+  if (!json_scrobbles.isObject()) {
+    Error("Json scrobbles is not an object.", json_obj);
+    return;
+  }
+  json_obj = json_scrobbles.toObject();
+  if (json_obj.isEmpty()) {
+    Error("Json scrobbles object is empty.", json_scrobbles);
+    return;
+  }
+  if (!json_obj.contains("@attr") || !json_obj.contains("scrobble")) {
+    Error("Json scrobbles object is missing values.", json_obj);
+    return;
+  }
+
+  QJsonValue json_attr = json_obj["@attr"];
+  if (!json_attr.isObject()) {
+    Error("Json scrobbles attr is not an object.", json_attr);
+    return;
+  }
+  QJsonObject json_obj_attr = json_attr.toObject();
+  if (json_obj_attr.isEmpty()) {
+    Error("Json scrobbles attr is empty.", json_attr);
+    return;
+  }
+  if (!json_obj_attr.contains("accepted") || !json_obj_attr.contains("ignored")) {
+    Error("Json scrobbles attr is missing values.", json_obj_attr);
+    return;
+  }
+  int accepted = json_obj_attr["accepted"].toInt();
+  int ignored = json_obj_attr["ignored"].toInt();
+  qLog(Debug) << name_ << "Scrobbles accepted:" << accepted << "ignored:" << ignored;
+
+  QJsonValue json_scrobble = json_obj["scrobble"];
+  if (!json_scrobble.isArray()) {
+    Error("Json scrobbles scrobble is not array.", json_scrobble);
+    return;
+  }
+  QJsonArray json_array_scrobble = json_scrobble.toArray();
+  if (json_array_scrobble.isEmpty()) {
+    Error("Json scrobbles scrobble array is empty.", json_scrobble);
+    return;
+  }
+  
+  for (const QJsonValue &value : json_array_scrobble) {
+
+    if (!value.isObject()) {
+      Error("Json scrobbles scrobble array value is not an object.", value);
+      continue;
+    }
+    QJsonObject json_track = value.toObject();
+    if (json_track.isEmpty()) {
+      continue;
+    }
+
+    if (!json_track.contains("artist") ||
+        !json_track.contains("album") ||
+        !json_track.contains("albumArtist") ||
+        !json_track.contains("track") ||
+        !json_track.contains("timestamp") ||
+        !json_track.contains("ignoredMessage")
+    ) {
+      Error("Json scrobbles scrobble is missing values.", json_track);
+      return;
+    }
+
+    QJsonValue json_value_artist = json_track["artist"];
+    QJsonValue json_value_album = json_track["album"];
+    QJsonValue json_value_song = json_track["track"];
+    //quint64 timestamp = json_track["timestamp"].toVariant().toULongLong();
+
+    if (!json_value_artist.isObject() || !json_value_album.isObject() || !json_value_song.isObject()) {
+      Error("Json scrobbles scrobble values are not objects.", json_track);
+      continue;
+    }
+
+    QJsonObject json_obj_artist = json_value_artist.toObject();
+    QJsonObject json_obj_album = json_value_album.toObject();
+    QJsonObject json_obj_song = json_value_song.toObject();
+
+    if (json_obj_artist.isEmpty() || json_obj_album.isEmpty() || json_obj_song.isEmpty()) {
+      Error("Json scrobbles scrobble values objects are empty.", json_track);
+      continue;
+    }
+
+    if (!json_obj_artist.contains("#text") || !json_obj_album.contains("#text") || !json_obj_song.contains("#text")) {
+      Error("Json scrobbles scrobble values objects are empty.", json_track);
+      continue;
+    }
+
+    // TODO
+
+ }
+
+}
+
+void ScrobblingAPI20::SendSingleScrobble(ScrobblerCacheItem *item) {
+
+  ParamList params = ParamList()
+    << Param("method", "track.scrobble")
+    << Param("artist", item->artist_)
+    << Param("album", item->album_)
+    << Param("track", item->song_)
+    << Param("timestamp", QString::number(item->timestamp_))
+    << Param("duration", QString::number(item->duration_ / kNsecPerSec));
+
+  if (!item->albumartist_.isEmpty()) params << Param("albumArtist", item->albumartist_);
+  if (item->track_ > 0) params << Param("trackNumber", QString::number(item->track_));
+
+  QNetworkReply *reply = CreateRequest(params);
+  NewClosure(reply, SIGNAL(finished()), this, SLOT(SingleScrobbleRequestFinished(QNetworkReply*, quint64)), reply, item->timestamp_);
+
+}
+
+void ScrobblingAPI20::SingleScrobbleRequestFinished(QNetworkReply *reply, quint64 timestamp) {
+
+  reply->deleteLater();
+
+  ScrobblerCacheItem *item = cache()->Get(timestamp);
+  if (!item) {
+    Error(QString("Received reply for non-existing cache entry %1.").arg(timestamp));
+    return;
+  }
+
+  QByteArray data = GetReplyData(reply);
+  if (data.isEmpty()) {
+    return;
+  }
+
+  QJsonObject json_obj = ExtractJsonObj(data);
+  if (json_obj.isEmpty()) {
+    return;
+  }
+
+  if (!json_obj.contains("scrobbles")) {
+    if (json_obj.contains("error")) {
+      int error = json_obj["error"].toInt();
+      Error(QString("Error: %1: %2").arg(QString::number(error)).arg(error));
+    }
+    Error("Json reply from server is missing session.");
+    return;
+  }
+
+  QJsonValue json_scrobbles = json_obj["scrobbles"];
+  if (!json_scrobbles.isObject()) {
+    Error("Json scrobbles is not an object.", json_obj);
+    return;
+  }
+  json_obj = json_scrobbles.toObject();
+  if (json_obj.isEmpty()) {
+    Error("Json scrobbles object is empty.", json_scrobbles);
+    return;
+  }
+  if (!json_obj.contains("@attr") || !json_obj.contains("scrobble")) {
+    Error("Json scrobbles object is missing values.", json_obj);
+    return;
+  }
+
+  QJsonValue json_attr = json_obj["@attr"];
+  if (!json_attr.isObject()) {
+    Error("Json scrobbles attr is not an object.", json_attr);
+    return;
+  }
+  QJsonObject json_obj_attr = json_attr.toObject();
+  if (json_obj_attr.isEmpty()) {
+    Error("Json scrobbles attr is empty.", json_attr);
+    return;
+  }
+
+  QJsonValue json_scrobble = json_obj["scrobble"];
+  if (!json_scrobble.isObject()) {
+    Error("Json scrobbles scrobble is not an object.", json_scrobble);
+    return;
+  }
+  QJsonObject json_obj_scrobble = json_scrobble.toObject();
+  if (json_obj_scrobble.isEmpty()) {
+    Error("Json scrobbles scrobble is empty.", json_scrobble);
+    return;
+  }
+
+  if (!json_obj_attr.contains("accepted") || !json_obj_attr.contains("ignored")) {
+    Error("Json scrobbles attr is missing values.", json_obj_attr);
+    return;
+  }
+
+  if (!json_obj_scrobble.contains("artist") || !json_obj_scrobble.contains("album") || !json_obj_scrobble.contains("albumArtist") || !json_obj_scrobble.contains("track") || !json_obj_scrobble.contains("timestamp")) {
+    Error("Json scrobbles scrobble is missing values.", json_obj_scrobble);
+    return;
+  }
+
+  int accepted = json_obj_attr["accepted"].toVariant().toInt();
+  if (accepted == 1) {
+    qLog(Debug) << name_ << "Scrobble for" << item->song_ << "accepted";
+  }
+  else {
+    Error(QString("Scrobble for \"%1\" not accepted").arg(item->song_));
+    qLog(Debug) << name_ << json_obj_attr["accepted"];
+  }
+
+  cache()->Remove(timestamp);
+
+}
+
+void ScrobblingAPI20::Love(const Song &song) {
+
+  if (!IsAuthenticated()) app_->scrobbler()->ShowConfig();
+
+  ParamList params = ParamList()
+    << Param("method", "track.love")
+    << Param("artist", song.artist())
+    << Param("track", song.title())
+    << Param("album", song.album());
+
+  QNetworkReply *reply = CreateRequest(params);
+  NewClosure(reply, SIGNAL(finished()), this, SLOT(RequestFinished(QNetworkReply*)), reply);
+
+}
+
+void ScrobblingAPI20::AuthError(QString error) {
+  emit AuthenticationComplete(false, error);
+}
+
+void ScrobblingAPI20::Error(QString error, QVariant debug) {
+
+  qLog(Error) << name_ << error;
+  if (debug.isValid()) qLog(Debug) << debug;
+
+}
+
+QString ScrobblingAPI20::ErrorString(ScrobbleErrorCode error) const {
+
+  switch (error) {
+    case ScrobbleErrorCode::InvalidService:
+      return QString("Invalid service - This service does not exist");
+    case ScrobbleErrorCode::InvalidMethod:
+      return QString("Invalid Method - No method with that name in this package");
+    case ScrobbleErrorCode::AuthenticationFailed:
+      return QString("Authentication Failed - You do not have permissions to access the service");
+    case ScrobbleErrorCode::InvalidFormat:
+      return QString("Invalid format - This service doesn't exist in that format");
+    case ScrobbleErrorCode::InvalidParameters:
+      return QString("Invalid parameters - Your request is missing a required parameter");
+    case ScrobbleErrorCode::InvalidResourceSpecified:
+      return QString("Invalid resource specified");
+    case ScrobbleErrorCode::OperationFailed:
+      return QString("Operation failed - Something else went wrong");
+    case ScrobbleErrorCode::InvalidSessionKey:
+      return QString("Invalid session key - Please re-authenticate");
+    case ScrobbleErrorCode::InvalidApiKey:
+      return QString("Invalid API key - You must be granted a valid key by last.fm");
+    case ScrobbleErrorCode::ServiceOffline:
+      return QString("Service Offline - This service is temporarily offline. Try again later.");
+    case ScrobbleErrorCode::InvalidMethodSignature:
+        return QString("Invalid method signature supplied");
+    case ScrobbleErrorCode::TempError:
+      return QString("There was a temporary error processing your request. Please try again");
+    case ScrobbleErrorCode::SuspendedAPIKey:
+      return QString("Suspended API key - Access for your account has been suspended, please contact Last.fm");
+    case ScrobbleErrorCode::RateLimitExceeded:
+      return QString("Rate limit exceeded - Your IP has made too many requests in a short period");
+    default:
+      return QString("Unknown error");
+  }
+
+}

src/scrobbler/scrobblingapi20.h

@@ -0,0 +1,158 @@
+/*
+ * Strawberry Music Player
+ * Copyright 2018, Jonas Kvinge <jonas@jkvinge.net>
+ *
+ * Strawberry is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Strawberry is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Strawberry.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef SCROBBLINGAPI20_H
+#define SCROBBLINGAPI20_H
+
+#include "config.h"
+
+#include <memory>
+
+#include <QtGlobal>
+#include <QObject>
+#include <QNetworkReply>
+#include <QPair>
+#include <QList>
+#include <QVariant>
+#include <QByteArray>
+#include <QString>
+#include <QJsonObject>
+
+#include "core/song.h"
+#include "scrobblerservice.h"
+#include "scrobblercache.h"
+
+class Application;
+class NetworkAccessManager;
+class LocalRedirectServer;
+class ScrobblerService;
+class ScrobblerCache;
+class ScrobblerCacheItem;
+
+class ScrobblingAPI20 : public ScrobblerService {
+  Q_OBJECT
+
+ public:
+  explicit ScrobblingAPI20(const QString &name, const QString &settings_group, const QString &auth_url, const QString &api_url, const bool batch, Application *app, QObject *parent = nullptr);
+  ~ScrobblingAPI20();
+
+  static const char *kRedirectUrl;
+
+  void ReloadSettings();
+  void LoadSession();
+  
+  virtual NetworkAccessManager *network() = 0;
+  virtual ScrobblerCache *cache() = 0;
+
+  bool IsEnabled() const { return enabled_; }
+  bool IsAuthenticated() const { return !username_.isEmpty() && !session_key_.isEmpty(); }
+  bool IsSubscriber() const { return subscriber_; }
+  bool IsSubmitted() const { return submitted_; }
+  void Submitted() { submitted_ = true; }
+  QString username() const { return username_; }
+
+  void Authenticate();
+  void Logout();
+  void UpdateNowPlaying(const Song &song);
+  void Scrobble(const Song &song);
+  void Submit();
+  void Love(const Song &song);
+
+ signals:
+  void AuthenticationComplete(bool success, QString error = QString());
+
+ public slots:
+  void WriteCache() { cache()->WriteCache(); }
+
+ private slots:
+  void RedirectArrived(LocalRedirectServer *server);
+  void AuthenticateReplyFinished(QNetworkReply *reply);
+  void UpdateNowPlayingRequestFinished(QNetworkReply *reply);
+  void ScrobbleRequestFinished(QNetworkReply *reply, QList<quint64>);
+  void SingleScrobbleRequestFinished(QNetworkReply *reply, quint64 timestamp);
+
+ private:
+
+  enum ScrobbleErrorCode {
+    Unknown = 0,
+    NoError = 1,
+    InvalidService = 2,
+    InvalidMethod = 3,
+    AuthenticationFailed = 4,
+    InvalidFormat = 5,
+    InvalidParameters = 6,
+    InvalidResourceSpecified = 7,
+    OperationFailed = 8,
+    InvalidSessionKey = 9,
+    InvalidApiKey = 10,
+    ServiceOffline = 11,
+    Reserved12 = 12,
+    InvalidMethodSignature = 13,
+    Reserved14 = 14,
+    Reserved15 = 15,
+    TempError = 16,
+    Reserved17 = 17,
+    Reserved18 = 18,
+    Reserved19 = 19,
+    Reserved20 = 20,
+    Reserved21 = 21,
+    Reserved22 = 22,
+    Reserved23 = 23,
+    Reserved24 = 24,
+    Reserved25 = 25,
+    SuspendedAPIKey = 26,
+    Reserved27 = 27,
+    Reserved28 = 28,
+    RateLimitExceeded = 29,
+  };
+
+  static const char *kApiKey;
+  static const char *kSecret;
+  static const int kScrobblesPerRequest;
+
+  QNetworkReply *CreateRequest(const ParamList &request_params);
+  QByteArray GetReplyData(QNetworkReply *reply);
+
+  void RequestSession(QString token);
+  void AuthError(QString error);
+  void SendSingleScrobble(ScrobblerCacheItem *item);
+  void Error(QString error, QVariant debug = QVariant());
+  QString ErrorString(ScrobbleErrorCode error) const;
+
+  QString name_;
+  QString settings_group_;
+  QString auth_url_;
+  QString api_url_;
+  bool batch_;
+
+  Application *app_;
+
+  bool enabled_;
+
+  bool subscriber_;
+  QString username_;
+  QString session_key_;
+
+  bool submitted_;
+  Song song_playing_;
+  quint64 timestamp_;
+
+};
+
+#endif  // SCROBBLINGAPI20_H