Rework mediaplayer support to use mpd

Rework the mediaplayer support to replace the stubbed out app
framework agl-service-mediaplayer binding use with driving mpd
(Media Player Daemon) via the libmpdclient library.  Local file
playback behavior should be equivalent to before in an image
with mpd present and suitably configured.  Bluetooth AVRCP
support is still stubbed out, and will be re-implemented with
followup changes.

Bug-AGL: SPEC-4182

Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Change-Id: Ifdf092b472c271460d0f5e9a8c7d2353904411b2

7 files changed, 832 insertions, 200 deletions

diff --git a/mediaplayer/CMakeLists.txt b/mediaplayer/CMakeLists.txt
index e21b590..3f77b8d 100644
--- a/mediaplayer/CMakeLists.txt
+++ b/mediaplayer/CMakeLists.txt
@@ -3,12 +3,15 @@ CONFIGURE_FILE("qtappfw-mediaplayer.pc.in" "qtappfw-mediaplayer.pc" @ONLY)
 install(FILES ${CMAKE_CURRENT_BINARY_DIR}/qtappfw-mediaplayer.pc
 	DESTINATION ${CMAKE_INSTALL_PREFIX}/lib/pkgconfig)
 
-add_library(qtappfw-mediaplayer SHARED mediaplayer.cpp)
+add_library(qtappfw-mediaplayer SHARED
+	mediaplayer.cpp
+	MediaplayerMpdBackend.cpp
+	MpdEventHandler.cpp)
 
 target_include_directories(qtappfw-mediaplayer PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}")
 target_include_directories(qtappfw-mediaplayer PUBLIC "${CMAKE_INSTALL_INCLUDEDIR}")
 
-target_link_libraries(qtappfw-mediaplayer qtappfw-core)
+target_link_libraries(qtappfw-mediaplayer Qt5::Qml PkgConfig::libmpdclient)
 set_target_properties(qtappfw-mediaplayer PROPERTIES
 	VERSION ${PROJECT_VERSION}
 	SOVERSION 1
diff --git a/mediaplayer/MediaplayerMpdBackend.cpp b/mediaplayer/MediaplayerMpdBackend.cpp
new file mode 100644
index 0000000..c42d18a
--- /dev/null
+++ b/mediaplayer/MediaplayerMpdBackend.cpp
@@ -0,0 +1,284 @@
+/*
+ * Copyright (C) 2022 Konsulko Group
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <QDebug>
+#include "MediaplayerMpdBackend.h"
+#include "MpdEventHandler.h"
+#include "mediaplayer.h"
+
+// Use a 60s timeout on our MPD connection
+// NOTE: The connection is actively poked at a higher frequency than
+//       this to ensure we don't hit the timeout.  The alternatives
+//       are to either open and close a connection for every command,
+//       or try to keep the connection in idle mode when not using it.
+//       The latter is deemed too complicated for our purposes for now,
+//       due to it likely requiring another thread.
+#define MPD_CONNECTION_TIMEOUT	60000
+
+MediaplayerMpdBackend::MediaplayerMpdBackend(Mediaplayer *player, QQmlContext *context, QObject *parent) :
+	QObject(parent),
+	m_player(player)
+{
+	struct mpd_connection *conn = mpd_connection_new(NULL, 0, MPD_CONNECTION_TIMEOUT);
+	if (!conn) {
+		qFatal("Could not create MPD connection");
+	}
+	if (mpd_connection_get_error(conn) != MPD_ERROR_SUCCESS) {
+		qFatal("%s", mpd_connection_get_error_message(conn));
+	}
+	m_mpd_conn = conn;
+
+	// Set up connection keepalive timer
+	m_mpd_conn_timer = new QTimer(this);
+	connect(m_mpd_conn_timer, &QTimer::timeout, this, &MediaplayerMpdBackend::connectionKeepaliveTimeout);
+	m_mpd_conn_timer->start(MPD_CONNECTION_TIMEOUT / 2);
+
+	m_song_pos_timer = new QTimer(this);
+	connect(m_song_pos_timer, &QTimer::timeout, this, &MediaplayerMpdBackend::songPositionTimeout);
+
+	MpdEventHandler *handler = new MpdEventHandler();
+	handler->moveToThread(&m_handlerThread);
+	connect(&m_handlerThread, &QThread::finished, handler, &QObject::deleteLater);
+	connect(this, &MediaplayerMpdBackend::start, handler, &MpdEventHandler::handleEvents);
+
+	// Connect playback state updates from the backend handler thread
+	// so our view of the state is kept in sync with MPD.
+	connect(handler,
+		&MpdEventHandler::playbackStateUpdate,
+		this,
+		&MediaplayerMpdBackend::updatePlaybackState);
+
+	// Connect updates from backend handler thread to parent.
+	// Note that we should not have to explicitly specify the
+	// Qt::QueuedConnection option here since the handler is constructed
+	// by adding a worker object to a QThread and it should be automatic
+	// in that case.
+	connect(handler,
+		&MpdEventHandler::playlistUpdate,
+		player,
+		&Mediaplayer::updatePlaylist);
+	connect(handler,
+		&MpdEventHandler::metadataUpdate,
+		player,
+		&Mediaplayer::updateMetadata);
+
+	m_handlerThread.start();
+
+	// Start event handler worker loop
+	emit start();
+}
+
+MediaplayerMpdBackend::~MediaplayerMpdBackend()
+{
+	m_handlerThread.quit();
+	m_handlerThread.wait();
+
+	m_mpd_conn_timer->stop();
+	delete m_mpd_conn_timer;
+
+	mpd_connection_free(m_mpd_conn);
+}
+
+void MediaplayerMpdBackend::connectionKeepaliveTimeout(void)
+{
+	m_mpd_conn_mutex.lock();
+
+	// Clear any lingering non-fatal errors
+	if (!mpd_connection_clear_error(m_mpd_conn)) {
+		// NOTE: There should likely be an attempt to reconnect here,
+		//       but it definitely would complicate things for all the
+		//       other users.
+		qWarning() << "MPD connection in error state!";
+		m_mpd_conn_mutex.unlock();
+		return;
+	}
+
+	struct mpd_status *status = mpd_run_status(m_mpd_conn);
+	if (!status) {
+		qWarning() << "MPD connection status check failed";
+	} else {
+		mpd_status_free(status);
+	}
+
+	m_mpd_conn_mutex.unlock();
+}
+
+void MediaplayerMpdBackend::songPositionTimeout(void)
+{
+	m_state_mutex.lock();
+
+	if (m_playing) {
+		// Instead of the expense of repeatedly calling mpd_run_status,
+		// provide our own elapsed time.  In practice this seems
+		// sufficient for reasonable behavior in the application UI, and
+		// it is what seems recommended for MPD client implementations.
+		m_song_pos_ms += 250;
+		QVariantMap metadata;
+		metadata["position"] = m_song_pos_ms;
+		m_player->updateMetadata(metadata);
+	}
+
+	m_state_mutex.unlock();
+}
+
+void MediaplayerMpdBackend::updatePlaybackState(int queue_pos, int song_pos_ms, bool state)
+{
+	m_state_mutex.lock();
+
+	m_queue_pos = queue_pos;
+	m_song_pos_ms = song_pos_ms;
+	if (m_playing != state) {
+		if (state) {
+			// Start position timer
+			m_song_pos_timer->start(250);
+		} else {
+			// Stop position timer
+			m_song_pos_timer->stop();
+			//m_song_pos_ms = 0;
+		}
+	}
+	m_playing = state;
+
+	m_state_mutex.unlock();
+}
+
+// Control methods
+
+void MediaplayerMpdBackend::play()
+{
+	m_mpd_conn_mutex.lock();
+
+	m_state_mutex.lock();
+	if (!m_playing) {
+		mpd_run_play(m_mpd_conn);
+	}
+	m_state_mutex.unlock();
+
+	m_mpd_conn_mutex.unlock();
+}
+
+void MediaplayerMpdBackend::pause()
+{
+	m_mpd_conn_mutex.lock();
+
+	m_state_mutex.lock();
+	if (m_playing) {
+		mpd_run_pause(m_mpd_conn, true);
+	}
+	m_state_mutex.unlock();
+
+	m_mpd_conn_mutex.unlock();
+}
+
+void MediaplayerMpdBackend::previous()
+{
+	m_mpd_conn_mutex.lock();
+
+	// MPD only allows next/previous if playing
+	m_state_mutex.lock();
+	if (m_playing) {
+		mpd_run_previous(m_mpd_conn);
+	}
+	m_state_mutex.unlock();
+
+	m_mpd_conn_mutex.unlock();
+}
+
+void MediaplayerMpdBackend::next()
+{
+	m_mpd_conn_mutex.lock();
+
+	// MPD only allows next/previous if playing
+	m_state_mutex.lock();
+	if (m_playing) {
+		mpd_run_next(m_mpd_conn);
+	}
+	m_state_mutex.unlock();
+
+	m_mpd_conn_mutex.unlock();
+}
+
+void MediaplayerMpdBackend::seek(int milliseconds)
+{
+	m_mpd_conn_mutex.lock();
+
+	float t = milliseconds;
+	t /= 1000.0;
+	mpd_run_seek_current(m_mpd_conn, t, false);
+
+	m_mpd_conn_mutex.unlock();
+}
+
+// Relative to current position
+void MediaplayerMpdBackend::fastforward(int milliseconds)
+{
+	m_mpd_conn_mutex.lock();
+
+	float t = milliseconds;
+	t /= 1000.0;
+	mpd_run_seek_current(m_mpd_conn, t, true);
+
+	m_mpd_conn_mutex.unlock();
+}
+
+// Relative to current position
+void MediaplayerMpdBackend::rewind(int milliseconds)
+{
+	m_mpd_conn_mutex.lock();
+
+	float t = -milliseconds;
+	t /= 1000.0;
+	mpd_run_seek_current(m_mpd_conn, t, true);
+
+	m_mpd_conn_mutex.unlock();
+}
+
+void MediaplayerMpdBackend::picktrack(int track)
+{
+	m_mpd_conn_mutex.lock();
+
+	if (track >= 0) {
+		mpd_run_play_pos(m_mpd_conn, track);
+	}
+
+	m_mpd_conn_mutex.unlock();
+}
+
+void MediaplayerMpdBackend::volume(int volume)
+{
+	// Not implemented
+}
+
+void MediaplayerMpdBackend::loop(QString state)
+{
+	m_mpd_conn_mutex.lock();
+
+	// Song:
+	// mpd_run_single_state(m_mpd_conn, MPD_SINGLE_ON)
+	// mpd_run_repeat(m_mpd_conn, true) to loop
+	//
+	// Playlist:
+	// mpd_run_single_state(m_mpd_conn, MPD_SINGLE_OFF) (default)
+	// mpd_run_repeat(m_mpd_conn, true) to loop
+
+	if (state == "playlist") {
+		mpd_run_repeat(m_mpd_conn, true);
+	} else {
+		mpd_run_repeat(m_mpd_conn, false);
+	}
+
+	m_mpd_conn_mutex.unlock();
+}
diff --git a/mediaplayer/MediaplayerMpdBackend.h b/mediaplayer/MediaplayerMpdBackend.h
new file mode 100644
index 0000000..b181fda
--- /dev/null
+++ b/mediaplayer/MediaplayerMpdBackend.h
@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2022 Konsulko Group
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef MEDIAPLAYER_MPD_BACKEND_H
+#define MEDIAPLAYER_MPD_BACKEND_H
+
+#include <QObject>
+#include <QtQml/QQmlContext>
+#include <QThread>
+#include <QTimer>
+#include <QMutex>
+#include <mpd/client.h>
+#include "mediaplayer.h"
+
+class MediaplayerMpdBackend : public QObject
+{
+	Q_OBJECT
+
+public:
+	explicit MediaplayerMpdBackend(Mediaplayer *player, QQmlContext *context, QObject * parent = Q_NULLPTR);
+	virtual ~MediaplayerMpdBackend();
+
+	void play();
+	void pause();
+	void previous();
+	void next();
+	void seek(int);
+	void fastforward(int);
+	void rewind(int);
+	void picktrack(int);
+	void volume(int);
+	void loop(QString);
+
+signals:
+	void start(void);
+
+private:
+	Mediaplayer *m_player;
+
+	// MPD connection for sending commands
+	struct mpd_connection *m_mpd_conn;
+	QTimer *m_mpd_conn_timer;
+	QMutex m_mpd_conn_mutex;
+
+	int m_queue_pos = -1;
+	int m_song_pos_ms = 0;
+	bool m_playing = false;
+	QTimer *m_song_pos_timer;
+	QMutex m_state_mutex;
+
+	QThread m_handlerThread;
+
+private slots:
+	void connectionKeepaliveTimeout(void);
+	void songPositionTimeout(void);
+        void updatePlaybackState(int queue_pos, int song_pos_ms, bool state);
+};
+
+#endif // MEDIAPLAYER_MPD_BACKEND_H
diff --git a/mediaplayer/MpdEventHandler.cpp b/mediaplayer/MpdEventHandler.cpp
new file mode 100644
index 0000000..40d2999
--- /dev/null
+++ b/mediaplayer/MpdEventHandler.cpp
@@ -0,0 +1,309 @@
+/*
+ * Copyright (C) 2022 Konsulko Group
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <QDebug>
+#include "MpdEventHandler.h"
+
+MpdEventHandler::MpdEventHandler(QObject *parent) :
+	QObject(parent)
+{
+	// NOTE: Not specifying a timeout here as it is assumed to be long
+	//       enough that we won't timeout in the brief intervals when
+	//       switching in and out of idle mode.
+	struct mpd_connection *conn = mpd_connection_new(NULL, 0, 0);
+	if (!conn) {
+		qFatal("Could not create MPD connection");
+	}
+	if (mpd_connection_get_error(conn) != MPD_ERROR_SUCCESS) {
+		qFatal("%s", mpd_connection_get_error_message(conn));
+	}
+	m_mpd_conn = conn;
+}
+
+MpdEventHandler::~MpdEventHandler()
+{
+	mpd_connection_free(m_mpd_conn);
+}
+
+void MpdEventHandler::handleEvents(void)
+{
+	bool done = false;
+	enum mpd_idle mask = (enum mpd_idle)(MPD_IDLE_DATABASE|MPD_IDLE_QUEUE|MPD_IDLE_PLAYER);
+	enum mpd_idle events;
+	while (!done) {
+		// Wait for an event
+		events = mpd_run_idle_mask(m_mpd_conn, mask);
+
+		// NOTE: Realistically should be checking the result of
+		//       mpd_connection_get_error here, but handling it will
+		//       complicate things significantly.
+
+		// handle the events
+		if (events & MPD_IDLE_DATABASE) {
+			handleDatabaseEvent();
+		}
+		else if (events & MPD_IDLE_QUEUE) {
+			handleQueueEvent();
+		}
+		else if (events & MPD_IDLE_PLAYER) {
+			handlePlayerEvent();
+		}
+	}
+
+	qDebug() << "MpdEventHandler::handleEvents: exit";
+}
+
+void MpdEventHandler::handleDatabaseEvent(void)
+{
+	// Maybe clear queue here?
+	//mpd_run_delete_range(m_mpd_con, 0, UINT_MAX);
+
+	if(!mpd_run_add(m_mpd_conn, "/")) {
+		qWarning() << "mpd_run_add failed";
+	}
+}
+
+void MpdEventHandler::handleQueueEvent(void)
+{
+	QVariantList playlist;
+	bool done = false;
+	struct mpd_entity *entity;
+	mpd_send_list_queue_meta(m_mpd_conn);
+	do {
+		entity = mpd_recv_entity(m_mpd_conn);
+		if (!entity) {
+			enum mpd_error error = mpd_connection_get_error(m_mpd_conn);
+			if (error == MPD_ERROR_SUCCESS)
+				done = true;
+			break;
+		}
+		if (mpd_entity_get_type(entity) != MPD_ENTITY_TYPE_SONG) {
+			mpd_entity_free(entity);
+			continue;
+		}
+		const struct mpd_song *song = mpd_entity_get_song(entity);
+		QString title(mpd_song_get_tag(song, MPD_TAG_TITLE, 0));
+		QString artist(mpd_song_get_tag(song, MPD_TAG_ARTIST, 0));
+		QString album(mpd_song_get_tag(song, MPD_TAG_ALBUM, 0));
+		QString genre(mpd_song_get_tag(song, MPD_TAG_GENRE, 0));
+		QString uri(mpd_song_get_uri(song));
+		int pos = mpd_song_get_pos(song);
+		//qDebug() << "Queue[" << pos << "]: " << artist << " - " << title << " / " << album << ", genre " << genre;
+
+		QVariantMap track;
+		track["title"] = title;
+		track["artist"] = artist;
+		track["album"] = album;
+		track["genre"] = genre;
+		track["index"] = pos;
+		track["duration"] = mpd_song_get_duration_ms(song);
+		track["path"] = uri;
+		playlist.append(track);
+
+		mpd_entity_free(entity);
+	} while(!done);
+
+	if (done) {
+		QVariantMap metadata;
+		metadata["list"] = playlist;
+
+		emit playlistUpdate(metadata);
+	}
+}
+
+void MpdEventHandler::handlePlayerEvent(void)
+{
+	int pos = -1;
+	QString uri;
+	QVariantMap track;
+	QVariantMap metadata;
+	struct mpd_song* song = mpd_run_current_song(m_mpd_conn);
+	if (song) {
+		QString title(mpd_song_get_tag(song, MPD_TAG_TITLE, 0));
+		QString artist(mpd_song_get_tag(song, MPD_TAG_ARTIST, 0));
+		QString album(mpd_song_get_tag(song, MPD_TAG_ALBUM, 0));
+		QString genre(mpd_song_get_tag(song, MPD_TAG_GENRE, 0));
+		pos = mpd_song_get_pos(song);
+		uri = mpd_song_get_uri(song);
+		//qDebug() << "Current song[" << pos << "]: " << artist << " - " << title << " / " << album << ", genre " << genre;
+
+		track["title"] = title;
+		track["artist"] = artist;
+		track["album"] = album;
+		track["genre"] = genre;
+		track["index"] = pos;
+		track["duration"] = mpd_song_get_duration_ms(song);
+		track["path"] = uri;
+		mpd_song_free(song);
+
+		metadata["track"] = track;
+	}
+	// NOTE:
+	// It may make sense to check status first, and then try to handle the
+	// no song + stopped case at the end of the queue to trigger a move to
+	// the top of the playlist in the UI if that is deemed desirable (the
+	// old binding does not seem to).  However, this may prove a bit
+	// complicated if triggering stop instead of pause is done to trigger
+	// corking in WirePlumber...
+
+	struct mpd_status *status = mpd_run_status(m_mpd_conn);
+
+	int elapsed_ms = mpd_status_get_elapsed_ms(status);
+	metadata["position"] = elapsed_ms;
+
+	int volume = mpd_status_get_volume(status);
+	metadata["volume"] = volume == -1 ? 0 : volume;
+
+	// NOTE: current UI client user does not care about paused vs stopped,
+	//       and the old binding did not differentiate in its responses,
+	//       so do not do so either for now.
+	enum mpd_state state = mpd_status_get_state(status);
+	QString status_name("stopped");
+	if (state ==  MPD_STATE_PLAY)
+		status_name = "playing";
+	metadata["status"] = status_name;
+
+	mpd_status_free(status);
+
+	// For UI
+	emit metadataUpdate(metadata);
+
+	// For backend state tracking
+	emit playbackStateUpdate(pos, elapsed_ms, (state == MPD_STATE_PLAY));
+
+	if (uri.size()) {
+		// Send album art to UI as a separate update.
+		// This avoids things being out of sync than delaying while
+		// the art is is read.
+		// NOTE: Some form of caching might be desirable here.
+		QByteArray buffer;
+		QString mime_type;
+		if (getSongArt(uri, buffer, mime_type) && mime_type.size()) {
+			QString image_base64(buffer.toBase64());
+			QString mime_type_header("data:");
+			mime_type_header += mime_type;
+			mime_type_header += ";base64,";
+			image_base64.prepend(mime_type_header);
+
+			// Re-use metadata map...
+			track["image"] = image_base64;
+			metadata["track"] = track;
+
+			// ...but clear out the ephemeral metadata
+			metadata.remove("position");
+			metadata.remove("status");
+			metadata.remove("volume");
+
+			// Update UI
+			emit metadataUpdate(metadata);
+		}
+	}
+}
+
+bool MpdEventHandler::getSongArt(const QString &path, QByteArray &buffer, QString &type)
+{
+	bool rc = false;
+	unsigned pic_offset = 0;
+	unsigned pic_size = 0;
+
+	QByteArray path_ba = path.toLocal8Bit();
+	const char *path_cstr = path_ba.data();
+
+	bool first = true;
+	do {
+		QString pic_offset_str = QString::number(pic_offset);
+		QByteArray pic_offset_ba = pic_offset_str.toLocal8Bit();
+		const char *pic_offset_cstr = pic_offset_ba.data();
+
+		if (!mpd_send_command(m_mpd_conn, "readpicture", path_cstr, pic_offset_cstr, NULL)) {
+			if (mpd_connection_get_error(m_mpd_conn) != MPD_ERROR_SUCCESS)
+				goto conn_error;
+		}
+		struct mpd_pair *pair = mpd_recv_pair_named(m_mpd_conn, "size");
+		if (!pair) {
+			if (first) {
+				// No art, exit
+				break;
+			}
+
+			if (mpd_connection_get_error(m_mpd_conn) != MPD_ERROR_SUCCESS)
+				goto conn_error;
+		}
+		pic_size = QString(pair->value).toInt();
+		mpd_return_pair(m_mpd_conn, pair);
+
+		pair = mpd_recv_pair_named(m_mpd_conn, "type");
+		if (!pair) {
+			// check for error
+		}
+		QString mime_type(pair->value);
+		mpd_return_pair(m_mpd_conn, pair);
+		if (first) {
+			if (mime_type.size()) {
+				type = mime_type;
+			} else {
+				break;
+			}
+			first = false;
+		}
+
+		pair = mpd_recv_pair_named(m_mpd_conn, "binary");
+		if (!pair) {
+			if (mpd_connection_get_error(m_mpd_conn) != MPD_ERROR_SUCCESS)
+				goto conn_error;
+		}
+
+		unsigned chunk_size = QString(pair->value).toInt();
+		mpd_return_pair(m_mpd_conn, pair);
+
+		if (!chunk_size)
+			break;
+
+		char *buf = new (std::nothrow) char[chunk_size];
+		if (!buf)
+			goto conn_error;
+
+		if (!mpd_recv_binary(m_mpd_conn, buf, chunk_size)) {
+			if (mpd_connection_get_error(m_mpd_conn) != MPD_ERROR_SUCCESS) {
+				delete[] buf;
+				goto conn_error;
+			}
+		}
+
+		if (!mpd_response_finish(m_mpd_conn)) {
+			if (mpd_connection_get_error(m_mpd_conn) != MPD_ERROR_SUCCESS) {
+				delete[] buf;
+				goto conn_error;
+			}
+		}
+
+		buffer.append(buf, chunk_size);
+		delete[] buf;
+
+		pic_offset += chunk_size;
+
+	} while (pic_offset < pic_size);
+
+conn_error:
+	if (pic_offset == pic_size) {
+		rc = true;
+	} else {
+		// Don't pass garbage to caller
+		buffer.clear();
+	}
+
+	return rc;
+}
diff --git a/mediaplayer/MpdEventHandler.h b/mediaplayer/MpdEventHandler.h
new file mode 100644
index 0000000..fcd6155
--- /dev/null
+++ b/mediaplayer/MpdEventHandler.h
@@ -0,0 +1,55 @@
+/*
+ * Copyright (C) 2022 Konsulko Group
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef MPD_EVENT_HANDLER_H
+#define MPD_EVENT_HANDLER_H
+
+#include <QObject>
+//#include <QThread>
+//#include <QTimer>
+//#include <QMutex>
+#include <mpd/client.h>
+
+// Use a 60s timeout on our MPD connection
+#define MPD_CONNECTION_TIMEOUT	60000
+
+class MpdEventHandler : public QObject
+{
+	Q_OBJECT
+
+public:
+	explicit MpdEventHandler(QObject *parent = nullptr);
+	virtual ~MpdEventHandler();
+
+public slots:
+	void handleEvents(void);
+
+signals:
+	void playbackStateUpdate(int queue_pos, int song_pos_ms, bool state);
+        void playlistUpdate(QVariantMap playlist);
+        void metadataUpdate(QVariantMap metadata);
+
+private:
+	void handleDatabaseEvent(void);
+	void handleQueueEvent(void);
+	void handlePlayerEvent(void);
+
+	bool getSongArt(const QString &path, QByteArray &buffer, QString &type);
+
+	struct mpd_connection *m_mpd_conn;
+};
+
+#endif // MPD_EVENT_HANDLER_H
diff --git a/mediaplayer/mediaplayer.cpp b/mediaplayer/mediaplayer.cpp
index c578145..f6a9cbd 100644
--- a/mediaplayer/mediaplayer.cpp
+++ b/mediaplayer/mediaplayer.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2018-2020 Konsulko Group
+ * Copyright (C) 2018-2020,2022 Konsulko Group
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,37 +15,34 @@
  */
 
 #include <QDebug>
+#include <QJsonObject>
 
-#include "callmessage.h"
-#include "eventmessage.h"
-#include "messageengine.h"
-#include "messagefactory.h"
-#include "messageenginefactory.h"
 #include "mediaplayer.h"
+#include "MediaplayerMpdBackend.h"
 
 
 Playlist::Playlist(QVariantMap &item)
 {
-    m_index = item["index"].toInt();
-    m_duration = item["duration"].toInt();
-    m_genre = item["genre"].toString();
-    m_path = item["path"].toString();
-    m_title = item["title"].toString();
-    m_album = item["album"].toString();
-    m_artist = item["artist"].toString();
+	m_index = item["index"].toInt();
+	m_duration = item["duration"].toInt();
+	m_genre = item["genre"].toString();
+	m_path = item["path"].toString();
+	m_title = item["title"].toString();
+	m_album = item["album"].toString();
+	m_artist = item["artist"].toString();
 }
 
 Playlist::~Playlist() {}
 
-Mediaplayer::Mediaplayer (QUrl &url, QQmlContext *context, QObject * parent) :
-    QObject(parent)
+Mediaplayer::Mediaplayer (QQmlContext *context, QObject * parent) :
+	QObject(parent)
 {
-    m_mloop = MessageEngineFactory::getInstance().getMessageEngine(url);
-    m_context = context;
-    m_context->setContextProperty("MediaplayerModel", QVariant::fromValue(m_playlist));
-    QObject::connect(m_mloop.get(), &MessageEngine::connected, this, &Mediaplayer::onConnected);
-    QObject::connect(m_mloop.get(), &MessageEngine::disconnected, this, &Mediaplayer::onDisconnected);
-    QObject::connect(m_mloop.get(), &MessageEngine::messageReceived, this, &Mediaplayer::onMessageReceived);
+	m_context = context;
+	m_context->setContextProperty("MediaplayerModel", QVariant::fromValue(m_playlist));
+
+	m_backend = new MediaplayerMpdBackend(this, context);
+	if (!m_backend)
+		qFatal("Could not create MediaPlayerBackend");
 }
 
 Mediaplayer::~Mediaplayer()
@@ -56,207 +53,129 @@ Mediaplayer::~Mediaplayer()
 
 void Mediaplayer::updatePlaylist(QVariantMap playlist)
 {
-    QVariantList list = playlist["list"].toList();
+	QVariantList list = playlist["list"].toList();
 
-    m_playlist.clear();
+	m_playlist.clear();
 
-    for (auto i : list) {
-        QVariantMap item = qvariant_cast<QVariantMap>(i);
-        m_playlist.append(new Playlist(item));
-    }
+	for (auto i : list) {
+		QVariantMap item = qvariant_cast<QVariantMap>(i);
+		m_playlist.append(new Playlist(item));
+	}
 
-    if (m_playlist.count() == 0) {
-        QVariantMap tmp, track;
+	if (m_playlist.count() == 0) {
+		QVariantMap tmp, track;
 
-        track.insert("title", "");
-        track.insert("artist", "");
-        track.insert("album", "");
-        track.insert("duration", 0);
+		track.insert("title", "");
+		track.insert("artist", "");
+		track.insert("album", "");
+		track.insert("duration", 0);
 
-        tmp.insert("position", 0);
-        tmp.insert("track", track);
+		tmp.insert("position", 0);
+		tmp.insert("track", track);
 
-        // clear metadata in UI
-        m_context->setContextProperty("AlbumArt", "");
-        emit metadataChanged(tmp);
-    }
+		// clear metadata in UI
+		m_context->setContextProperty("AlbumArt", "");
+		emit metadataChanged(tmp);
+	}
 
-    // Refresh model
-    m_context->setContextProperty("MediaplayerModel", QVariant::fromValue(m_playlist));
+	// Refresh model
+	m_context->setContextProperty("MediaplayerModel", QVariant::fromValue(m_playlist));
 }
 
-// Control Verb methods
-
-void Mediaplayer::control(QString control, QJsonObject parameter)
+void Mediaplayer::updateMetadata(QVariantMap metadata)
 {
-    std::unique_ptr<Message> msg = MessageFactory::getInstance().createOutboundMessage(MessageId::Call);
-    if (!msg)
-        return;
+	if (metadata.contains("track")) {
+		QVariantMap track = metadata.value("track").toMap();
 
-    CallMessage* mpmsg = static_cast<CallMessage*>(msg.get());
-    parameter.insert("value", control);
+		if (track.contains("image")) {
+			m_context->setContextProperty("AlbumArt",
+						      QVariant::fromValue(track.value("image")));
+		}
+ 
+		if (!track.contains("artist")) {
+			track.insert("artist", "");
+			metadata["track"] = track;
+		}
+ 
+		if (!track.contains("album")) {
+			track.insert("album", "");
+			metadata["track"] = track;
+		}
+	}
 
-    mpmsg->createRequest("mediaplayer", "controls", parameter);
-    m_mloop->sendMessage(std::move(msg));
+	emit metadataChanged(metadata);
 }
 
+// Control methods
 
-void Mediaplayer::control(QString control)
+// For backwards compatibility
+void Mediaplayer::disconnect()
 {
-    QJsonObject parameter;
+	disconnectBluetooth();
+}
 
-    Mediaplayer::control(control, parameter);
+// For backwards compatibility
+void Mediaplayer::connect()
+{
+	connectBluetooth();
 }
 
-void Mediaplayer::disconnect()
+void Mediaplayer::disconnectBluetooth()
 {
-    control("disconnect");
+	// Disconnect from Bluetooth media
 }
 
-void Mediaplayer::connect()
+void Mediaplayer::connectBluetooth()
 {
-    control("connect");
+	// Connect to Bluetooth media
 }
+
 void Mediaplayer::play()
 {
-    control("play");
+	m_backend->play();
 }
 
 void Mediaplayer::pause()
 {
-    control("pause");
+	m_backend->pause();
 }
 
 void Mediaplayer::previous()
 {
-    control("previous");
+	m_backend->previous();
 }
 
 void Mediaplayer::next()
 {
-    control("next");
+	m_backend->next();
 }
 
 void Mediaplayer::seek(int milliseconds)
 {
-    QJsonObject parameter;
-    parameter.insert("position", QString::number(milliseconds));
-
-    control("seek", parameter);
+	m_backend->seek(milliseconds);
 }
 
 void Mediaplayer::fastforward(int milliseconds)
 {
-    QJsonObject parameter;
-    parameter.insert("position", QString::number(milliseconds));
-
-    control("fast-forward", parameter);
+	m_backend->fastforward(milliseconds);
 }
 
 void Mediaplayer::rewind(int milliseconds)
 {
-    QJsonObject parameter;
-    parameter.insert("position", QString::number(milliseconds));
-
-    control("rewind", parameter);
+	m_backend->rewind(milliseconds);
 }
 
 void Mediaplayer::picktrack(int track)
 {
-    QJsonObject parameter;
-    parameter.insert("index", QString::number(track));
-
-    control("pick-track", parameter);
+	m_backend->picktrack(track);
 }
 
 void Mediaplayer::volume(int volume)
 {
-    QJsonObject parameter;
-    parameter.insert("volume", QString(volume));
-
-    control("volume", parameter);
+	m_backend->volume(volume);
 }
 
 void Mediaplayer::loop(QString state)
 {
-    QJsonObject parameter;
-    parameter.insert("state", state);
-
-    control("loop", parameter);
-}
-
-void Mediaplayer::onConnected()
-{
-    QStringListIterator eventIterator(events);
-
-    while (eventIterator.hasNext()) {
-        std::unique_ptr<Message> msg = MessageFactory::getInstance().createOutboundMessage(MessageId::Call);
-        if (!msg)
-            return;
-
-        CallMessage* mpmsg = static_cast<CallMessage*>(msg.get());
-        QJsonObject parameter;
-        parameter.insert("value", eventIterator.next());
-        mpmsg->createRequest("mediaplayer", "subscribe", parameter);
-        m_mloop->sendMessage(std::move(msg));
-    }
-}
-
-void Mediaplayer::onDisconnected()
-{
-    QStringListIterator eventIterator(events);
-
-    while (eventIterator.hasNext()) {
-        std::unique_ptr<Message> msg = MessageFactory::getInstance().createOutboundMessage(MessageId::Call);
-        if (!msg)
-            return;
-
-	CallMessage* mpmsg = static_cast<CallMessage*>(msg.get());
-        QJsonObject parameter;
-        parameter.insert("value", eventIterator.next());
-        mpmsg->createRequest("mediaplayer", "unsubscribe", parameter);
-        m_mloop->sendMessage(std::move(msg));
-    }
-}
-
-void Mediaplayer::onMessageReceived(std::shared_ptr<Message> msg)
-{
-    if (!msg)
-        return;
-
-    if (msg->isEvent()){
-        std::shared_ptr<EventMessage> emsg = std::static_pointer_cast<EventMessage>(msg);
-        QString ename = emsg->eventName();
-        QString eapi = emsg->eventApi();
-        QJsonObject data = emsg->eventData();
-        if (eapi != "mediaplayer")
-            return;
-
-        if (ename == "playlist") {
-            updatePlaylist(data.toVariantMap());
-        } else if (ename == "metadata") {
-            QVariantMap map = data.toVariantMap();
-
-                if (map.contains("track")) {
-                    QVariantMap track = map.value("track").toMap();
-
-                    if (track.contains("image")) {
-                        m_context->setContextProperty("AlbumArt",
-                            QVariant::fromValue(track.value("image")));
-                    }
-
-                    if (!track.contains("artist")) {
-                        track.insert("artist", "");
-                        map["track"] = track;
-                    }
-
-                    if (!track.contains("album")) {
-                        track.insert("album", "");
-                        map["track"] = track;
-                    }
-                }
-
-                emit metadataChanged(map);
-            }
-        }
+	m_backend->loop(state);
 }
diff --git a/mediaplayer/mediaplayer.h b/mediaplayer/mediaplayer.h
index 3d53a24..9afe6c6 100644
--- a/mediaplayer/mediaplayer.h
+++ b/mediaplayer/mediaplayer.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2018-2020 Konsulko Group
+ * Copyright (C) 2018-2020,2022 Konsulko Group
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,29 +17,25 @@
 #ifndef MEDIAPLAYER_H
 #define MEDIAPLAYER_H
 
-#include <memory>
 #include <QObject>
 #include <QtQml/QQmlContext>
 #include <QtQml/QQmlListProperty>
 
-class MessageEngine;
-class Message;
-
 class Playlist : public QObject
 {
-    Q_OBJECT
+	Q_OBJECT
 
-    Q_PROPERTY(int index READ index NOTIFY indexChanged)
-    Q_PROPERTY(int duration READ duration NOTIFY durationChanged)
-    Q_PROPERTY(QString path READ path NOTIFY pathChanged)
+	Q_PROPERTY(int index READ index NOTIFY indexChanged)
+	Q_PROPERTY(int duration READ duration NOTIFY durationChanged)
+	Q_PROPERTY(QString path READ path NOTIFY pathChanged)
 
-    // METADATA FIELDS
-    Q_PROPERTY(QString title READ title NOTIFY titleChanged)
-    Q_PROPERTY(QString album READ album NOTIFY albumChanged)
-    Q_PROPERTY(QString artist READ artist NOTIFY artistChanged)
-    Q_PROPERTY(QString genre READ genre NOTIFY genreChanged)
+	// METADATA FIELDS
+	Q_PROPERTY(QString title READ title NOTIFY titleChanged)
+	Q_PROPERTY(QString album READ album NOTIFY albumChanged)
+	Q_PROPERTY(QString artist READ artist NOTIFY artistChanged)
+	Q_PROPERTY(QString genre READ genre NOTIFY genreChanged)
 
-    public:
+public:
         explicit Playlist(QVariantMap& item);
         virtual ~Playlist();
 
@@ -54,7 +50,7 @@ class Playlist : public QObject
         QString artist() { return m_artist; };
         QString genre() { return m_genre; };
 
-    signals:
+signals:
         void indexChanged();
         void durationChanged();
         void pathChanged();
@@ -63,22 +59,26 @@ class Playlist : public QObject
         void artistChanged();
         void genreChanged();
 
-    private:
+private:
         int m_index, m_duration;
         QString m_path, m_title, m_album, m_artist, m_genre;
 };
 
+class MediaplayerMpdBackend;
+
 class Mediaplayer : public QObject
 {
-    Q_OBJECT
+	Q_OBJECT
 
-    public:
-        explicit Mediaplayer(QUrl &url, QQmlContext *context, QObject * parent = Q_NULLPTR);
+public:
+        explicit Mediaplayer(QQmlContext *context, QObject * parent = Q_NULLPTR);
         virtual ~Mediaplayer();
 
         // controls
-        Q_INVOKABLE void disconnect();
         Q_INVOKABLE void connect();
+        Q_INVOKABLE void disconnect();
+        Q_INVOKABLE void connectBluetooth();
+        Q_INVOKABLE void disconnectBluetooth();
         Q_INVOKABLE void play();
         Q_INVOKABLE void pause();
         Q_INVOKABLE void previous();
@@ -90,27 +90,17 @@ class Mediaplayer : public QObject
         Q_INVOKABLE void volume(int);
         Q_INVOKABLE void loop(QString);
 
+public slots:
         void updatePlaylist(QVariantMap playlist);
+        void updateMetadata(QVariantMap metadata);
 
-    signals:
+signals:
         void metadataChanged(QVariantMap metadata);
 
-    private:
-        std::shared_ptr<MessageEngine> m_mloop;
+private:
         QQmlContext *m_context;
         QList<QObject *> m_playlist;
-
-        void control(QString, QJsonObject);
-        void control(QString);
-
-        void onConnected();
-        void onDisconnected();
-        void onMessageReceived(std::shared_ptr<Message>);
-
-        const QStringList events {
-            "playlist",
-            "metadata",
-        };
+	MediaplayerMpdBackend *m_backend;
 };
 
 #endif // MEDIAPLAYER_H