big change: a new abstract BluetoothWatch class

1 files changed, 176 insertions, 0 deletions

diff --git a/libsowatchbt/bluetoothwatch.cpp b/libsowatchbt/bluetoothwatch.cpp
new file mode 100644
index 0000000..d977b67
--- /dev/null
+++ b/libsowatchbt/bluetoothwatch.cpp
@@ -0,0 +1,176 @@
+#include "bluetoothwatch.h"
+
+using namespace sowatch;
+QTM_USE_NAMESPACE
+
+const int BluetoothWatch::connectRetryTimes[] = {
+	5, 10, 30, 60, 120, 300
+};
+
+BluetoothWatch::BluetoothWatch(const QBluetoothAddress& address, QObject *parent)
+	: Watch(parent),
+      _localDev(new QBluetoothLocalDevice(this)),
+      _address(address),
+	  _socket(0),
+      _connected(false),
+      _connectRetries(0),
+	  _connectTimer(new QTimer(this)),
+	  _connectAlignedTimer(new QSystemAlignedTimer(this))
+{
+	_connectTimer->setSingleShot(true);
+	_connectAlignedTimer->setSingleShot(true);
+
+	connect(_connectTimer, SIGNAL(timeout()), SLOT(handleConnectTimer()));
+	connect(_connectAlignedTimer, SIGNAL(timeout()), SLOT(handleConnectTimer()));
+	connect(_localDev, SIGNAL(hostModeStateChanged(QBluetoothLocalDevice::HostMode)),
+	        SLOT(handleLocalDevModeChanged(QBluetoothLocalDevice::HostMode)));
+
+	// Check to see if we can connect right away
+	if (_localDev->isValid() &&
+	        _localDev->hostMode() != QBluetoothLocalDevice::HostPoweredOff) {
+		// Do an initial connection attempt after a short delay
+		// (To give time for other plugins to initialize, etc.)
+		scheduleConnect();
+	} else {
+		qDebug() << "Not starting MetaWatch connection because BT is off";
+	}
+}
+
+BluetoothWatch::~BluetoothWatch()
+{
+	if (_socket) {
+		_socket->close();
+		delete _socket;
+	}
+}
+
+bool BluetoothWatch::isConnected() const
+{
+	return _connected;
+}
+
+void BluetoothWatch::scheduleConnect()
+{
+	if (_connected ||
+	        _connectAlignedTimer->isActive() || _connectTimer->isActive()) {
+		// Already connected or already scheduled to connect.
+		return;
+	}
+
+	_connectRetries = 0;
+	_connectTimer->start(100);
+}
+
+void BluetoothWatch::scheduleRetryConnect()
+{
+	if (_connected ||
+	        _connectAlignedTimer->isActive() || _connectTimer->isActive()) {
+		// Already connected or already scheduled to connect.
+		return;
+	}
+
+	int timeToNextRetry;
+	if (_connectRetries >= connectRetryTimesSize) {
+		timeToNextRetry = connectRetryTimes[connectRetryTimesSize - 1];
+	} else {
+		timeToNextRetry = connectRetryTimes[_connectRetries];
+		_connectRetries++; // Increase the number of connection attemps
+	}
+
+	qDebug() << "Backing off for" << timeToNextRetry << "seconds for next retry";
+	_connectAlignedTimer->start(timeToNextRetry / 2, timeToNextRetry * 2);
+	if (_connectAlignedTimer->lastError() != QSystemAlignedTimer::NoError) {
+		// Hopefully a future version of QSystemAlignedTimer implements this fallback
+		// For now, we have to do it ourselves.
+		qDebug() << "Note: using plain QTimer for retry";
+		_connectTimer->start(timeToNextRetry * 1000);
+	}
+}
+
+void BluetoothWatch::unscheduleConnect()
+{
+	_connectAlignedTimer->stop();
+	_connectTimer->stop();
+}
+
+void BluetoothWatch::connectToWatch()
+{
+	delete _socket; //Delete socket from previous connect if any.
+	_socket = new QBluetoothSocket(QBluetoothSocket::RfcommSocket);
+
+	connect(_socket, SIGNAL(connected()), SLOT(handleSocketConnected()));
+	connect(_socket, SIGNAL(disconnected()), SLOT(handleSocketDisconnected()));
+	connect(_socket, SIGNAL(readyRead()), SLOT(handleSocketData()));
+	connect(_socket, SIGNAL(error(QBluetoothSocket::SocketError)),
+			SLOT(handleSocketError(QBluetoothSocket::SocketError)));
+	connect(_socket, SIGNAL(stateChanged(QBluetoothSocket::SocketState)),
+			SLOT(handleSocketState(QBluetoothSocket::SocketState)));
+
+	_socket->connectToService(_address, 1, QIODevice::ReadWrite | QIODevice::Unbuffered);
+}
+
+void BluetoothWatch::handleConnectTimer()
+{
+	connectToWatch();
+}
+
+void BluetoothWatch::handleLocalDevModeChanged(QBluetoothLocalDevice::HostMode state)
+{
+	qDebug() << "Local bluetooth device mode changed to" << state;
+	if (state == QBluetoothLocalDevice::HostPoweredOff) {
+		// Host bluetooth was powered down
+		// Assume the socket has been disconnected
+		handleSocketDisconnected();
+		// Cancel any pending connection attempts
+		unscheduleConnect();
+	} else {
+		// Host bluetooth might have been powered up
+		if (!_connected) {
+			scheduleConnect();
+		}
+	}
+}
+
+void BluetoothWatch::handleSocketConnected()
+{
+	if (!_connected) {
+		qDebug() << "connected";
+
+		_connected = true;
+		_connectRetries = 0;
+
+		setupBluetoothWatch();
+
+		emit connected();
+	}
+}
+
+void BluetoothWatch::handleSocketDisconnected()
+{
+	// Signal disconnection if necessary
+	if (_connected) {
+		qDebug() << "disconnected";
+
+		_connected = false;
+		desetupBluetoothWatch();
+
+		emit disconnected();
+	}
+
+	// Setup reconnection attempt if necessary
+	if (_localDev->hostMode() != QBluetoothLocalDevice::HostPoweredOff) {
+		scheduleRetryConnect();
+	}
+}
+
+void BluetoothWatch::handleSocketError(QBluetoothSocket::SocketError error)
+{
+	qWarning() << "Socket error:" << error;
+	// Seems that sometimes a disconnection event may not be generated.
+	handleSocketDisconnected();
+}
+
+void BluetoothWatch::handleSocketState(QBluetoothSocket::SocketState state)
+{
+	qDebug() << "socket is in" << state;
+}