Add QBluetoothDeviceDiscoveryAgent::deviceUpdated signal

For iBeacons and such, it's normal to keep discovering indefinitely,
while the advertisement can sometimes carry changing payload data.
This signal helps keep the UI up-to-date.

Changed setManufacturerData to return a bool indicating whether the
data was really modified or not, to avoid sending deviceUpdated
in case it was not changed.

For convenience QBluetoothDeviceInfo::manufacturerData() was added.

WinRT and Apple platforms do not emit the new signal yet and relevant
TODO items were added.

Done-with: Shawn Rutledge <shawn.rutledge@qt.io>
Task-number: QTBUG-46008
Task-number: QTBUG-69747
Change-Id: I6d6b373f6cc5ee3dd6af2ad05d8640dbd25c5d6a
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>
Reviewed-by: Alex Blasche <alexander.blasche@qt.io>

6 files changed, 93 insertions, 10 deletions

diff --git a/src/bluetooth/qbluetoothdevicediscoveryagent.cpp b/src/bluetooth/qbluetoothdevicediscoveryagent.cpp
index a9e35960..ac978349 100644
--- a/src/bluetooth/qbluetoothdevicediscoveryagent.cpp
+++ b/src/bluetooth/qbluetoothdevicediscoveryagent.cpp
@@ -155,6 +155,26 @@ Q_DECLARE_LOGGING_CATEGORY(QT_BT)
 */
 
 /*!
+    \fn void QBluetoothDeviceDiscoveryAgent::deviceUpdated(const QBluetoothDeviceInfo &info, QBluetoothDeviceInfo::Fields updatedFields)
+
+    This signal is emitted when the agent receives additional information about
+    the Bluetooth device described by \a info. The \l updatedFields flags tell
+    which information has been updated.
+
+    During discovery, some information can change dynamically, such as
+    \l {signal strength}{QBluetoothDeviceInfo::rssi()} and
+    \l {manufacturerData}{QBluetoothDeviceInfo::manufacturerData()}.
+    This signal informs you that if your application is displaying this data, it
+    can be updated, rather than waiting until the discovery has finished.
+
+    \note This signal is only emitted on Android and BlueZ 5.x.
+
+    \sa QBluetoothDeviceInfo::rssi(), lowEnergyDiscoveryTimeout()
+*/
+
+// TODO deviceUpdated() signal not implemented on WinRT and Apple platforms
+
+/*!
     \fn void QBluetoothDeviceDiscoveryAgent::finished()
 
     This signal is emitted when Bluetooth device discovery completes.
diff --git a/src/bluetooth/qbluetoothdevicediscoveryagent.h b/src/bluetooth/qbluetoothdevicediscoveryagent.h
index d3e41265..f24478bf 100644
--- a/src/bluetooth/qbluetoothdevicediscoveryagent.h
+++ b/src/bluetooth/qbluetoothdevicediscoveryagent.h
@@ -112,6 +112,7 @@ public Q_SLOTS:
 
 Q_SIGNALS:
     void deviceDiscovered(const QBluetoothDeviceInfo &info);
+    void deviceUpdated(const QBluetoothDeviceInfo &info, QBluetoothDeviceInfo::Fields updatedFields);
     void finished();
     void error(QBluetoothDeviceDiscoveryAgent::Error error);
     void canceled();
diff --git a/src/bluetooth/qbluetoothdevicediscoveryagent_android.cpp b/src/bluetooth/qbluetoothdevicediscoveryagent_android.cpp
index c7afd578..50f3aef9 100644
--- a/src/bluetooth/qbluetoothdevicediscoveryagent_android.cpp
+++ b/src/bluetooth/qbluetoothdevicediscoveryagent_android.cpp
@@ -317,12 +317,29 @@ void QBluetoothDeviceDiscoveryAgentPrivate::processDiscoveredDevices(
 
     for (int i = 0; i < discoveredDevices.size(); i++) {
         if (discoveredDevices[i].address() == info.address()) {
-            if (discoveredDevices[i] == info && lowEnergySearchTimeout > 0) {
-                qCDebug(QT_BT_ANDROID) << "Duplicate: " << info.address()
-                                       << "isLeScanResult:" << isLeResult;
+            QBluetoothDeviceInfo::Fields updatedFields = QBluetoothDeviceInfo::Field::None;
+            if (discoveredDevices[i].rssi() != info.rssi()) {
+                qCDebug(QT_BT_ANDROID) << "Updating RSSI for" << info.address()
+                                       << info.rssi();
+                discoveredDevices[i].setRssi(info.rssi());
+                updatedFields.setFlag(QBluetoothDeviceInfo::Field::RSSI);
+            }
+            if (discoveredDevices[i].manufacturerData() != info.manufacturerData()) {
+                qCDebug(QT_BT_ANDROID) << "Updating manufacturer data for" << info.address();
+                const QVector<quint16> keys = info.manufacturerIds();
+                for (auto key: keys)
+                    discoveredDevices[i].setManufacturerData(key, info.manufacturerData(key));
+                updatedFields.setFlag(QBluetoothDeviceInfo::Field::ManufacturerData);
+            }
+
+            if (!updatedFields.testFlag(QBluetoothDeviceInfo::Field::None)) {
+                emit q->deviceUpdated(discoveredDevices[i], updatedFields);
                 return;
             }
 
+            if (discoveredDevices[i] == info)
+                return;
+
             if (discoveredDevices.at(i).name() == info.name()) {
                 qCDebug(QT_BT_ANDROID) << "Almost Duplicate "<< info.address()
                                        << info.name() << "- replacing in place";
diff --git a/src/bluetooth/qbluetoothdevicediscoveryagent_bluez.cpp b/src/bluetooth/qbluetoothdevicediscoveryagent_bluez.cpp
index a5fdb323..a039c916 100644
--- a/src/bluetooth/qbluetoothdevicediscoveryagent_bluez.cpp
+++ b/src/bluetooth/qbluetoothdevicediscoveryagent_bluez.cpp
@@ -633,23 +633,27 @@ void QBluetoothDeviceDiscoveryAgentPrivate::_q_PropertiesChanged(const QString &
                                             QDBusConnection::systemBus());
         for (int i = 0; i < discoveredDevices.size(); i++) {
             if (discoveredDevices[i].address().toString() == device.address()) {
+                QBluetoothDeviceInfo::Fields updatedFields = QBluetoothDeviceInfo::Field::None;
                 if (changed_properties.contains(QStringLiteral("RSSI"))) {
                     qCDebug(QT_BT_BLUEZ) << "Updating RSSI for" << device.address()
                                          << changed_properties.value(QStringLiteral("RSSI"));
                     discoveredDevices[i].setRssi(
                                 changed_properties.value(QStringLiteral("RSSI")).toInt());
+                    updatedFields.setFlag(QBluetoothDeviceInfo::Field::RSSI);
                 }
                 if (changed_properties.contains(QStringLiteral("ManufacturerData"))) {
                     qCDebug(QT_BT_BLUEZ) << "Updating ManufacturerData for" << device.address();
-
-                    QVector<QPair<quint16,QByteArray>> manufacturerData;
                     ManufacturerDataList changedManufacturerData =
-                            qvariant_cast< ManufacturerDataList >(changed_properties.value(QStringLiteral("ManufacturerData")));
+                            qdbus_cast< ManufacturerDataList >(changed_properties.value(QStringLiteral("ManufacturerData")));
 
                     const QList<quint16> keys = changedManufacturerData.keys();
-                    for (quint16 key : keys)
-                        discoveredDevices[i].setManufacturerData(key, changedManufacturerData.value(key).variant().toByteArray());
+                    for (quint16 key : keys) {
+                        if (discoveredDevices[i].setManufacturerData(key, changedManufacturerData.value(key).variant().toByteArray()))
+                            updatedFields.setFlag(QBluetoothDeviceInfo::Field::ManufacturerData);
+                    }
                 }
+                if (!updatedFields.testFlag(QBluetoothDeviceInfo::Field::None))
+                    emit q->deviceUpdated(discoveredDevices[i], updatedFields);
                 return;
             }
         }
diff --git a/src/bluetooth/qbluetoothdeviceinfo.cpp b/src/bluetooth/qbluetoothdeviceinfo.cpp
index 11a60565..bd3b9c00 100644
--- a/src/bluetooth/qbluetoothdeviceinfo.cpp
+++ b/src/bluetooth/qbluetoothdeviceinfo.cpp
@@ -72,6 +72,20 @@ QT_BEGIN_NAMESPACE
 */
 
 /*!
+    \enum QBluetoothDeviceInfo::Field
+
+    This enum is used in conjuntion with the \l deviceUpdated() signal and indicates the field
+    that changed.
+
+    \value None             None of the values changed.
+    \value RSSI             The \l rssi() value of the device changed.
+    \value ManufacturerData The \l manufacturerData() field changed
+    \value All              Matches every possible field.
+
+    \since 5.12
+*/
+
+/*!
     \enum QBluetoothDeviceInfo::MinorMiscellaneousClass
 
     This enum describes the minor device classes for miscellaneous Bluetooth devices.
@@ -598,20 +612,38 @@ QVector<quint16> QBluetoothDeviceInfo::manufacturerIds() const
  */
 QByteArray QBluetoothDeviceInfo::manufacturerData(quint16 manufacturerId) const
 {
+    // TODO Currently not implemented on WinRT
     Q_D(const QBluetoothDeviceInfo);
     return d->manufacturerData.value(manufacturerId);
 }
 
 /*!
     Sets the advertised manufacturer \a data for the given \a manufacturerId.
+    Returns true if it was inserted or changed, false if it was already known.
 
     \sa manufacturerData,
     \since 5.12
 */
-void QBluetoothDeviceInfo::setManufacturerData(quint16 manufacturerId, const QByteArray &data)
+bool QBluetoothDeviceInfo::setManufacturerData(quint16 manufacturerId, const QByteArray &data)
 {
     Q_D(QBluetoothDeviceInfo);
+    const auto it = d->manufacturerData.find(manufacturerId);
+    if (it != d->manufacturerData.end() && *it == data)
+        return false;
     d->manufacturerData.insert(manufacturerId, data);
+    return true;
+}
+
+/*!
+    Returns the complete set of all manufacturer data.
+
+    \sa setManufacturerData
+    \since 5.12
+*/
+QHash<quint16, QByteArray> QBluetoothDeviceInfo::manufacturerData() const
+{
+    Q_D(const QBluetoothDeviceInfo);
+    return d->manufacturerData;
 }
 
 /*!
diff --git a/src/bluetooth/qbluetoothdeviceinfo.h b/src/bluetooth/qbluetoothdeviceinfo.h
index 88b477d8..d59eb27d 100644
--- a/src/bluetooth/qbluetoothdeviceinfo.h
+++ b/src/bluetooth/qbluetoothdeviceinfo.h
@@ -198,6 +198,14 @@ public:
         DataUnavailable
     };
 
+    enum class Field {
+        None = 0x0000,
+        RSSI = 0x0001,
+        ManufacturerData = 0x0002,
+        All = 0x7fff
+    };
+    Q_DECLARE_FLAGS(Fields, Field)
+
     enum CoreConfiguration {
         UnknownCoreConfiguration = 0x0,
         LowEnergyCoreConfiguration = 0x01,
@@ -239,7 +247,8 @@ public:
 
     QVector<quint16> manufacturerIds() const;
     QByteArray manufacturerData(quint16 manufacturerId) const;
-    void setManufacturerData(quint16 manufacturerId, const QByteArray &data);
+    bool setManufacturerData(quint16 manufacturerId, const QByteArray &data);
+    QHash<quint16, QByteArray> manufacturerData() const;
 
     void setCoreConfigurations(QBluetoothDeviceInfo::CoreConfigurations coreConfigs);
     QBluetoothDeviceInfo::CoreConfigurations coreConfigurations() const;