/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtBluetooth module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
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** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
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** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
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** included in the packaging of this file. Please review the following
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****************************************************************************/

#include "qbluetoothdevicediscoveryagent.h"
#include "osx/osxbtledeviceinquiry_p.h"
#include "osx/osxbtdeviceinquiry_p.h"
#include "qbluetoothlocaldevice.h"
#include "osx/osxbtsdpinquiry_p.h"
#include "qbluetoothdeviceinfo.h"
#include "osx/osxbtnotifier_p.h"
#include "osx/osxbtutility_p.h"
#include "osx/osxbluetooth_p.h"
#include "osx/uistrings_p.h"
#include "qbluetoothhostinfo.h"
#include "qbluetoothaddress.h"
#include "osx/uistrings_p.h"
#include "qbluetoothuuid.h"

#include <QtCore/qloggingcategory.h>
#include <QtCore/qscopedpointer.h>
#include <QtCore/qglobal.h>
#include <QtCore/qstring.h>
#include <QtCore/qdebug.h>
#include <QtCore/qlist.h>

#include <Foundation/Foundation.h>

QT_BEGIN_NAMESPACE

namespace
{

void registerQDeviceDiscoveryMetaType()
{
    static bool initDone = false;
    if (!initDone) {
        qRegisterMetaType<QBluetoothDeviceInfo>();
        qRegisterMetaType<QBluetoothDeviceDiscoveryAgent::Error>();
        initDone = true;
    }
}

}//namespace

class QBluetoothDeviceDiscoveryAgentPrivate : public QObject,
                                              public OSXBluetooth::DeviceInquiryDelegate
{
    friend class QBluetoothDeviceDiscoveryAgent;
public:
    template<class T>
    using ObjCScopedPointer = OSXBluetooth::ObjCScopedPointer<T>;
    using LEDeviceInquiryObjC = QT_MANGLE_NAMESPACE(OSXBTLEDeviceInquiry);

    QBluetoothDeviceDiscoveryAgentPrivate(const QBluetoothAddress & address,
                                          QBluetoothDeviceDiscoveryAgent *q);

    ~QBluetoothDeviceDiscoveryAgentPrivate() override;

    bool isValid() const;
    bool isActive() const;

    void start(QBluetoothDeviceDiscoveryAgent::DiscoveryMethods methods);
    void startClassic();
    void startLE();
    void stop();

private:
    enum AgentState {
        NonActive,
        ClassicScan,
        LEScan
    };

    // DeviceInquiryDelegate:
    void inquiryFinished(IOBluetoothDeviceInquiry *inq) override;
    void error(IOBluetoothDeviceInquiry *inq, IOReturn error) override;
    void deviceFound(IOBluetoothDeviceInquiry *inq, IOBluetoothDevice *device) override;

    void LEinquiryFinished();
    void LEinquiryError(QBluetoothDeviceDiscoveryAgent::Error error);
    void LEnotSupported();

    // Check if it's a really new device/updated info and emit
    // q_ptr->deviceDiscovered.
    void deviceFound(const QBluetoothDeviceInfo &newDeviceInfo);

    void setError(IOReturn error, const QString &text = QString());
    void setError(QBluetoothDeviceDiscoveryAgent::Error,
                  const QString &text = QString());

    QBluetoothDeviceDiscoveryAgent *q_ptr;
    AgentState agentState;

    QBluetoothAddress adapterAddress;

    bool startPending;
    bool stopPending;

    QBluetoothDeviceDiscoveryAgent::Error lastError;
    QString errorString;

    QBluetoothDeviceDiscoveryAgent::InquiryType inquiryType;

    using DeviceInquiry = ObjCScopedPointer<DeviceInquiryObjC>;
    DeviceInquiry inquiry;

    using LEDeviceInquiry = ObjCScopedPointer<LEDeviceInquiryObjC>;
    LEDeviceInquiry inquiryLE;

    using HostController = ObjCScopedPointer<IOBluetoothHostController>;
    HostController hostController;

    using DevicesList = QList<QBluetoothDeviceInfo>;
    DevicesList discoveredDevices;

    int lowEnergySearchTimeout;
    QBluetoothDeviceDiscoveryAgent::DiscoveryMethods requestedMethods;
};

QBluetoothDeviceDiscoveryAgentPrivate::QBluetoothDeviceDiscoveryAgentPrivate(const QBluetoothAddress &adapter,
                                                                             QBluetoothDeviceDiscoveryAgent *q) :
    q_ptr(q),
    agentState(NonActive),
    adapterAddress(adapter),
    startPending(false),
    stopPending(false),
    lastError(QBluetoothDeviceDiscoveryAgent::NoError),
    inquiryType(QBluetoothDeviceDiscoveryAgent::GeneralUnlimitedInquiry),
    lowEnergySearchTimeout(OSXBluetooth::defaultLEScanTimeoutMS),
    requestedMethods(QBluetoothDeviceDiscoveryAgent::ClassicMethod
                     | QBluetoothDeviceDiscoveryAgent::LowEnergyMethod)
{
    registerQDeviceDiscoveryMetaType();

    Q_ASSERT_X(q != nullptr, Q_FUNC_INFO, "invalid q_ptr (null)");

    HostController controller([[IOBluetoothHostController defaultController] retain]);
    if (!controller || [controller powerState] != kBluetoothHCIPowerStateON) {
        qCCritical(QT_BT_OSX) << "no default host controller or adapter is off";
        return;
    }

    hostController.reset(controller.take());
}

QBluetoothDeviceDiscoveryAgentPrivate::~QBluetoothDeviceDiscoveryAgentPrivate()
{
    if (inquiryLE.data() && agentState != NonActive) {
        // We want the LE scan to stop as soon as possible.
        if (dispatch_queue_t leQueue = OSXBluetooth::qt_LE_queue()) {
            // Local variable to be retained ...
            LEDeviceInquiryObjC *inq = inquiryLE.data();
            dispatch_sync(leQueue, ^{
                [inq stop];
            });
        }
    }
}

bool QBluetoothDeviceDiscoveryAgentPrivate::isValid() const
{
    return hostController.data() && [hostController powerState] == kBluetoothHCIPowerStateON;
}

bool QBluetoothDeviceDiscoveryAgentPrivate::isActive() const
{
    if (startPending)
        return true;

    if (stopPending)
        return false;

    return agentState != NonActive;
}

void QBluetoothDeviceDiscoveryAgentPrivate::start(QBluetoothDeviceDiscoveryAgent::DiscoveryMethods methods)
{
    Q_ASSERT(isValid());
    Q_ASSERT(!isActive());
    Q_ASSERT(lastError != QBluetoothDeviceDiscoveryAgent::InvalidBluetoothAdapterError);
    Q_ASSERT(methods & (QBluetoothDeviceDiscoveryAgent::ClassicMethod
                        | QBluetoothDeviceDiscoveryAgent::LowEnergyMethod));

    requestedMethods = methods;

    if (stopPending) {
        startPending = true;
        return;
    }

    // This function (re)starts the scan(s) from the scratch;
    // starting from Classic if it's in 'methods' (or LE scan if not).

    agentState = NonActive;
    discoveredDevices.clear();
    setError(QBluetoothDeviceDiscoveryAgent::NoError);

    if (requestedMethods & QBluetoothDeviceDiscoveryAgent::ClassicMethod)
        return startClassic();

    startLE();
}

void QBluetoothDeviceDiscoveryAgentPrivate::startClassic()
{
    Q_ASSERT(isValid());
    Q_ASSERT(!isActive());
    Q_ASSERT(lastError == QBluetoothDeviceDiscoveryAgent::NoError);
    Q_ASSERT(requestedMethods & QBluetoothDeviceDiscoveryAgent::ClassicMethod);
    Q_ASSERT(agentState == NonActive);

    OSXBluetooth::qt_test_iobluetooth_runloop();

    if (!inquiry) {
        // The first Classic scan for this DDA.
        inquiry.reset([[DeviceInquiryObjC alloc]initWithDelegate:this]);
        if (!inquiry) {
            qCCritical(QT_BT_OSX) << "failed to initialize an Classic device inquiry";
            setError(QBluetoothDeviceDiscoveryAgent::UnknownError,
                     QCoreApplication::translate(DEV_DISCOVERY, DD_NOT_STARTED));
            emit q_ptr->error(lastError);
            return;
        }
    }

    agentState = ClassicScan;

    const IOReturn res = [inquiry start];
    if (res != kIOReturnSuccess) {
        setError(res, QCoreApplication::translate(DEV_DISCOVERY, DD_NOT_STARTED));
        agentState = NonActive;
        emit q_ptr->error(lastError);
    }
}

void QBluetoothDeviceDiscoveryAgentPrivate::startLE()
{
    Q_ASSERT(isValid());
    Q_ASSERT(lastError != QBluetoothDeviceDiscoveryAgent::InvalidBluetoothAdapterError);
    Q_ASSERT(requestedMethods & QBluetoothDeviceDiscoveryAgent::LowEnergyMethod);

    using namespace OSXBluetooth;

    QScopedPointer<LECBManagerNotifier> notifier(new LECBManagerNotifier);
    // Connections:
    using ErrMemFunPtr = void (LECBManagerNotifier::*)(QBluetoothDeviceDiscoveryAgent::Error);
    notifier->connect(notifier.data(), ErrMemFunPtr(&LECBManagerNotifier::CBManagerError),
                      this, &QBluetoothDeviceDiscoveryAgentPrivate::LEinquiryError);
    notifier->connect(notifier.data(), &LECBManagerNotifier::LEnotSupported,
                      this, &QBluetoothDeviceDiscoveryAgentPrivate::LEnotSupported);
    notifier->connect(notifier.data(), &LECBManagerNotifier::discoveryFinished,
                      this, &QBluetoothDeviceDiscoveryAgentPrivate::LEinquiryFinished);
    using DeviceMemFunPtr = void (QBluetoothDeviceDiscoveryAgentPrivate::*)(const QBluetoothDeviceInfo &);
    notifier->connect(notifier.data(), &LECBManagerNotifier::deviceDiscovered,
                      this, DeviceMemFunPtr(&QBluetoothDeviceDiscoveryAgentPrivate::deviceFound));

    // Check queue and create scanner:
    inquiryLE.reset([[LEDeviceInquiryObjC alloc] initWithNotifier:notifier.data()]);
    if (inquiryLE.data())
        notifier.take(); // Whatever happens next, inquiryLE is already the owner ...

    dispatch_queue_t leQueue(qt_LE_queue());
    if (!leQueue || !inquiryLE) {
        setError(QBluetoothDeviceDiscoveryAgent::UnknownError,
                 QCoreApplication::translate(DEV_DISCOVERY, DD_NOT_STARTED_LE));
        agentState = NonActive;
        emit q_ptr->error(lastError);
        return;
    }

    // Now start in on LE queue:
    agentState = LEScan;
    // We need the local variable so that it's retained ...
    LEDeviceInquiryObjC *inq = inquiryLE.data();
    dispatch_async(leQueue, ^{
        [inq startWithTimeout:lowEnergySearchTimeout];
    });
}

void QBluetoothDeviceDiscoveryAgentPrivate::stop()
{
    Q_ASSERT_X(isValid(), Q_FUNC_INFO, "called on invalid device discovery agent");
    Q_ASSERT_X(isActive(), Q_FUNC_INFO, "called whithout active inquiry");
    Q_ASSERT_X(lastError != QBluetoothDeviceDiscoveryAgent::InvalidBluetoothAdapterError,
               Q_FUNC_INFO, "called with invalid bluetooth adapter");

    using namespace OSXBluetooth;

    const bool prevStart = startPending;
    startPending = false;
    stopPending = true;

    setError(QBluetoothDeviceDiscoveryAgent::NoError);

    if (agentState == ClassicScan) {
        const IOReturn res = [inquiry stop];
        if (res != kIOReturnSuccess) {
            qCWarning(QT_BT_OSX) << "failed to stop";
            startPending = prevStart;
            stopPending = false;
            setError(res, QCoreApplication::translate(DEV_DISCOVERY, DD_NOT_STOPPED));
            emit q_ptr->error(lastError);
        }
    } else {
        dispatch_queue_t leQueue(qt_LE_queue());
        Q_ASSERT(leQueue);
        // We need the local variable so that it's retained ...
        LEDeviceInquiryObjC *inq = inquiryLE.data();
        dispatch_sync(leQueue, ^{
            [inq stop];
        });
        // We consider LE scan to be stopped immediately and
        // do not care about this LEDeviceInquiry object anymore.
        LEinquiryFinished();
    }
}

void QBluetoothDeviceDiscoveryAgentPrivate::inquiryFinished(IOBluetoothDeviceInquiry *inq)
{
    Q_UNUSED(inq)

    Q_ASSERT_X(isValid(), Q_FUNC_INFO, "invalid device discovery agent"); //We can never be here.

    // The subsequent start(LE) function (if any)
    // will (re)set the correct state.
    agentState = NonActive;

    if (stopPending && !startPending) {
        stopPending = false;
        emit q_ptr->canceled();
    } else if (startPending) {
        startPending = false;
        stopPending = false;
        start(requestedMethods);
    } else {
        // We can be here _only_ if a classic scan
        // finished in a normal way (not cancelled)
        // and requestedMethods includes LowEnergyMethod.
        // startLE() will take care of old devices
        // not supporting Bluetooth 4.0.
        if (requestedMethods & QBluetoothDeviceDiscoveryAgent::LowEnergyMethod)
            startLE();
        else
            emit q_ptr->finished();
    }
}

void QBluetoothDeviceDiscoveryAgentPrivate::error(IOBluetoothDeviceInquiry *inq, IOReturn error)
{
    Q_UNUSED(inq)

    Q_ASSERT_X(isValid(), Q_FUNC_INFO, "invalid device discovery agent");

    startPending = false;
    stopPending = false;

    setError(error);

    emit q_ptr->error(lastError);
}

void QBluetoothDeviceDiscoveryAgentPrivate::deviceFound(IOBluetoothDeviceInquiry *inq, IOBluetoothDevice *device)
{
    Q_UNUSED(inq)

    Q_ASSERT_X(isValid(), Q_FUNC_INFO, "invalid device discovery agent");
    Q_ASSERT_X(device, Q_FUNC_INFO, "invalid IOBluetoothDevice (nil)");
    Q_ASSERT_X(agentState == ClassicScan, Q_FUNC_INFO,
               "invalid agent state (expected classic scan)");

    QT_BT_MAC_AUTORELEASEPOOL;

    // Let's collect some info about this device:
    const QBluetoothAddress deviceAddress(OSXBluetooth::qt_address([device getAddress]));
    if (deviceAddress.isNull()) {
        qCWarning(QT_BT_OSX) << "invalid Bluetooth address";
        return;
    }

    QString deviceName;
    if (device.name)
        deviceName = QString::fromNSString(device.name);

    const qint32 classOfDevice(device.classOfDevice);

    QBluetoothDeviceInfo deviceInfo(deviceAddress, deviceName, classOfDevice);
    deviceInfo.setCoreConfigurations(QBluetoothDeviceInfo::BaseRateCoreConfiguration);
    deviceInfo.setRssi(device.RSSI);

    const QVector<QBluetoothUuid> uuids(OSXBluetooth::extract_services_uuids(device));
    deviceInfo.setServiceUuids(uuids);

    deviceFound(deviceInfo);
}

void QBluetoothDeviceDiscoveryAgentPrivate::setError(IOReturn error, const QString &text)
{
    if (error == kIOReturnSuccess)
        setError(QBluetoothDeviceDiscoveryAgent::NoError, text);
    else if (error == kIOReturnNoPower)
        setError(QBluetoothDeviceDiscoveryAgent::PoweredOffError, text);
    else
        setError(QBluetoothDeviceDiscoveryAgent::UnknownError, text);
}

void QBluetoothDeviceDiscoveryAgentPrivate::setError(QBluetoothDeviceDiscoveryAgent::Error error, const QString &text)
{
    lastError = error;

    if (text.length() > 0) {
        errorString = text;
    } else {
        switch (lastError) {
        case QBluetoothDeviceDiscoveryAgent::NoError:
            errorString = QString();
            break;
        case QBluetoothDeviceDiscoveryAgent::PoweredOffError:
            errorString = QCoreApplication::translate(DEV_DISCOVERY, DD_POWERED_OFF);
            break;
        case QBluetoothDeviceDiscoveryAgent::InvalidBluetoothAdapterError:
            errorString = QCoreApplication::translate(DEV_DISCOVERY, DD_INVALID_ADAPTER);
            break;
        case QBluetoothDeviceDiscoveryAgent::InputOutputError:
            errorString = QCoreApplication::translate(DEV_DISCOVERY, DD_IO);
            break;
        case QBluetoothDeviceDiscoveryAgent::UnknownError:
        default:
            errorString = QCoreApplication::translate(DEV_DISCOVERY, DD_UNKNOWN_ERROR);
        }
    }

    if (lastError != QBluetoothDeviceDiscoveryAgent::NoError)
        qCDebug(QT_BT_OSX) << "error set:"<<errorString;
}

void QBluetoothDeviceDiscoveryAgentPrivate::LEinquiryError(QBluetoothDeviceDiscoveryAgent::Error error)
{
    Q_ASSERT(error == QBluetoothDeviceDiscoveryAgent::PoweredOffError
             || error == QBluetoothDeviceDiscoveryAgent::UnsupportedDiscoveryMethod);

    inquiryLE.reset();

    startPending = false;
    stopPending = false;
    agentState = NonActive;
    setError(error);
    emit q_ptr->error(lastError);
}

void QBluetoothDeviceDiscoveryAgentPrivate::LEnotSupported()
{
    qCDebug(QT_BT_OSX) << "no Bluetooth LE support";

    if (requestedMethods & QBluetoothDeviceDiscoveryAgent::ClassicMethod) {
        // Having both Classic | LE means this is not an error.
        LEinquiryFinished();
    } else {
        // In the past this was never an error, that's why we have
        // LEnotSupported as a special method. But now, since
        // we can have separate Classic/LE scans, we have to report it
        // as UnsupportedDiscoveryMethod.
        LEinquiryError(QBluetoothDeviceDiscoveryAgent::UnsupportedDiscoveryMethod);
    }
}

void QBluetoothDeviceDiscoveryAgentPrivate::LEinquiryFinished()
{
    // The same logic as in inquiryFinished, but does not start LE scan.
    agentState = NonActive;
    inquiryLE.reset();

    if (stopPending && !startPending) {
        stopPending = false;
        emit q_ptr->canceled();
    } else if (startPending) {
        startPending = false;
        stopPending = false;
        start(requestedMethods); //Start again.
    } else {
        emit q_ptr->finished();
    }
}

void QBluetoothDeviceDiscoveryAgentPrivate::deviceFound(const QBluetoothDeviceInfo &newDeviceInfo)
{
    // Core Bluetooth does not allow us to access addresses, we have to use uuid instead.
    // This uuid has nothing to do with uuids in Bluetooth in general (it's generated by
    // Apple's framework using some algorithm), but it's a 128-bit uuid after all.
    const bool isLE = newDeviceInfo.coreConfigurations() == QBluetoothDeviceInfo::LowEnergyCoreConfiguration;

    for (int i = 0, e = discoveredDevices.size(); i < e; ++i) {
        if (isLE) {
            if (discoveredDevices[i].deviceUuid() == newDeviceInfo.deviceUuid()) {
                QBluetoothDeviceInfo::Fields updatedFields = QBluetoothDeviceInfo::Field::None;
                if (discoveredDevices[i].rssi() != newDeviceInfo.rssi()) {
                    qCDebug(QT_BT_OSX) << "Updating RSSI for" << newDeviceInfo.address()
                                       << newDeviceInfo.rssi();
                    discoveredDevices[i].setRssi(newDeviceInfo.rssi());
                    updatedFields.setFlag(QBluetoothDeviceInfo::Field::RSSI);
                }

                if (discoveredDevices[i].manufacturerData() != newDeviceInfo.manufacturerData()) {
                    qCDebug(QT_BT_OSX) << "Updating manufacturer data for" << newDeviceInfo.address();
                    const QVector<quint16> keys = newDeviceInfo.manufacturerIds();
                    for (auto key: keys)
                        discoveredDevices[i].setManufacturerData(key, newDeviceInfo.manufacturerData(key));
                    updatedFields.setFlag(QBluetoothDeviceInfo::Field::ManufacturerData);
                }

                if (lowEnergySearchTimeout > 0) {
                    if (discoveredDevices[i] != newDeviceInfo) {
                        discoveredDevices.replace(i, newDeviceInfo);
                        emit q_ptr->deviceDiscovered(newDeviceInfo);
                    } else {
                        if (!updatedFields.testFlag(QBluetoothDeviceInfo::Field::None))
                            emit q_ptr->deviceUpdated(discoveredDevices[i], updatedFields);
                    }

                    return;
                }

                discoveredDevices.replace(i, newDeviceInfo);
                emit q_ptr->deviceDiscovered(newDeviceInfo);

                if (!updatedFields.testFlag(QBluetoothDeviceInfo::Field::None))
                    emit q_ptr->deviceUpdated(discoveredDevices[i], updatedFields);

                return;
            }
        } else {
            if (discoveredDevices[i].address() == newDeviceInfo.address()) {
                if (discoveredDevices[i] == newDeviceInfo)
                    return;

                discoveredDevices.replace(i, newDeviceInfo);
                emit q_ptr->deviceDiscovered(newDeviceInfo);
                return;
            }
        }
    }

    discoveredDevices.append(newDeviceInfo);
    emit q_ptr->deviceDiscovered(newDeviceInfo);
}

QBluetoothDeviceDiscoveryAgent::QBluetoothDeviceDiscoveryAgent(QObject *parent) :
    QObject(parent),
    d_ptr(new QBluetoothDeviceDiscoveryAgentPrivate(QBluetoothAddress(), this))
{
}

QBluetoothDeviceDiscoveryAgent::QBluetoothDeviceDiscoveryAgent(
    const QBluetoothAddress &deviceAdapter, QObject *parent) :
    QObject(parent),
    d_ptr(new QBluetoothDeviceDiscoveryAgentPrivate(deviceAdapter, this))
{
    if (!deviceAdapter.isNull()) {
        const QList<QBluetoothHostInfo> localDevices = QBluetoothLocalDevice::allDevices();
        for (const QBluetoothHostInfo &hostInfo : localDevices) {
            if (hostInfo.address() == deviceAdapter)
                return;
        }
        d_ptr->setError(InvalidBluetoothAdapterError);
    }
}

QBluetoothDeviceDiscoveryAgent::~QBluetoothDeviceDiscoveryAgent()
{
    delete d_ptr;
}

QBluetoothDeviceDiscoveryAgent::InquiryType QBluetoothDeviceDiscoveryAgent::inquiryType() const
{
    return d_ptr->inquiryType;
}

void QBluetoothDeviceDiscoveryAgent::setInquiryType(InquiryType type)
{
    d_ptr->inquiryType = type;
}

QList<QBluetoothDeviceInfo> QBluetoothDeviceDiscoveryAgent::discoveredDevices() const
{
    return d_ptr->discoveredDevices;
}

QBluetoothDeviceDiscoveryAgent::DiscoveryMethods QBluetoothDeviceDiscoveryAgent::supportedDiscoveryMethods()
{
    return ClassicMethod | LowEnergyMethod;
}

void QBluetoothDeviceDiscoveryAgent::start()
{
    start(supportedDiscoveryMethods());
}

void QBluetoothDeviceDiscoveryAgent::start(DiscoveryMethods methods)
{
    if (methods == NoMethod)
        return;

    if ((supportedDiscoveryMethods() & methods) != methods) {
        d_ptr->lastError = UnsupportedDiscoveryMethod;
        d_ptr->errorString = tr("One or more device discovery methods "
                                "are not supported on this platform");
        emit error(d_ptr->lastError);
        return;
    }

    if (d_ptr->lastError != InvalidBluetoothAdapterError) {
        if (d_ptr->isValid()) {
            if (!isActive())
                d_ptr->start(methods);
        } else {
            // We previously failed to initialize d_ptr correctly:
            // either some memory allocation problem or
            // no BT adapter found.
            d_ptr->setError(InvalidBluetoothAdapterError);
            emit error(InvalidBluetoothAdapterError);
        }
    }
}

void QBluetoothDeviceDiscoveryAgent::stop()
{
    if (d_ptr->isValid()) {
        if (isActive() && d_ptr->lastError != InvalidBluetoothAdapterError)
            d_ptr->stop();
    }
}

bool QBluetoothDeviceDiscoveryAgent::isActive() const
{
    if (d_ptr->isValid())
        return d_ptr->isActive();

    return false;
}

QBluetoothDeviceDiscoveryAgent::Error QBluetoothDeviceDiscoveryAgent::error() const
{
    return d_ptr->lastError;
}

QString QBluetoothDeviceDiscoveryAgent::errorString() const
{
    return d_ptr->errorString;
}

void QBluetoothDeviceDiscoveryAgent::setLowEnergyDiscoveryTimeout(int timeout)
{
    // cannot deliberately turn it off
    if (timeout < 0) {
        qCDebug(QT_BT_OSX) << "The Bluetooth Low Energy device discovery timeout cannot be negative.";
        return;
    }

    d_ptr->lowEnergySearchTimeout = timeout;
    return;
}

int QBluetoothDeviceDiscoveryAgent::lowEnergyDiscoveryTimeout() const
{
    return d_ptr->lowEnergySearchTimeout;
}

QT_END_NAMESPACE
