trunk/src/qsamplerDevice.cpp

// qsamplerDevice.cpp
//
/****************************************************************************
   Copyright (C) 2004-2007, rncbc aka Rui Nuno Capela. All rights reserved.
   Copyright (C) 2007, Christian Schoenebeck

   This program 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 2
   of the License, or (at your option) any later version.

   This program 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 this program; if not, write to the Free Software Foundation, Inc.,
   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

*****************************************************************************/

#include "qsamplerAbout.h"
#include "qsamplerDevice.h"

#include "qsamplerMainForm.h"
#include "qsamplerDeviceForm.h"

#include <QCheckBox>
#include <QSpinBox>
#include <QLineEdit>


using namespace QSampler;

//-------------------------------------------------------------------------
// qsamplerDeviceParam - MIDI/Audio Device parameter structure.
//

// Constructors.
qsamplerDeviceParam::qsamplerDeviceParam ( lscp_param_info_t *pParamInfo,
        const char *pszValue )
{
        setParam(pParamInfo, pszValue);
}


// Default destructor.
qsamplerDeviceParam::~qsamplerDeviceParam (void)
{
}


// Initializer.
void qsamplerDeviceParam::setParam ( lscp_param_info_t *pParamInfo,
        const char *pszValue )
{
        if (pParamInfo == NULL)
                return;

        // Info structure field members.

        type = pParamInfo->type;

        if (pParamInfo->description)
                description = pParamInfo->description;
        else
                description = QString::null;

        mandatory = (bool) pParamInfo->mandatory;
        fix = (bool) pParamInfo->fix;
        multiplicity = (bool) pParamInfo->multiplicity;

        depends.clear();
        for (int i = 0; pParamInfo->depends && pParamInfo->depends[i]; i++)
                depends.append(pParamInfo->depends[i]);

        if (pParamInfo->defaultv)
                defaultv = pParamInfo->defaultv;
        else
                defaultv = QString::null;

        if (pParamInfo->range_min)
                range_min = pParamInfo->range_min;
        else
                range_min = QString::null;

        if (pParamInfo->range_max)
                range_max = pParamInfo->range_max;
        else
                range_max = QString::null;

        possibilities.clear();
        for (int i = 0; pParamInfo->possibilities && pParamInfo->possibilities[i]; i++)
                possibilities.append(pParamInfo->possibilities[i]);

        // The current parameter value.
        if (pszValue)
                value = pszValue;
        else
                value = QString::null;
}


//-------------------------------------------------------------------------
// qsamplerDevice - MIDI/Audio Device structure.
//

// Constructor.
qsamplerDevice::qsamplerDevice ( qsamplerDeviceType deviceType, int iDeviceID )
{
//      m_ports.setAutoDelete(true);

        setDevice(deviceType, iDeviceID);
}

// Default destructor.
qsamplerDevice::~qsamplerDevice (void)
{
        qDeleteAll(m_ports);
        m_ports.clear();
}

// Copy constructor.
qsamplerDevice::qsamplerDevice ( const qsamplerDevice& device )
        : m_params(device.m_params), m_ports(device.m_ports)
{
        m_iDeviceID   = device.m_iDeviceID;
        m_deviceType  = device.m_deviceType;
        m_sDeviceType = device.m_sDeviceType;
        m_sDriverName = device.m_sDriverName;
        m_sDeviceName = device.m_sDeviceName;
}


// Initializer.
void qsamplerDevice::setDevice ( qsamplerDeviceType deviceType, int iDeviceID )
{
        MainForm *pMainForm = MainForm::getInstance();
        if (pMainForm == NULL)
                return;
        if (pMainForm->client() == NULL)
                return;

        // Device id and type should be always set.
        m_iDeviceID  = iDeviceID;
        m_deviceType = deviceType;

        // Reset device parameters and ports anyway.
        m_params.clear();
        qDeleteAll(m_ports);
        m_ports.clear();

        // Retrieve device info, if any.
        lscp_device_info_t *pDeviceInfo = NULL;
        switch (deviceType) {
        case qsamplerDevice::Audio:
                m_sDeviceType = QObject::tr("Audio");
                if (m_iDeviceID >= 0 && (pDeviceInfo = ::lscp_get_audio_device_info(
                                pMainForm->client(), m_iDeviceID)) == NULL)
                        appendMessagesClient("lscp_get_audio_device_info");
                break;
        case qsamplerDevice::Midi:
                m_sDeviceType = QObject::tr("MIDI");
                if (m_iDeviceID >= 0 && (pDeviceInfo = ::lscp_get_midi_device_info(
                                pMainForm->client(), m_iDeviceID)) == NULL)
                        appendMessagesClient("lscp_get_midi_device_info");
                break;
        case qsamplerDevice::None:
                m_sDeviceType = QString::null;
                break;
        }
        // If we're bogus, bail out...
        if (pDeviceInfo == NULL) {
                m_sDriverName = QString::null;
                m_sDeviceName = QObject::tr("New %1 device").arg(m_sDeviceType);
                return;
        }

        // Other device properties...
        m_sDriverName = pDeviceInfo->driver;
        m_sDeviceName = m_sDriverName + ' '
                + QObject::tr("Device %1").arg(m_iDeviceID);

        // Grab device parameters...
        for (int i = 0; pDeviceInfo->params && pDeviceInfo->params[i].key; i++) {
                const QString sParam = pDeviceInfo->params[i].key;
                lscp_param_info_t *pParamInfo = NULL;
                switch (deviceType) {
                case qsamplerDevice::Audio:
                        if ((pParamInfo = ::lscp_get_audio_driver_param_info(
                                        pMainForm->client(), m_sDriverName.toUtf8().constData(),
                                        sParam.toUtf8().constData(), NULL)) == NULL)
                                appendMessagesClient("lscp_get_audio_driver_param_info");
                        break;
                case qsamplerDevice::Midi:
                        if ((pParamInfo = ::lscp_get_midi_driver_param_info(
                                        pMainForm->client(), m_sDriverName.toUtf8().constData(),
                                        sParam.toUtf8().constData(), NULL)) == NULL)
                                appendMessagesClient("lscp_get_midi_driver_param_info");
                        break;
                case qsamplerDevice::None:
                        break;
                }
                if (pParamInfo) {
                        m_params[sParam.toUpper()] = qsamplerDeviceParam(pParamInfo,
                                pDeviceInfo->params[i].value);
                }
        }

        // Refresh parameter dependencies...
        refreshParams();
        // Set port/channel list...
        refreshPorts();
}


// Driver name initializer/settler.
void qsamplerDevice::setDriver ( const QString& sDriverName )
{
        MainForm *pMainForm = MainForm::getInstance();
        if (pMainForm == NULL)
                return;
        if (pMainForm->client() == NULL)
                return;

        // Valid only for scratch devices.
        if (m_sDriverName == sDriverName)
                return;

        // Reset device parameters and ports anyway.
        m_params.clear();
        qDeleteAll(m_ports);
        m_ports.clear();

        // Retrieve driver info, if any.
        lscp_driver_info_t *pDriverInfo = NULL;
        switch (m_deviceType) {
        case qsamplerDevice::Audio:
                if ((pDriverInfo = ::lscp_get_audio_driver_info(pMainForm->client(),
                                sDriverName.toUtf8().constData())) == NULL)
                        appendMessagesClient("lscp_get_audio_driver_info");
                break;
        case qsamplerDevice::Midi:
                if ((pDriverInfo = ::lscp_get_midi_driver_info(pMainForm->client(),
                                sDriverName.toUtf8().constData())) == NULL)
                        appendMessagesClient("lscp_get_midi_driver_info");
                break;
        case qsamplerDevice::None:
                break;
        }

        // If we're bogus, bail out...
        if (pDriverInfo == NULL)
                return;

        // Remember device parameters...
        m_sDriverName = sDriverName;

        // Grab driver parameters...
        for (int i = 0; pDriverInfo->parameters && pDriverInfo->parameters[i]; i++) {
                const QString sParam = pDriverInfo->parameters[i];
                lscp_param_info_t *pParamInfo = NULL;
                switch (m_deviceType) {
                case qsamplerDevice::Audio:
                        if ((pParamInfo = ::lscp_get_audio_driver_param_info(
                                        pMainForm->client(), sDriverName.toUtf8().constData(),
                                        sParam.toUtf8().constData(), NULL)) == NULL)
                                appendMessagesClient("lscp_get_audio_driver_param_info");
                        break;
                case qsamplerDevice::Midi:
                        if ((pParamInfo = ::lscp_get_midi_driver_param_info(
                                        pMainForm->client(), sDriverName.toUtf8().constData(),
                                        sParam.toUtf8().constData(), NULL)) == NULL)
                                appendMessagesClient("lscp_get_midi_driver_param_info");
                        break;
                case qsamplerDevice::None:
                        break;
                }
                if (pParamInfo) {
                        m_params[sParam.toUpper()] = qsamplerDeviceParam(pParamInfo,
                                pParamInfo->defaultv);
                }
        }

        // Refresh parameter dependencies...
        refreshParams();
        // Set port/channel list...
        refreshPorts();
}


// Device property accessors.
int qsamplerDevice::deviceID (void) const
{
        return m_iDeviceID;
}

qsamplerDevice::qsamplerDeviceType qsamplerDevice::deviceType (void) const
{
        return m_deviceType;
}

const QString& qsamplerDevice::deviceTypeName (void) const
{
        return m_sDeviceType;
}

const QString& qsamplerDevice::driverName (void) const
{
        return m_sDriverName;
}

// Special device name formatter.
QString qsamplerDevice::deviceName (void) const
{
        QString sPrefix;
        if (m_iDeviceID >= 0)
            sPrefix += m_sDeviceType + ' ';
        return sPrefix + m_sDeviceName;
}


// Set the proper device parameter value.
bool qsamplerDevice::setParam ( const QString& sParam,
        const QString& sValue )
{
        MainForm *pMainForm = MainForm::getInstance();
        if (pMainForm == NULL)
                return false;
        if (pMainForm->client() == NULL)
                return false;

        // Set proper device parameter.
        m_params[sParam.toUpper()].value = sValue;

        // If the device already exists, things get immediate...
        int iRefresh = 0;
        if (m_iDeviceID >= 0 && sValue != QString::null) {

                // we need temporary byte arrrays with the final strings, because
                // i.e. QString::toUtf8() only returns a temporary object and the
                // C-style char* pointers for liblscp would immediately be invalidated
                QByteArray finalParamKey = sParam.toUtf8();
                QByteArray finalParamVal = sValue.toUtf8();

                // Prepare parameter struct.
                lscp_param_t param;
                param.key   = (char *) finalParamKey.constData();
                param.value = (char *) finalParamVal.constData();
                // Now it depends on the device type...
                lscp_status_t ret = LSCP_FAILED;
                switch (m_deviceType) {
                case qsamplerDevice::Audio:
                    if (sParam == "CHANNELS") iRefresh++;
                        if ((ret = ::lscp_set_audio_device_param(pMainForm->client(),
                                        m_iDeviceID, &param)) != LSCP_OK)
                                appendMessagesClient("lscp_set_audio_device_param");
                        break;
                case qsamplerDevice::Midi:
                    if (sParam == "PORTS") iRefresh++;
                        if ((ret = ::lscp_set_midi_device_param(pMainForm->client(),
                                        m_iDeviceID, &param)) != LSCP_OK)
                                appendMessagesClient("lscp_set_midi_device_param");
                        break;
                case qsamplerDevice::None:
                        break;
                }
                // Show result.
                if (ret == LSCP_OK) {
                        appendMessages(QString("%1: %2.").arg(sParam).arg(sValue));
                        // Special care for specific parameter changes...
                        if (iRefresh > 0)
                                iRefresh += refreshPorts();
                        iRefresh += refreshDepends(sParam);
                } else {
                        // Oops...
                        appendMessagesError(
                                QObject::tr("Could not set device parameter value.\n\nSorry."));
                }
        }

        // Return whether we're need a view refresh.
        return (iRefresh > 0);
}


// Device parameter accessor.
const qsamplerDeviceParamMap& qsamplerDevice::params (void) const
{
        return m_params;
}


// Device port/channel list accessor.
qsamplerDevicePortList& qsamplerDevice::ports (void)
{
        return m_ports;
}


// Create a new device, as a copy of this current one.
bool qsamplerDevice::createDevice (void)
{
        MainForm *pMainForm = MainForm::getInstance();
        if (pMainForm == NULL)
                return false;
        if (pMainForm->client() == NULL)
                return false;

        // we need temporary lists with the final strings, because i.e.
        // QString::toUtf8() only returns a temporary object and the
        // C-style char* pointers for liblscp would immediately be invalidated
        QList<QByteArray> finalKeys;
        QList<QByteArray> finalVals;

        qsamplerDeviceParamMap::ConstIterator iter;
        for (iter = m_params.begin(); iter != m_params.end(); ++iter) {
                if (iter.value().value == QString::null) continue;
                finalKeys.push_back(iter.key().toUtf8());
                finalVals.push_back(iter.value().value.toUtf8());
        }

        // yeah, we DO HAVE to do the two loops separately !

        // Build the parameter list...
        lscp_param_t *pParams = new lscp_param_t [finalKeys.count() + 1];
        int iParam;
        for (iParam = 0; iParam < finalKeys.count(); iParam++) {
                pParams[iParam].key   = (char *) finalKeys[iParam].constData();
                pParams[iParam].value = (char *) finalVals[iParam].constData();
        }
        // Null terminated.
        pParams[iParam].key   = NULL;
        pParams[iParam].value = NULL;

        // Now it depends on the device type...
        switch (m_deviceType) {
        case qsamplerDevice::Audio:
                if ((m_iDeviceID = ::lscp_create_audio_device(pMainForm->client(),
                                m_sDriverName.toUtf8().constData(), pParams)) < 0)
                        appendMessagesClient("lscp_create_audio_device");
                break;
        case qsamplerDevice::Midi:
                if ((m_iDeviceID = ::lscp_create_midi_device(pMainForm->client(),
                                m_sDriverName.toUtf8().constData(), pParams)) < 0)
                        appendMessagesClient("lscp_create_midi_device");
                break;
        case qsamplerDevice::None:
                break;
        }

        // Free used parameter array.
        delete pParams;

        // Show result.
        if (m_iDeviceID >= 0) {
                // Refresh our own stuff...
                setDevice(m_deviceType, m_iDeviceID);
                appendMessages(QObject::tr("created."));
        } else {
                appendMessagesError(QObject::tr("Could not create device.\n\nSorry."));
        }

        // Return whether we're a valid device...
        return (m_iDeviceID >= 0);
}


// Destroy existing device.
bool qsamplerDevice::deleteDevice (void)
{
        MainForm *pMainForm = MainForm::getInstance();
        if (pMainForm == NULL)
                return false;
        if (pMainForm->client() == NULL)
                return false;

        // Now it depends on the device type...
        lscp_status_t ret = LSCP_FAILED;
        switch (m_deviceType) {
        case qsamplerDevice::Audio:
                if ((ret = ::lscp_destroy_audio_device(pMainForm->client(),
                                m_iDeviceID)) != LSCP_OK)
                        appendMessagesClient("lscp_destroy_audio_device");
                break;
        case qsamplerDevice::Midi:
                if ((ret = ::lscp_destroy_midi_device(pMainForm->client(),
                                m_iDeviceID)) != LSCP_OK)
                        appendMessagesClient("lscp_destroy_midi_device");
                break;
        case qsamplerDevice::None:
                break;
        }

        // Show result.
        if (ret == LSCP_OK) {
                appendMessages(QObject::tr("deleted."));
                m_iDeviceID = -1;
        } else {
                appendMessagesError(QObject::tr("Could not delete device.\n\nSorry."));
        }

        // Return whether we've done it..
        return (ret == LSCP_OK);
}


// Device parameter dependencies refreshner.
int qsamplerDevice::refreshParams (void)
{
        // This should only make sense for scratch devices...
        if (m_iDeviceID >= 0)
            return 0;
        // Refresh all parameters that have dependencies...
        int iParams = 0;
        qsamplerDeviceParamMap::ConstIterator iter;
        for (iter = m_params.begin(); iter != m_params.end(); ++iter)
                iParams += refreshParam(iter.key());
        // Return how many parameters have been refreshed...
        return iParams;
}


// Device port/channel list refreshner.
int qsamplerDevice::refreshPorts (void)
{
        // This should only make sense for actual devices...
        if (m_iDeviceID < 0)
            return 0;
        // Port/channel count determination...
        int iPorts = 0;
        switch (m_deviceType) {
        case qsamplerDevice::Audio:
                iPorts = m_params["CHANNELS"].value.toInt();
                break;
        case qsamplerDevice::Midi:
                iPorts = m_params["PORTS"].value.toInt();
                break;
        case qsamplerDevice::None:
                break;
        }
        // Retrieve port/channel information...
        qDeleteAll(m_ports);
        m_ports.clear();
        for (int iPort = 0; iPort < iPorts; iPort++)
                m_ports.append(new qsamplerDevicePort(*this, iPort));
        // Return how many ports have been refreshed...
        return iPorts;
}


// Refresh/set dependencies given that some parameter has changed.
int qsamplerDevice::refreshDepends ( const QString& sParam )
{
        // This should only make sense for scratch devices...
        if (m_iDeviceID >= 0)
            return 0;
        // Refresh all parameters that depend on this one...
        int iDepends = 0;
        qsamplerDeviceParamMap::ConstIterator iter;
        for (iter = m_params.begin(); iter != m_params.end(); ++iter) {
                const QStringList& depends = iter.value().depends;
                if (depends.indexOf(sParam) >= 0)
                        iDepends += refreshParam(iter.key());
        }
        // Return how many dependencies have been refreshed...
        return iDepends;
}


// Refresh/set given parameter based on driver supplied dependencies.
int qsamplerDevice::refreshParam ( const QString& sParam )
{
        MainForm *pMainForm = MainForm::getInstance();
        if (pMainForm == NULL)
                return 0;
        if (pMainForm->client() == NULL)
                return 0;

        // Check if we have dependencies...
        qsamplerDeviceParam& param = m_params[sParam.toUpper()];
        if (param.depends.isEmpty())
                return 0;

        int iRefresh = 0;

        // Build dependency list...
        lscp_param_t *pDepends = new lscp_param_t [param.depends.count() + 1];
        int iDepend = 0;

        // we need temporary lists with the final strings, because i.e.
        // QString::toUtf8() only returns a temporary object and the
        // C-style char* pointers for liblscp would immediately be invalidated
        QList<QByteArray> finalKeys;
        QList<QByteArray> finalVals;
        for (int i = 0; i < param.depends.count(); i++) {
                const QString& sDepend = param.depends[i];
                finalKeys.push_back(sDepend.toUtf8());
                finalVals.push_back(m_params[sDepend.toUpper()].value.toUtf8());
        }
        // yeah, we DO HAVE to do those two loops separately !
        for (int i = 0; i < param.depends.count(); i++) {
                pDepends[iDepend].key   = (char *) finalKeys[i].constData();
                pDepends[iDepend].value = (char *) finalVals[i].constData();
                ++iDepend;
        }
        // Null terminated.
        pDepends[iDepend].key   = NULL;
        pDepends[iDepend].value = NULL;

        // FIXME: Some parameter dependencies (e.g.ALSA CARD)
        // are blocking for no reason, causing potential timeout-crashes.
        // hopefully this gets mitigated if this dependency hell is only
        // carried out for scratch devices...

        // Retrieve some modern parameters...
        lscp_param_info_t *pParamInfo = NULL;
        switch (m_deviceType) {
        case qsamplerDevice::Audio:
                if ((pParamInfo = ::lscp_get_audio_driver_param_info(
                                pMainForm->client(), m_sDriverName.toUtf8().constData(),
                                sParam.toUtf8().constData(), pDepends)) == NULL)
                        appendMessagesClient("lscp_get_audio_driver_param_info");
                break;
        case qsamplerDevice::Midi:
                if ((pParamInfo = ::lscp_get_midi_driver_param_info(
                                pMainForm->client(), m_sDriverName.toUtf8().constData(),
                                sParam.toUtf8().constData(), pDepends)) == NULL)
                        appendMessagesClient("lscp_get_midi_driver_param_info");
                break;
        case qsamplerDevice::None:
                break;
        }
        if (pParamInfo) {
                param = qsamplerDeviceParam(pParamInfo,
                        param.value.isEmpty() ? NULL : param.value.toUtf8().constData());
                iRefresh++;
        }

        // Free used parameter array.
        delete pDepends;

        // Return whether the parameters has been changed...
        return iRefresh;
}


// Redirected messages output methods.
void qsamplerDevice::appendMessages( const QString& s ) const
{
        MainForm *pMainForm = MainForm::getInstance();
        if (pMainForm)
                pMainForm->appendMessages(deviceName() + ' ' + s);
}

void qsamplerDevice::appendMessagesColor( const QString& s,
        const QString& c ) const
{
        MainForm *pMainForm = MainForm::getInstance();
        if (pMainForm)
                pMainForm->appendMessagesColor(deviceName() + ' ' + s, c);
}

void qsamplerDevice::appendMessagesText( const QString& s ) const
{
        MainForm *pMainForm = MainForm::getInstance();
        if (pMainForm)
                pMainForm->appendMessagesText(deviceName() + ' ' + s);
}

void qsamplerDevice::appendMessagesError( const QString& s ) const
{
        MainForm *pMainForm = MainForm::getInstance();
        if (pMainForm)
                pMainForm->appendMessagesError(deviceName() + "\n\n" + s);
}

void qsamplerDevice::appendMessagesClient( const QString& s ) const
{
        MainForm *pMainForm = MainForm::getInstance();
        if (pMainForm)
                pMainForm->appendMessagesClient(deviceName() + ' ' + s);
}


// Device ids enumerator.
int *qsamplerDevice::getDevices ( lscp_client_t *pClient,
        qsamplerDeviceType deviceType )
{
        int *piDeviceIDs = NULL;
        switch (deviceType) {
        case qsamplerDevice::Audio:
                piDeviceIDs = ::lscp_list_audio_devices(pClient);
                break;
        case qsamplerDevice::Midi:
                piDeviceIDs = ::lscp_list_midi_devices(pClient);
                break;
        case qsamplerDevice::None:
                break;
        }
        return piDeviceIDs;
}


// Driver names enumerator.
QStringList qsamplerDevice::getDrivers ( lscp_client_t *pClient,
        qsamplerDeviceType deviceType )
{
        QStringList drivers;

        const char **ppszDrivers = NULL;
        switch (deviceType) {
        case qsamplerDevice::Audio:
                ppszDrivers = ::lscp_list_available_audio_drivers(pClient);
                break;
        case qsamplerDevice::Midi:
                ppszDrivers = ::lscp_list_available_midi_drivers(pClient);
                break;
        case qsamplerDevice::None:
                break;
        }

        for (int iDriver = 0; ppszDrivers && ppszDrivers[iDriver]; iDriver++)
                drivers.append(ppszDrivers[iDriver]);

        return drivers;
}


//-------------------------------------------------------------------------
// qsamplerDevicePort - MIDI/Audio Device port/channel structure.
//

// Constructor.
qsamplerDevicePort::qsamplerDevicePort ( qsamplerDevice& device,
        int iPortID ) : m_device(device)
{
        setDevicePort(iPortID);
}

// Default destructor.
qsamplerDevicePort::~qsamplerDevicePort (void)
{
}


// Initializer.
void qsamplerDevicePort::setDevicePort ( int iPortID )
{
        MainForm *pMainForm = MainForm::getInstance();
        if (pMainForm == NULL)
                return;
        if (pMainForm->client() == NULL)
                return;

        // Device port id should be always set.
        m_iPortID = iPortID;

        // Reset port parameters anyway.
        m_params.clear();

        // Retrieve device port/channel info, if any.
        lscp_device_port_info_t *pPortInfo = NULL;
        switch (m_device.deviceType()) {
        case qsamplerDevice::Audio:
                if ((pPortInfo = ::lscp_get_audio_channel_info(pMainForm->client(),
                                m_device.deviceID(), m_iPortID)) == NULL)
                        m_device.appendMessagesClient("lscp_get_audio_channel_info");
                break;
        case qsamplerDevice::Midi:
                if ((pPortInfo = ::lscp_get_midi_port_info(pMainForm->client(),
                                m_device.deviceID(), m_iPortID)) == NULL)
                        m_device.appendMessagesClient("lscp_get_midi_port_info");
                break;
        case qsamplerDevice::None:
                break;
        }

        // If we're bogus, bail out...
        if (pPortInfo == NULL) {
                m_sPortName = QString::null;
                return;
        }

        // Set device port/channel properties...
        m_sPortName = pPortInfo->name;

        // Grab device port/channel parameters...
        m_params.clear();
        for (int i = 0; pPortInfo->params && pPortInfo->params[i].key; i++) {
                const QString sParam = pPortInfo->params[i].key;
                lscp_param_info_t *pParamInfo = NULL;
                switch (m_device.deviceType()) {
                case qsamplerDevice::Audio:
                        if ((pParamInfo = ::lscp_get_audio_channel_param_info(
                                        pMainForm->client(), m_device.deviceID(),
                                        m_iPortID, sParam.toUtf8().constData())) == NULL)
                                m_device.appendMessagesClient("lscp_get_audio_channel_param_info");
                        break;
                case qsamplerDevice::Midi:
                        if ((pParamInfo = ::lscp_get_midi_port_param_info(
                                        pMainForm->client(), m_device.deviceID(),
                                        m_iPortID, sParam.toUtf8().constData())) == NULL)
                                m_device.appendMessagesClient("lscp_get_midi_port_param_info");
                        break;
                case qsamplerDevice::None:
                        break;
                }
                if (pParamInfo) {
                        m_params[sParam.toUpper()] = qsamplerDeviceParam(pParamInfo,
                                pPortInfo->params[i].value);
                }
        }
}


// Device port/channel property accessors.
int qsamplerDevicePort::portID (void) const
{
        return m_iPortID;
}

const QString& qsamplerDevicePort::portName (void) const
{
        return m_sPortName;
}

// Device port/channel parameter accessor.
const qsamplerDeviceParamMap& qsamplerDevicePort::params (void) const
{
        return m_params;
}


// Set the proper device port/channel parameter value.
bool qsamplerDevicePort::setParam ( const QString& sParam,
        const QString& sValue )
{
        MainForm *pMainForm = MainForm::getInstance();
        if (pMainForm == NULL)
                return false;
        if (pMainForm->client() == NULL)
                return false;

        // Set proper port/channel parameter.
        m_params[sParam.toUpper()].value = sValue;

        // If the device already exists, things get immediate...
        int iRefresh = 0;
        if (m_device.deviceID() >= 0 && m_iPortID >= 0) {

                // we need temporary byte arrrays with the final strings, because
                // i.e. QString::toUtf8() only returns a temporary object and the
                // C-style char* pointers for liblscp would immediately be invalidated
                QByteArray finalParamKey = sParam.toUtf8();
                QByteArray finalParamVal = sValue.toUtf8();

                // Prepare parameter struct.
                lscp_param_t param;
                param.key   = (char *) finalParamKey.constData();
                param.value = (char *) finalParamVal.constData();
                // Now it depends on the device type...
                lscp_status_t ret = LSCP_FAILED;
                switch (m_device.deviceType()) {
                case qsamplerDevice::Audio:
                        if ((ret = ::lscp_set_audio_channel_param(pMainForm->client(),
                                        m_device.deviceID(), m_iPortID, &param)) != LSCP_OK)
                                m_device.appendMessagesClient("lscp_set_audio_channel_param");
                        break;
                case qsamplerDevice::Midi:
                        if ((ret = ::lscp_set_midi_port_param(pMainForm->client(),
                                        m_device.deviceID(), m_iPortID, &param)) != LSCP_OK)
                                m_device.appendMessagesClient("lscp_set_midi_port_param");
                        break;
                case qsamplerDevice::None:
                        break;
                }
                // Show result.
                if (ret == LSCP_OK) {
                        m_device.appendMessages(m_sPortName
                                + ' ' + QString("%1: %2.").arg(sParam).arg(sValue));
                        iRefresh++;
                } else {
                        m_device.appendMessagesError(
                                QObject::tr("Could not set %1 parameter value.\n\n"
                                        "Sorry.").arg(m_sPortName));
                }
        }

        // Return whether we're need a view refresh.
        return (iRefresh > 0);
}


//-------------------------------------------------------------------------
// qsamplerDeviceItem - QTreeWidget device item.
//

// Constructors.
qsamplerDeviceItem::qsamplerDeviceItem ( QTreeWidget* pTreeWidget,
        qsamplerDevice::qsamplerDeviceType deviceType )
        : QTreeWidgetItem(pTreeWidget, QSAMPLER_DEVICE_ITEM),
      m_device(deviceType)
{
        switch(m_device.deviceType()) {
        case qsamplerDevice::Audio:
                setIcon(0, QPixmap(":/icons/audio1.png"));
                setText(0, QObject::tr("Audio Devices"));
                break;
        case qsamplerDevice::Midi:
                setIcon(0, QPixmap(":/icons/midi1.png"));
                setText(0, QObject::tr("MIDI Devices"));
                break;
        case qsamplerDevice::None:
                break;
        }
}

qsamplerDeviceItem::qsamplerDeviceItem ( QTreeWidgetItem* pItem,
        qsamplerDevice::qsamplerDeviceType deviceType,
        int iDeviceID )
        : QTreeWidgetItem(pItem, QSAMPLER_DEVICE_ITEM),
      m_device(deviceType, iDeviceID)
{
        switch(m_device.deviceType()) {
        case qsamplerDevice::Audio:
                setIcon(0, QPixmap(":/icons/audio2.png"));
                break;
        case qsamplerDevice::Midi:
                setIcon(0, QPixmap(":/icons/midi2.png"));
                break;
        case qsamplerDevice::None:
                break;
        }

        setText(0, m_device.deviceName());
}

// Default destructor.
qsamplerDeviceItem::~qsamplerDeviceItem ()
{
}

// Instance accessors.
qsamplerDevice& qsamplerDeviceItem::device ()
{
        return m_device;
}


//-------------------------------------------------------------------------
// AbstractDeviceParamModel - data model base class for device parameters
//

AbstractDeviceParamModel::AbstractDeviceParamModel(QObject* parent) : QAbstractTableModel(parent), bEditable(false) {
    params = NULL;
}

int AbstractDeviceParamModel::rowCount(const QModelIndex& /*parent*/) const {
    //std::cout << "model size=" << params.size() << "\n" << std::flush;
    return (params) ? params->size() : 0;
}

int AbstractDeviceParamModel::columnCount(const QModelIndex& /*parent*/) const {
    return 3;
}

Qt::ItemFlags AbstractDeviceParamModel::flags(const QModelIndex& /*index*/) const {
    return Qt::ItemIsSelectable | Qt::ItemIsEditable | Qt::ItemIsEnabled;
}

QVariant AbstractDeviceParamModel::headerData(int section, Qt::Orientation orientation, int role) const {
    if (role != Qt::DisplayRole) return QVariant();

    if (orientation == Qt::Horizontal) {
        switch (section) {
            case 0:  return tr("Parameter");
            case 1:  return tr("Value");
            case 2:  return tr("Description");
            default: return QVariant();
        }
    }

    return QVariant();
}

void AbstractDeviceParamModel::refresh(const qsamplerDeviceParamMap* params, bool bEditable) {
    this->params    = params;
    this->bEditable = bEditable;
    // inform the outer world (QTableView) that our data changed
    QAbstractTableModel::reset();
}

void AbstractDeviceParamModel::clear() {
    params = NULL;
    // inform the outer world (QTableView) that our data changed
    QAbstractTableModel::reset();
}


//-------------------------------------------------------------------------
// DeviceParamModel - data model for device parameters (used for QTableView)
//

DeviceParamModel::DeviceParamModel(QObject* parent) : AbstractDeviceParamModel(parent) {
    device = NULL;
}

QVariant DeviceParamModel::data(const QModelIndex &index, int role) const {
    if (!index.isValid()) {
        //std::cout << "inavlid device model index\n" << std::flush;
        return QVariant();
    }
    if (role != Qt::DisplayRole) {
        //std::cout << "inavlid display role\n" << std::flush;
        return QVariant();
    }

    DeviceParameterRow item;
    item.name  = params->keys()[index.row()];
    item.param = (*params)[item.name];
    item.alive = device != NULL && device->deviceID() >= 0;

    return QVariant::fromValue(item);
}

bool DeviceParamModel::setData(const QModelIndex& index, const QVariant& value, int /*role*/) {
    if (!index.isValid()) {
        return false;
    }
    QString key = params->keys()[index.row()];
    //params[key].value = value.toString();
    device->setParam(key, value.toString());
    emit dataChanged(index, index);
    return true;
}

void DeviceParamModel::refresh(qsamplerDevice* pDevice, bool bEditable) {
    device = pDevice;
    AbstractDeviceParamModel::refresh(&pDevice->params(), bEditable);
}

void DeviceParamModel::clear() {
    AbstractDeviceParamModel::clear();
    device = NULL;
}


//-------------------------------------------------------------------------
// PortParamModel - data model for port parameters (used for QTableView)
//

PortParamModel::PortParamModel(QObject* parent) : AbstractDeviceParamModel(parent) {
    port = NULL;
}

QVariant PortParamModel::data(const QModelIndex &index, int role) const {
    if (!index.isValid()) {
        //std::cout << "inavlid device model index\n" << std::flush;
        return QVariant();
    }
    if (role != Qt::DisplayRole) {
        //std::cout << "inavlid display role\n" << std::flush;
        return QVariant();
    }

    DeviceParameterRow item;
    item.name  = params->keys()[index.row()];
    item.param = (*params)[item.name];
    item.alive = port != NULL && port->portID() >= 0;

    return QVariant::fromValue(item);
}

bool PortParamModel::setData(const QModelIndex& index, const QVariant& value, int /*role*/) {
    if (!index.isValid()) {
        return false;
    }
    QString key = params->keys()[index.row()];
    //params[key].value = value.toString();
    port->setParam(key, value.toString());
    emit dataChanged(index, index);
    return true;
}

void PortParamModel::refresh(qsamplerDevicePort* pPort, bool bEditable) {
    port = pPort;
    AbstractDeviceParamModel::refresh(&pPort->params(), bEditable);
}

void PortParamModel::clear() {
    AbstractDeviceParamModel::clear();
    port = NULL;
}


//-------------------------------------------------------------------------
// DeviceParamDelegate - table cell renderer for device/port parameters
//

DeviceParamDelegate::DeviceParamDelegate(QObject *parent) : QItemDelegate(parent) {
}

QWidget* DeviceParamDelegate::createEditor(QWidget *parent,
        const QStyleOptionViewItem &/* option */,
        const QModelIndex& index) const
{
    if (!index.isValid()) {
        return NULL;
    }

    DeviceParameterRow r = index.model()->data(index, Qt::DisplayRole).value<DeviceParameterRow>();

    const bool bEnabled = (r.alive) ? !r.param.fix : true;

    QString val = (r.alive) ? r.param.value : r.param.defaultv;

    switch (index.column()) {
        case 0:
            return new QLabel(r.name, parent);
        case 1: {
            if (r.param.type == LSCP_TYPE_BOOL) {
                QCheckBox* pCheckBox = new QCheckBox(parent);
                if (val != QString::null)
                    pCheckBox->setChecked(val.toLower() == "true");
                pCheckBox->setEnabled(bEnabled);
                return pCheckBox;
            } else if (r.param.possibilities.count() > 0) {
                QStringList opts = r.param.possibilities;
                if (r.param.multiplicity)
                    opts.prepend(tr("(none)"));
                QComboBox* pComboBox = new QComboBox(parent);
                pComboBox->addItems(opts);
                if (r.param.value.isEmpty())
                    pComboBox->setCurrentIndex(0);
                else
                    pComboBox->setCurrentIndex(pComboBox->findText(val));
                pComboBox->setEnabled(bEnabled);
                return pComboBox;
            } else if (r.param.type == LSCP_TYPE_INT && bEnabled) {
                QSpinBox* pSpinBox = new QSpinBox(parent);
                pSpinBox->setMinimum(
                    (!r.param.range_min.isEmpty()) ?
                        r.param.range_min.toInt() : 0 // or better a negative default min value ?
                );
                pSpinBox->setMaximum(
                    (!r.param.range_max.isEmpty()) ?
                        r.param.range_max.toInt() : (1 << 16) // or better a nigher default max value ?
                );
                pSpinBox->setValue(val.toInt());
                return pSpinBox;
            } else if (bEnabled) {
                QLineEdit* pLineEdit = new QLineEdit(val, parent);
                return pLineEdit;
            } else {
                QLabel* pLabel = new QLabel(val, parent);
                return pLabel;
            }
        }
        case 2:
            return new QLabel(r.param.description, parent);
        default:
            return NULL;
    }
}

void DeviceParamDelegate::setEditorData(QWidget* /*editor*/, const QModelIndex& /*index*/) const {
    // unused, since we set the editor data already in createEditor()
}

void DeviceParamDelegate::setModelData(QWidget* editor, QAbstractItemModel* model, const QModelIndex& index) const {
    if (index.column() == 1) {
        DeviceParameterRow r = index.model()->data(index, Qt::DisplayRole).value<DeviceParameterRow>();
        if (editor->metaObject()->className() == "QCheckBox") {
            QCheckBox* pCheckBox = static_cast<QCheckBox*>(editor);
            model->setData(index, QVariant(pCheckBox->checkState() == Qt::Checked));
        } else if (editor->metaObject()->className() == "QComboBox") {
            QComboBox* pComboBox = static_cast<QComboBox*>(editor);
            model->setData(index, pComboBox->currentText());
        } else if (editor->metaObject()->className() == "QSpinBox") {
            QSpinBox* pSpinBox = static_cast<QSpinBox*>(editor);
            model->setData(index, pSpinBox->value());
        } else if (editor->metaObject()->className() == "QLineEdit") {
            QLineEdit* pLineEdit = static_cast<QLineEdit*>(editor);
            model->setData(index, pLineEdit->text());
        } else if (editor->metaObject()->className() == "QLabel") {
            QLabel* pLabel = static_cast<QLabel*>(editor);
            model->setData(index, pLabel->text());
        }
    }
}

void DeviceParamDelegate::updateEditorGeometry(QWidget* editor,
        const QStyleOptionViewItem &option, const QModelIndex &/* index */) const
{
    if (editor) editor->setGeometry(option.rect);
}

// end of qsamplerDevice.cpp