/****************************************************************************
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** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
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** This file is part of the Qt Toolkit.
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** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
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** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
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****************************************************************************/

#include <QDebug>
#include <QFile>

#include "dsvideodevicecontrol.h"
#include "dscamerasession.h"

#include <tchar.h>
#include <dshow.h>
#include <objbase.h>
#include <initguid.h>
#include <ocidl.h>
#include <string.h>

extern const CLSID CLSID_VideoInputDeviceCategory;

QT_BEGIN_NAMESPACE

DSVideoDeviceControl::DSVideoDeviceControl(QObject *parent)
    : QVideoDeviceSelectorControl(parent)
{
    m_session = qobject_cast<DSCameraSession*>(parent);

    enumerateDevices(&m_devices, &m_descriptions);

    selected = 0;
}

int DSVideoDeviceControl::deviceCount() const
{
    return m_devices.count();
}

QString DSVideoDeviceControl::deviceName(int index) const
{
    if (index >= 0 && index <= m_devices.count())
        return QString::fromUtf8(m_devices.at(index).constData());

    return QString();
}

QString DSVideoDeviceControl::deviceDescription(int index) const
{
    if (index >= 0 && index <= m_descriptions.count())
        return m_descriptions.at(index);

    return QString();
}

int DSVideoDeviceControl::defaultDevice() const
{
    return 0;
}

int DSVideoDeviceControl::selectedDevice() const
{
    return selected;
}

void DSVideoDeviceControl::enumerateDevices(QList<QByteArray> *devices, QStringList *descriptions)
{
    devices->clear();
    descriptions->clear();

    CoInitialize(NULL);
    ICreateDevEnum* pDevEnum = NULL;
    IEnumMoniker* pEnum = NULL;
    // Create the System device enumerator
    HRESULT hr = CoCreateInstance(CLSID_SystemDeviceEnum, NULL,
            CLSCTX_INPROC_SERVER, IID_ICreateDevEnum,
            reinterpret_cast<void**>(&pDevEnum));
    if (SUCCEEDED(hr)) {
        // Create the enumerator for the video capture category
        hr = pDevEnum->CreateClassEnumerator(
                CLSID_VideoInputDeviceCategory, &pEnum, 0);
        if (S_OK == hr) {
            pEnum->Reset();
            // go through and find all video capture devices
            IMoniker* pMoniker = NULL;
            IMalloc *mallocInterface = 0;
            CoGetMalloc(1, (LPMALLOC*)&mallocInterface);
            while (pEnum->Next(1, &pMoniker, NULL) == S_OK) {
                BSTR strName = 0;
                hr = pMoniker->GetDisplayName(NULL, NULL, &strName);
                if (SUCCEEDED(hr)) {
                    QString output(QString::fromWCharArray(strName));
                    mallocInterface->Free(strName);
                    devices->append(output.toUtf8().constData());

                    IPropertyBag *pPropBag;
                    hr = pMoniker->BindToStorage(0, 0, IID_IPropertyBag, (void**)(&pPropBag));
                    if (SUCCEEDED(hr)) {
                        // Find the description
                        VARIANT varName;
                        varName.vt = VT_BSTR;
                        hr = pPropBag->Read(L"FriendlyName", &varName, 0);
                        if (SUCCEEDED(hr)) {
                            output = QString::fromWCharArray(varName.bstrVal);
                        }
                        pPropBag->Release();
                    }
                    descriptions->append(output);
                }
                pMoniker->Release();
            }
            mallocInterface->Release();
            pEnum->Release();
        }
        pDevEnum->Release();
    }
    CoUninitialize();
}

void DSVideoDeviceControl::setSelectedDevice(int index)
{
    if (index >= 0 && index <= m_devices.count()) {
        if (m_session) {
            QString device = m_devices.at(index);
            if (device.startsWith("ds:"))
                device.remove(0,3);
            m_session->setDevice(device);
        }
        selected = index;
    }
}

QT_END_NAMESPACE
