qwasmmediadevices.cpp

Go to the documentation of this file.

// Copyright (C) 2021 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qwasmmediadevices_p.h"
#include "private/qcameradevice_p.h"
 
#include "qwasmaudiosource_p.h"
#include "qwasmaudiosink_p.h"
#include "qwasmaudiodevice_p.h"
#include <AL/al.h>
#include <AL/alc.h>
 
#include <QMap>
#include <QDebug>
 
QT_BEGIN_NAMESPACE
 
Q_LOGGING_CATEGORY(qWasmMediaDevices, "qt.multimedia.wasm.mediadevices")
 
QWasmCameraDevices::QWasmCameraDevices(QPlatformMediaIntegration *integration)
    : QPlatformVideoDevices(integration)
{
    m_mediaDevices = QPlatformMediaDevices::instance();
}
 
QList<QCameraDevice> QWasmCameraDevices::videoDevices() const
{
    QWasmMediaDevices *wasmMediaDevices = reinterpret_cast<QWasmMediaDevices *>(m_mediaDevices);
    return wasmMediaDevices ? wasmMediaDevices->videoInputs() : QList<QCameraDevice>();
}
 
QWasmMediaDevices::QWasmMediaDevices()
{
    initDevices();
}
 
void QWasmMediaDevices::initDevices()
{
    if (m_initDone)
        return;
 
    m_initDone = true;
    getOpenALAudioDevices();
    getMediaDevices(); // asynchronous
}
 
QList<QAudioDevice> QWasmMediaDevices::audioInputs() const
{
    return m_audioInputs.values();
}
 
QList<QAudioDevice> QWasmMediaDevices::audioOutputs() const
{
    return m_audioOutputs.values();
}
 
QList<QCameraDevice> QWasmMediaDevices::videoInputs() const
{
    return m_cameraDevices.values();
}
 
QPlatformAudioSource *QWasmMediaDevices::createAudioSource(const QAudioDevice &deviceInfo,
                                                           QObject *parent)
{
    return new QWasmAudioSource(deviceInfo.id(), parent);
}
 
QPlatformAudioSink *QWasmMediaDevices::createAudioSink(const QAudioDevice &deviceInfo,
                                                       QObject *parent)
{
    return new QWasmAudioSink(deviceInfo.id(), parent);
}
 
void QWasmMediaDevices::getMediaDevices()
{
    emscripten::val navigator = emscripten::val::global("navigator");
    m_jsMediaDevicesInterface = navigator["mediaDevices"];
 
    if (m_jsMediaDevicesInterface.isNull() || m_jsMediaDevicesInterface.isUndefined()) {
        qWarning() << "No media devices found";
        return;
    }
 
    qstdweb::PromiseCallbacks enumerateDevicesCallback{
        .thenFunc =
                [&](emscripten::val devices) {
                    if (devices.isNull() || devices.isUndefined()) {
                        qWarning() << "Something went wrong enumerating devices";
                        return;
                    }
 
                    QList<std::string> cameraDevicesToRemove = m_cameraDevices.keys();
                    QList<std::string> audioInputsToRemove = m_audioInputs.keys();
                    QList<std::string> audioOutputsToRemove = m_audioOutputs.keys();
 
                    m_videoInputsAdded = false;
                    m_audioInputsAdded = false;
                    m_audioOutputsAdded = false;
 
                    bool m_videoInputsRemoved = false;
                    bool m_audioInputsRemoved = false;
                    bool m_audioOutputsRemoved = false;
 
                    for (int i = 0; i < devices["length"].as<int>(); i++) {
 
                        emscripten::val mediaDevice = devices[i];
 
                        std::string defaultDeviceLabel = "";
 
                        const std::string deviceKind = mediaDevice["kind"].as<std::string>();
                        const std::string label = mediaDevice["label"].as<std::string>();
                        const std::string deviceId = mediaDevice["deviceId"].as<std::string>();
 
                        qCDebug(qWasmMediaDevices) << QString::fromStdString(deviceKind)
                                                   << QString::fromStdString(deviceId)
                                                   << QString::fromStdString(label);
 
                        if (deviceKind.empty())
                            continue;
 
                        if (deviceId == std::string("default")) {
                            // chrome specifies the default device with this as deviceId
                            // and then prepends "Default - " with the name of the device
                            // in the label
                            if (label.empty())
                                continue;
 
                            defaultDeviceLabel = label;
                            continue;
                        }
 
                        const bool isDefault =
                                (defaultDeviceLabel.find(label) != std::string::npos);
 
                        if (deviceKind == std::string("videoinput")) {
                            if (!m_cameraDevices.contains(deviceId)) {
                                QCameraDevicePrivate *camera = new QCameraDevicePrivate; // QSharedData
                                camera->id = QString::fromStdString(deviceId).toUtf8();
                                camera->description = QString::fromUtf8(label.c_str());
                                camera->isDefault = isDefault;
 
                                m_cameraDevices.insert(deviceId, camera->create());
                                m_videoInputsAdded = true;
                            }
                            cameraDevicesToRemove.removeOne(deviceId);
 
                        } else if (deviceKind == std::string("audioinput")) {
                            if (!m_audioInputs.contains(deviceId)) {
                                m_audioInputs.insert(deviceId,
                                        (new QWasmAudioDevice(deviceId.c_str(), label.c_str(),
                                                              isDefault, QAudioDevice::Input))
                                                ->create());
 
                                m_audioInputsAdded = true;
                            }
                            audioInputsToRemove.removeOne(deviceId);
                        } else if (deviceKind == std::string("audiooutput")) {
                            if (!m_audioOutputs.contains(deviceId)) {
                                m_audioOutputs.insert(deviceId,
                                        (new QWasmAudioDevice(deviceId.c_str(), label.c_str(),
                                                              isDefault, QAudioDevice::Input))
                                                ->create());
 
                                m_audioOutputsAdded = true;
                            }
                            audioOutputsToRemove.removeOne(deviceId);
                        }
                        // if permissions are given label will hold the actual
                        // camera name, such as "Live! Cam Sync 1080p (041e:409d)"
                    }
 
                    // any left here were removed
                    int j = 0;
                    for (; j < cameraDevicesToRemove.count(); j++) {
                        m_cameraDevices.remove(cameraDevicesToRemove.at(j));
                    }
                    m_videoInputsRemoved = !cameraDevicesToRemove.isEmpty();
 
                    for (j = 0; j < audioInputsToRemove.count(); j++) {
                        m_audioInputs.remove(audioInputsToRemove.at(j));
                    }
                    m_audioInputsRemoved = !audioInputsToRemove.isEmpty();
 
                    for (j = 0; j < audioOutputsToRemove.count(); j++) {
                        m_audioOutputs.remove(audioOutputsToRemove.at(j));
                    }
                    m_audioOutputsRemoved = !audioOutputsToRemove.isEmpty();
 
                    if (m_videoInputsAdded || m_videoInputsRemoved)
                        emit videoInputsChanged();
                    if (m_audioInputsAdded || m_audioInputsRemoved)
                        emit audioInputsChanged();
                    if (m_audioOutputsAdded || m_audioOutputsRemoved)
                        emit audioOutputsChanged();
 
                },
        .catchFunc =
                [this](emscripten::val error) {
                    qWarning() << "mediadevices enumerateDevices fail"
                               << QString::fromStdString(error["name"].as<std::string>())
                               << QString::fromStdString(error["message"].as<std::string>());
                    m_initDone = false;
                }
    };
 
    qstdweb::Promise::make(m_jsMediaDevicesInterface,
                           QStringLiteral("enumerateDevices"),
                           std::move(enumerateDevicesCallback));
 
    // setup devicechange monitor
    m_deviceChangedCallback = std::make_unique<qstdweb::EventCallback>(
            m_jsMediaDevicesInterface, "devicechange",
            [this, enumerateDevicesCallback](emscripten::val) {
                qstdweb::Promise::make(m_jsMediaDevicesInterface,
                                       QStringLiteral("enumerateDevices"),
                                       std::move(enumerateDevicesCallback));
            });
}
 
void QWasmMediaDevices::getOpenALAudioDevices()
{
    // VM3959:4 The AudioContext was not allowed to start.
    // It must be resumed (or created) after a user gesture on the page. https://goo.gl/7K7WLu
    auto capture = alcGetString(nullptr, ALC_CAPTURE_DEFAULT_DEVICE_SPECIFIER);
    // present even if there is no capture device
    if (capture && !m_audioOutputs.contains(capture)) {
        m_audioInputs.insert(capture,
                             (new QWasmAudioDevice(capture, "WebAssembly audio capture device",
                                                   true, QAudioDevice::Input))
                                     ->create());
        emit audioInputsChanged();
    }
 
    auto playback = alcGetString(nullptr, ALC_DEFAULT_DEVICE_SPECIFIER);
    // present even if there is no playback device
    if (playback && !m_audioOutputs.contains(capture)) {
        m_audioOutputs.insert(playback,
                              (new QWasmAudioDevice(playback, "WebAssembly audio playback device",
                                                    true, QAudioDevice::Output))
                                      ->create());
        emit audioOutputsChanged();
    }
}
 
QT_END_NAMESPACE