qohosnativegestureshandler.cpp

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// Copyright (C) 2025 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 "qohosnativegestureshandler.h"
#include <QtCore/private/qohoslogger_p.h>
#include <private/qhighdpiscaling_p.h>
#include <qohosinputmethodeventhandler.h>
#include <qohosjsmain.h>
#include <qohosplatformintegration.h>
#include <qohosutils.h>
#include <render/qohosbatchingrequestshandler.h>
#include <utility>
#include <vector>
 
QT_BEGIN_NAMESPACE
 
namespace {
 
constexpr auto gestureEventMinAgeForDrop = std::chrono::milliseconds(20);
 
class QOhosNativeGesturesHandler final : public QEnableSharedFromThis<QOhosNativeGesturesHandler>
{
public:
    QOhosNativeGesturesHandler(
        QtOhos::QThreadSafeRef<QWindow> qWindowRef,
        std::function<void(QOhosNativeGestureEvent &)> qtThreadEventTransformer);
 
    void processGestureEventInJsThread(const QOhosNativeGestureEvent &event);
 
private:
    void processGestureEventsInQtThread(std::vector<QOhosNativeGestureEvent> &&batch);
 
    QtOhos::QThreadSafeRef<QWindow> m_qWindowRef;
    std::function<void(QOhosNativeGestureEvent &)> m_qtThreadEventTransformer;
    QOhosConsumer<QOhosNativeGestureEvent> m_gestureEventsHandler;
};
 
QOhosNativeGesturesHandler::QOhosNativeGesturesHandler(
    QtOhos::QThreadSafeRef<QWindow> qWindowRef,
    std::function<void(QOhosNativeGestureEvent &)> qtThreadEventTransformer)
    : m_qWindowRef(qWindowRef)
    , m_qtThreadEventTransformer(std::move(qtThreadEventTransformer))
{
}
 
void QOhosNativeGesturesHandler::processGestureEventInJsThread(
    const QOhosNativeGestureEvent &event)
{
    if (!m_gestureEventsHandler) {
        auto weakSelf = sharedFromThis().toWeakRef();
        m_gestureEventsHandler = makeQtOhosSimpleBatchingQtRequestsHandler<QOhosNativeGestureEvent>(
            m_qWindowRef.toQObjectThreadSafeRef(),
            [weakSelf](std::vector<QOhosNativeGestureEvent> &&batch) {
                auto sharedSelf = weakSelf.toStrongRef();
                if (!sharedSelf.isNull())
                    sharedSelf->processGestureEventsInQtThread(std::move(batch));
            });
    }
 
    m_gestureEventsHandler(event);
}
 
void QOhosNativeGesturesHandler::processGestureEventsInQtThread(std::vector<QOhosNativeGestureEvent> &&batch)
{
    auto *inputMethodEventHandler =
        QOhosPlatformIntegration::instance()->inputMethodEventHandler();
 
    if (inputMethodEventHandler == nullptr) {
        qOhosPrintfError("Cannot dispatch gesture event: inputMethodEventHandler is nullptr.");
        return;
    }
 
    const auto now = std::chrono::steady_clock::now();
 
    const auto mayDropGestureEvent = [now](const auto &event, const auto &nextEvent) {
        return now - event.timestamp >= gestureEventMinAgeForDrop
            && event.gestureType == nextEvent.gestureType
            && event.deviceType == nextEvent.deviceType;
    };
 
    batch.erase(
        QtOhos::removeMatchingWithLookahead(
            batch.begin(), batch.end(), mayDropGestureEvent),
        batch.end());
 
    const auto *platformScreen = m_qWindowRef.data()->screen()->handle();
 
    for (auto &event : batch) {
        m_qtThreadEventTransformer(event);
 
        auto screenBasedPosition = QHighDpi::fromNativePixels(
            event.displayBasedPosition, platformScreen);
        inputMethodEventHandler->onGestureEventFromNativeNode(
            m_qWindowRef.data(), event.gestureTimestamp, event.value, event.localPosition,
            screenBasedPosition, event.gestureType, event.deviceType);
    }
}
 
}
 
QOhosConsumer<const QOhosNativeGestureEvent &> makeQOhosNativeGesturesHandler(
    QtOhos::QThreadSafeRef<QWindow> qWindowRef,
    std::function<void(QOhosNativeGestureEvent &)> optQtThreadEventTransformer)
{
    auto gesturesHandler = QSharedPointer<QOhosNativeGesturesHandler>::create(
        qWindowRef,
        optQtThreadEventTransformer
            ? std::move(optQtThreadEventTransformer)
            : [](QOhosNativeGestureEvent &) {
            });
    return [gesturesHandler](const QOhosNativeGestureEvent &event) {
        gesturesHandler->processGestureEventInJsThread(event);
    };
}
 
QT_END_NAMESPACE