JUCE/modules/juce_audio_plugin_client/utility/juce_FakeMouseMoveGenerator.h

/*
  ==============================================================================

   This file is part of the JUCE 6 technical preview.
   Copyright (c) 2020 - Raw Material Software Limited

   You may use this code under the terms of the GPL v3
   (see www.gnu.org/licenses).

   For this technical preview, this file is not subject to commercial licensing.

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/

namespace juce
{

#ifndef DOXYGEN

#if JUCE_MAC

//==============================================================================
// Helper class to workaround windows not getting mouse-moves...
class FakeMouseMoveGenerator  : private Timer
{
public:
    FakeMouseMoveGenerator()
    {
        startTimer (1000 / 30);
    }

    static bool componentContainsAudioProcessorEditor (Component* comp) noexcept
    {
        if (dynamic_cast<AudioProcessorEditor*> (comp) != nullptr)
            return true;

        for (auto* child : comp->getChildren())
            if (componentContainsAudioProcessorEditor (child))
                return true;

        return false;
    }

    void timerCallback() override
    {
        // Workaround for windows not getting mouse-moves...
        auto screenPos = Desktop::getInstance().getMainMouseSource().getScreenPosition();

        if (screenPos != lastScreenPos)
        {
            lastScreenPos = screenPos;
            auto mods = ModifierKeys::currentModifiers;

            if (! mods.isAnyMouseButtonDown())
            {
                if (auto* comp = Desktop::getInstance().findComponentAt (screenPos.roundToInt()))
                {
                    if (componentContainsAudioProcessorEditor (comp->getTopLevelComponent()))
                    {
                        safeOldComponent = comp;

                        if (auto* peer = comp->getPeer())
                        {
                            if (! peer->isFocused())
                            {
                                peer->handleMouseEvent (MouseInputSource::InputSourceType::mouse, peer->globalToLocal (screenPos), mods,
                                                        MouseInputSource::invalidPressure, MouseInputSource::invalidOrientation, Time::currentTimeMillis());
                            }
                        }

                        return;
                    }
                }

                if (safeOldComponent != nullptr)
                {
                    if (auto* peer = safeOldComponent->getPeer())
                    {
                        peer->handleMouseEvent (MouseInputSource::InputSourceType::mouse, MouseInputSource::offscreenMousePos, mods,
                                                MouseInputSource::invalidPressure, MouseInputSource::invalidOrientation, Time::currentTimeMillis());
                    }
                }

                safeOldComponent = nullptr;
            }
        }
    }

private:
    Point<float> lastScreenPos;
    WeakReference<Component> safeOldComponent;
};

#else
struct FakeMouseMoveGenerator {};
#endif

#endif

} // namespace juce