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/*
SPDX-FileCopyrightText: 2023 Fushan Wen <qydwhotmail@gmail.com>
SPDX-License-Identifier: LGPL-2.1-or-later
*/
#include "multiplexermodel.h"
#include <KLocalizedString>
#include "mpris2sourcemodel.h"
#include "multiplexer.h"
#include "multiplexermodel.h"
#include "playercontainer.h"
std::shared_ptr<MultiplexerModel> MultiplexerModel::self()
{
static std::weak_ptr<MultiplexerModel> s_model;
if (s_model.expired()) {
auto ptr = std::make_shared<MultiplexerModel>();
s_model = ptr;
return ptr;
}
return s_model.lock();
}
MultiplexerModel::MultiplexerModel(QObject *parent)
: QAbstractListModel(parent)
, m_multiplexer(Multiplexer::self())
{
updateActivePlayer();
/*
# Why is Qt::QueuedConnection used?
If there are only one player remaining and the last player is closed:
1. Mpris2SourceModel::rowsRemoved -> Mpris2FilterProxyModel::rowsRemoved
3. Mpris2FilterProxyModel::rowsRemoved -> Multiplexer::onRowsRemoved
4. In Multiplexer::onRowsRemoved, activePlayerIndex is updated -> Multiplexer::activePlayerIndexChanged
5. Multiplexer::activePlayerIndexChanged -> **Qt::QueuedConnection**, so MultiplexerModel::updateActivePlayer() is not called in this context。
⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️⚠️
Can't call updateActivePlayer() in the current context because updateActivePlayer() will emit rowsRemoved, which confuses Mpris2Model
because at this moment Mpris2FilterProxyModel::rowsRemoved is not finished!!! Without Qt::QueuedConnection there will be a CRASH!
💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣💣
6. After Mpris2SourceModel::rowsRemoved, the container is deleted -> PlayerContainer::destroyed
7. PlayerContainer::destroyed -> MultiplexerModel::updateActivePlayer
8. MultiplexerModel::updateActivePlayer -> (no player now) MultiplexerModel::rowsRemoved
9. The queued connection now calls MultiplexerModel::updateActivePlayer(), but there is no player now so it just simply returns.
# Why is this connection needed?
If there is more than one player, and the active player changes to another player:
1. activePlayerIndex is updated -> Multiplexer::activePlayerIndexChanged
2. Multiplexer::activePlayerIndexChanged -> **Qt::QueuedConnection**, so MultiplexerModel::updateActivePlayer() is not called in this context
3. The queued connection now calls MultiplexerModel::updateActivePlayer(), and (m_multiplexer->activePlayer().value() != m_activePlayer) is satisfied,
so a new player becomes the starred player.
*/
connect(m_multiplexer.get(), &Multiplexer::activePlayerIndexChanged, this, &MultiplexerModel::updateActivePlayer, Qt::QueuedConnection);
}
MultiplexerModel::~MultiplexerModel()
{
// MultiplexerModel is destroyed before PlayerContainer but it's not guaranteed the destroyed signal is disconnected after ~MultiplexerModel()
if (m_activePlayer) {
m_activePlayer->disconnect(this);
}
}
QVariant MultiplexerModel::data(const QModelIndex &index, int role) const
{
if (!checkIndex(index, CheckIndexOption::IndexIsValid) || !m_activePlayer) {
return {};
}
switch (role) {
case Mpris2SourceModel::IconNameRole:
return QStringLiteral("emblem-favorite");
case Mpris2SourceModel::IsMultiplexerRole:
return true;
default:
return Mpris2SourceModel::dataFromPlayer(m_activePlayer, role);
}
}
int MultiplexerModel::rowCount(const QModelIndex &parent) const
{
if (parent.isValid()) {
return 0;
}
return m_activePlayer ? 1 : 0;
}
QHash<int, QByteArray> MultiplexerModel::roleNames() const
{
return Mpris2SourceModel::self()->roleNames();
}
void MultiplexerModel::updateActivePlayer()
{
if (m_activePlayer && !m_multiplexer->activePlayer().value()) {
beginRemoveRows({}, 0, 0);
disconnect(m_activePlayer, nullptr, this, nullptr);
m_activePlayer = nullptr;
endRemoveRows();
} else if (m_multiplexer->activePlayer().value() != m_activePlayer) {
if (!m_activePlayer) {
beginInsertRows({}, 0, 0);
m_activePlayer = m_multiplexer->activePlayer().value();
endInsertRows();
} else {
disconnect(m_activePlayer, nullptr, this, nullptr);
m_activePlayer = m_multiplexer->activePlayer().value();
Q_EMIT dataChanged(index(0, 0), index(0, 0));
}
connect(m_activePlayer, &QObject::destroyed, this, &MultiplexerModel::updateActivePlayer);
// Property bindings
connect(m_activePlayer, &AbstractPlayerContainer::canControlChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::CanControlRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::trackChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::TrackRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::canGoNextChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::CanGoNextRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::canGoPreviousChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::CanGoPreviousRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::canPlayChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::CanPlayRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::canPauseChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::CanPauseRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::canStopChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::CanStopRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::canSeekChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::CanSeekRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::loopStatusChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::LoopStatusRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::playbackStatusChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::PlaybackStatusRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::positionChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::PositionRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::rateChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::RateRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::shuffleChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::ShuffleRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::volumeChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::VolumeRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::artUrlChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::ArtUrlRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::artistChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::ArtistRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::albumChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::AlbumRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::lengthChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::LengthRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::canQuitChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::CanQuitRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::canRaiseChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::CanRaiseRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::canSetFullscreenChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::CanSetFullscreenRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::desktopEntryChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::DesktopEntryRole, Mpris2SourceModel::IconNameRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::identityChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::IdentityRole});
});
connect(m_activePlayer, &AbstractPlayerContainer::kdePidChanged, this, [this] {
Q_EMIT dataChanged(index(0, 0), index(0, 0), {Mpris2SourceModel::KDEPidRole});
});
}
}
#include "moc_multiplexermodel.cpp"
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