#include "notificationstore.hpp"

#include "config/notifs.hpp"
#include "config/rootnodes.hpp"

#include <QCryptographicHash>
#include <QDateTime>
#include <QDir>
#include <QFile>
#include <QFileInfo>
#include <QFutureWatcher>
#include <QHash>
#include <QIcon>
#include <QImage>
#include <QImageReader>
#include <QJsonArray>
#include <QJsonDocument>
#include <QJsonObject>
#include <QLoggingCategory>
#include <QPainter>
#include <QBuffer>
#include <QQmlEngine>
#include <QQuickImageProvider>
#include <QSqlDatabase>
#include <QSqlError>
#include <QSqlQuery>
#include <QSqlRecord>
#include <QtConcurrent/qtconcurrentrun.h>
#include <QUuid>
#include <QUrl>

#include <algorithm>
#include <mutex>

Q_LOGGING_CATEGORY(notifLog, "ZShell.Services.notifs", QtInfoMsg)

namespace {
constexpr int MAX_ROWS = 500;
constexpr int MAX_PER_GROUP = 50;
constexpr qint64 MAX_AGE_MS = 30LL * 24 * 60 * 60 * 1000;
constexpr int TICK_MS = 250;
constexpr int MAX_IMAGE_DIM = 512;
// Memoized icon theme file lookups (hits and misses) per theme configuration.
constexpr int MAX_ICON_PATHS = 256;
constexpr qint64 PRUNE_INTERVAL_MS = 4LL * 60 * 60 * 1000;
constexpr qint64 TIME_STR_REFRESH_MS = 2000;
// Coalesces content updates (live replaces_id edits, popup state) into one
// transaction instead of one UPDATE per changed field.
constexpr int FLUSH_MS = 300;

// Quickshell serves inline notification pictures through image://qsimage/
// (and qspixmap) handles that belong to the live notification, not to the
// shell: once that notification is replaced or dismissed, the handle is gone
// and the url fails to resolve. Such a source is only ever useful as the raw
// url long enough to read the bytes, so the UI must never see it.
bool transientImageSource(const QString& source) {
	if (source.isEmpty()) {
		return false;
	}

	const QUrl url(source);
	return url.scheme() == QLatin1String("image") &&
		   (url.host() == QLatin1String("qsimage") ||
			url.host() == QLatin1String("qspixmap"));
}

// The url the UI should use: the cached blob when there is one, and the raw
// source only while that source keeps resolving.
QString displayImage(const QString& source, const QString& digest) {
	if (!digest.isEmpty()) {
		return QStringLiteral("image://notifimg/") + digest;
	}

	return transientImageSource(source) ? QString() : source;
}

// Icon theme state, captured on the GUI thread. `QIcon::themeName()`,
// `fallbackThemeName()` and `themeSearchPaths()` touch GUI-thread only state,
// but the strings they return are safe to hand to a worker.
struct IconTheme {
	QStringList searchPaths;
	QStringList themes;
	// Changes when the theme or the search paths change, so the path cache
	// below can be dropped after a theme switch.
	QString signature;
};

IconTheme iconTheme() {
	IconTheme theme;
	theme.searchPaths = QIcon::themeSearchPaths();

	for (const auto& name :
		 {QIcon::themeName(),
		  QIcon::fallbackThemeName(),
		  QStringLiteral("hicolor"),
		  QStringLiteral("Adwaita")}) {
		if (!name.isEmpty() && !theme.themes.contains(name)) {
			theme.themes.append(name);
		}
	}

	theme.signature = theme.searchPaths.join(QLatin1Char('\n')) +
					  QLatin1Char('\n') + theme.themes.join(QLatin1Char('\n'));
	return theme;
}

// Resolve an icon name to a file the theme actually ships, so notification
// images that only name an icon can still be cached. KF6's KIconLoader is not
// thread-safe (it crashed the shell when the icon provider was called from a
// worker) and QIcon painting is GUI-thread only, so this only builds candidate
// paths and stats them - which makes it worker-thread safe when the theme
// strings come from iconTheme(). Hits and misses are both memoized: a sender
// repeats the same icon name, and a name the theme lacks costs thousands of
// stat calls to discover.
QString iconFileForName(const QString& name, const IconTheme& theme) {
	if (name.isEmpty()) {
		return {};
	}

	// Stat results only change when a theme is installed or removed, which the
	// signature covers; the cap just keeps a stream of odd names bounded.
	static std::mutex cacheMutex;
	static QHash<QString, QString> pathCache;
	static QString cacheSignature;

	std::lock_guard<std::mutex> lock(cacheMutex);

	if (cacheSignature != theme.signature) {
		cacheSignature = theme.signature;
		pathCache.clear();
	}

	const auto cached = pathCache.constFind(name);
	if (cached != pathCache.constEnd()) {
		return cached.value();
	}

	const QString found = [&]() {
		if (QFileInfo::exists(name)) {
			return name;
		}

		const QFileInfo info(name);
		const QStringList names =
			info.suffix().isEmpty()
				? QStringList{name}
				: QStringList{name, info.completeBaseName()};

		static const QStringList sizes = {"256x256", "192x192",	 "128x128",
										  "96x96",	 "64x64",	 "48x48",
										  "32x32",	 "24x24",	 "22x22",
										  "16x16",	 "scalable", "256",
										  "192",	 "128",		 "96",
										  "64",		 "48",		 "32",
										  "24",		 "22",		 "16"};
		static const QStringList contexts = {
			"apps", "actions", "devices", "places", "status"};
		static const QStringList extensions = {"svg", "svgz", "png"};

		for (const auto& searchPath : theme.searchPaths) {
			for (const auto& themeName : theme.themes) {
				const QDir themeDir(QDir(searchPath).filePath(themeName));
				if (!themeDir.exists()) {
					continue;
				}

				for (const auto& candidateName : names) {
					for (const auto& size : sizes) {
						for (const auto& context : contexts) {
							for (const auto& extension : extensions) {
								const QString suffix =
									candidateName + "." + extension;

								// hicolor: <size>/<context>/<ext>/<name>.<ext>
								const QString canonical = themeDir.filePath(
									size + "/" + context + "/" + extension +
									"/" + suffix);
								if (QFileInfo::exists(canonical)) {
									return canonical;
								}

								// hicolor and Papirus both also ship
								// <size>/<context>/<name>.<ext>
								const QString sized = themeDir.filePath(
									size + "/" + context + "/" + suffix);
								if (QFileInfo::exists(sized)) {
									return sized;
								}

								// themes ordering size under context
								const QString nested = themeDir.filePath(
									context + "/" + size + "/" + suffix);
								if (QFileInfo::exists(nested)) {
									return nested;
								}
							}
						}
					}

					// theme without size directories: <context>/<name>.<ext>
					for (const auto& context : contexts) {
						for (const auto& extension : extensions) {
							const QString plain = themeDir.filePath(
								context + "/" + candidateName + "." +
								extension);
							if (QFileInfo::exists(plain)) {
								return plain;
							}
						}
					}
				}
			}
		}

		return QString();
	}();

	if (pathCache.size() >= MAX_ICON_PATHS) {
		pathCache.clear();
	}

	pathCache.insert(name, found);
	return found;
}
} // namespace

namespace ZShell::Services {

class NotifImageProvider : public QQuickImageProvider {
	public:
	explicit NotifImageProvider(const QString& dbPath)
		: QQuickImageProvider(QQuickImageProvider::Image), m_dbPath(dbPath) {}

	void setDbPath(const QString& dbPath) {
		std::lock_guard<std::mutex> lock(m_mutex);
		if (m_dbPath == dbPath) {
			return;
		}

		m_dbPath = dbPath;
		m_generation.fetch_add(1, std::memory_order_relaxed);
	}

	QImage requestImage(
		const QString& id, QSize* size, const QSize& requestedSize) override {
		if (id.isEmpty() || !openThreadDb(currentDbPath())) {
			return {};
		}

		QSqlQuery query(QSqlDatabase::database(m_threadUuid));
		query.prepare("SELECT png FROM images WHERE digest = ?");
		query.addBindValue(id);

		if (!query.exec() || !query.next()) {
			return {};
		}

		const QByteArray bytes = query.value(0).toByteArray();
		if (bytes.isEmpty()) {
			return {};
		}

		QImage image = QImage::fromData(bytes, "PNG");
		if (image.isNull()) {
			return {};
		}

		if (size) {
			*size = image.size();
		}

		if (requestedSize.isValid() && !requestedSize.isEmpty() &&
			(image.width() > requestedSize.width() ||
			 image.height() > requestedSize.height())) {
			image = image.scaled(
				requestedSize, Qt::KeepAspectRatio, Qt::SmoothTransformation);
		}

		return image;
	}

	private:
	QString currentDbPath() const {
		std::lock_guard<std::mutex> lock(m_mutex);
		return m_dbPath;
	}

	bool openThreadDb(const QString& dbPath) {
		const quint64 generation = m_generation.load(std::memory_order_relaxed);

		if (!m_threadUuid.isEmpty() && m_threadGeneration == generation) {
			return true;
		}

		if (!m_threadUuid.isEmpty()) {
			{
				auto db = QSqlDatabase::database(m_threadUuid, false);
				if (db.isValid()) {
					db.close();
				}
			}

			QSqlDatabase::removeDatabase(m_threadUuid);
			m_threadUuid.clear();
		}

		if (dbPath.isEmpty()) {
			return false;
		}

		const QString uuid = QUuid::createUuid().toString(QUuid::WithoutBraces);

		auto db = QSqlDatabase::addDatabase("QSQLITE", uuid);
		db.setConnectOptions("QSQLITE_OPEN_READONLY");
		db.setDatabaseName(dbPath);

		if (!db.open()) {
			return false;
		}

		m_threadUuid = uuid;
		m_threadGeneration = generation;
		return true;
	}

	mutable std::mutex m_mutex;
	QString m_dbPath;
	std::atomic<quint64> m_generation = 0;

	thread_local static QString m_threadUuid;
	thread_local static quint64 m_threadGeneration;
};

thread_local QString NotifImageProvider::m_threadUuid;
thread_local quint64 NotifImageProvider::m_threadGeneration;

NotificationActionRow::NotificationActionRow(
	QObject* action,
	const QString& identifier,
	const QString& text,
	QObject* parent)
	: QObject(parent)
	, m_action(action)
	, m_identifier(identifier)
	, m_text(text) {
	if (action) {
		QObject::connect(action, &QObject::destroyed, this, [this]() {
			emit invokableChanged();
		});
	}
}

bool NotificationActionRow::invokable() const {
	return m_action != nullptr;
}

QString NotificationActionRow::identifier() const {
	return m_identifier;
}

QString NotificationActionRow::text() const {
	return m_text;
}

void NotificationActionRow::invoke() {
	if (auto* action = m_action.data()) {
		QMetaObject::invokeMethod(action, "invoke");
	}
}

NotificationRow::NotificationRow(QObject* parent) : QObject(parent) {}

QQmlListProperty<NotificationActionRow> NotificationRow::actions() {
	return QQmlListProperty<NotificationActionRow>(this, &m_actions);
}

QString NotificationRow::appIcon() const {
	return m_appIcon;
}

QString NotificationRow::appName() const {
	return m_appName;
}

QString NotificationRow::body() const {
	return m_body;
}

bool NotificationRow::closed() const {
	return m_closed;
}

bool NotificationRow::hasActionIcons() const {
	return m_hasActionIcons;
}

QString NotificationRow::image() const {
	return m_image;
}

QString NotificationRow::imageSource() const {
	return m_imageSource;
}

int NotificationRow::notificationId() const {
	return m_notificationId;
}

int NotificationRow::progress() const {
	return m_progress;
}

bool NotificationRow::popup() const {
	return m_popup;
}

void NotificationRow::setPopup(bool popup) {
	if (m_popup == popup) {
		return;
	}

	m_popup = popup;
	m_popupPaused = false;
	m_deadline =
		popup ? QDateTime::currentMSecsSinceEpoch() + m_store->popupTimeout()
			  : 0;
	emit popupChanged();

	if (m_store != nullptr) {
		m_store->markDirty(this);
		m_store->updatePopupGroup(this);
	}
}

bool NotificationRow::resident() const {
	return m_resident;
}

QString NotificationRow::summary() const {
	return m_summary;
}

QDateTime NotificationRow::time() const {
	return QDateTime::fromMSecsSinceEpoch(m_timeMs);
}

QString NotificationRow::timeStr() const {
	return m_timeStr;
}

int NotificationRow::urgency() const {
	return m_urgency;
}

void NotificationRow::close() {
	if (m_closed) {
		return;
	}

	m_closed = true;
	emit closedChanged();

	if (auto* notification = m_notification.data()) {
		QMetaObject::invokeMethod(notification, "dismiss");
	}

	m_store->handleClosed(this);
}

void NotificationRow::lock(QObject* item) {
	if (item == nullptr || m_locks.contains(item)) {
		return;
	}

	m_locks.insert(item);
	// Goes through unlock() so releasing the last lock on an already-closed
	// row finishes the removal the close started. The destroyed signal
	// carries the dying object, which is the lock holder.
	QObject::connect(item, &QObject::destroyed, this, [this](QObject* obj) {
		unlock(obj);
	});
}

void NotificationRow::unlock(QObject* item) {
	m_locks.remove(item);

	if (!m_locks.isEmpty()) {
		return;
	}

	if (m_deleteAfterUnlock) {
		m_deleteAfterUnlock = false;
		deleteLater();
		return;
	}

	if (m_closed) {
		m_store->removeRow(this);
	}
}

void NotificationRow::pausePopup() {
	m_popupPaused = true;
}

void NotificationRow::resumePopup() {
	m_popupPaused = false;
}

// The v2 notification UI uses caelestia's naming; these are thin aliases of the
// existing behaviour so both spellings work.
void NotificationRow::dismiss() {
	close();
}

void NotificationRow::dismissPopup() {
	if (m_popup) {
		setPopup(false);
	}
}

void NotificationRow::holdPopup() {
	pausePopup();
}

void NotificationRow::releasePopup() {
	resumePopup();
}

void NotificationRow::ref(QObject* item) {
	lock(item);
}

void NotificationRow::unref(QObject* item) {
	unlock(item);
}

// True when path is this row's image, in either its raw or cached form, so the
// UI can tell "the same picture changed url" from "a different picture".
bool NotificationRow::isSameImage(const QString& path) const {
	return path == m_image || path == m_imageSource;
}

bool NotificationRow::isSameAppIcon(const QString& path) const {
	return path == m_appIcon;
}

bool NotificationRow::expired(qint64 now) const {
	return m_popup && !m_popupPaused && !m_closed && m_deadline > 0 &&
		   now >= m_deadline;
}

void NotificationRow::refreshTimeStr() {
	const qint64 diff = QDateTime::currentMSecsSinceEpoch() - m_timeMs;
	const qint64 m = diff / 60000;

	QString next;
	if (m < 1) {
		next = tr("now");
	} else {
		const qint64 h = m / 60;
		const qint64 d = h / 24;

		if (d > 0) {
			next = QStringLiteral("%1d").arg(d);
		} else if (h > 0) {
			next = QStringLiteral("%1h").arg(h);
		} else {
			next = QStringLiteral("%1m").arg(m);
		}
	}

	if (next != m_timeStr) {
		m_timeStr = next;
		emit timeStrChanged();
	}
}

NotificationGroup::NotificationGroup(const QString& appName, QObject* parent)
	: QObject(parent), m_appName(appName) {}

QQmlListProperty<NotificationRow> NotificationGroup::activeNotifs() {
	return QQmlListProperty<NotificationRow>(this, &m_active);
}

QString NotificationGroup::appIcon() const {
	return m_iconSource ? m_iconSource->m_appIcon : QString();
}

QString NotificationGroup::appName() const {
	return m_appName;
}

int NotificationGroup::count() const {
	return m_count;
}

QString NotificationGroup::firstSummary() const {
	return m_firstSummary;
}

QString NotificationGroup::image() const {
	return m_imageSource ? m_imageSource->m_image : QString();
}

QQmlListProperty<NotificationRow> NotificationGroup::notifs() {
	return QQmlListProperty<NotificationRow>(this, &m_notifs);
}

QString NotificationGroup::timeStr() const {
	return m_timeStr;
}

int NotificationGroup::urgency() const {
	return m_urgency;
}

void NotificationGroup::addRow(NotificationRow* row) {
	m_notifs.prepend(row);
	QObject::connect(
		row, &NotificationRow::imageChanged, this, &NotificationGroup::sync);
	QObject::connect(
		row, &NotificationRow::appIconChanged, this, &NotificationGroup::sync);
	QObject::connect(
		row, &NotificationRow::urgencyChanged, this, &NotificationGroup::sync);
	emit notifsChanged();
	refreshActive();
	sync();
}

void NotificationGroup::removeRow(NotificationRow* row) {
	const bool had = m_notifs.removeOne(row);
	if (!had) {
		return;
	}

	QObject::disconnect(row, nullptr, this, nullptr);
	emit notifsChanged();
	// Must not drop the row from m_active here: refreshActive() only emits
	// activeNotifsChanged when the list it rebuilds differs from the stored
	// one, and a silently pre-edited m_active is equal to the rebuild. The
	// popup stack reads activeNotifs, so skipping the emit left a closed row
	// occupying its slot - an invisible gap other entries did not move into.
	refreshActive();
	sync();
}

void NotificationGroup::refreshActive() {
	QList<NotificationRow*> active;
	active.reserve(m_notifs.size());
	for (auto* row : std::as_const(m_notifs)) {
		if (!row->m_closed) {
			active.append(row);
		}
	}

	if (active != m_active) {
		m_active = active;
		emit activeNotifsChanged();
	}

	if (m_count != static_cast<int>(m_active.size())) {
		m_count = static_cast<int>(m_active.size());
		emit countChanged();
	}

	NotificationRow* first = m_active.isEmpty() ? nullptr : m_active.first();

	const QString timeStr = first != nullptr ? first->m_timeStr : QString();
	if (timeStr != m_timeStr) {
		m_timeStr = timeStr;
		emit timeStrChanged();
	}

	const QString summary = first != nullptr ? first->m_summary : QString();
	if (summary != m_firstSummary) {
		m_firstSummary = summary;
		emit firstSummaryChanged();
	}
}

void NotificationGroup::sync() {
	NotificationRow* imageSource = nullptr;
	NotificationRow* iconSource = nullptr;
	int urgency = 0;

	for (auto* row : std::as_const(m_active)) {
		if (imageSource == nullptr && !row->m_image.isEmpty()) {
			imageSource = row;
		}
		if (iconSource == nullptr && !row->m_appIcon.isEmpty()) {
			iconSource = row;
		}
		urgency = (std::max)(urgency, row->m_urgency);
	}

	if (m_imageSource != imageSource) {
		m_imageSource = imageSource;
		emit imageChanged();
	}
	if (m_iconSource != iconSource) {
		m_iconSource = iconSource;
		emit appIconChanged();
	}
	if (urgency != m_urgency) {
		m_urgency = urgency;
		emit urgencyChanged();
	}
}

// Delegates compare their own shown url against the group's current source row,
// so a row swapping raw source <-> cached blob does not re-trigger the fade.
bool NotificationGroup::isSameImage(const QString& path) const {
	return m_imageSource != nullptr && m_imageSource->isSameImage(path);
}

bool NotificationGroup::isSameAppIcon(const QString& path) const {
	return m_iconSource != nullptr && m_iconSource->isSameAppIcon(path);
}

void NotificationGroup::lock(QObject* item) {
	if (item != nullptr && !m_locks.contains(item)) {
		m_locks.insert(item);
		// No Qt::UniqueConnection here: it requires a member-function pointer,
		// and the contains() check above already keeps this one-shot per item.
		QObject::connect(
			item, &QObject::destroyed, this, [this, item](QObject*) {
				unlock(item);
			});
	}
}

void NotificationGroup::unlock(QObject* item) {
	m_locks.remove(item);
	if (m_releasing && m_locks.isEmpty()) {
		deleteLater();
	}
}

// Called by the store once the group has no rows left. A delegate may still be
// animating it out, so the delete waits for its last unlock.
void NotificationGroup::release() {
	m_releasing = true;
	if (m_locks.isEmpty()) {
		deleteLater();
	}
}

NotificationStore::NotificationStore(QObject* parent)
	: QObject(parent)
	, m_uuid(QUuid::createUuid().toString(QUuid::WithoutBraces)) {
	m_tick = new QTimer(this);
	m_tick->setInterval(TICK_MS);
	QObject::connect(m_tick, &QTimer::timeout, this, &NotificationStore::tick);

	m_flush = new QTimer(this);
	m_flush->setSingleShot(true);
	m_flush->setInterval(FLUSH_MS);
	QObject::connect(m_flush, &QTimer::timeout, this, &NotificationStore::flush);

	// Config-backed settings, same pattern as TickingService: read the
	// config node directly and update live on its change signals. QML may
	// still write these properties; the next config change re-applies.
	auto* notifs = config::ConfigSingleton::instance()->notifs();
	applyNotifConfig(notifs);
	QObject::connect(
		notifs,
		&config::Notifs::defaultExpireTimeoutChanged,
		this,
		[this, notifs] { applyNotifConfig(notifs); });
	QObject::connect(
		notifs, &config::Notifs::expireChanged, this, [this, notifs] {
			applyNotifConfig(notifs);
		});
}

NotificationStore::~NotificationStore() {
	flush();
	closeDb();
}

QString NotificationStore::path() const {
	return m_path;
}

void NotificationStore::setPath(const QString& path) {
	if (m_path == path || path.isEmpty()) {
		return;
	}

	m_path = path;
	emit pathChanged();

	if (!openDb()) {
		return;
	}

	migrateLegacyJson();
	prune();
	loadRows();
	qCInfo(notifLog) << "NotificationStore: ready with" << m_rows.size()
					 << "stored rows from" << m_path;

	const qint64 now = QDateTime::currentMSecsSinceEpoch();
	m_nextPrune = now + PRUNE_INTERVAL_MS;

	m_tick->start();
}

int NotificationStore::popupTimeout() const {
	return m_popupTimeout;
}

void NotificationStore::setPopupTimeout(int timeout) {
	if (m_popupTimeout == timeout || timeout <= 0) {
		return;
	}

	m_popupTimeout = timeout;
	emit popupTimeoutChanged();
}

bool NotificationStore::autoExpire() const {
	return m_autoExpire;
}

void NotificationStore::setAutoExpire(bool autoExpire) {
	if (m_autoExpire == autoExpire) {
		return;
	}

	m_autoExpire = autoExpire;
	emit autoExpireChanged();
}

void NotificationStore::applyNotifConfig(const config::Notifs* notifs) {
	setPopupTimeout(notifs->defaultExpireTimeout());
	setAutoExpire(notifs->expire());
}

QQmlListProperty<NotificationRow> NotificationStore::rows() {
	return QQmlListProperty<NotificationRow>(this, &m_rows);
}

QQmlListProperty<NotificationGroup> NotificationStore::groups() {
	return QQmlListProperty<NotificationGroup>(this, &m_groups);
}

QQmlListProperty<NotificationGroup> NotificationStore::popupGroups() {
	return QQmlListProperty<NotificationGroup>(this, &m_popupGroups);
}

NotificationRow* NotificationStore::insert(
	const QJSValue& notification, bool popup) {
	const auto wrapped = notification.toVariant().value<QObject*>();
	if (wrapped == nullptr) {
		qWarning(notifLog) << "NotificationStore: expected a Notification";
		return nullptr;
	}

	const int notificationId = wrapped->property("id").toInt();

	if (wrapped->property("lastGeneration").toBool()) {
		if (auto* row = rowForNotificationId(notificationId)) {
			attachNotification(row, wrapped, notification);
			return row;
		}
	}

	auto* row = new NotificationRow(this);
	row->m_store = this;
	row->m_timeMs = QDateTime::currentMSecsSinceEpoch();
	row->m_notificationId = notificationId;
	copyFields(row, wrapped);

	const auto hints = notification.property("hints");
	if (hints.isObject()) {
		row->m_progress = hints.property("value").toVariant().toInt();
	}

	attachNotification(row, wrapped, notification);

	row->m_popup = popup;
	if (popup) {
		row->m_deadline = QDateTime::currentMSecsSinceEpoch() + m_popupTimeout;
	}

	insertDbRow(row);
	startImageCache(row);

	m_rows.prepend(row);
	addGroup(row);
	if (popup) {
		addPopupGroup(row);
	}
	row->refreshTimeStr();
	scheduleRowsChanged();

	return row;
}

void NotificationStore::scheduleRowsChanged() {
	if (m_rowsSignalPending) {
		return;
	}

	m_rowsSignalPending = true;
	QTimer::singleShot(0, this, [this] {
		if (!m_rowsSignalPending) {
			return; // an immediate emit (e.g. clear()) already covered it
		}
		m_rowsSignalPending = false;
		emit rowsChanged();
	});
}

void NotificationStore::clear() {
	m_flush->stop();
	m_dirty.clear();

	const auto db = QSqlDatabase::database(m_uuid, false);
	if (db.isOpen()) {
		QSqlQuery query(db);
		query.prepare("DELETE FROM notifications");
		if (!query.exec()) {
			qWarning(notifLog)
				<< "NotificationStore: could not clear notifications"
				<< query.lastError();
		}
	}

	// The bulk delete above already removed every DB row; the per-row
	// cleanup would just re-delete no-ops, so batch it instead.
	m_clearing = true;
	const auto rows = m_rows;
	for (auto* row : rows) {
		row->close();
	}
	m_clearing = false;

	orphanCleanup();
	m_rowsSignalPending = false; // supersede any pending coalesced emit
	emit rowsChanged();
}

void NotificationStore::copyFields(NotificationRow* row, QObject* notification) {
	row->m_summary = notification->property("summary").toString();
	row->m_body = notification->property("body").toString();
	row->m_appName = notification->property("appName").toString();
	row->m_appIcon = notification->property("appIcon").toString();
	row->m_imageSource = notification->property("image").toString();
	row->m_image = displayImage(row->m_imageSource, row->m_digest);
	row->m_resident = notification->property("resident").toBool();
	row->m_hasActionIcons = notification->property("hasActionIcons").toBool();
	row->m_urgency = notification->property("urgency").toInt();
}

void NotificationStore::attachNotification(
	NotificationRow* row, QObject* notification, const QJSValue& js) {
	row->m_notification = notification;
	row->m_jsNotification = js;
	m_liveRows.insert(notification, row);

	if (!row->m_liveConnected) {
		row->m_liveConnected = true;
		const QPointer<NotificationRow> rowGuard(row);
		QObject::connect(
			notification,
			&QObject::destroyed,
			this,
			[this, rowGuard, notification]() {
				m_liveRows.remove(notification);

				if (rowGuard == nullptr || rowGuard->m_closed) {
					return;
				}

				rowGuard->m_closed = true;
				emit rowGuard->closedChanged();
				rowGuard->m_store->handleClosed(rowGuard);
			});

		// Quickshell applies replaces_id updates to the object we already
		// hold; mirror those changes onto the row (in UI and in the DB).
		// Connected straight to the slot (not through an intermediate
		// signal) so sender() in handleLiveUpdate is the Notification.
		static const QMetaMethod slot = [] {
			const QMetaObject& storeMeta = NotificationStore::staticMetaObject;
			return storeMeta.method(
				storeMeta.indexOfSlot("handleLiveUpdate()"));
		}();
		static const QList<QByteArray> mirrored = {
			"summaryChanged",
			"bodyChanged",
			"appNameChanged",
			"appIconChanged",
			"imageChanged",
			"urgencyChanged",
			"residentChanged",
			"hasActionIconsChanged",
			"actionsChanged",
			"hintsChanged",
		};

		const auto* meta = notification->metaObject();
		for (int i = 0; i < meta->methodCount(); i++) {
			const auto method = meta->method(i);
			if (method.methodType() != QMetaMethod::Signal) {
				continue;
			}

			if (mirrored.contains(method.name())) {
				QObject::connect(notification, method, this, slot);
			}
		}
	}

	qDeleteAll(row->m_actions);
	row->m_actions.clear();
	row->m_actions = parseActions(js.property("actions"), row);
	emit row->actionsChanged();
}

void NotificationStore::handleLiveUpdate() {
	const auto it = m_liveRows.constFind(sender());
	if (it == m_liveRows.constEnd()) {
		qWarning(notifLog) << "NotificationStore: live update for untracked "
							  "notification object";
		return;
	}

	NotificationRow* row = it.value();

	const QString summary = it.key()->property("summary").toString();
	const QString body = it.key()->property("body").toString();
	const QString appName = it.key()->property("appName").toString();
	const QString appIcon = it.key()->property("appIcon").toString();
	const QString imageSource = it.key()->property("image").toString();
	const bool resident = it.key()->property("resident").toBool();
	const bool hasActionIcons = it.key()->property("hasActionIcons").toBool();
	const int urgency = it.key()->property("urgency").toInt();

	const bool imageChanged = imageSource != row->m_imageSource;

	if (summary != row->m_summary) {
		row->m_summary = summary;
		emit row->summaryChanged();
	}
	if (body != row->m_body) {
		row->m_body = body;
		emit row->bodyChanged();
	}
	if (appName != row->m_appName) {
		row->m_appName = appName;
		emit row->appNameChanged();
	}
	if (appIcon != row->m_appIcon) {
		row->m_appIcon = appIcon;
		emit row->appIconChanged();
	}
	if (urgency != row->m_urgency) {
		row->m_urgency = urgency;
		emit row->urgencyChanged();
	}
	if (resident != row->m_resident) {
		row->m_resident = resident;
		emit row->residentChanged();
	}
	if (hasActionIcons != row->m_hasActionIcons) {
		row->m_hasActionIcons = hasActionIcons;
		emit row->hasActionIconsChanged();
	}

	const auto hints = row->m_jsNotification.property("hints");
	if (hints.isObject()) {
		const int progress = hints.property("value").toVariant().toInt();
		if (progress != row->m_progress) {
			row->m_progress = progress;
			emit row->progressChanged();
		}
	}

	qDeleteAll(row->m_actions);
	row->m_actions.clear();
	row->m_actions =
		parseActions(row->m_jsNotification.property("actions"), row);
	emit row->actionsChanged();

	if (imageChanged) {
		row->m_imageSource = imageSource;
		row->m_digest.clear();
		row->m_image = displayImage(imageSource, row->m_digest);
		emit row->imageSourceChanged();
		emit row->imageChanged();
		startImageCache(row);
	}

	// New content deserves a full look: restart the popup countdown.
	if (row->m_popup) {
		row->m_deadline = QDateTime::currentMSecsSinceEpoch() + m_popupTimeout;
	}

	// The row may have moved to another app name (replaces_id can change it).
	if (row->m_group != nullptr && row->m_group->m_appName != row->m_appName) {
		removeGroupRow(row);
		addGroup(row);

		if (row->m_popupGroup != nullptr) {
			removePopupGroupRow(row);
			addPopupGroup(row);
		}
	}

	markDirty(row);
}

void NotificationStore::updateDbRow(NotificationRow* row) {
	if (row->m_rowId < 0) {
		return;
	}

	const auto db = QSqlDatabase::database(m_uuid, false);
	if (!db.isOpen()) {
		return;
	}

	QJsonArray actions;
	for (auto* action : std::as_const(row->m_actions)) {
		actions.append(
			QJsonObject{
				{"identifier", action->identifier()},
				{"text", action->text()}});
	}

	QSqlQuery query(db);
	query.prepare(
		"UPDATE notifications SET"
		" app_name = ?, app_icon = ?, summary = ?, body = ?,"
		" urgency = ?, resident = ?, has_action_icons = ?, popup = ?,"
		" actions = ?, image_source = ?, image_digest = ?, progress = ?"
		" WHERE id = ?");
	query.addBindValue(row->m_appName);
	query.addBindValue(row->m_appIcon);
	query.addBindValue(row->m_summary);
	query.addBindValue(row->m_body);
	query.addBindValue(row->m_urgency);
	query.addBindValue(row->m_resident ? 1 : 0);
	query.addBindValue(row->m_hasActionIcons ? 1 : 0);
	query.addBindValue(row->m_popup ? 1 : 0);
	query.addBindValue(
		QString::fromUtf8(
			QJsonDocument(actions).toJson(QJsonDocument::Compact)));
	query.addBindValue(row->m_imageSource);
	query.addBindValue(row->m_digest);
	query.addBindValue(row->m_progress);
	query.addBindValue(row->m_rowId);

	if (!query.exec()) {
		qWarning(notifLog) << "NotificationStore: could not update row"
						   << query.lastError();
	}
}

QList<NotificationActionRow*> NotificationStore::parseActions(
	const QJSValue& actions, NotificationRow* row) {
	QList<NotificationActionRow*> result;

	if (!actions.isObject()) {
		return result;
	}

	const int length = actions.property("length").toVariant().toInt();
	for (int i = 0; i < length; i++) {
		auto* object = actions.property(static_cast<quint32>(i))
						   .toVariant()
						   .value<QObject*>();
		if (object == nullptr) {
			continue;
		}

		result.append(new NotificationActionRow(
			object,
			object->property("identifier").toString(),
			object->property("text").toString(),
			row));
	}

	return result;
}

NotificationRow* NotificationStore::rowForNotificationId(int id) const {
	for (auto* row : m_rows) {
		if (row->m_notificationId == id && !row->m_closed) {
			return row;
		}
	}

	return nullptr;
}

void NotificationStore::handleClosed(NotificationRow* row) {
	// During clear() the bulk DELETE already removed every row.
	if (m_clearing) {
		removeRow(row);
		return;
	}

	const auto db = QSqlDatabase::database(m_uuid, false);
	if (db.isOpen()) {
		QSqlQuery query(db);
		query.prepare("DELETE FROM notifications WHERE id = ?");
		query.addBindValue(row->m_rowId);
		query.exec();
	}

	m_dirty.remove(row);
	removePopupGroupRow(row);

	if (row->m_group != nullptr) {
		row->m_group->refreshActive();
		row->m_group->sync();
	}

	// A closed row leaves the store immediately, so its group and the sidebar
	// order update at once; a delegate that still holds it only delays the
	// delete, never the removal.
	removeRow(row);
}

void NotificationStore::removeRow(NotificationRow* row) {
	if (!m_rows.removeOne(row)) {
		return;
	}

	removePopupGroupRow(row);
	removeGroupRow(row);
	m_dirty.remove(row);

	// The row is gone; drop any live-notification mapping to it so
	// handleLiveUpdate can never resolve a freed pointer.
	erase_if(m_liveRows, [row](std::pair<const QObject*, NotificationRow*> e) {
		return e.second == row;
	});

	// A delegate animating this row out still holds it; unlock() deletes once
	// the last lock is gone.
	if (row->m_locks.isEmpty()) {
		row->deleteLater();
	} else {
		row->m_deleteAfterUnlock = true;
	}

	if (!m_clearing) {
		orphanCleanup();
		scheduleRowsChanged();
	}
}

void NotificationStore::markDirty(NotificationRow* row) {
	if (row->m_rowId < 0) {
		return;
	}

	m_dirty.insert(row);
	m_flush->start();
}

void NotificationStore::flush() {
	m_flush->stop();
	if (m_dirty.isEmpty()) {
		return;
	}

	auto db = QSqlDatabase::database(m_uuid, false);
	if (!db.isOpen()) {
		m_dirty.clear();
		return;
	}

	if (!db.transaction()) {
		qWarning(notifLog) << "NotificationStore: flush transaction failed"
						   << db.lastError();
	}

	for (auto* row : std::as_const(m_dirty)) {
		updateDbRow(row);
	}
	m_dirty.clear();

	if (!db.commit()) {
		qWarning(notifLog) << "NotificationStore: flush commit failed"
						   << db.lastError();
	}
}

void NotificationStore::addGroup(NotificationRow* row) {
	auto* group = m_groupsByName.value(row->m_appName, nullptr);

	if (group == nullptr) {
		group = new NotificationGroup(row->m_appName, this);
		m_groupsByName.insert(row->m_appName, group);
		m_groups.prepend(group);
		emit groupsChanged();
	} else {
		// Most-recently-active group first, matching the sidebar order.
		const qsizetype index = m_groups.indexOf(group);
		if (index > 0) {
			m_groups.move(index, 0);
			emit groupsChanged();
		}
	}

	row->m_group = group;
	group->addRow(row);
}

void NotificationStore::removeGroupRow(NotificationRow* row) {
	auto* group = row->m_group;
	if (group == nullptr) {
		return;
	}

	row->m_group = nullptr;
	group->removeRow(row);

	if (!group->m_notifs.isEmpty()) {
		return;
	}

	m_groups.removeOne(group);
	m_groupsByName.remove(group->m_appName);
	group->release();
	emit groupsChanged();
}

// Popup groups mirror m_groups over the rows currently showing as popups, so
// the popup stack can render one card per app instead of one per notification.
void NotificationStore::addPopupGroup(NotificationRow* row) {
	if (row->m_popupGroup != nullptr) {
		return;
	}

	auto* group = m_popupGroupsByName.value(row->m_appName, nullptr);

	if (group == nullptr) {
		group = new NotificationGroup(row->m_appName, this);
		m_popupGroupsByName.insert(row->m_appName, group);
		m_popupGroups.prepend(group);
		emit popupGroupsChanged();
	} else {
		const qsizetype index = m_popupGroups.indexOf(group);
		if (index > 0) {
			m_popupGroups.move(index, 0);
			emit popupGroupsChanged();
		}
	}

	row->m_popupGroup = group;
	group->addRow(row);
}

void NotificationStore::removePopupGroupRow(NotificationRow* row) {
	auto* group = row->m_popupGroup;
	if (group == nullptr) {
		return;
	}

	row->m_popupGroup = nullptr;
	group->removeRow(row);

	if (!group->m_notifs.isEmpty()) {
		return;
	}

	m_popupGroups.removeOne(group);
	m_popupGroupsByName.remove(group->m_appName);
	group->release();
	emit popupGroupsChanged();
}

void NotificationStore::updatePopupGroup(NotificationRow* row) {
	if (row->m_popup && !row->m_closed) {
		addPopupGroup(row);
		return;
	}

	removePopupGroupRow(row);
}

void NotificationStore::insertDbRow(NotificationRow* row) {
	const auto db = QSqlDatabase::database(m_uuid, false);
	if (!db.isOpen()) {
		return;
	}

	QJsonArray actions;
	for (auto* action : std::as_const(row->m_actions)) {
		actions.append(
			QJsonObject{
				{"identifier", action->identifier()},
				{"text", action->text()}});
	}

	QSqlQuery query(db);
	query.prepare(
		"INSERT INTO notifications"
		" (notification_id, app_name, app_icon, summary, body, time,"
		" urgency, resident, has_action_icons, popup, actions,"
		" image_source, image_digest, progress)"
		" VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)");
	query.addBindValue(row->m_notificationId);
	query.addBindValue(row->m_appName);
	query.addBindValue(row->m_appIcon);
	query.addBindValue(row->m_summary);
	query.addBindValue(row->m_body);
	query.addBindValue(row->m_timeMs);
	query.addBindValue(row->m_urgency);
	query.addBindValue(row->m_resident ? 1 : 0);
	query.addBindValue(row->m_hasActionIcons ? 1 : 0);
	query.addBindValue(row->m_popup ? 1 : 0);
	query.addBindValue(
		QString::fromUtf8(
			QJsonDocument(actions).toJson(QJsonDocument::Compact)));
	query.addBindValue(row->m_imageSource);
	query.addBindValue(row->m_digest);
	query.addBindValue(row->m_progress);

	if (!query.exec()) {
		qWarning(notifLog) << "NotificationStore: could not insert row"
						   << query.lastError();
		return;
	}

	row->m_rowId = query.lastInsertId().toLongLong();
}

bool NotificationStore::openDb() {
	closeDb();

	QDir().mkpath(QFileInfo(m_path).absolutePath());

	auto db = QSqlDatabase::addDatabase("QSQLITE", m_uuid);
	db.setDatabaseName(m_path);

	if (!db.open()) {
		qWarning(notifLog) << "NotificationStore: could not open database"
						   << m_path << db.lastError();
		return false;
	}

	QSqlQuery query(db);
	const QStringList statements = {
		// WAL + NORMAL: commits don't fsync per insert (the fsync is what
		// made every notification insert 5-8ms). Safe with WAL: an
		// application crash still recovers the WAL; only an OS/power
		// failure can lose the most recent commits.
		"PRAGMA journal_mode=WAL",
		"PRAGMA synchronous=NORMAL",
		"CREATE TABLE IF NOT EXISTS notifications("
		"id INTEGER PRIMARY KEY AUTOINCREMENT,"
		" notification_id INTEGER, app_name TEXT, app_icon TEXT,"
		" summary TEXT, body TEXT, time INTEGER, urgency INTEGER,"
		" resident INTEGER, has_action_icons INTEGER, popup INTEGER,"
		" actions TEXT, image_source TEXT, image_digest TEXT,"
		" progress INTEGER)",
		"CREATE TABLE IF NOT EXISTS images("
		"digest TEXT PRIMARY KEY, png BLOB)",
		"CREATE INDEX IF NOT EXISTS notifications_time"
		" ON notifications(time DESC)",
	};

	for (const auto& statement : statements) {
		if (!query.exec(statement)) {
			qWarning(notifLog)
				<< "NotificationStore: could not prepare database schema"
				<< statement << query.lastError();
			closeDb();
			return false;
		}
	}

	// Databases created before progress was stored lack the column; ALTER adds
	// it instead of dropping history (caelestia drops and recreates).
	if (!db.record("notifications").contains("progress")) {
		QSqlQuery alter(db);
		if (!alter.exec(
				"ALTER TABLE notifications ADD COLUMN progress INTEGER")) {
			qWarning(notifLog)
				<< "NotificationStore: could not add progress column"
				<< alter.lastError();
			closeDb();
			return false;
		}
	}

	if (m_provider != nullptr) {
		m_provider->setDbPath(m_path);
		return true;
	}

	registerProvider();
	return true;
}

void NotificationStore::orphanCleanup() {
	const auto db = QSqlDatabase::database(m_uuid, false);
	if (!db.isOpen()) {
		return;
	}

	QSqlQuery query(db);
	if (!query.exec(
			"DELETE FROM images WHERE digest NOT IN"
			" (SELECT DISTINCT image_digest FROM notifications"
			" WHERE image_digest != '')")) {
		qWarning(notifLog)
			<< "NotificationStore: could not clean up orphaned images"
			<< query.lastError();
	}
}

void NotificationStore::registerProvider() {
	if (m_provider != nullptr) {
		return;
	}

	auto* engine = qmlEngine(this);
	if (engine == nullptr) {
		return;
	}

	m_provider = new NotifImageProvider(m_path);
	engine->addImageProvider(QStringLiteral("notifimg"), m_provider);
}

void NotificationStore::closeDb() {
	if (!QSqlDatabase::contains(m_uuid)) {
		return;
	}

	{
		auto db = QSqlDatabase::database(m_uuid, false);
		if (db.isValid()) {
			db.close();
		}
	}

	QSqlDatabase::removeDatabase(m_uuid);
}

void NotificationStore::loadRows() {
	const auto db = QSqlDatabase::database(m_uuid, false);
	if (!db.isOpen()) {
		return;
	}

	QSqlQuery query(db);
	query.exec(
		"SELECT id, notification_id, app_name, app_icon, summary, body, time,"
		" urgency, resident, has_action_icons, popup, actions,"
		" image_source, image_digest, progress"
		" FROM notifications ORDER BY time DESC");

	while (query.next()) {
		auto* row = new NotificationRow(this);
		row->m_store = this;
		row->m_rowId = query.value(0).toLongLong();
		row->m_notificationId = query.value(1).toInt();
		row->m_appName = query.value(2).toString();
		row->m_appIcon = query.value(3).toString();
		row->m_summary = query.value(4).toString();
		row->m_body = query.value(5).toString();
		row->m_timeMs = query.value(6).toLongLong();
		row->m_urgency = query.value(7).toInt();
		row->m_resident = query.value(8).toInt() != 0;
		row->m_hasActionIcons = query.value(9).toInt() != 0;
		// Popup state is deliberately not restored: showing stored
		// notifications as toasts again after a shell restart would
		// replay an old burst, and with autoExpire off the flag never
		// clears itself. The rows stay in the sidebar instead.
		row->m_popup = false;
		row->m_imageSource = query.value(12).toString();
		row->m_digest = query.value(13).toString();
		row->m_progress = query.value(14).toInt();

		const auto actions =
			QJsonDocument::fromJson(query.value(11).toString().toUtf8());
		if (actions.isArray()) {
			for (const auto& action : actions.array()) {
				const auto object = action.toObject();
				row->m_actions.append(new NotificationActionRow(
					nullptr,
					object.value("identifier").toString(),
					object.value("text").toString(),
					row));
			}
		}

		row->m_image = displayImage(row->m_imageSource, row->m_digest);
		row->refreshTimeStr();

		if (row->m_digest.isEmpty()) {
			startImageCache(row);
		}

		m_rows.append(row);
		addGroup(row);
	}

	emit rowsChanged();
}

void NotificationStore::migrateLegacyJson() {
	const QString legacy =
		QDir(QFileInfo(m_path).absolutePath()).filePath("notifs.json");

	const auto db = QSqlDatabase::database(m_uuid, false);
	if (!db.isOpen() || !QFile::exists(legacy)) {
		return;
	}

	QSqlQuery count(db);
	count.exec("SELECT COUNT(*) FROM notifications");
	if (count.next() && count.value(0).toInt() != 0) {
		return;
	}

	QFile file(legacy);
	if (!file.open(QIODevice::ReadOnly)) {
		return;
	}

	const auto doc = QJsonDocument::fromJson(file.readAll());
	if (!doc.isArray()) {
		return;
	}

	for (const auto& value : doc.array()) {
		const auto object = value.toObject();

		auto* row = new NotificationRow(this);
		row->m_store = this;
		row->m_appName = object.value("appName").toString();
		row->m_appIcon = object.value("appIcon").toString();
		row->m_summary = object.value("summary").toString();
		row->m_body = object.value("body").toString();
		row->m_imageSource = object.value("image").toString();
		row->m_notificationId = object.value("id").toInt();
		row->m_urgency = object.value("urgency").toInt(1);
		row->m_resident = object.value("resident").toBool();
		row->m_hasActionIcons = object.value("hasActionIcons").toBool();
		// Same reasoning as loadRows(): never re-toast migrated rows.
		row->m_popup = false;

		const auto time = object.value("time");
		if (time.isDouble()) {
			row->m_timeMs = static_cast<qint64>(time.toDouble());
		} else {
			const auto parsed =
				QDateTime::fromString(time.toString(), Qt::ISODate);
			row->m_timeMs = parsed.isValid()
								? parsed.toMSecsSinceEpoch()
								: QDateTime::currentMSecsSinceEpoch();
		}

		for (const auto& action : object.value("actions").toArray()) {
			const auto actionObject = action.toObject();
			row->m_actions.append(new NotificationActionRow(
				nullptr,
				actionObject.value("identifier").toString(),
				actionObject.value("text").toString(),
				row));
		}

		row->m_image = displayImage(row->m_imageSource, row->m_digest);

		row->refreshTimeStr();
		insertDbRow(row);
		startImageCache(row);
		m_rows.append(row);
		addGroup(row);
	}

	if (!m_rows.isEmpty()) {
		emit rowsChanged();
	}

	file.close();
	QFile::remove(legacy + ".migrated");
	QFile::rename(legacy, legacy + ".migrated");
	qCInfo(notifLog) << "NotificationStore: migrated legacy notifs.json";
}

void NotificationStore::prune() {
	flush();

	const auto db = QSqlDatabase::database(m_uuid, false);
	if (!db.isOpen()) {
		return;
	}

	QSqlQuery query(db);
	query.prepare("DELETE FROM notifications WHERE time < ?");
	query.addBindValue(QDateTime::currentMSecsSinceEpoch() - MAX_AGE_MS);
	if (!query.exec()) {
		qWarning(notifLog)
			<< "NotificationStore: could not prune old notifications"
			<< query.lastError();
	}

	// Total cap, preferring higher urgency so a chatty app cannot push out
	// an important notification.
	if (!query.exec(
			"DELETE FROM notifications WHERE id NOT IN"
			" (SELECT id FROM notifications ORDER BY urgency DESC, time DESC"
			" LIMIT " +
			QString::number(MAX_ROWS) + ")")) {
		qWarning(notifLog)
			<< "NotificationStore: could not trim notification rows"
			<< query.lastError();
	}

	// Per-app cap: one app flooding must not crowd out the other groups.
	QStringList appNames;
	if (query.exec("SELECT DISTINCT app_name FROM notifications")) {
		while (query.next()) {
			appNames.append(query.value(0).toString());
		}
	}

	for (const auto& appName : std::as_const(appNames)) {
		QSqlQuery perGroup(db);
		perGroup.prepare(
			"DELETE FROM notifications WHERE app_name = ? AND id NOT IN"
			" (SELECT id FROM notifications WHERE app_name = ?"
			" ORDER BY urgency DESC, time DESC LIMIT " +
			QString::number(MAX_PER_GROUP) + ")");
		perGroup.addBindValue(appName);
		perGroup.addBindValue(appName);

		if (!perGroup.exec()) {
			qWarning(notifLog) << "NotificationStore: could not trim group"
							   << appName << perGroup.lastError();
		}
	}

	orphanCleanup();
	trimRows();
}

void NotificationStore::trimRows() {
	if (m_rows.size() <= MAX_ROWS) {
		return;
	}

	// Only closed, unlocked rows are droppable (open rows may still be
	// acted on by the sender). Weakest first: lowest urgency, then oldest.
	const auto db = QSqlDatabase::database(m_uuid, false);

	while (m_rows.size() > MAX_ROWS) {
		NotificationRow* victim = nullptr;

		for (auto* row : std::as_const(m_rows)) {
			if (!row->m_closed || !row->m_locks.isEmpty()) {
				continue;
			}

			if (victim == nullptr) {
				victim = row;
				continue;
			}

			const bool weaker = row->m_urgency < victim->m_urgency ||
								(row->m_urgency == victim->m_urgency &&
								 row->m_timeMs <= victim->m_timeMs);
			if (weaker) {
				victim = row;
			}
		}

		if (victim == nullptr) {
			return;
		}

		if (victim->m_rowId >= 0 && db.isOpen()) {
			QSqlQuery query(db);
			query.prepare("DELETE FROM notifications WHERE id = ?");
			query.addBindValue(victim->m_rowId);
			query.exec();
		}

		removeRow(victim);
	}
}

void NotificationStore::startImageCache(NotificationRow* row) {
	if (row->m_imageSource.isEmpty()) {
		return;
	}

	registerProvider();

	const QUrl url(row->m_imageSource);

	// Resolve *what* to read on the main thread (engine provider lookups and
	// QIcon's theme state belong here), but do no file scanning and no
	// decoding here: providers are designed to serve requestImage from non-GUI
	// threads, and SVG rasterization was blocking the shell 3-9ms per
	// notification.
	QString localPath;
	QQuickImageProvider* provider = nullptr;
	QString providerId;
	bool usePixmap = false;
	QImage inlineImage;
	QString iconName;
	IconTheme theme;

	if (url.isLocalFile()) {
		localPath = url.toLocalFile();
	} else if (url.scheme() == QLatin1String("image")) {
		const QString id = url.path().startsWith(QLatin1Char('/'))
							   ? url.path().mid(1)
							   : url.path();
		const QString host = url.host();

		if (host != QLatin1String("qsimage") &&
			host != QLatin1String("qspixmap")) {
			// Provider urls such as image://icon/... are served by KF6's
			// KIconLoader, which is not thread-safe (calling it from a
			// worker crashed the shell). Only QIcon's theme state is read
			// here, because the GUI thread owns it; the candidate scanning it
			// feeds is pure filesystem work and runs in the worker below. A
			// name the theme does not have means thousands of stat calls, and
			// doing those here stalled inserts for milliseconds. If nothing
			// matches, the row keeps rendering the url directly.
			iconName = id;
			theme = iconTheme();
		} else {
			// Transient inline notification images (image://qsimage/...).
			// Provider objects are engine-owned and outlive this task;
			// ids owned by a destroyed notification resolve to nothing.
			auto* engine = qmlEngine(this);
			if (engine == nullptr) {
				return;
			}

			auto* base = const_cast<QQmlImageProviderBase*>(
				engine->imageProvider(url.host()));
			provider = dynamic_cast<QQuickImageProvider*>(base);
			if (provider == nullptr) {
				return;
			}

			providerId = id;

			switch (provider->imageType()) {
			case QQuickImageProvider::Image:
				usePixmap = false;
				break;
			case QQuickImageProvider::Pixmap:
				usePixmap = true;
				break;
			default:
				return;
			}

			// Copy the pixels here instead of in the worker: the handle
			// belongs to the sender's notification, and it can be gone by the
			// time the task runs, which silently dropped the picture. This is
			// a memory copy of an already decoded image, not a rasterization.
			inlineImage =
				usePixmap
					? provider->requestPixmap(providerId, nullptr, QSize())
						  .toImage()
					: provider->requestImage(providerId, nullptr, QSize());
			if (inlineImage.isNull()) {
				return;
			}
		}
	}

	const QPointer<NotificationRow> guard(row);

	auto* watcher = new QFutureWatcher<std::pair<QString, QByteArray>>(this);
	QObject::connect(
		watcher,
		&QFutureWatcher<std::pair<QString, QByteArray>>::finished,
		this,
		[this, watcher, guard]() {
			const auto result = watcher->result();
			if (!result.first.isEmpty()) {
				storeImageBlob(guard, result.first, result.second);
			}

			watcher->deleteLater();
		});

	watcher->setFuture(
		QtConcurrent::run([localPath,
						   iconName,
						   theme,
						   provider,
						   providerId,
						   usePixmap,
						   inlineImage]() {
			QImage image = inlineImage;
			QString path = localPath;

			if (image.isNull() && path.isEmpty() && !iconName.isEmpty()) {
				path = iconFileForName(iconName, theme);
			}

			if (image.isNull() && !path.isEmpty()) {
				QImageReader reader(path);
				reader.setAutoTransform(true);
				image = reader.read();
			} else if (image.isNull() && provider != nullptr) {
				image =
					usePixmap
						? provider->requestPixmap(providerId, nullptr, QSize())
							  .toImage()
						: provider->requestImage(providerId, nullptr, QSize());
			}

			if (image.isNull()) {
				return std::pair<QString, QByteArray>();
			}

			QImage normalized = image;
			if (normalized.width() > MAX_IMAGE_DIM ||
				normalized.height() > MAX_IMAGE_DIM) {
				normalized = normalized.scaled(
					MAX_IMAGE_DIM,
					MAX_IMAGE_DIM,
					Qt::KeepAspectRatio,
					Qt::SmoothTransformation);
			}

			normalized = normalized.convertToFormat(QImage::Format_RGBA8888);

			// Cache the avatar content already cut to a circle, so the view
			// does not have to mask it with a layer effect every frame.
			const int side =
				(std::min)(normalized.width(), normalized.height());
			const QRect square(
				(normalized.width() - side) / 2,
				(normalized.height() - side) / 2,
				side,
				side);
			QImage circle(side, side, QImage::Format_RGBA8888);
			circle.fill(Qt::transparent);

			QImage mask(side, side, QImage::Format_ARGB32);
			mask.fill(Qt::transparent);
			{
				QPainter maskPainter(&mask);
				maskPainter.setRenderHint(QPainter::Antialiasing);
				maskPainter.setPen(Qt::NoPen);
				maskPainter.setBrush(QColor(0, 0, 0, 255));
				maskPainter.drawEllipse(QRect(0, 0, side, side));
			}

			{
				QPainter painter(&circle);
				painter.setCompositionMode(QPainter::CompositionMode_Source);
				painter.drawImage(QRect(0, 0, side, side), normalized, square);
				painter.setCompositionMode(
					QPainter::CompositionMode_DestinationIn);
				painter.drawImage(0, 0, mask);
			}

			normalized = circle;

			const QByteArray bytes(
				reinterpret_cast<const char*>(normalized.constBits()),
				normalized.sizeInBytes());

			const QString digest = QString::fromLatin1(
				QCryptographicHash::hash(bytes, QCryptographicHash::Sha256)
					.toHex());

			QByteArray png;
			QBuffer buffer(&png);
			if (!buffer.open(QIODevice::WriteOnly) ||
				!normalized.save(&buffer, "PNG")) {
				return std::pair<QString, QByteArray>();
			}

			return std::make_pair(digest, png);
		}));
}

void NotificationStore::storeImageBlob(
	const QPointer<NotificationRow>& row,
	const QString& digest,
	const QByteArray& png) {
	const auto db = QSqlDatabase::database(m_uuid, false);
	if (!db.isOpen()) {
		return;
	}

	QSqlQuery query(db);
	query.prepare(
		"INSERT INTO images (digest, png) VALUES (?, ?)"
		" ON CONFLICT(digest) DO NOTHING");
	query.addBindValue(digest);
	query.addBindValue(png);
	query.exec();

	if (row != nullptr) {
		if (row->m_rowId >= 0) {
			QSqlQuery update(db);
			update.prepare(
				"UPDATE notifications SET image_digest = ?"
				" WHERE id = ?");
			update.addBindValue(digest);
			update.addBindValue(row->m_rowId);
			update.exec();
		}

		row->m_digest = digest;
		row->m_image = QStringLiteral("image://notifimg/") + digest;
		// The group reads its image through the source row and listens to
		// imageChanged, so this emit is enough to keep the card in sync.
		emit row->imageChanged();
	}
}

void NotificationStore::tick() {
	const qint64 now = QDateTime::currentMSecsSinceEpoch();

	for (auto* row : std::as_const(m_rows)) {
		if (m_autoExpire && row->expired(now)) {
			row->setPopup(false);
		}
	}

	if (m_nextTimeStrRefresh <= now) {
		m_nextTimeStrRefresh = now + TIME_STR_REFRESH_MS;

		for (auto* row : std::as_const(m_rows)) {
			row->refreshTimeStr();
		}

		for (auto* group : std::as_const(m_groups)) {
			group->refreshActive();
		}
	}

	if (m_nextPrune <= now) {
		m_nextPrune = now + PRUNE_INTERVAL_MS;
		prune();
		trimRows();
	}
}

} // namespace ZShell::Services