plugin/fsm: async update

plugin/CMakeLists.txt

@@ -1,4 +1,4 @@
-find_package(Qt6 REQUIRED COMPONENTS Core Qml Gui)
+find_package(Qt6 REQUIRED COMPONENTS Core Qml Gui Concurrent)
 
 if(QT_KNOWN_POLICY_QTP0001)
     qt_policy(SET QTP0001 NEW)

plugin/src/Caelestia/CMakeLists.txt

@@ -24,4 +24,4 @@ install(TARGETS "${module_plugin_target}" LIBRARY DESTINATION "${module_dir}" RU
 install(FILES "${module_qmldir}" DESTINATION "${module_dir}")
 install(FILES "${module_typeinfo}" DESTINATION "${module_dir}")
 
-target_link_libraries(caelestia PRIVATE Qt::Core Qt::Qml Qt::Gui)
+target_link_libraries(caelestia PRIVATE Qt::Core Qt::Qml Qt::Gui Qt::Concurrent)

plugin/src/Caelestia/filesystemmodel.cpp

@@ -4,8 +4,10 @@
 #include <QDir>
 #include <QDirIterator>
 #include <QFileInfo>
+#include <QFutureWatcher>
 #include <QImageReader>
 #include <QObject>
+#include <QtConcurrent>
 #include <qqmlintegration.h>
 
 int FileSystemModel::rowCount(const QModelIndex& parent) const {
@@ -116,22 +118,34 @@ void FileSystemModel::updateEntries() {
         return;
     }
 
+    for (auto& future : m_futures) {
+        future.cancel();
+    }
+    m_futures.clear();
+
     updateEntriesForDir(m_path);
 }
 
 void FileSystemModel::updateEntriesForDir(const QString& dir) {
-    const auto flags = m_recursive ? QDirIterator::Subdirectories : QDirIterator::NoIteratorFlags;
+    const bool recursive = m_recursive;
+    const auto filter = m_filter;
+    const auto oldEntries = m_entries;
+    const auto baseDir = m_dir;
+
+    const auto future = QtConcurrent::run(
+        [dir, recursive, filter, oldEntries, baseDir](QPromise<QPair<QSet<QString>, QSet<QString>>>& promise) {
+            const auto flags = recursive ? QDirIterator::Subdirectories : QDirIterator::NoIteratorFlags;
 
             std::optional<QDirIterator> iter;
 
-    if (m_filter == Images) {
+            if (filter == Images) {
                 QStringList filters;
                 for (const auto& format : QImageReader::supportedImageFormats()) {
                     filters << "*." + format;
                 }
 
                 iter.emplace(dir, filters, QDir::Files, flags);
-    } else if (m_filter == Files) {
+            } else if (filter == Files) {
                 iter.emplace(dir, QDir::Files, flags);
             } else {
                 iter.emplace(dir, QDir::Dirs | QDir::Files | QDir::NoDotAndDotDot, flags);
@@ -139,9 +153,13 @@ void FileSystemModel::updateEntriesForDir(const QString& dir) {
 
             QSet<QString> newPaths;
             while (iter->hasNext()) {
+                if (promise.isCanceled()) {
+                    return;
+                }
+
                 QString path = iter->next();
 
-        if (m_filter == Images) {
+                if (filter == Images) {
                     QImageReader reader(path);
                     if (!reader.canRead()) {
                         continue;
@@ -152,16 +170,36 @@ void FileSystemModel::updateEntriesForDir(const QString& dir) {
             }
 
             QSet<QString> oldPaths;
-    for (const auto& entry : m_entries) {
+            for (const auto& entry : oldEntries) {
                 oldPaths.insert(entry->path());
             }
 
-    if (newPaths == oldPaths) {
+            if (promise.isCanceled() || newPaths == oldPaths) {
                 return;
             }
 
-    const QSet<QString> removedPaths = oldPaths - newPaths;
-    const QSet<QString> addedPaths = newPaths - oldPaths;
+            promise.addResult(qMakePair(oldPaths - newPaths, newPaths - oldPaths));
+        });
+
+    if (m_futures.contains(dir)) {
+        m_futures[dir].cancel();
+    }
+    m_futures.insert(dir, future);
+
+    const auto watcher = new QFutureWatcher<QPair<QSet<QString>, QSet<QString>>>(this);
+
+    connect(watcher, &QFutureWatcher<QPair<QSet<QString>, QSet<QString>>>::finished, this, [watcher, this]() {
+        if (!watcher->future().isResultReadyAt(0)) {
+            watcher->deleteLater();
+            return;
+        }
+
+        QElapsedTimer timer;
+        timer.start();
+
+        const auto result = watcher->result();
+        const auto removedPaths = result.first;
+        const auto addedPaths = result.second;
 
         beginResetModel();
 
@@ -189,4 +227,11 @@ void FileSystemModel::updateEntriesForDir(const QString& dir) {
         emit entriesChanged();
 
         endResetModel();
+
+        watcher->deleteLater();
+
+        qDebug() << "Update took" << timer.elapsed() << "ms";
+    });
+
+    watcher->setFuture(future);
 }

plugin/src/Caelestia/filesystemmodel.hpp

@@ -4,6 +4,7 @@
 #include <QDir>
 #include <QFileInfo>
 #include <QFileSystemWatcher>
+#include <QFuture>
 #include <QImageReader>
 #include <QObject>
 #include <qqmlintegration.h>
@@ -109,6 +110,7 @@ private:
     QDir m_dir;
     QFileSystemWatcher m_watcher;
     QList<FileSystemEntry*> m_entries;
+    QHash<QString, QFuture<QPair<QSet<QString>, QSet<QString>>>> m_futures;
 
     QString m_path;
     bool m_recursive;