3 files changed, 569 insertions, 0 deletions
diff --git a/plugin/src/Caelestia/Models/CMakeLists.txt b/plugin/src/Caelestia/Models/CMakeLists.txt
new file mode 100644
index 0000000..640e29e
--- /dev/null
+++ b/plugin/src/Caelestia/Models/CMakeLists.txt
@@ -0,0 +1,8 @@
+qml_module(caelestia-models
+    URI Caelestia.Models
+    SOURCES
+        filesystemmodel.hpp filesystemmodel.cpp
+    LIBRARIES
+        Qt::Gui
+        Qt::Concurrent
+)
diff --git a/plugin/src/Caelestia/Models/filesystemmodel.cpp b/plugin/src/Caelestia/Models/filesystemmodel.cpp
new file mode 100644
index 0000000..54807b5
--- /dev/null
+++ b/plugin/src/Caelestia/Models/filesystemmodel.cpp
@@ -0,0 +1,430 @@
+#include "filesystemmodel.hpp"
+
+#include <qdiriterator.h>
+#include <qfuturewatcher.h>
+#include <qtconcurrentrun.h>
+
+namespace caelestia {
+
+FileSystemEntry::FileSystemEntry(const QString& path, const QString& relativePath, QObject* parent)
+    : QObject(parent)
+    , m_fileInfo(QFileInfo(path))
+    , m_path(path)
+    , m_relativePath(relativePath)
+    , m_isImageInitialised(false)
+    , m_mimeTypeInitialised(false) {}
+
+QString FileSystemEntry::path() const {
+    return m_path;
+};
+
+QString FileSystemEntry::relativePath() const {
+    return m_relativePath;
+};
+
+QString FileSystemEntry::name() const {
+    return m_fileInfo.fileName();
+};
+
+QString FileSystemEntry::parentDir() const {
+    return m_fileInfo.absolutePath();
+};
+
+QString FileSystemEntry::suffix() const {
+    return m_fileInfo.completeSuffix();
+};
+
+qint64 FileSystemEntry::size() const {
+    return m_fileInfo.size();
+};
+
+bool FileSystemEntry::isDir() const {
+    return m_fileInfo.isDir();
+};
+
+bool FileSystemEntry::isImage() const {
+    if (!m_isImageInitialised) {
+        QImageReader reader(m_path);
+        m_isImage = reader.canRead();
+        m_isImageInitialised = true;
+    }
+    return m_isImage;
+}
+
+QString FileSystemEntry::mimeType() const {
+    if (!m_mimeTypeInitialised) {
+        const QMimeDatabase db;
+        m_mimeType = db.mimeTypeForFile(m_path).name();
+        m_mimeTypeInitialised = true;
+    }
+    return m_mimeType;
+}
+
+FileSystemModel::FileSystemModel(QObject* parent)
+    : QAbstractListModel(parent)
+    , m_recursive(false)
+    , m_watchChanges(true)
+    , m_showHidden(false)
+    , m_filter(NoFilter) {
+    connect(&m_watcher, &QFileSystemWatcher::directoryChanged, this, &FileSystemModel::watchDirIfRecursive);
+    connect(&m_watcher, &QFileSystemWatcher::directoryChanged, this, &FileSystemModel::updateEntriesForDir);
+}
+
+int FileSystemModel::rowCount(const QModelIndex& parent) const {
+    if (parent != QModelIndex()) {
+        return 0;
+    }
+    return static_cast<int>(m_entries.size());
+}
+
+QVariant FileSystemModel::data(const QModelIndex& index, int role) const {
+    if (role != Qt::UserRole || !index.isValid() || index.row() >= m_entries.size()) {
+        return QVariant();
+    }
+    return QVariant::fromValue(m_entries.at(index.row()));
+}
+
+QHash<int, QByteArray> FileSystemModel::roleNames() const {
+    return { { Qt::UserRole, "modelData" } };
+}
+
+QString FileSystemModel::path() const {
+    return m_path;
+}
+
+void FileSystemModel::setPath(const QString& path) {
+    if (m_path == path) {
+        return;
+    }
+
+    m_path = path;
+    emit pathChanged();
+
+    m_dir.setPath(m_path);
+    update();
+}
+
+bool FileSystemModel::recursive() const {
+    return m_recursive;
+}
+
+void FileSystemModel::setRecursive(bool recursive) {
+    if (m_recursive == recursive) {
+        return;
+    }
+
+    m_recursive = recursive;
+    emit recursiveChanged();
+
+    update();
+}
+
+bool FileSystemModel::watchChanges() const {
+    return m_watchChanges;
+}
+
+void FileSystemModel::setWatchChanges(bool watchChanges) {
+    if (m_watchChanges == watchChanges) {
+        return;
+    }
+
+    m_watchChanges = watchChanges;
+    emit watchChangesChanged();
+
+    update();
+}
+
+bool FileSystemModel::showHidden() const {
+    return m_showHidden;
+}
+
+void FileSystemModel::setShowHidden(bool showHidden) {
+    if (m_showHidden == showHidden) {
+        return;
+    }
+
+    m_showHidden = showHidden;
+    emit showHiddenChanged();
+
+    update();
+}
+
+FileSystemModel::Filter FileSystemModel::filter() const {
+    return m_filter;
+}
+
+void FileSystemModel::setFilter(Filter filter) {
+    if (m_filter == filter) {
+        return;
+    }
+
+    m_filter = filter;
+    emit filterChanged();
+
+    update();
+}
+
+QList<FileSystemEntry*> FileSystemModel::entries() const {
+    return m_entries;
+}
+
+void FileSystemModel::watchDirIfRecursive(const QString& path) {
+    if (m_recursive && m_watchChanges) {
+        const auto currentDir = m_dir;
+        const bool showHidden = m_showHidden;
+        const auto future = QtConcurrent::run([showHidden, path]() {
+            QDir::Filters filters = QDir::Dirs | QDir::NoDotAndDotDot;
+            if (showHidden) {
+                filters |= QDir::Hidden;
+            }
+
+            QDirIterator iter(path, filters, QDirIterator::Subdirectories);
+            QStringList dirs;
+            while (iter.hasNext()) {
+                dirs << iter.next();
+            }
+            return dirs;
+        });
+        const auto watcher = new QFutureWatcher<QStringList>(this);
+        connect(watcher, &QFutureWatcher<QStringList>::finished, this, [currentDir, showHidden, watcher, this]() {
+            const auto paths = watcher->result();
+            if (currentDir == m_dir && showHidden == m_showHidden && !paths.isEmpty()) {
+                // Ignore if dir or showHidden has changed
+                m_watcher.addPaths(paths);
+            }
+            watcher->deleteLater();
+        });
+        watcher->setFuture(future);
+    }
+}
+
+void FileSystemModel::update() {
+    updateWatcher();
+    updateEntries();
+}
+
+void FileSystemModel::updateWatcher() {
+    if (!m_watcher.directories().isEmpty()) {
+        m_watcher.removePaths(m_watcher.directories());
+    }
+
+    if (!m_watchChanges || m_path.isEmpty()) {
+        return;
+    }
+
+    m_watcher.addPath(m_path);
+    watchDirIfRecursive(m_path);
+}
+
+void FileSystemModel::updateEntries() {
+    if (m_path.isEmpty()) {
+        if (!m_entries.isEmpty()) {
+            beginResetModel();
+            qDeleteAll(m_entries);
+            m_entries.clear();
+            emit entriesChanged();
+            endResetModel();
+        }
+
+        return;
+    }
+
+    for (auto& future : m_futures) {
+        future.cancel();
+    }
+    m_futures.clear();
+
+    updateEntriesForDir(m_path);
+}
+
+void FileSystemModel::updateEntriesForDir(const QString& dir) {
+    const bool recursive = m_recursive;
+    const bool showHidden = m_showHidden;
+    const auto filter = m_filter;
+    const auto oldEntries = m_entries;
+    const auto baseDir = m_dir;
+
+    const auto future = QtConcurrent::run([dir, recursive, showHidden, filter, oldEntries, baseDir](
+                                              QPromise<QPair<QSet<QString>, QSet<QString>>>& promise) {
+        const auto flags = recursive ? QDirIterator::Subdirectories : QDirIterator::NoIteratorFlags;
+
+        std::optional<QDirIterator> iter;
+
+        if (filter == Images) {
+            QStringList nameFilters;
+            for (const auto& format : QImageReader::supportedImageFormats()) {
+                nameFilters << "*." + format;
+            }
+
+            QDir::Filters filters = QDir::Files;
+            if (showHidden) {
+                filters |= QDir::Hidden;
+            }
+
+            iter.emplace(dir, nameFilters, filters, flags);
+        } else {
+            QDir::Filters filters;
+
+            if (filter == Files) {
+                filters = QDir::Files;
+            } else if (filter == Dirs) {
+                filters = QDir::Dirs | QDir::NoDotAndDotDot;
+            } else {
+                filters = QDir::Dirs | QDir::Files | QDir::NoDotAndDotDot;
+            }
+
+            if (showHidden) {
+                filters |= QDir::Hidden;
+            }
+
+            iter.emplace(dir, filters, flags);
+        }
+
+        QSet<QString> newPaths;
+        while (iter->hasNext()) {
+            if (promise.isCanceled()) {
+                return;
+            }
+
+            QString path = iter->next();
+
+            if (filter == Images) {
+                QImageReader reader(path);
+                if (!reader.canRead()) {
+                    continue;
+                }
+            }
+
+            newPaths.insert(path);
+        }
+
+        QSet<QString> oldPaths;
+        for (const auto& entry : oldEntries) {
+            oldPaths.insert(entry->path());
+        }
+
+        if (promise.isCanceled() || newPaths == oldPaths) {
+            return;
+        }
+
+        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, [dir, watcher, this]() {
+        m_futures.remove(dir);
+
+        if (!watcher->future().isResultReadyAt(0)) {
+            watcher->deleteLater();
+            return;
+        }
+
+        const auto result = watcher->result();
+        applyChanges(result.first, result.second);
+
+        watcher->deleteLater();
+    });
+
+    watcher->setFuture(future);
+}
+
+void FileSystemModel::applyChanges(const QSet<QString>& removedPaths, const QSet<QString>& addedPaths) {
+    QList<int> removedIndices;
+    for (int i = 0; i < m_entries.size(); ++i) {
+        if (removedPaths.contains(m_entries[i]->path())) {
+            removedIndices << i;
+        }
+    }
+    std::sort(removedIndices.begin(), removedIndices.end(), std::greater<int>());
+
+    int start = -1;
+    int end = -1;
+    for (int idx : removedIndices) {
+        if (start == -1) {
+            start = idx;
+            end = idx;
+        } else if (idx == end - 1) {
+            end = idx;
+        } else {
+            beginRemoveRows(QModelIndex(), end, start);
+            for (int i = start; i >= end; --i) {
+                emit removed(m_entries[i]->path());
+                delete m_entries.takeAt(i);
+            }
+            endRemoveRows();
+
+            start = idx;
+            end = idx;
+        }
+    }
+    if (start != -1) {
+        beginRemoveRows(QModelIndex(), end, start);
+        for (int i = start; i >= end; --i) {
+            emit removed(m_entries[i]->path());
+            delete m_entries.takeAt(i);
+        }
+        endRemoveRows();
+    }
+
+    QList<FileSystemEntry*> newEntries;
+    for (const auto& path : addedPaths) {
+        newEntries << new FileSystemEntry(path, m_dir.relativeFilePath(path), this);
+    }
+    std::sort(newEntries.begin(), newEntries.end(), &FileSystemModel::compareEntries);
+
+    int insertStart = -1;
+    int prevRow = -1;
+    QList<FileSystemEntry*> batchItems;
+    for (const auto& entry : newEntries) {
+        const auto it = std::lower_bound(m_entries.begin(), m_entries.end(), entry, &FileSystemModel::compareEntries);
+        int row = static_cast<int>(it - m_entries.begin());
+
+        if (insertStart == -1) {
+            insertStart = row;
+            prevRow = row;
+            batchItems.clear();
+            batchItems << entry;
+        } else if (row == prevRow + 1) {
+            prevRow = row;
+            batchItems << entry;
+        } else {
+            beginInsertRows(QModelIndex(), insertStart, static_cast<int>(insertStart + batchItems.size() - 1));
+            for (int i = 0; i < batchItems.size(); ++i) {
+                m_entries.insert(insertStart + i, batchItems[i]);
+                emit added(batchItems[i]);
+            }
+            endInsertRows();
+
+            insertStart = row;
+            prevRow = row;
+            batchItems.clear();
+            batchItems << entry;
+        }
+        prevRow = static_cast<int>(m_entries.indexOf(entry));
+    }
+    if (!batchItems.isEmpty()) {
+        beginInsertRows(QModelIndex(), insertStart, static_cast<int>(insertStart + batchItems.size() - 1));
+        for (int i = 0; i < batchItems.size(); ++i) {
+            m_entries.insert(insertStart + i, batchItems[i]);
+            emit added(batchItems[i]);
+        }
+        endInsertRows();
+    }
+
+    emit entriesChanged();
+}
+
+bool FileSystemModel::compareEntries(const FileSystemEntry* a, const FileSystemEntry* b) {
+    if (a->isDir() != b->isDir()) {
+        return a->isDir();
+    }
+    return a->relativePath().localeAwareCompare(b->relativePath()) < 0;
+}
+
+} // namespace caelestia
diff --git a/plugin/src/Caelestia/Models/filesystemmodel.hpp b/plugin/src/Caelestia/Models/filesystemmodel.hpp
new file mode 100644
index 0000000..4ea5f0a
--- /dev/null
+++ b/plugin/src/Caelestia/Models/filesystemmodel.hpp
@@ -0,0 +1,131 @@
+#pragma once
+
+#include <qabstractitemmodel.h>
+#include <qdir.h>
+#include <qfilesystemwatcher.h>
+#include <qfuture.h>
+#include <qimagereader.h>
+#include <qmimedatabase.h>
+#include <qobject.h>
+#include <qqmlintegration.h>
+
+namespace caelestia {
+
+class FileSystemEntry : public QObject {
+    Q_OBJECT
+    QML_ELEMENT
+    QML_UNCREATABLE("FileSystemEntry instances can only be retrieved from a FileSystemModel")
+
+    Q_PROPERTY(QString path READ path CONSTANT)
+    Q_PROPERTY(QString relativePath READ relativePath CONSTANT)
+    Q_PROPERTY(QString name READ name CONSTANT)
+    Q_PROPERTY(QString parentDir READ parentDir CONSTANT)
+    Q_PROPERTY(QString suffix READ suffix CONSTANT)
+    Q_PROPERTY(qint64 size READ size CONSTANT)
+    Q_PROPERTY(bool isDir READ isDir CONSTANT)
+    Q_PROPERTY(bool isImage READ isImage CONSTANT)
+    Q_PROPERTY(QString mimeType READ mimeType CONSTANT)
+
+public:
+    explicit FileSystemEntry(const QString& path, const QString& relativePath, QObject* parent = nullptr);
+
+    [[nodiscard]] QString path() const;
+    [[nodiscard]] QString relativePath() const;
+    [[nodiscard]] QString name() const;
+    [[nodiscard]] QString parentDir() const;
+    [[nodiscard]] QString suffix() const;
+    [[nodiscard]] qint64 size() const;
+    [[nodiscard]] bool isDir() const;
+    [[nodiscard]] bool isImage() const;
+    [[nodiscard]] QString mimeType() const;
+
+private:
+    const QFileInfo m_fileInfo;
+
+    const QString m_path;
+    const QString m_relativePath;
+
+    mutable bool m_isImage;
+    mutable bool m_isImageInitialised;
+
+    mutable QString m_mimeType;
+    mutable bool m_mimeTypeInitialised;
+};
+
+class FileSystemModel : public QAbstractListModel {
+    Q_OBJECT
+    QML_ELEMENT
+
+    Q_PROPERTY(QString path READ path WRITE setPath NOTIFY pathChanged)
+    Q_PROPERTY(bool recursive READ recursive WRITE setRecursive NOTIFY recursiveChanged)
+    Q_PROPERTY(bool watchChanges READ watchChanges WRITE setWatchChanges NOTIFY watchChangesChanged)
+    Q_PROPERTY(bool showHidden READ showHidden WRITE setShowHidden NOTIFY showHiddenChanged)
+    Q_PROPERTY(Filter filter READ filter WRITE setFilter NOTIFY filterChanged)
+
+    Q_PROPERTY(QList<FileSystemEntry*> entries READ entries NOTIFY entriesChanged)
+
+public:
+    enum Filter {
+        NoFilter,
+        Images,
+        Files,
+        Dirs
+    };
+    Q_ENUM(Filter)
+
+    explicit FileSystemModel(QObject* parent = nullptr);
+
+    int rowCount(const QModelIndex& parent = QModelIndex()) const override;
+    QVariant data(const QModelIndex& index, int role = Qt::DisplayRole) const override;
+    QHash<int, QByteArray> roleNames() const override;
+
+    [[nodiscard]] QString path() const;
+    void setPath(const QString& path);
+
+    [[nodiscard]] bool recursive() const;
+    void setRecursive(bool recursive);
+
+    [[nodiscard]] bool watchChanges() const;
+    void setWatchChanges(bool watchChanges);
+
+    [[nodiscard]] bool showHidden() const;
+    void setShowHidden(bool showHidden);
+
+    [[nodiscard]] Filter filter() const;
+    void setFilter(Filter filter);
+
+    [[nodiscard]] QList<FileSystemEntry*> entries() const;
+
+signals:
+    void pathChanged();
+    void recursiveChanged();
+    void watchChangesChanged();
+    void showHiddenChanged();
+    void filterChanged();
+    void entriesChanged();
+
+    void added(const FileSystemEntry* entry);
+    void removed(const QString& path);
+
+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;
+    bool m_watchChanges;
+    bool m_showHidden;
+    Filter m_filter;
+
+    void watchDirIfRecursive(const QString& path);
+    void update();
+    void updateWatcher();
+    void updateEntries();
+    void updateEntriesForDir(const QString& dir);
+    void applyChanges(const QSet<QString>& removedPaths, const QSet<QString>& addedPaths);
+    [[nodiscard]] static bool compareEntries(const FileSystemEntry* a, const FileSystemEntry* b);
+};
+
+} // namespace caelestia