plugin: create caching image manager

No need for external proc

4 files changed, 182 insertions, 1 deletions

diff --git a/plugin/src/Caelestia/CMakeLists.txt b/plugin/src/Caelestia/CMakeLists.txt
index 61d7f7e..3ea0225 100644
--- a/plugin/src/Caelestia/CMakeLists.txt
+++ b/plugin/src/Caelestia/CMakeLists.txt
@@ -3,6 +3,7 @@ qt_add_qml_module(caelestia
     VERSION 0.1
     SOURCES
         cutils.hpp cutils.cpp
+        cachingimagemanager.hpp cachingimagemanager.cpp
 )
 
 qt_query_qml_module(caelestia
diff --git a/plugin/src/Caelestia/cachingimagemanager.cpp b/plugin/src/Caelestia/cachingimagemanager.cpp
new file mode 100644
index 0000000..d557203
--- /dev/null
+++ b/plugin/src/Caelestia/cachingimagemanager.cpp
@@ -0,0 +1,122 @@
+#include "cachingimagemanager.hpp"
+
+#include <qobject.h>
+#include <QtQuick/QQuickItem>
+#include <QtQuick/QQuickWindow>
+#include <QCryptographicHash>
+#include <QThreadPool>
+#include <QFile>
+
+qreal CachingImageManager::effectiveScale() const {
+    if (m_item->window() && m_item->window()->screen()) {
+        return m_item->window()->screen()->devicePixelRatio();
+    }
+
+    return 1.0;
+}
+
+int CachingImageManager::effectiveWidth() const {
+    int width = std::ceil(m_item->width() * effectiveScale());
+    m_item->setProperty("sourceWidth", width);
+    return width;
+}
+
+int CachingImageManager::effectiveHeight() const {
+    int height = std::ceil(m_item->height() * effectiveScale());
+    m_item->setProperty("sourceHeight", height);
+    return height;
+}
+
+QQuickItem* CachingImageManager::item() const {
+    return m_item;
+}
+
+void CachingImageManager::setItem(QQuickItem* item) {
+    if (m_item == item) {
+        return;
+    }
+
+    m_item = item;
+    emit itemChanged();
+}
+
+QUrl CachingImageManager::cacheDir() const {
+    return m_cacheDir;
+}
+
+void CachingImageManager::setCacheDir(const QUrl& cacheDir) {
+    if (m_cacheDir == cacheDir) {
+        return;
+    }
+
+    m_cacheDir = cacheDir;
+    emit cacheDirChanged();
+}
+
+QString CachingImageManager::path() const {
+    return m_path;
+}
+
+void CachingImageManager::setPath(const QString& path) {
+    if (m_path == path) {
+        return;
+    }
+
+    m_path = path;
+    emit pathChanged();
+
+    if (!path.isEmpty()) {
+        QThreadPool::globalInstance()->start([path, this] {
+            const QString filename = QString("%1@%2x%3.png")
+                .arg(sha256sum(path))
+                .arg(effectiveWidth())
+                .arg(effectiveHeight());
+
+            m_cachePath = m_cacheDir.resolved(QUrl(filename));
+            emit cachePathChanged();
+
+            if (!m_cachePath.isLocalFile()) {
+                qWarning() << "CachingImageManager::setPath: cachePath" << m_cachePath << "is not a local file";
+                return;
+            }
+
+            if (QFile::exists(m_cachePath.toLocalFile())) {
+                QMetaObject::invokeMethod(m_item, [this]() {
+                    m_item->setProperty("source", m_cachePath);
+                }, Qt::QueuedConnection);
+
+                m_usingCache = true;
+                emit usingCacheChanged();
+            } else {
+                QMetaObject::invokeMethod(m_item, [path, this]() {
+                    m_item->setProperty("source", QUrl::fromLocalFile(path));
+                }, Qt::QueuedConnection);
+
+                m_usingCache = false;
+                emit usingCacheChanged();
+            }
+        });
+    }
+}
+
+QUrl CachingImageManager::cachePath() const {
+    return m_cachePath;
+}
+
+bool CachingImageManager::usingCache() const {
+    return m_usingCache;
+}
+
+QString CachingImageManager::sha256sum(const QString& path) const {
+    QFile file(path);
+    if (!file.open(QIODevice::ReadOnly)) {
+        qWarning() << "CachingImageManager::sha256sum: failed to open" << path;
+        return "";
+    }
+
+    QCryptographicHash hash(QCryptographicHash::Sha256);
+    hash.addData(&file);
+    file.close();
+
+    return hash.result().toHex();
+}
diff --git a/plugin/src/Caelestia/cachingimagemanager.hpp b/plugin/src/Caelestia/cachingimagemanager.hpp
new file mode 100644
index 0000000..e2cbd41
--- /dev/null
+++ b/plugin/src/Caelestia/cachingimagemanager.hpp
@@ -0,0 +1,57 @@
+#pragma once
+
+#include <qobject.h>
+#include <qqmlintegration.h>
+#include <QtQuick/QQuickItem>
+
+class CachingImageManager : public QObject {
+    Q_OBJECT;
+    QML_ELEMENT;
+
+    Q_PROPERTY(QQuickItem* item READ item WRITE setItem NOTIFY itemChanged REQUIRED);
+    Q_PROPERTY(QUrl cacheDir READ cacheDir WRITE setCacheDir NOTIFY cacheDirChanged REQUIRED);
+
+    Q_PROPERTY(QString path READ path WRITE setPath NOTIFY pathChanged);
+    Q_PROPERTY(QUrl cachePath READ cachePath NOTIFY cachePathChanged);
+    Q_PROPERTY(bool usingCache READ usingCache NOTIFY usingCacheChanged);
+
+public:
+    explicit CachingImageManager(QObject* parent = nullptr): QObject(parent) {};
+
+    [[nodiscard]] QQuickItem* item() const;
+    void setItem(QQuickItem* item);
+
+    [[nodiscard]] QUrl cacheDir() const;
+    void setCacheDir(const QUrl& cacheDir);
+
+    [[nodiscard]] QString path() const;
+    void setPath(const QString& path);
+
+    [[nodiscard]] QUrl cachePath() const;
+    [[nodiscard]] bool usingCache() const;
+
+signals:
+    void itemChanged();
+    void cacheDirChanged();
+
+    void pathChanged();
+    void cachePathChanged();
+    void usingCacheChanged();
+
+private slots:
+    void handleStatusChanged();
+
+private:
+    QQuickItem* m_item;
+    QUrl m_cacheDir;
+
+    QString m_path;
+    QUrl m_cachePath;
+    bool m_usingCache;
+
+    [[nodiscard]] qreal effectiveScale() const;
+    int effectiveWidth() const;
+    int effectiveHeight() const;
+
+    [[nodiscard]] QString sha256sum(const QString& path) const;
+};
diff --git a/plugin/src/Caelestia/cutils.hpp b/plugin/src/Caelestia/cutils.hpp
index e1319a4..76beb2b 100644
--- a/plugin/src/Caelestia/cutils.hpp
+++ b/plugin/src/Caelestia/cutils.hpp
@@ -1,11 +1,12 @@
 #pragma once
 
 #include <qobject.h>
+#include <qqmlintegration.h>
 #include <QtQuick/QQuickItem>
 
 class CUtils : public QObject {
     Q_OBJECT;
-    QML_NAMED_ELEMENT(CUtils);
+    QML_ELEMENT;
     QML_SINGLETON;
 
 public: