Image provider image caching

src/mxcimageprovider.cpp

 #include "mxcimageprovider.h"
 
 #include <QDebug>
+#include <QDir>
+#include <QFileInfo>
+#include <QStandardPaths>
 
 #include "client.h"
 #include "debug_out.h"
 
 void MXCImageResponse::run() {
-    qDebug() << "Downloading image: " << m_id;
+
+    QFileInfo cacheFile(QStandardPaths::writableLocation(QStandardPaths::CacheLocation) + "/" + m_id);
 
     if (m_requestedSize.isValid()) {
+
+        cacheFile = QFileInfo(cacheFile.filePath() +
+                              QString("_%1x%2").arg(m_requestedSize.width()).arg(m_requestedSize.height()));
+        if (m_image.load(cacheFile.filePath())) {
+            emit finished();
+            qDebug() << "Loaded cached thumbnail: " << m_id;
+            return;
+        }
+
+        qDebug() << "Downloading thumbnail: " << m_id;
+
         mtx::http::ThumbOpts opts;
         opts.mxc_url = "mxc://" + m_id.toStdString();
         opts.width = m_requestedSize.width();
         opts.height = m_requestedSize.height();
         opts.method = "scale";
-        http::client().get_thumbnail(opts, [this](const std::string &res, mtx::http::RequestErr err) {
+        http::client().get_thumbnail(opts, [this, cacheFile](const std::string &res, mtx::http::RequestErr err) {
             if (err) {
                 qDebug() << "Failed to retrieve image: " << m_id << " error: " << *err;
                 m_error = "Failed download";
@@ -26,13 +41,25 @@ void MXCImageResponse::run() {
             auto data = QByteArray(res.data(), res.size());
             m_image.loadFromData(data);
             m_image = m_image.scaled(m_requestedSize, Qt::KeepAspectRatio);
+            m_image.setText("mxc url", "mxc://" + m_id);
+
+            QDir().mkpath(cacheFile.path());
+            m_image.save(cacheFile.filePath(), "png");
 
             emit finished();
         });
     } else {
+        if (m_image.load(cacheFile.filePath())) {
+            emit finished();
+            qDebug() << "Loaded cached image: " << m_id;
+            return;
+        }
+
+        qDebug() << "Downloading image: " << m_id;
+
         http::client().download("mxc://" + m_id.toStdString(),
-                                [this](const std::string &res, const std::string &content_type,
-                                       const std::string &originalFilename, mtx::http::RequestErr err) {
+                                [this, cacheFile](const std::string &res, const std::string &content_type,
+                                                  const std::string &originalFilename, mtx::http::RequestErr err) {
                                     if (err) {
                                         qDebug() << "Failed to retrieve image: " << m_id << " error: " << *err;
                                         m_error = "Failed download";
@@ -43,6 +70,11 @@ void MXCImageResponse::run() {
 
                                     auto data = QByteArray(res.data(), res.size());
                                     m_image.loadFromData(data);
+                                    m_image.setText("original filename", QString::fromStdString(originalFilename));
+                                    m_image.setText("mxc url", "mxc://" + m_id);
+
+                                    QDir().mkpath(cacheFile.path());
+                                    m_image.save(cacheFile.filePath(), "png");
 
                                     emit finished();
                                 });