Working on snapshot save/loading

utils/fgqcanvas/fgqcanvasfontcache.cpp

@@ -137,8 +137,8 @@ void FGQCanvasFontCache::lookupFile(QByteArray name)
     reply->setProperty("font", name);
 
     connect(reply, &QNetworkReply::finished, this, &FGQCanvasFontCache::onFontDownloadFinished);
-    // connect(reply, &QNetworkReply::error, this, &FGQCanvasFontCache::onFontDownloadError);
-
+    connect(reply, SIGNAL(error(QNetworkReply::NetworkError)),
+            this, SLOT(onFontDownloadError(QNetworkReply::NetworkError)));
     m_transfers.append(reply);
 }
 

utils/fgqcanvas/fgqcanvasimageloader.cpp

@@ -19,6 +19,10 @@
 
 #include <QDebug>
 #include <QNetworkAccessManager>
+#include <QStandardPaths>
+#include <QDir>
+#include <QFile>
+#include <QFileInfo>
 
 class TransferSignalHolder : public QObject
 {
@@ -43,8 +47,11 @@ void FGQCanvasImageLoader::onDownloadFinished()
     if (!pm.loadFromData(reply->readAll())) {
         qWarning() << "image loading failed";
     } else {
-        qDebug() << "did download:" << reply->property("image").toByteArray();
-        m_cache.insert(reply->property("image").toByteArray(), pm);
+        QByteArray imagePath = reply->property("image").toByteArray();
+        m_cache.insert(imagePath, pm);
+
+        // cache on disk also, so snapshots work
+        writeToDiskCache(imagePath, reply);
 
         TransferSignalHolder* signalHolder = reply->findChild<TransferSignalHolder*>("holder");
         if (signalHolder) {
@@ -57,6 +64,23 @@ void FGQCanvasImageLoader::onDownloadFinished()
     reply->deleteLater();
 }
 
+void FGQCanvasImageLoader::writeToDiskCache(QByteArray imagePath, QNetworkReply* reply)
+{
+    QDir cacheDir(QStandardPaths::writableLocation(QStandardPaths::CacheLocation));
+    QString absPath = cacheDir.absoluteFilePath(imagePath);
+
+    QFileInfo finfo(imagePath);
+    cacheDir.mkpath(finfo.dir().path());
+
+    QFile f(absPath);
+    if (!f.open(QIODevice::WriteOnly)) {
+        qWarning() << "failed to open cache file" << f.fileName();
+    }
+
+    f.write(reply->readAll());
+    f.close();
+}
+
 void FGQCanvasImageLoader::setHost(QString hostName, int portNumber)
 {
     m_hostName = hostName;
@@ -70,6 +94,15 @@ QPixmap FGQCanvasImageLoader::getImage(const QByteArray &imagePath)
         return m_cache.value(imagePath);
     }
 
+    QString diskCachePath = QStandardPaths::locate(QStandardPaths::CacheLocation, imagePath);
+    if (!diskCachePath.isEmpty()) {
+        QPixmap pix;
+        pix.load(diskCachePath);
+        m_cache.insert(imagePath, pix);
+        qDebug() << "loaded from on-disk cache:" << imagePath;
+        return pix;
+    }
+
     QUrl url;
     url.setScheme("http");
     url.setHost(m_hostName);
@@ -82,7 +115,6 @@ QPixmap FGQCanvasImageLoader::getImage(const QByteArray &imagePath)
         }
     }
 
-    qDebug() << "requesting image" << url;
     QNetworkReply* reply = m_downloader->get(QNetworkRequest(url));
     reply->setProperty("image", imagePath);
 

utils/fgqcanvas/fgqcanvasimageloader.h

@@ -50,6 +50,7 @@ signals:
 private:
 
     void onDownloadFinished();
+    void writeToDiskCache(QByteArray imagePath, QNetworkReply *reply);
 
 private:
     QNetworkAccessManager* m_downloader;

utils/fgqcanvas/localprop.cpp

@@ -20,6 +20,18 @@
 #include <QJsonValue>
 #include <QDebug>
 
+QDataStream& operator<<(QDataStream& stream, const NameIndexTuple& nameIndex)
+{
+    stream << nameIndex.name << nameIndex.index;
+    return stream;
+}
+
+QDataStream& operator>>(QDataStream& stream, NameIndexTuple& nameIndex)
+{
+    stream >> nameIndex.name >> nameIndex.index;
+    return stream;
+}
+
 LocalProp *LocalProp::getOrCreateWithPath(const QByteArray &path)
 {
     if (path.isEmpty()) {
@@ -119,6 +131,41 @@ void LocalProp::changeValue(const char *path, QVariant value)
     p->valueChanged(value);
 }
 
+void LocalProp::saveToStream(QDataStream &stream) const
+{
+    stream << _id << _position << _value;
+    stream << static_cast<int>(_children.size());
+    for (auto child : _children) {
+        child->saveToStream(stream);
+    }
+}
+
+LocalProp* LocalProp::restoreFromStream(QDataStream &stream, LocalProp* parent)
+{
+    NameIndexTuple id;
+    stream >> id;
+    LocalProp* prop = new LocalProp(parent, id);
+    stream >> prop->_position >> prop->_value;
+    int childCount;
+    stream >> childCount;
+    for (int c=0; c< childCount; ++c) {
+        prop->_children.push_back(restoreFromStream(stream, prop));
+    }
+
+    return prop;
+}
+
+void LocalProp::recursiveNotifyRestored()
+{
+    emit valueChanged(_value);
+    for (auto child : _children) {
+        emit childAdded(child);
+    }
+
+    for (auto child : _children) {
+        child->recursiveNotifyRestored();
+    }
+}
 
 LocalProp *LocalProp::getOrCreateChildWithNameAndIndex(const NameIndexTuple& ni)
 {

utils/fgqcanvas/localprop.h

@@ -22,12 +22,16 @@
 #include <QVariant>
 #include <QVector>
 #include <QObject>
+#include <QDataStream>
 
 struct NameIndexTuple
 {
     QByteArray name;
     unsigned int index = 0;
 
+    NameIndexTuple()
+    {}
+
     NameIndexTuple(const char* nm, unsigned int idx) :
         name(nm),
         index(idx)
@@ -66,8 +70,12 @@ struct NameIndexTuple
 
         return name < other.name;
     }
+
 };
 
+QDataStream& operator<<(QDataStream& stream, const NameIndexTuple& nameIndex);
+QDataStream& operator>>(QDataStream& stream, NameIndexTuple& nameIndex);
+
 class LocalProp : public QObject
 {
     Q_OBJECT
@@ -126,6 +134,12 @@ public:
     bool hasChild(const char* name) const;
 
     void changeValue(const char* path, QVariant value);
+
+    void saveToStream(QDataStream& stream) const;
+
+    static LocalProp* restoreFromStream(QDataStream& stream, LocalProp *parent);
+
+    void recursiveNotifyRestored();
 signals:
     void valueChanged(QVariant val);
 

utils/fgqcanvas/temporarywidget.cpp

@@ -27,6 +27,9 @@
 #include <QNetworkRequest>
 #include <QNetworkAccessManager>
 #include <QNetworkReply>
+#include <QQuickItem>
+#include <QAction>
+#include <QFileDialog>
 
 #include "fgqcanvasfontcache.h"
 #include "fgqcanvasimageloader.h"
@@ -49,6 +52,16 @@ TemporaryWidget::TemporaryWidget(QWidget *parent) :
     connect(ui->canvasSelectCombo, SIGNAL(activated(int)),
             this, SLOT(onCanvasSelected(int)));
     ui->canvasSelectCombo->hide();
+
+    QAction* saveTreeAction = new QAction("Save", this);
+    saveTreeAction->setShortcut(Qt::CTRL | Qt::Key_S);
+    connect(saveTreeAction, &QAction::triggered, this, &TemporaryWidget::onSave);
+    addAction(saveTreeAction);
+
+    QAction* openSnapshotAction = new QAction("Open snapshot", this);
+    openSnapshotAction->setShortcut(Qt::CTRL | Qt::Key_O);
+    connect(openSnapshotAction, &QAction::triggered, this, &TemporaryWidget::onLoadSnapshot);
+    addAction(openSnapshotAction);
 }
 
 TemporaryWidget::~TemporaryWidget()
@@ -117,13 +130,59 @@ void TemporaryWidget::onFinishedGetCanvasList()
     }
 }
 
-void TemporaryWidget::onWebSocketConnected()
+void TemporaryWidget::onSave()
 {
-    connect(&m_webSocket, &QWebSocket::textMessageReceived,
-            this, &TemporaryWidget::onTextMessageReceived);
+    qDebug() << "should save";
+    if (!m_localPropertyRoot) {
+        return;
+    }
 
-    m_localPropertyRoot = new LocalProp(nullptr, NameIndexTuple(""));
+    QString path = QFileDialog::getSaveFileName(this, tr("Choose name to save"));
+    if (path.isEmpty()) {
+        return;
+    }
 
+    QFile f(path);
+    f.open(QIODevice::ReadWrite);
+
+    {
+        QDataStream ds(&f);
+        m_localPropertyRoot->saveToStream(ds);
+    }
+
+    f.close();
+}
+
+void TemporaryWidget::onLoadSnapshot()
+{
+    qDebug() << "should load";
+
+    QString path = QFileDialog::getOpenFileName(this, tr("Select a saved snapshot"));
+    if (path.isEmpty()) {
+        return;
+    }
+
+    QFile f(path);
+    f.open(QIODevice::ReadOnly);
+
+    {
+        QDataStream ds(&f);
+        m_localPropertyRoot = LocalProp::restoreFromStream(ds, nullptr);
+
+        createdRootProperty();
+
+        m_localPropertyRoot->recursiveNotifyRestored();
+
+        // this is needed for either QtQuick or QPainter drawing
+        ui->canvas->rootElement()->update();
+
+        // this is the widget re-draw request (QtQuick draws all the time)
+        ui->canvas->update();
+    }
+}
+
+void TemporaryWidget::createdRootProperty()
+{
     ui->canvas->setRootProperty(m_localPropertyRoot);
     ui->stack->setCurrentIndex(1);
 
@@ -136,6 +195,16 @@ void TemporaryWidget::onWebSocketConnected()
     ui->elementData->setModel(m_elementModel);
 
     connect(ui->treeView->selectionModel(), &QItemSelectionModel::currentChanged, this, &TemporaryWidget::onTreeCurrentChanged);
+}
+
+void TemporaryWidget::onWebSocketConnected()
+{
+    connect(&m_webSocket, &QWebSocket::textMessageReceived,
+            this, &TemporaryWidget::onTextMessageReceived);
+
+    m_localPropertyRoot = new LocalProp(nullptr, NameIndexTuple(""));
+
+    createdRootProperty();
 
     FGQCanvasFontCache::instance()->setHost(ui->hostName->text(),
                                             ui->portEdit->text().toInt());

utils/fgqcanvas/temporarywidget.h

@@ -52,12 +52,17 @@ private Q_SLOTS:
     void onCanvasSelected(int index);
 
     void onFinishedGetCanvasList();
+
+    void onSave();
+    void onLoadSnapshot();
 private:
     void saveSettings();
     void restoreSettings();
 
     LocalProp* propertyFromPath(QByteArray path) const;
 
+    void createdRootProperty();
+
     QNetworkAccessManager* m_netAccess;
     QWebSocket m_webSocket;
     Ui::TemporaryWidget *ui;