Only start websocket connections if needed

src/mainwindow.cpp

@@ -105,10 +105,13 @@ MainWindow::MainWindow(QWidget *parent) :
 
     restoreSavedStates();
 
-    createWebsocket();
+    if (AppDataServer::getInstance()->isAppConnected()) {
+        createWebsocket();
+    }
 }
  
 void MainWindow::createWebsocket() {
+    qDebug() << "Listening for app connections on port 8237";
     // Create the websocket server, for listening to direct connections
     wsserver = new WSServer(8237, false, this);
 
@@ -117,6 +120,20 @@ void MainWindow::createWebsocket() {
                                                 AppDataServer::getInstance()->getSecretHex()));
 }
 
+void MainWindow::stopWebsocket() {
+    delete wsserver;
+    wsserver = nullptr;
+
+    delete wormhole;
+    wormhole = nullptr;
+
+    qDebug() << "Websockets for app connections shut down";
+}
+
+bool MainWindow::isWebsocketListening() {
+    return wsserver != nullptr;
+}
+
 void MainWindow::replaceWormholeClient(WormholeClient* newClient) {
     delete wormhole;
     wormhole = newClient;

src/mainwindow.h

@@ -46,6 +46,9 @@ public:
     void setDefaultPayFrom();
 
     void replaceWormholeClient(WormholeClient* newClient);
+    bool isWebsocketListening();
+    void createWebsocket();
+    void stopWebsocket();
 
     Ui::MainWindow*     ui;
 
@@ -107,8 +110,6 @@ private:
 
     void restoreSavedStates();
 
-    void createWebsocket();
-
     WSServer*       wsserver = nullptr;
     WormholeClient* wormhole = nullptr;
 

src/websockets.cpp

@@ -170,6 +170,19 @@ QDateTime  AppDataServer::getLastSeenTime() {
     return QDateTime::fromSecsSinceEpoch(QSettings().value("mobileapp/lastseentime", 0).toLongLong());
 }
 
+void AppDataServer::setConnectedName(QString name) {
+    QSettings().setValue("mobileapp/connectedname", name);
+}
+
+QString AppDataServer::getConnectedName() {
+    return QSettings().value("mobileapp/connectedname", "").toString();
+}
+
+bool AppDataServer::isAppConnected() {
+    return !getConnectedName().isEmpty() && 
+        getLastSeenTime().daysTo(QDateTime::currentDateTime()) < 14;
+}
+
 void AppDataServer::connectAppDialog(MainWindow* parent) {
     QDialog d(parent);
     ui = new Ui_MobileAppConnector();
@@ -190,8 +203,18 @@ void AppDataServer::connectAppDialog(MainWindow* parent) {
         ui->txtConnStr->selectAll();
     });
 
+    // If we're not listening for the app, then start the websockets
+    if (!parent->isWebsocketListening()) {
+        parent->createWebsocket();
+    }
+
     d.exec();
 
+    // If there is nothing connected when the dialog exits, then shutdown the websockets
+    if (!isAppConnected()) {
+        parent->stopWebsocket();
+    }
+
     // Cleanup
     tempSecret = "";
     delete tempWormholeClient;
@@ -252,7 +275,7 @@ void AppDataServer::updateConnectedUI() {
     if (ui == nullptr)
         return;
 
-    auto remoteName = QSettings().value("mobileapp/connectedname", "").toString();
+    auto remoteName = getConnectedName();
 
     ui->lblRemoteName->setText(remoteName.isEmpty() ?  "(Not connected to any device)" : remoteName);
     ui->lblLastSeen->setText(remoteName.isEmpty() ? "" : getLastSeenTime().toString(Qt::SystemLocaleLongDate));
@@ -267,10 +290,10 @@ QString AppDataServer::getNonceHex(NonceType nt) {
     if (nt == NonceType::LOCAL) {
         // The default local nonce starts from 1, to always keep it odd
         auto defaultLocalNonce = "01" + QString("00").repeated(crypto_secretbox_NONCEBYTES-1);
-        hex = s.value("mobileapp/localnonce", defaultLocalNonce).toString();
+        hex = s.value("mobileapp/localnoncehex", defaultLocalNonce).toString();
     }
     else {
-        hex = s.value("mobileapp/remotenonce", QString("00").repeated(crypto_secretbox_NONCEBYTES)).toString();
+        hex = s.value("mobileapp/remotenoncehex", QString("00").repeated(crypto_secretbox_NONCEBYTES)).toString();
     }
     return hex;
 }
@@ -279,10 +302,10 @@ void AppDataServer::saveNonceHex(NonceType nt, QString noncehex) {
     QSettings s;
     assert(noncehex.length() == crypto_secretbox_NONCEBYTES * 2);
     if (nt == NonceType::LOCAL) {
-        s.setValue("mobileapp/localnonce", noncehex);
+        s.setValue("mobileapp/localnoncehex", noncehex);
     }
     else {
-        s.setValue("mobileapp/remotenonce", noncehex);
+        s.setValue("mobileapp/remotenoncehex", noncehex);
     }
     s.sync();
 }
@@ -324,8 +347,6 @@ QString AppDataServer::encryptOutgoing(QString msg) {
     sodium_memzero(encryptedHex, encryptedHexSize);
     sodium_bin2hex(encryptedHex, encryptedHexSize, encrpyted, msgSize + crypto_secretbox_MACBYTES);
 
-    qDebug() << "Encrypted to " << QString(encryptedHex);
-
     auto json =  QJsonDocument(QJsonObject{
             {"nonce", QString(newLocalNonce)},
             {"payload", QString(encryptedHex)},
@@ -634,10 +655,7 @@ void AppDataServer::processGetInfo(QJsonObject jobj, MainWindow* mainWindow, QWe
         }
     }
 
-    {
-        QSettings s;
-        s.setValue("mobileapp/connectedname", connectedName);
-    }
+    setConnectedName(connectedName);
 
     auto r = QJsonDocument(QJsonObject{
         {"version", 1.0},

src/websockets.h

@@ -99,6 +99,10 @@ public:
     void          saveLastSeenTime();
     QDateTime     getLastSeenTime();
 
+    void          setConnectedName(QString name);   
+    QString       getConnectedName();
+    bool          isAppConnected();
+
     QString       connDesc(AppConnectionType t);
 
     void               saveLastConnectedOver(AppConnectionType type);