[DeckShare] Time the share-list round trip and backstop silently-destroyed intent chains

cockatrice/src/interface/intents/intent_open_shared_deck.cpp

@@ -43,7 +43,11 @@ bool IntentOpenSharedDeck::checkPrecondition() const
 void IntentOpenSharedDeck::onPreconditionSatisfied()
 {
     // Resolve the share token to its items first; a share can contain more than
-    // one deck, and each item is downloaded by id.
+    // one deck, and each item is downloaded by id. Time the round trip like the
+    // downloads, so a silent server cannot hang the chain forever.
+    listPhase = true;
+    downloadTimer->start();
+
     Command_DeckShareList cmd;
     cmd.set_token(context->shareToken.toStdString());
 
@@ -59,6 +63,9 @@ void IntentOpenSharedDeck::onPreconditionNotSatisfied()
 
 void IntentOpenSharedDeck::listShareFinished(const Response &response, const CommandContainer & /* commandContainer */)
 {
+    downloadTimer->stop();
+    listPhase = false;
+
     if (response.response_code() != Response::RespOk) {
         emitFailed(tr("The shared deck could not be found or has expired"));
         return;
@@ -177,6 +184,12 @@ void IntentOpenSharedDeck::onItemFailure(const QString &reason)
 
 void IntentOpenSharedDeck::onDownloadTimeout()
 {
+    // The list phase has no preview dialog yet to report progress into; fail the
+    // whole intent instead of letting the shared deck hang in limbo.
+    if (listPhase) {
+        emitFailed(tr("Timed out while loading the shared deck"));
+        return;
+    }
     onItemFailure(tr("Timed out while downloading the shared deck"));
 }
 

cockatrice/src/interface/intents/intent_open_shared_deck.h

@@ -51,6 +51,7 @@ private:
     QMap<int, QString> itemNames;
     QList<int> pendingItemIds;
     QList<LoadedDeck> loadedDecks;
+    bool listPhase = true;
     int currentItemId = 0;
     int totalItems = 0;
     int completedItems = 0;

cockatrice/src/interface/intents/url_parser.cpp

@@ -313,6 +313,10 @@ void IntentUrlParser::startNextChain()
     connect(finalIntent, &Intent::finished, this, [this]() { chainEnded(true); });
     connect(finalIntent, &Intent::failed, this, [this]() { chainEnded(false); });
     connect(finalIntent, &Intent::cancelled, this, [this]() { chainEnded(false); });
+    // Backstop: if the final intent is destroyed without emitting a terminal
+    // signal (e.g. a network error dropped it while running), end the chain so
+    // later links are not queued and dropped for the rest of the session.
+    chainBackstopConnection = connect(finalIntent, &QObject::destroyed, this, &IntentUrlParser::onChainIntentDestroyed);
 
     chain.intents.first()->execute();
 }
@@ -320,6 +324,7 @@ void IntentUrlParser::startNextChain()
 void IntentUrlParser::chainEnded(bool chainSucceeded)
 {
     chainRunning = false;
+    QObject::disconnect(chainBackstopConnection);
 
     const PendingIntentChain chain = pendingChains.takeFirst();
 
@@ -338,6 +343,15 @@ void IntentUrlParser::chainEnded(bool chainSucceeded)
     }
 }
 
+void IntentUrlParser::onChainIntentDestroyed()
+{
+    if (!chainRunning) {
+        return;
+    }
+    qCWarning(UrlParserLog) << "Share-link intent destroyed without a terminal signal; ending its chain";
+    chainEnded(false);
+}
+
 void IntentUrlParser::restorePreviousServer(const PendingIntentChain &chain)
 {
     if (chain.previousServerHost.isEmpty()) {

cockatrice/src/interface/intents/url_parser.h

@@ -1,5 +1,6 @@
 #ifndef COCKATRICE_URL_PARSER_H
 #define COCKATRICE_URL_PARSER_H
+
 #include <QList>
 #include <QObject>
 #include <QUrlQuery>
@@ -29,7 +30,6 @@ struct PendingIntentChain
     QString migrationTargetHost;
     QString migrationTargetPort;
     bool pendingRestore = false;
-    bool succeeded = false;
 };
 
 /**
@@ -60,12 +60,16 @@ private:
     [[nodiscard]] bool isConnectedTo(const QString &hostname, const QString &port) const;
     void startNextChain();
     void chainEnded(bool chainSucceeded);
+    void onChainIntentDestroyed();
     void restorePreviousServer(const PendingIntentChain &chain);
     void restoreToPreviousServer(const PendingIntentChain &chain);
 
     MainWindow *mainWindow;
     QList<PendingIntentChain> pendingChains;
     bool chainRunning = false;
+    // Disconnects the destroyed-signal backstop once a chain ends, so an old
+    // intent's deferred deletion cannot end the chain that runs after it.
+    QMetaObject::Connection chainBackstopConnection;
 };
 
 #endif // COCKATRICE_URL_PARSER_H