flatpak: do not fetch the size of a resource several times in parallel

There is no need for it. Makes the operation more expensive and it makes
the output too verbose when there's problems.

libdiscover/backends/FlatpakBackend/FlatpakBackend.cpp

@@ -1063,6 +1063,10 @@ bool FlatpakBackend::updateAppSizeFromRemote(FlatpakInstallation *flatpakInstall
             return false;
         }
 
+        if (resource->propertyState(FlatpakResource::DownloadSize) == FlatpakResource::Fetching) {
+            return true;
+        }
+
         auto futureWatcher = new QFutureWatcher<FlatpakRunnables::SizeInformation>(this);
         connect(futureWatcher, &QFutureWatcher<FlatpakRunnables::SizeInformation>::finished, this, [this, resource, futureWatcher]() {
             auto value = futureWatcher->result();
@@ -1074,6 +1078,9 @@ bool FlatpakBackend::updateAppSizeFromRemote(FlatpakInstallation *flatpakInstall
             }
             futureWatcher->deleteLater();
         });
+        resource->setPropertyState(FlatpakResource::DownloadSize, FlatpakResource::Fetching);
+        resource->setPropertyState(FlatpakResource::InstalledSize, FlatpakResource::Fetching);
+
         futureWatcher->setFuture(QtConcurrent::run(&m_threadPool, &FlatpakRunnables::fetchFlatpakSize, flatpakInstallation, resource));
     }
 

libdiscover/backends/FlatpakBackend/FlatpakResource.cpp

@@ -349,7 +349,7 @@ QString FlatpakResource::sizeDescription()
 {
     KFormat f;
     if (!isInstalled() || canUpgrade()) {
-        if (propertyState(DownloadSize) == NotKnownYet || propertyState(InstalledSize) == NotKnownYet) {
+        if (propertyState(DownloadSize) == NotKnownYet || propertyState(InstalledSize) == NotKnownYet || propertyState(DownloadSize) == Fetching || propertyState(InstalledSize) == Fetching) {
             return i18n("Retrieving size information");
         } else if (propertyState(DownloadSize) == UnknownOrFailed || propertyState(InstalledSize) == UnknownOrFailed) {
             return i18n("Unknown size");
@@ -357,7 +357,7 @@ QString FlatpakResource::sizeDescription()
             return i18nc("@info app size", "%1 to download, %2 on disk", f.formatByteSize(downloadSize()), f.formatByteSize(installedSize()));
         }
     } else {
-        if (propertyState(InstalledSize) == NotKnownYet) {
+        if (propertyState(InstalledSize) == NotKnownYet || propertyState(InstalledSize) == Fetching) {
             return i18n("Retrieving size information");
         } else if (propertyState(InstalledSize) == UnknownOrFailed) {
             return i18n("Unknown size");

libdiscover/backends/FlatpakBackend/FlatpakResource.h

@@ -38,6 +38,7 @@ public:
         NotKnownYet = 0,
         AlreadyKnown,
         UnknownOrFailed,
+        Fetching,
     };
     Q_ENUM(PropertyState)