From a5a32a172296e6cf79ff43348bf4a90e5c16bb69 Mon Sep 17 00:00:00 2001
From: Klaus Basan <klaus.basan@klausbasan.de>
Date: Wed, 27 Sep 2017 19:35:09 +0200
Subject: [PATCH] Ref T165, directly display distributions info

* use digest signal to avoid unnecessary signals
* better user experience by directly displaying info
---
 .../components/distributioninfocomponent.cpp  | 26 +++++++++----------
 .../components/distributioninfocomponent.h    |  6 ++++-
 2 files changed, 17 insertions(+), 15 deletions(-)

diff --git a/src/blackgui/components/distributioninfocomponent.cpp b/src/blackgui/components/distributioninfocomponent.cpp
index 2b6a753cf..90658a467 100644
--- a/src/blackgui/components/distributioninfocomponent.cpp
+++ b/src/blackgui/components/distributioninfocomponent.cpp
@@ -36,16 +36,14 @@ namespace BlackGui
             ui->lbl_NewVersionUrl->setOpenExternalLinks(true);
 
             // use version signal as trigger for completion
-            if (!m_distributionsInfo.get().isEmpty())
+            const CDistributionList distributions = m_distributionsInfo.get();
+            if (!distributions.isEmpty())
             {
                 // we have at least cached data:
                 // in case CGuiApplication::distributionInfoAvailable never comes/was already sent
-                QTimer::singleShot(15 * 1000, this, [ = ]
-                {
-                    // use this as timeout failover with cached data
-                    if (m_distributionsLoaded) { return; }
-                    this->ps_loadedDistributionInfo(true);
-                });
+                // 1) we do not know if we missed the signal, the server is down etc
+                // 2) for better user experience we display straight away, it will overridden if the signal will br received
+                this->ps_loadedDistributionInfo(true);
             }
 
             Q_ASSERT_X(sGui, Q_FUNC_INFO, "Need sGui");
@@ -76,7 +74,6 @@ namespace BlackGui
                 if (msgs.isSuccess())
                 {
                     ui->le_LatestVersion->setText("");
-                    m_distributionsLoaded = false; // reset
                 }
             }
         }
@@ -85,20 +82,16 @@ namespace BlackGui
         {
             if (!success)
             {
-                m_distributionsLoaded = false;
                 ui->pb_CheckForUpdates->setToolTip("");
                 CLogMessage(this).warning("Loading setup or distribution information failed");
                 return;
             }
 
-            // only emit once
-            if (m_distributionsLoaded) { return; }
-            m_distributionsLoaded = true;
             this->ps_channelChanged();
             ui->pb_CheckForUpdates->setToolTip(sApp->getLastSuccesfulDistributionUrl());
 
-            // emit only after all has been set
-            emit this->distributionInfoAvailable(success);
+            // emit via digest signal
+            m_dsDistributionAvailable.inputSignal();
         }
 
         void CDistributionInfoComponent::ps_changedDistributionCache()
@@ -128,6 +121,11 @@ namespace BlackGui
             }
         }
 
+        void CDistributionInfoComponent::triggerInfoAvailableSignal()
+        {
+            emit this->distributionInfoAvailable(true);
+        }
+
         void CDistributionInfoComponent::ps_channelChanged()
         {
             const CDistributionList distributions(m_distributionsInfo.get());
diff --git a/src/blackgui/components/distributioninfocomponent.h b/src/blackgui/components/distributioninfocomponent.h
index 6a62d0d6d..020d7f054 100644
--- a/src/blackgui/components/distributioninfocomponent.h
+++ b/src/blackgui/components/distributioninfocomponent.h
@@ -16,6 +16,7 @@
 #include "blackgui/blackguiexport.h"
 #include "blackmisc/db/distributionlist.h"
 #include "blackmisc/settingscache.h"
+#include "blackmisc/digestsignal.h"
 #include <QFrame>
 
 namespace Ui { class CDistributionInfoComponent; }
@@ -77,15 +78,18 @@ namespace BlackGui
         private:
             QScopedPointer<Ui::CDistributionInfoComponent> ui;
             QScopedPointer<CInstallXSwiftBusDialog> m_installXSwiftBusDialog; //!< dialog, install XSwiftXBus
-            bool m_distributionsLoaded = false; //!< distribution info loaded
             QString m_newVersionAvailable; //!< new version number if any
             BlackMisc::Db::CDistribution m_currentDistribution; //!< current distribution
             BlackMisc::CDataReadOnly<BlackMisc::Db::TDistributionsInfo> m_distributionsInfo { this, &CDistributionInfoComponent::ps_changedDistributionCache }; //!< version cache
             BlackMisc::CSetting<BlackCore::Application::TDistribution> m_distributionSetting { this }; //!< channel/platform selected
+            BlackMisc::CDigestSignal m_dsDistributionAvailable { this, &CDistributionInfoComponent::triggerInfoAvailableSignal, 10000, 2 };
 
             //! Save the current settings
             void saveSettings();
 
+            //! Trigger the CDistributionInfoComponent::distributionInfoAvailable signal
+            void triggerInfoAvailableSignal();
+
             //! Selected platform from UI or guessed platform
             QString getSelectedOrGuessedPlatform() const;
         };