settings: add ISettingsHandler

3 files changed, 155 insertions, 2 deletions

diff --git a/xbmc/settings/ISettingsHandler.h b/xbmc/settings/ISettingsHandler.h
new file mode 100644
index 0000000000..15804377c3
--- /dev/null
+++ b/xbmc/settings/ISettingsHandler.h
@@ -0,0 +1,58 @@
+#pragma once
+/*
+ *      Copyright (C) 2013 Team XBMC
+ *      http://xbmc.org
+ *
+ *  This Program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2, or (at your option)
+ *  any later version.
+ *
+ *  This Program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with XBMC; see the file COPYING.  If not, see
+ *  <http://www.gnu.org/licenses/>.
+ *
+ */
+
+class ISettingsHandler
+{
+public:
+  virtual ~ISettingsHandler() { }
+
+  /*!
+   \brief Settings loading has been initiated.
+
+   \return True if the settings should be loaded, false if the loading should be aborted.
+   */
+  virtual bool OnSettingsLoading() { return true; }
+  /*!
+   \brief Settings have been loaded.
+
+   This callback can be used to trigger loading other settings.
+   */
+  virtual void OnSettingsLoaded() { }
+  /*!
+   \brief Settings saving has been initiated.
+
+   \return True if the settings should be saved, false if the saving should be aborted.
+   */
+  virtual bool OnSettingsSaving() const { return true; }
+  /*!
+   \brief Settings have been saved.
+
+   This callback can be used to trigger saving other settings.
+   */
+  virtual void OnSettingsSaved() const { }
+  /*!
+   \brief Settings have been cleared.
+
+   This callback can be used to trigger clearing any state variables
+   (e.g. before re-loading the settings).
+   */
+  virtual void OnSettingsCleared() { }
+};
diff --git a/xbmc/settings/Settings.cpp b/xbmc/settings/Settings.cpp
index 3bb10695da..7880b59d1b 100644
--- a/xbmc/settings/Settings.cpp
+++ b/xbmc/settings/Settings.cpp
@@ -59,6 +59,7 @@
 #ifdef HAS_UPNP
 #include "network/upnp/UPnPSettings.h"
 #endif
+#include "threads/SingleLock.h"
 #include "utils/RssManager.h"
 
 using namespace std;
@@ -68,6 +69,24 @@ CSettings::CSettings(void)
 {
 }
 
+void CSettings::RegisterSettingsHandler(ISettingsHandler *settingsHandler)
+{
+  if (settingsHandler == NULL)
+    return;
+
+  CSingleLock lock(m_critical);
+  m_settingsHandlers.insert(settingsHandler);
+}
+
+void CSettings::UnregisterSettingsHandler(ISettingsHandler *settingsHandler)
+{
+  if (settingsHandler == NULL)
+    return;
+
+  CSingleLock lock(m_critical);
+  m_settingsHandlers.erase(settingsHandler);
+}
+
 void CSettings::Initialize()
 {
   RESOLUTION_INFO res;
@@ -142,7 +161,9 @@ void CSettings::Initialize()
 }
 
 CSettings::~CSettings(void)
-{ }
+{
+  m_settingsHandlers.clear();
+}
 
 
 void CSettings::Save() const
@@ -170,6 +191,9 @@ bool CSettings::Reset()
 
 bool CSettings::Load()
 {
+  if (!OnSettingsLoading())
+    return false;
+
   CSpecialProtocol::SetProfilePath(GetProfileUserDataFolder());
   CLog::Log(LOGNOTICE, "loading %s", GetSettingsFile().c_str());
   if (!LoadSettings(GetSettingsFile()))
@@ -183,6 +207,8 @@ bool CSettings::Load()
   CRssManager::Get().Load();
   LoadUserFolderLayout();
 
+  OnSettingsLoaded();
+
   return true;
 }
 
@@ -829,6 +855,9 @@ bool CSettings::SaveSettings(const CStdString& strSettingsFile, CGUISettings *lo
   if (!pRoot) return false;
   // write our tags one by one - just a big list for now (can be flashed up later)
 
+  if (!OnSettingsSaving())
+    return false;
+
   // mymusic settings
   TiXmlElement musicNode("mymusic");
   TiXmlNode *pNode = pRoot->InsertEndChild(musicNode);
@@ -947,6 +976,8 @@ bool CSettings::SaveSettings(const CStdString& strSettingsFile, CGUISettings *lo
   // For mastercode
   SaveProfiles( PROFILES_FILE );
 
+  OnSettingsSaved();
+
   // save the file
   return xmlDoc.SaveFile(strSettingsFile);
 }
@@ -1433,6 +1464,8 @@ void CSettings::Clear()
   CUPnPSettings::Get().Clear();
 #endif
   CRssManager::Get().Clear();
+
+  OnSettingsCleared();
 }
 
 int CSettings::TranslateSkinString(const CStdString &setting)
@@ -1820,3 +1853,48 @@ void CSettings::LoadMasterForLogin()
   if (m_currentProfile != 0)
     LoadProfile(0);
 }
+
+bool CSettings::OnSettingsLoading()
+{
+  CSingleLock lock(m_critical);
+  for (SettingsHandlers::const_iterator it = m_settingsHandlers.begin(); it != m_settingsHandlers.end(); it++)
+  {
+    if (!(*it)->OnSettingsLoading())
+      return false;
+  }
+
+  return true;
+}
+
+void CSettings::OnSettingsLoaded()
+{
+  CSingleLock lock(m_critical);
+  for (SettingsHandlers::const_iterator it = m_settingsHandlers.begin(); it != m_settingsHandlers.end(); it++)
+    (*it)->OnSettingsLoaded();
+}
+
+bool CSettings::OnSettingsSaving() const
+{
+  CSingleLock lock(m_critical);
+  for (SettingsHandlers::const_iterator it = m_settingsHandlers.begin(); it != m_settingsHandlers.end(); it++)
+  {
+    if (!(*it)->OnSettingsSaving())
+      return false;
+  }
+
+  return true;
+}
+
+void CSettings::OnSettingsSaved() const
+{
+  CSingleLock lock(m_critical);
+  for (SettingsHandlers::const_iterator it = m_settingsHandlers.begin(); it != m_settingsHandlers.end(); it++)
+    (*it)->OnSettingsSaved();
+}
+
+void CSettings::OnSettingsCleared()
+{
+  CSingleLock lock(m_critical);
+  for (SettingsHandlers::const_iterator it = m_settingsHandlers.begin(); it != m_settingsHandlers.end(); it++)
+    (*it)->OnSettingsCleared();
+}
diff --git a/xbmc/settings/Settings.h b/xbmc/settings/Settings.h
index 050f8d6f04..0075f1d674 100644
--- a/xbmc/settings/Settings.h
+++ b/xbmc/settings/Settings.h
@@ -43,14 +43,17 @@
 #endif
 #endif // MID
 
+#include "settings/ISettingsHandler.h"
 #include "settings/VideoSettings.h"
 #include "Profile.h"
 #include "view/ViewState.h"
 #include "guilib/Resolution.h"
 #include "guilib/GraphicContext.h"
+#include "threads/CriticalSection.h"
 
 #include <vector>
 #include <map>
+#include <set>
 
 #define CACHE_AUDIO 0
 #define CACHE_VIDEO 1
@@ -100,12 +103,15 @@ class TiXmlElement;
 class TiXmlNode;
 class CMediaSource;
 
-class CSettings
+class CSettings : private ISettingsHandler
 {
 public:
   CSettings(void);
   virtual ~CSettings(void);
 
+  void RegisterSettingsHandler(ISettingsHandler *settingsHandler);
+  void UnregisterSettingsHandler(ISettingsHandler *settingsHandler);
+
   void Initialize();
 
   bool Load();
@@ -382,6 +388,17 @@ protected:
   void LoadUserFolderLayout();
 
 private:
+  // implementation of ISettingsHandler
+  virtual bool OnSettingsLoading();
+  virtual void OnSettingsLoaded();
+  virtual bool OnSettingsSaving() const;
+  virtual void OnSettingsSaved() const;
+  virtual void OnSettingsCleared();
+
+  CCriticalSection m_critical;
+  typedef std::set<ISettingsHandler*> SettingsHandlers;
+  SettingsHandlers m_settingsHandlers;
+
   std::vector<CProfile> m_vecProfiles;
   std::map<CStdString, int> m_watchMode;
   bool m_usingLoginScreen;