Add versiontagscan table to track the version of tag processing used …

…to populate the library. Replace use of GUI setting MusicNeedsUpdate with read/write to database.

xbmc/music/MusicDatabase.cpp

@@ -192,6 +192,10 @@ void CMusicDatabase::CreateTables()
 
   CLog::Log(LOGINFO, "create cue table");
   m_pDS->exec("CREATE TABLE cue (idPath integer, strFileName text, strCuesheet text)");
+
+  CLog::Log(LOGINFO, "create versiontagscan table");
+  m_pDS->exec("CREATE TABLE versiontagscan (idVersion integer, iNeedsScan integer)");
+  m_pDS->exec(PrepareSQL("INSERT INTO versiontagscan (idVersion, iNeedsScan) values(%i, 0)", GetSchemaVersion()));
 }
 
 void CMusicDatabase::CreateAnalytics()
@@ -4662,8 +4666,6 @@ void CMusicDatabase::UpdateTables(int version)
   if (version < 53)
   {
     m_pDS->exec("ALTER TABLE song ADD dateAdded text");
-    CMediaSettings::GetInstance().SetMusicNeedsUpdate(53);
-    CServiceBroker::GetSettings().Save();
   }
   if (version < 54)
   {
@@ -4958,17 +4960,78 @@ void CMusicDatabase::UpdateTables(int version)
     //Remove temp indices, full analytics for database created later
     m_pDS->exec("DROP INDEX idxSongArtist1 ON song_artist");
     m_pDS->exec("DROP INDEX idxAlbumArtist1 ON album_artist");
-
-    // Prompt for rescan of library to read tags that were not processed by previous versions
-    // and accomodate changes to the way some tags are processed
-    CMediaSettings::GetInstance().SetMusicNeedsUpdate(60);
-    CServiceBroker::GetSettings().Save();
   }
+  if (version < 61)
+  {
+    // Create versiontagscan table
+    m_pDS->exec("CREATE TABLE versiontagscan (idVersion integer, iNeedsScan integer)");
+    m_pDS->exec("INSERT INTO versiontagscan (idVersion, iNeedsScan) values(0, 0)");
+  }
+
+  // Set the verion of tag scanning required. 
+  // Not every schema change requires the tags to be rescanned, set to the highest schema version 
+  // that needs this. Forced rescanning (of music files that have not changed since they were 
+  // previously scanned) also accommodates any changes to the way tags are processed 
+  // e.g. read tags that were not processed by previous versions.
+  // The original db version when the tags were scanned, and the minimal db version needed are 
+  // later used to determine if a forced rescan should be prompted
+
+  // The last schema change needing forced rescanning was 60.
+  // Mostly because of the new tags processed by v17 rather than a schema change.
+  SetMusicNeedsTagScan(60);
+
+  // After all updates, store the original db version. 
+  // This indicates the version of tag processing that was used to populate db
+  SetMusicTagScanVersion(version);
 }
 
 int CMusicDatabase::GetSchemaVersion() const
 {
-  return 60;
+  return 61;
+}
+
+int CMusicDatabase::GetMusicNeedsTagScan()
+{
+  try
+  {
+    if (NULL == m_pDB.get()) return -1;
+    if (NULL == m_pDS.get()) return -1;
+
+    std::string sql = "SELECT * FROM versiontagscan";
+    if (!m_pDS->query(sql)) return -1;
+
+    if (m_pDS->num_rows() != 1)
+    {
+      m_pDS->close();
+      return -1;
+    }
+
+    int idVersion = m_pDS->fv("idVersion").get_asInt();
+    int iNeedsScan = m_pDS->fv("iNeedsScan").get_asInt();
+    m_pDS->close();
+    if (idVersion < iNeedsScan)
+      return idVersion;
+    else
+      return 0;
+  }
+  catch (...)
+  {
+    CLog::Log(LOGERROR, "%s failed", __FUNCTION__);
+  }
+  return -1;
+}
+
+void CMusicDatabase::SetMusicNeedsTagScan(int version)
+{
+  m_pDS->exec(PrepareSQL("UPDATE versiontagscan SET iNeedsScan=%i", version));
+}
+
+void CMusicDatabase::SetMusicTagScanVersion(int version /* = 0 */)
+{
+  if (version == 0)
+    m_pDS->exec(PrepareSQL("UPDATE versiontagscan SET idVersion=%i", GetSchemaVersion()));
+  else
+    m_pDS->exec(PrepareSQL("UPDATE versiontagscan SET idVersion=%i", version));
 }
 
 unsigned int CMusicDatabase::GetSongIDs(const Filter &filter, std::vector<std::pair<int,int> > &songIDs)

xbmc/music/MusicDatabase.h

@@ -497,6 +497,26 @@ class CMusicDatabase : public CDatabase
    */
   std::string GetArtistArtForItem(int mediaId, const std::string &mediaType, const std::string &artType);
 
+  /////////////////////////////////////////////////
+  // Tag Scan Version
+  /////////////////////////////////////////////////
+  /*! \brief Check if music files need all tags rescanning regardless of file being unchanged 
+  because the tag processing has changed (which may happen without db version changes) since they
+  where last scanned.
+  \return -1 if an error occured, 0 if no scan is needed, or the version number of tags if not the same as current.
+  */
+  virtual int GetMusicNeedsTagScan();
+
+  /*! \brief Set minimum version number of db needed when tag data scanned from music files
+  \param version the version number of db
+  */
+  void SetMusicNeedsTagScan(int version);
+
+  /*! \brief Set the version number of tag data 
+  \param version the version number of db when tags last scanned, 0 (default) means current db version
+  */
+  void SetMusicTagScanVersion(int version = 0);
+
 protected:
   std::map<std::string, int> m_artistCache;
   std::map<std::string, int> m_genreCache;

xbmc/music/windows/GUIWindowMusicBase.cpp

@@ -1308,7 +1308,7 @@ void CGUIWindowMusicBase::OnInitWindow()
   CGUIMediaWindow::OnInitWindow();
   // Prompt for rescan of library to read music file tags that were not processed by previous versions
   // and accomodate any changes to the way some tags are processed
-  if (CMediaSettings::GetInstance().GetMusicNeedsUpdate() != 0)
+  if (m_musicdatabase.GetMusicNeedsTagScan() != 0)
   {
     if (g_infoManager.GetLibraryBool(LIBRARY_HAS_MUSIC) && !g_application.IsMusicScanning())
     {
@@ -1324,15 +1324,13 @@ void CGUIWindowMusicBase::OnInitWindow()
         if (CServiceBroker::GetSettings().GetBool(CSettings::SETTING_MUSICLIBRARY_BACKGROUNDUPDATE))
           flags |= CMusicInfoScanner::SCAN_BACKGROUND;
         g_application.StartMusicScan("", true, flags);
-        CMediaSettings::GetInstance().SetMusicNeedsUpdate(0); // once is enough (user may interrupt, but that's up to them)
-        CServiceBroker::GetSettings().Save();
+        m_musicdatabase.SetMusicTagScanVersion(); // once is enough (user may interrupt, but that's up to them)
       }
     }
     else
     {
       // no need to force a rescan if there's no music in the library or if a library scan is already active
-      CMediaSettings::GetInstance().SetMusicNeedsUpdate(0);
-      CServiceBroker::GetSettings().Save();
+      m_musicdatabase.SetMusicTagScanVersion();
     }
   }
 }