Playlist track sort order cleanup, part two.

src/core/library/IIndexer.h

@@ -53,7 +53,7 @@ namespace musik { namespace core {
             enum class SyncType{
                 All,
                 Local,
-                Sources,
+                Sources
             };
 
             virtual ~IIndexer() { }

src/core/library/Indexer.cpp

@@ -695,46 +695,57 @@ void Indexer::SyncCleanup() {
         }
     }
 
-    /* make sure playlist sort orders are always sequential without holes. we
-    do this anyway, as playlists are updated, but there's no way to guarantee
-    it stays this way -- plugins, external processes, etc can cause problems */
-    {
-        db::Statement playlists("SELECT DISTINCT id FROM playlists", this->dbConnection);
-
-        while (playlists.Step() == db::Row) {
-            db::Statement tracks(
-                "SELECT track_external_id, sort_order "
-                "FROM playlist_tracks WHERE playlist_id=? "
-                "ORDER BY sort_order",
-                this->dbConnection);
-
-            int64_t playlistId = playlists.ColumnInt64(0);
-            tracks.BindInt64(0, playlistId);
-
-            db::Statement update(
-                "UPDATE playlist_tracks "
-                "SET sort_order=? "
-                "WHERE track_external_id=? AND sort_order=?",
-                this->dbConnection);
-
-            int order = 0;
-            while (tracks.Step() == db::Row) {
-                std::string externalId = tracks.ColumnText(0);
-                int sortOrder = tracks.ColumnInt32(1);
-
-                update.ResetAndUnbind();
-                update.BindInt32(0, order++);
-                update.BindText(1, externalId);
-                update.BindInt32(2, sortOrder);
-                update.Step();
-            }
-        }
-    }
+    this->SyncPlaylistTracksOrder();
 
     /* optimize and shrink */
     this->dbConnection.Execute("VACUUM");
 }
 
+void Indexer::SyncPlaylistTracksOrder() {
+    /* make sure playlist sort orders are always sequential without holes. we
+    do this anyway, as playlists are updated, but there's no way to guarantee
+    it stays this way -- plugins, external processes, etc can cause problems */
+
+    db::Statement playlists(
+        "SELECT DISTINCT id FROM playlists",
+        this->dbConnection);
+
+    db::Statement tracks(
+        "SELECT track_external_id, sort_order "
+        "FROM playlist_tracks WHERE playlist_id=? "
+        "ORDER BY sort_order",
+        this->dbConnection);
+
+    db::Statement update(
+        "UPDATE playlist_tracks "
+        "SET sort_order=? "
+        "WHERE track_external_id=? AND sort_order=?",
+        this->dbConnection);
+
+    struct Record { std::string id; int order; };
+
+    while (playlists.Step() == db::Row) {
+        tracks.ResetAndUnbind();
+        tracks.BindInt64(0, playlists.ColumnInt64(0));
+
+        /* gotta cache these in memory because we can't update the
+        table at the same time we're iterating */
+        std::vector<Record> records;
+        while (tracks.Step() == db::Row) {
+            records.push_back({ tracks.ColumnText(0), tracks.ColumnInt32(1) });
+        }
+
+        int order = 0;
+        for (auto& r : records) {
+            update.ResetAndUnbind();
+            update.BindInt32(0, order++);
+            update.BindText(1, r.id);
+            update.BindInt32(2, r.order);
+            update.Step();
+        }
+    }
+}
+
 void Indexer::GetPaths(std::vector<std::string>& paths) {
     boost::mutex::scoped_lock lock(this->stateMutex);
     std::copy(this->paths.begin(), this->paths.end(), std::back_inserter(paths));

src/core/library/Indexer.h

@@ -120,6 +120,7 @@ namespace musik { namespace core {
             void FinalizeSync(const SyncContext& context);
             void SyncDelete();
             void SyncCleanup();
+            void SyncPlaylistTracksOrder();
             musik::core::sdk::ScanResult SyncSource(musik::core::sdk::IIndexerSource* source);
             void ProcessAddRemoveQueue();
             void SyncOptimize();