fix(playback): ReplayGain prefetch, gapless UI sync, library peak column (#1231)

src-tauri/crates/psysonic-library/migrations/015_replay_gain_peak.sql

@@ -0,0 +1,2 @@
+-- ReplayGain track peak for anti-clipping bind (OpenSubsonic replayGain.trackPeak).
+ALTER TABLE track ADD COLUMN replay_gain_peak REAL;

src-tauri/crates/psysonic-library/src/advanced_search.rs

@@ -1438,6 +1438,7 @@ mod tests {
             bpm: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             content_hash: None,
             server_updated_at: None,
             server_created_at: None,

src-tauri/crates/psysonic-library/src/artist_lossless_browse.rs

@@ -213,6 +213,7 @@ mod tests {
             bpm: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             content_hash: None,
             server_updated_at: None,
             server_created_at: None,

src-tauri/crates/psysonic-library/src/browse_support.rs

@@ -208,6 +208,7 @@ mod tests {
             bpm: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             content_hash: None,
             server_updated_at: None,
             server_created_at: None,

src-tauri/crates/psysonic-library/src/commands.rs

@@ -1492,6 +1492,7 @@ mod tests {
             bpm: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             content_hash: Some(format!("hash-{id}")),
             server_updated_at: None,
             server_created_at: None,

src-tauri/crates/psysonic-library/src/cross_server.rs

@@ -212,6 +212,7 @@ mod tests {
             bpm: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             content_hash: None,
             server_updated_at: None,
             server_created_at: None,

src-tauri/crates/psysonic-library/src/dto.rs

@@ -106,6 +106,7 @@ pub struct LibraryTrackDto {
     pub bpm_source: Option<String>,
     pub replay_gain_track_db: Option<f64>,
     pub replay_gain_album_db: Option<f64>,
+    pub replay_gain_peak: Option<f64>,
 
     pub server_updated_at: Option<i64>,
     pub server_created_at: Option<i64>,
@@ -157,6 +158,7 @@ impl LibraryTrackDto {
             bpm_source: None,
             replay_gain_track_db: row.replay_gain_track_db,
             replay_gain_album_db: row.replay_gain_album_db,
+            replay_gain_peak: row.replay_gain_peak,
             server_updated_at: row.server_updated_at,
             server_created_at: row.server_created_at,
             synced_at: row.synced_at,
@@ -750,6 +752,7 @@ mod tests {
             bpm: Some(120),
             replay_gain_track_db: Some(-1.2),
             replay_gain_album_db: Some(-0.8),
+            replay_gain_peak: Some(0.95),
             content_hash: Some("deadbeef".into()),
             server_updated_at: Some(1_700_000_000),
             server_created_at: Some(1_699_000_000),
@@ -780,6 +783,7 @@ mod tests {
             "mbidRecording",
             "replayGainTrackDb",
             "replayGainAlbumDb",
+            "replayGainPeak",
             "serverUpdatedAt",
             "syncedAt",
             "rawJson",

src-tauri/crates/psysonic-library/src/genre_album_browse.rs

@@ -230,6 +230,7 @@ mod tests {
             bpm: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             content_hash: None,
             server_updated_at: None,
             server_created_at: None,

src-tauri/crates/psysonic-library/src/genre_tags_backfill.rs

@@ -288,6 +288,7 @@ mod tests {
             bpm: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             content_hash: None,
             server_updated_at: None,
             server_created_at: None,

src-tauri/crates/psysonic-library/src/live_search.rs

@@ -375,6 +375,7 @@ fn map_live_hit_row(row: &rusqlite::Row<'_>, offset: usize) -> rusqlite::Result<
             mbid_recording: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             server_updated_at: None,
             server_created_at: None,
             synced_at: row.get(offset + 21)?,
@@ -429,6 +430,7 @@ mod tests {
             bpm: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             content_hash: None,
             server_updated_at: None,
             server_created_at: None,

src-tauri/crates/psysonic-library/src/lossless_albums.rs

@@ -180,6 +180,7 @@ mod tests {
             bpm: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             content_hash: None,
             server_updated_at: None,
             server_created_at: None,

src-tauri/crates/psysonic-library/src/repos/artist.rs

@@ -233,6 +233,7 @@ mod tests {
             bpm: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             content_hash: None,
             server_updated_at: None,
             server_created_at: None,

src-tauri/crates/psysonic-library/src/repos/play_session/tests.rs

@@ -34,6 +34,7 @@ fn seed_track(store: &LibraryStore, server_id: &str, track_id: &str, duration_se
             bpm: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             content_hash: None,
             server_updated_at: None,
             server_created_at: None,
@@ -79,6 +80,7 @@ fn row_with_id_hash(server: &str, id: &str, hash: &str, path: &str) -> TrackRow
         bpm: None,
         replay_gain_track_db: None,
         replay_gain_album_db: None,
+        replay_gain_peak: None,
         content_hash: if hash.is_empty() {
             None
         } else {
@@ -503,6 +505,7 @@ fn recent_plays_includes_album_cover_metadata() {
             bpm: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             content_hash: None,
             server_updated_at: None,
             server_created_at: None,

src-tauri/crates/psysonic-library/src/repos/track.rs

@@ -53,6 +53,7 @@ pub struct TrackRow {
     pub bpm: Option<i64>,
     pub replay_gain_track_db: Option<f64>,
     pub replay_gain_album_db: Option<f64>,
+    pub replay_gain_peak: Option<f64>,
     pub content_hash: Option<String>,
     pub server_updated_at: Option<i64>,
     pub server_created_at: Option<i64>,
@@ -150,6 +151,7 @@ impl<'a> TrackRepository<'a> {
                         r.bpm,
                         r.replay_gain_track_db,
                         r.replay_gain_album_db,
+                        r.replay_gain_peak,
                         r.content_hash,
                         r.server_updated_at,
                         r.server_created_at,
@@ -189,6 +191,7 @@ impl<'a> TrackRepository<'a> {
                         r.bpm,
                         r.replay_gain_track_db,
                         r.replay_gain_album_db,
+                        r.replay_gain_peak,
                         r.content_hash,
                         r.server_updated_at,
                         r.server_created_at,
@@ -499,6 +502,7 @@ impl<'a> TrackRepository<'a> {
                     r.bpm,
                     r.replay_gain_track_db,
                     r.replay_gain_album_db,
+                    r.replay_gain_peak,
                     r.content_hash,
                     r.server_updated_at,
                     r.server_created_at,
@@ -673,27 +677,27 @@ const TRACK_COLUMNS: &str = "\
   album_artist, duration_sec, track_number, disc_number, year, genre, suffix, \
   bit_rate, size_bytes, cover_art_id, starred_at, user_rating, play_count, \
   played_at, server_path, library_id, isrc, mbid_recording, bpm, \
-  replay_gain_track_db, replay_gain_album_db, content_hash, server_updated_at, \
+  replay_gain_track_db, replay_gain_album_db, replay_gain_peak, content_hash, server_updated_at, \
   server_created_at, deleted, synced_at, raw_json";
 
 const SELECT_TRACK_BY_ID: &str = "SELECT server_id, id, title, title_sort, artist, artist_id, \
   album, album_id, album_artist, duration_sec, track_number, disc_number, year, genre, suffix, \
   bit_rate, size_bytes, cover_art_id, starred_at, user_rating, play_count, played_at, \
-  server_path, library_id, isrc, mbid_recording, bpm, replay_gain_track_db, replay_gain_album_db, \
+  server_path, library_id, isrc, mbid_recording, bpm, replay_gain_track_db, replay_gain_album_db, replay_gain_peak, \
   content_hash, server_updated_at, server_created_at, deleted, synced_at, raw_json \
   FROM track WHERE server_id = ?1 AND id = ?2 AND deleted = 0";
 
 const SELECT_TRACK_BY_ID_ONLY: &str = "SELECT server_id, id, title, title_sort, artist, artist_id, \
   album, album_id, album_artist, duration_sec, track_number, disc_number, year, genre, suffix, \
   bit_rate, size_bytes, cover_art_id, starred_at, user_rating, play_count, played_at, \
-  server_path, library_id, isrc, mbid_recording, bpm, replay_gain_track_db, replay_gain_album_db, \
+  server_path, library_id, isrc, mbid_recording, bpm, replay_gain_track_db, replay_gain_album_db, replay_gain_peak, \
   content_hash, server_updated_at, server_created_at, deleted, synced_at, raw_json \
   FROM track WHERE id = ?1 AND deleted = 0";
 
 const SELECT_TRACKS_BY_ALBUM: &str = "SELECT server_id, id, title, title_sort, artist, artist_id, \
   album, album_id, album_artist, duration_sec, track_number, disc_number, year, genre, suffix, \
   bit_rate, size_bytes, cover_art_id, starred_at, user_rating, play_count, played_at, \
-  server_path, library_id, isrc, mbid_recording, bpm, replay_gain_track_db, replay_gain_album_db, \
+  server_path, library_id, isrc, mbid_recording, bpm, replay_gain_track_db, replay_gain_album_db, replay_gain_peak, \
   content_hash, server_updated_at, server_created_at, deleted, synced_at, raw_json \
   FROM track WHERE server_id = ?1 AND album_id = ?2 AND deleted = 0 \
   ORDER BY disc_number ASC NULLS LAST, track_number ASC NULLS LAST, id ASC";
@@ -733,12 +737,13 @@ pub(crate) fn row_to_track_row(row: &rusqlite::Row<'_>) -> rusqlite::Result<Trac
         bpm: row.get(26)?,
         replay_gain_track_db: row.get(27)?,
         replay_gain_album_db: row.get(28)?,
-        content_hash: row.get(29)?,
-        server_updated_at: row.get(30)?,
-        server_created_at: row.get(31)?,
-        deleted: row.get::<_, i64>(32)? != 0,
-        synced_at: row.get(33)?,
-        raw_json: row.get(34)?,
+        replay_gain_peak: row.get(29)?,
+        content_hash: row.get(30)?,
+        server_updated_at: row.get(31)?,
+        server_created_at: row.get(32)?,
+        deleted: row.get::<_, i64>(33)? != 0,
+        synced_at: row.get(34)?,
+        raw_json: row.get(35)?,
     })
 }
 
@@ -748,60 +753,8 @@ INSERT INTO track (
   album_artist, duration_sec, track_number, disc_number, year, genre, suffix,
   bit_rate, size_bytes, cover_art_id, starred_at, user_rating, play_count,
   played_at, server_path, library_id, isrc, mbid_recording, bpm,
-  replay_gain_track_db, replay_gain_album_db, content_hash, server_updated_at,
+  replay_gain_track_db, replay_gain_album_db, replay_gain_peak, content_hash, server_updated_at,
   server_created_at, deleted, synced_at, raw_json
-) VALUES (
-  ?1, ?2, ?3, ?4, ?5, ?6, ?7, ?8, ?9, ?10, ?11, ?12, ?13, ?14, ?15, ?16, ?17,
-  ?18, ?19, ?20, ?21, ?22, ?23, ?24, ?25, ?26, ?27, ?28, ?29, ?30, ?31, ?32,
-  ?33, ?34, ?35
-)
-ON CONFLICT(server_id, id) DO UPDATE SET
-  title                = excluded.title,
-  title_sort           = excluded.title_sort,
-  artist               = excluded.artist,
-  artist_id            = excluded.artist_id,
-  album                = excluded.album,
-  album_id             = excluded.album_id,
-  album_artist         = excluded.album_artist,
-  duration_sec         = excluded.duration_sec,
-  track_number         = excluded.track_number,
-  disc_number          = excluded.disc_number,
-  year                 = excluded.year,
-  genre                = excluded.genre,
-  suffix               = excluded.suffix,
-  bit_rate             = excluded.bit_rate,
-  size_bytes           = excluded.size_bytes,
-  cover_art_id         = excluded.cover_art_id,
-  starred_at           = excluded.starred_at,
-  user_rating          = excluded.user_rating,
-  play_count           = excluded.play_count,
-  played_at            = excluded.played_at,
-  server_path          = excluded.server_path,
-  library_id           = excluded.library_id,
-  isrc                 = excluded.isrc,
-  mbid_recording       = excluded.mbid_recording,
-  bpm                  = excluded.bpm,
-  replay_gain_track_db = excluded.replay_gain_track_db,
-  replay_gain_album_db = excluded.replay_gain_album_db,
-  -- E2: never let a sync (which passes NULL content_hash) clobber the
-  -- playback-derived md5_16kb written via library_patch_track / the analysis
-  -- bridge. A non-empty incoming hash still wins.
-  content_hash         = COALESCE(NULLIF(excluded.content_hash, ''), track.content_hash),
-  server_updated_at    = excluded.server_updated_at,
-  server_created_at    = excluded.server_created_at,
-  deleted              = excluded.deleted,
-  synced_at            = excluded.synced_at,
-  raw_json             = excluded.raw_json
-"#;
-
-const UPSERT_INITIAL_RESYNC_SQL: &str = r#"
-INSERT INTO track (
-  server_id, id, title, title_sort, artist, artist_id, album, album_id,
-  album_artist, duration_sec, track_number, disc_number, year, genre, suffix,
-  bit_rate, size_bytes, cover_art_id, starred_at, user_rating, play_count,
-  played_at, server_path, library_id, isrc, mbid_recording, bpm,
-  replay_gain_track_db, replay_gain_album_db, content_hash, server_updated_at,
-  server_created_at, deleted, synced_at, raw_json, resync_gen
 ) VALUES (
   ?1, ?2, ?3, ?4, ?5, ?6, ?7, ?8, ?9, ?10, ?11, ?12, ?13, ?14, ?15, ?16, ?17,
   ?18, ?19, ?20, ?21, ?22, ?23, ?24, ?25, ?26, ?27, ?28, ?29, ?30, ?31, ?32,
@@ -835,6 +788,60 @@ ON CONFLICT(server_id, id) DO UPDATE SET
   bpm                  = excluded.bpm,
   replay_gain_track_db = excluded.replay_gain_track_db,
   replay_gain_album_db = excluded.replay_gain_album_db,
+  replay_gain_peak     = excluded.replay_gain_peak,
+  -- E2: never let a sync (which passes NULL content_hash) clobber the
+  -- playback-derived md5_16kb written via library_patch_track / the analysis
+  -- bridge. A non-empty incoming hash still wins.
+  content_hash         = COALESCE(NULLIF(excluded.content_hash, ''), track.content_hash),
+  server_updated_at    = excluded.server_updated_at,
+  server_created_at    = excluded.server_created_at,
+  deleted              = excluded.deleted,
+  synced_at            = excluded.synced_at,
+  raw_json             = excluded.raw_json
+"#;
+
+const UPSERT_INITIAL_RESYNC_SQL: &str = r#"
+INSERT INTO track (
+  server_id, id, title, title_sort, artist, artist_id, album, album_id,
+  album_artist, duration_sec, track_number, disc_number, year, genre, suffix,
+  bit_rate, size_bytes, cover_art_id, starred_at, user_rating, play_count,
+  played_at, server_path, library_id, isrc, mbid_recording, bpm,
+  replay_gain_track_db, replay_gain_album_db, replay_gain_peak, content_hash, server_updated_at,
+  server_created_at, deleted, synced_at, raw_json, resync_gen
+) VALUES (
+  ?1, ?2, ?3, ?4, ?5, ?6, ?7, ?8, ?9, ?10, ?11, ?12, ?13, ?14, ?15, ?16, ?17,
+  ?18, ?19, ?20, ?21, ?22, ?23, ?24, ?25, ?26, ?27, ?28, ?29, ?30, ?31, ?32,
+  ?33, ?34, ?35, ?36, ?37
+)
+ON CONFLICT(server_id, id) DO UPDATE SET
+  title                = excluded.title,
+  title_sort           = excluded.title_sort,
+  artist               = excluded.artist,
+  artist_id            = excluded.artist_id,
+  album                = excluded.album,
+  album_id             = excluded.album_id,
+  album_artist         = excluded.album_artist,
+  duration_sec         = excluded.duration_sec,
+  track_number         = excluded.track_number,
+  disc_number          = excluded.disc_number,
+  year                 = excluded.year,
+  genre                = excluded.genre,
+  suffix               = excluded.suffix,
+  bit_rate             = excluded.bit_rate,
+  size_bytes           = excluded.size_bytes,
+  cover_art_id         = excluded.cover_art_id,
+  starred_at           = excluded.starred_at,
+  user_rating          = excluded.user_rating,
+  play_count           = excluded.play_count,
+  played_at            = excluded.played_at,
+  server_path          = excluded.server_path,
+  library_id           = excluded.library_id,
+  isrc                 = excluded.isrc,
+  mbid_recording       = excluded.mbid_recording,
+  bpm                  = excluded.bpm,
+  replay_gain_track_db = excluded.replay_gain_track_db,
+  replay_gain_album_db = excluded.replay_gain_album_db,
+  replay_gain_peak     = excluded.replay_gain_peak,
   content_hash         = COALESCE(NULLIF(excluded.content_hash, ''), track.content_hash),
   server_updated_at    = excluded.server_updated_at,
   server_created_at    = excluded.server_created_at,
@@ -887,6 +894,7 @@ mod tests {
             bpm: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             content_hash: Some("hash-abc".into()),
             server_updated_at: Some(1_700_000_000),
             server_created_at: Some(1_699_000_000),

src-tauri/crates/psysonic-library/src/search.rs

@@ -356,6 +356,7 @@ mod tests {
             bpm: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             content_hash: None,
             server_updated_at: None,
             server_created_at: None,

src-tauri/crates/psysonic-library/src/store.rs

@@ -12,11 +12,14 @@ use tauri::Manager;
 ///
 /// Migration checklist (wiring, data backfill, open/swap path):
 /// psysonic-workdocs `ai/agent-rules/08-library-db-migrations.md`.
-pub const LIBRARY_DB_SCHEMA_VERSION: i64 = 14;
+pub const LIBRARY_DB_SCHEMA_VERSION: i64 = 15;
 
 /// One-time data repair after migration 014 (`artist.name_sort`).
 pub(crate) const ARTIST_NAME_SORT_RECONCILE_ID: &str = "artist_name_sort_reconcile_v1";
 
+/// One-time backfill after migration 015 (`track.replay_gain_peak`).
+pub(crate) const REPLAY_GAIN_PEAK_RECONCILE_ID: &str = "replay_gain_peak_reconcile_v1";
+
 /// Lowest applied schema version the current code can advance from purely
 /// additively. If a DB carries a version below this, the breaking-bump hook
 /// fires (spec §5.7 / P22): the library is treated as incompatible, must be
@@ -38,6 +41,8 @@ pub(crate) const MIGRATION_013_ARTIST_ARTWORK_LOOKUP: &str =
     include_str!("../migrations/013_artist_artwork_lookup.sql");
 pub(crate) const MIGRATION_014_ARTIST_NAME_SORT: &str =
     include_str!("../migrations/014_artist_name_sort.sql");
+pub(crate) const MIGRATION_015_REPLAY_GAIN_PEAK: &str =
+    include_str!("../migrations/015_replay_gain_peak.sql");
 
 /// Embedded migrations. Ordered ascending by `version`; the runner sorts
 /// defensively before applying so the source order can stay readable.
@@ -46,6 +51,7 @@ const MIGRATIONS: &[(i64, &str)] = &[
     (12, MIGRATION_012_TRACK_GENRE_LEGACY),
     (13, MIGRATION_013_ARTIST_ARTWORK_LOOKUP),
     (14, MIGRATION_014_ARTIST_NAME_SORT),
+    (15, MIGRATION_015_REPLAY_GAIN_PEAK),
 ];
 
 /// Idempotent repair — also runs after the migration runner on every open so
@@ -589,6 +595,7 @@ fn open_database_connections(db_path: &Path) -> rusqlite::Result<(Connection, Co
 fn prepare_write_connection_for_open(conn: &Connection) -> rusqlite::Result<()> {
     run_migrations(conn)?;
     maybe_reconcile_artist_name_sort(conn)?;
+    maybe_reconcile_replay_gain_peak(conn)?;
     ensure_genre_tags_schema(conn)?;
     checkpoint_wal_conn(conn, "open")?;
     Ok(())
@@ -721,6 +728,68 @@ fn repair_artist_name_sort_keys(conn: &Connection) -> rusqlite::Result<()> {
     Ok(())
 }
 
+fn replay_gain_peak_column_exists(conn: &Connection) -> rusqlite::Result<bool> {
+    let column_exists: i64 = conn
+        .query_row(
+            "SELECT COUNT(*) FROM pragma_table_info('track') WHERE name = 'replay_gain_peak'",
+            [],
+            |row| row.get(0),
+        )
+        .unwrap_or(0);
+    Ok(column_exists > 0)
+}
+
+fn replay_gain_peak_reconcile_completed(conn: &Connection) -> rusqlite::Result<bool> {
+    let completed: Option<Option<i64>> = conn
+        .query_row(
+            "SELECT completed_at FROM library_data_migration WHERE id = ?1",
+            params![REPLAY_GAIN_PEAK_RECONCILE_ID],
+            |row| row.get(0),
+        )
+        .optional()?;
+    Ok(completed.flatten().is_some())
+}
+
+fn mark_replay_gain_peak_reconcile_completed(conn: &Connection) -> rusqlite::Result<()> {
+    conn.execute(
+        "INSERT INTO library_data_migration (id, cursor_rowid, started_at, completed_at) \
+         VALUES (?1, 0, strftime('%s','now'), strftime('%s','now')) \
+         ON CONFLICT(id) DO UPDATE SET completed_at = excluded.completed_at",
+        params![REPLAY_GAIN_PEAK_RECONCILE_ID],
+    )?;
+    Ok(())
+}
+
+/// One-time backfill after schema 015 — project peak from stored `raw_json`.
+fn repair_replay_gain_peak_from_raw_json(conn: &Connection) -> rusqlite::Result<()> {
+    conn.execute(
+        "UPDATE track SET replay_gain_peak = json_extract(raw_json, '$.replayGain.trackPeak') \
+         WHERE replay_gain_peak IS NULL \
+           AND json_type(json_extract(raw_json, '$.replayGain.trackPeak')) = 'real'",
+        [],
+    )?;
+    conn.execute(
+        "UPDATE track SET replay_gain_peak = json_extract(raw_json, '$.rgTrackPeak') \
+         WHERE replay_gain_peak IS NULL \
+           AND json_type(json_extract(raw_json, '$.rgTrackPeak')) = 'real'",
+        [],
+    )?;
+    Ok(())
+}
+
+/// One-time reconcile after schema 015 — not on every open.
+fn maybe_reconcile_replay_gain_peak(conn: &Connection) -> rusqlite::Result<()> {
+    if !replay_gain_peak_column_exists(conn)? {
+        return Ok(());
+    }
+    if replay_gain_peak_reconcile_completed(conn)? {
+        return Ok(());
+    }
+    repair_replay_gain_peak_from_raw_json(conn)?;
+    mark_replay_gain_peak_reconcile_completed(conn)?;
+    Ok(())
+}
+
 fn run_migrations(conn: &Connection) -> rusqlite::Result<MigrationOutcome> {
     run_migrations_with(
         conn,

src-tauri/crates/psysonic-library/src/sync/delta.rs

@@ -639,6 +639,7 @@ mod tests {
                 bpm: None,
                 replay_gain_track_db: None,
                 replay_gain_album_db: None,
+                replay_gain_peak: None,
                 content_hash: None,
                 server_updated_at: Some(server_updated_at),
                 server_created_at: None,

src-tauri/crates/psysonic-library/src/sync/initial.rs

@@ -2265,6 +2265,7 @@ mod tests {
             bpm: None,
             replay_gain_track_db: None,
             replay_gain_album_db: None,
+            replay_gain_peak: None,
             content_hash: None,
             server_updated_at: None,
             server_created_at: None,
@@ -2306,6 +2307,7 @@ mod tests {
                     bpm: None,
                     replay_gain_track_db: None,
                     replay_gain_album_db: None,
+                    replay_gain_peak: None,
                     content_hash: None,
                     server_updated_at: None,
                     server_created_at: None,

src-tauri/crates/psysonic-library/src/sync/mapping.rs

@@ -70,6 +70,10 @@ pub fn subsonic_song_to_track_row(
             .get("replayGain")
             .and_then(|rg| rg.get("albumGain"))
             .and_then(|v| v.as_f64()),
+        replay_gain_peak: raw_value
+            .get("replayGain")
+            .and_then(|rg| rg.get("trackPeak"))
+            .and_then(|v| v.as_f64()),
         content_hash: None,
         server_updated_at: None,
         server_created_at: None,
@@ -134,6 +138,7 @@ pub fn navidrome_song_to_track_row(
         bpm: raw.get("bpm").and_then(|v| v.as_i64()),
         replay_gain_track_db: raw.get("rgTrackGain").and_then(|v| v.as_f64()),
         replay_gain_album_db: raw.get("rgAlbumGain").and_then(|v| v.as_f64()),
+        replay_gain_peak: raw.get("rgTrackPeak").and_then(|v| v.as_f64()),
         content_hash: None,
         server_updated_at,
         server_created_at: raw
@@ -258,7 +263,7 @@ mod tests {
             "track": 3,
             "year": 2024,
             "musicBrainzId": "mb-1",
-            "replayGain": { "trackGain": -1.2, "albumGain": -0.8 }
+            "replayGain": { "trackGain": -1.2, "albumGain": -0.8, "trackPeak": 0.91 }
         });
         let song: Song = serde_json::from_value(raw.clone()).unwrap();
         let row = subsonic_song_to_track_row("s1", &song, &raw, 1_000, Some("lib-fb"));
@@ -268,6 +273,7 @@ mod tests {
         assert_eq!(row.mbid_recording.as_deref(), Some("mb-1"));
         assert_eq!(row.replay_gain_track_db, Some(-1.2));
         assert_eq!(row.replay_gain_album_db, Some(-0.8));
+        assert_eq!(row.replay_gain_peak, Some(0.91));
         // Fallback library_id kicks in when the song didn't ship one.
         assert_eq!(row.library_id.as_deref(), Some("lib-fb"));
         assert!(row.raw_json.contains("replayGain"));

src-tauri/crates/psysonic-library/src/sync/tombstone.rs

@@ -271,6 +271,7 @@ mod tests {
                 bpm: None,
                 replay_gain_track_db: None,
                 replay_gain_album_db: None,
+                replay_gain_peak: None,
                 content_hash: None,
                 server_updated_at: None,
                 server_created_at: None,