fix(subsonic): update the playlist changed timestamp when renaming a smart playlist (#6082)

`buildPlaylist` reported `evaluated_at` as `changed` for smart playlists, so a
rename or comment edit was invisible to clients until the next evaluation. A
never-evaluated smart playlist also reported the current time on every call,
which never settled.

Report `updated_at` for every playlist. `refreshCounters` now syncs the stamp it
writes back onto the model, and `refreshSmartPlaylist` reuses it for
`evaluated_at`. `changed` therefore still equals the evaluation time for a
just-evaluated playlist, and `validUntil` stays anchored to it.

Original Subsonic always bumps `changed` on any playlist update, so this also
aligns the behavior with upstream.

persistence/playlist_repository.go

@@ -316,11 +316,12 @@ func (r *playlistRepository) refreshCounters(pls *model.Playlist) error {
 	}
 
 	// Update playlist's total duration, size and count
+	now := time.Now()
 	upd := Update("playlist").
 		Set("duration", res.Duration).
 		Set("size", res.Size).
 		Set("song_count", res.Count).
-		Set("updated_at", time.Now()).
+		Set("updated_at", now).
 		Where(Eq{"id": pls.ID})
 	_, err = r.executeSQL(upd)
 	if err != nil {
@@ -329,6 +330,7 @@ func (r *playlistRepository) refreshCounters(pls *model.Playlist) error {
 	pls.SongCount = int(res.Count)
 	pls.Duration = res.Duration
 	pls.Size = int64(res.Size)
+	pls.UpdatedAt = now
 	return nil
 }
 

persistence/smart_playlist_repository.go

@@ -58,7 +58,8 @@ func (r *playlistRepository) refreshSmartPlaylist(pls *model.Playlist) bool {
 		return false
 	}
 
-	now := time.Now()
+	// Reuse the stamp refreshCounters just wrote, so evaluated_at and updated_at agree
+	now := pls.UpdatedAt
 	updSql := Update(r.tableName).Set("evaluated_at", now).Where(Eq{"id": pls.ID})
 	if _, err = r.executeSQL(updSql); err != nil {
 		log.Error(r.ctx, "Error updating smart playlist", "playlist", pls.Name, "id", pls.ID, err)

persistence/smart_playlist_repository_test.go

@@ -45,6 +45,23 @@ var _ = Describe("PlaylistRepository - Smart Playlists", func() {
 			})
 		})
 
+		Context("after an evaluation", func() {
+			It("stamps updated_at and evaluated_at with the same instant", func() {
+				newPls := model.Playlist{Name: "Evaluated", OwnerID: "userid", Rules: rules}
+				Expect(repo.Put(&newPls)).To(Succeed())
+				DeferCleanup(func() { _ = repo.Delete(newPls.ID) })
+
+				refreshed, err := repo.GetWithTracks(newPls.ID, true, false)
+				Expect(err).ToNot(HaveOccurred())
+
+				stored, err := repo.Get(newPls.ID)
+				Expect(err).ToNot(HaveOccurred())
+				Expect(stored.EvaluatedAt).ToNot(BeNil())
+				Expect(stored.UpdatedAt).To(BeTemporally("==", *stored.EvaluatedAt))
+				Expect(refreshed.UpdatedAt).To(BeTemporally("==", stored.UpdatedAt))
+			})
+		})
+
 		Context("invalid rules", func() {
 			It("fails to Put it in the DB", func() {
 				rules = &criteria.Criteria{

server/subsonic/playlists.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
-	"time"
 
 	"github.com/navidrome/navidrome/conf"
 	"github.com/navidrome/navidrome/log"
@@ -133,15 +132,7 @@ func (api *Router) buildPlaylist(ctx context.Context, p model.Playlist) response
 	pls.SongCount = int32(p.SongCount)
 	pls.Duration = int32(p.Duration)
 	pls.Created = p.CreatedAt
-	if p.IsSmartPlaylist() {
-		if p.EvaluatedAt != nil {
-			pls.Changed = *p.EvaluatedAt
-		} else {
-			pls.Changed = time.Now()
-		}
-	} else {
-		pls.Changed = p.UpdatedAt
-	}
+	pls.Changed = p.UpdatedAt
 
 	player, ok := request.PlayerFrom(ctx)
 	if ok && isClientInList(conf.Server.Subsonic.MinimalClients, player.Client) {

server/subsonic/playlists_test.go

@@ -220,7 +220,7 @@ var _ = Describe("buildPlaylist", func() {
 				Expect(result.SongCount).To(Equal(int32(10)))
 				Expect(result.Duration).To(Equal(int32(600)))
 				Expect(result.Created).To(Equal(playlist.CreatedAt))
-				Expect(result.Changed).To(Equal(evaluatedAt))
+				Expect(result.Changed).To(Equal(playlist.UpdatedAt))
 
 				// These should not be set
 				Expect(result.Comment).To(BeEmpty())
@@ -245,7 +245,7 @@ var _ = Describe("buildPlaylist", func() {
 				Expect(result.SongCount).To(Equal(int32(10)))
 				Expect(result.Duration).To(Equal(int32(600)))
 				Expect(result.Created).To(Equal(playlist.CreatedAt))
-				Expect(result.Changed).To(Equal(*playlist.EvaluatedAt))
+				Expect(result.Changed).To(Equal(playlist.UpdatedAt))
 				Expect(result.Comment).To(Equal("Test comment"))
 				Expect(result.Owner).To(Equal("admin"))
 				Expect(result.Public).To(BeTrue())
@@ -271,6 +271,21 @@ var _ = Describe("buildPlaylist", func() {
 			})
 		})
 
+		Context("when it was never evaluated", func() {
+			BeforeEach(func() {
+				playlist.EvaluatedAt = nil
+				player := model.Player{Client: "regular-client"}
+				ctx = request.WithPlayer(ctx, player)
+			})
+
+			It("omits validUntil but still reports changed", func() {
+				result := router.buildPlaylist(ctx, playlist)
+
+				Expect(result.ValidUntil).To(BeNil())
+				Expect(result.Changed).To(Equal(playlist.UpdatedAt))
+			})
+		})
+
 		Context("with a per-playlist refreshDelay", func() {
 			BeforeEach(func() {
 				playlist.Rules.RefreshDelay = 24 * time.Hour