From cb0a6cedd6c445d8040df3ac01fe69d06ca27b75 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Deluan=20Quint=C3=A3o?= <deluan@navidrome.org>
Date: Tue, 25 Aug 2026 10:58:58 -0400
Subject: [PATCH] fix(scanner): keep album tag order from the files instead of
 alphabetical (#5872)

Album-level tags were ordered by frequency and then alphabetically by value.
Album.Genre is just the first genre in that list, so any album whose genres tie
on frequency, which is the normal case, displayed the alphabetically first genre
rather than the first one in the file. A file tagged
"Native American New Age; Indigenous American Traditional Music; Ambient"
showed up as "Ambient".

Break frequency ties on order of appearance instead. This affects all
album-level tags, so mood tagged "Happy; Chill" now keeps that order too.
MediaFiles.ToAlbum already sorts the files by path before flattening their tags,
so the aggregated order stays deterministic across scans.

Only album genre was affected; media_file tags already preserved file order.
---
 model/mediafile_test.go | 6 +++---
 model/tag.go            | 8 ++++++--
 model/tag_test.go       | 4 ++--
 3 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/model/mediafile_test.go b/model/mediafile_test.go
index 097e3ca54..9ca3489bb 100644
--- a/model/mediafile_test.go
+++ b/model/mediafile_test.go
@@ -218,11 +218,11 @@ var _ = Describe("MediaFiles", func() {
 							{Tags: Tags{"genre": []string{"Alternative", "Rock"}}},
 						}
 					})
-					It("sets the correct Genre, sorted by frequency, then alphabetically", func() {
+					It("sets the correct Genre, sorted by frequency, then by order of appearance", func() {
 						album := mfs.ToAlbum()
 						Expect(album.Tags).To(HaveLen(2))
-						Expect(album.Tags).To(HaveKeyWithValue(TagGenre, []string{"Rock", "Alternative", "Punk"}))
-						Expect(album.Tags).To(HaveKeyWithValue(TagMood, []string{"Chill", "Happy"}))
+						Expect(album.Tags).To(HaveKeyWithValue(TagGenre, []string{"Rock", "Punk", "Alternative"}))
+						Expect(album.Tags).To(HaveKeyWithValue(TagMood, []string{"Happy", "Chill"}))
 					})
 				})
 				When("we have tags with mismatching case", func() {
diff --git a/model/tag.go b/model/tag.go
index bb4fce181..234cfb359 100644
--- a/model/tag.go
+++ b/model/tag.go
@@ -24,13 +24,17 @@ type TagList []Tag
 func (l TagList) GroupByFrequency() Tags {
 	grouped := map[string]map[string]int{}
 	values := map[string]string{}
-	for _, t := range l {
+	firstSeen := map[string]int{}
+	for i, t := range l {
 		if m, ok := grouped[string(t.TagName)]; !ok {
 			grouped[string(t.TagName)] = map[string]int{t.ID: 1}
 		} else {
 			m[t.ID]++
 		}
 		values[t.ID] = t.TagValue
+		if _, ok := firstSeen[t.ID]; !ok {
+			firstSeen[t.ID] = i
+		}
 	}
 
 	tags := Tags{}
@@ -42,7 +46,7 @@ func (l TagList) GroupByFrequency() Tags {
 		slices.SortFunc(idList, func(a, b string) int {
 			return cmp.Or(
 				cmp.Compare(counts[b], counts[a]),
-				cmp.Compare(values[a], values[b]),
+				cmp.Compare(firstSeen[a], firstSeen[b]),
 			)
 		})
 		tags[TagName(name)] = slice.Map(idList, func(id string) string { return values[id] })
diff --git a/model/tag_test.go b/model/tag_test.go
index c01aa0b4c..4dc99019b 100644
--- a/model/tag_test.go
+++ b/model/tag_test.go
@@ -93,7 +93,7 @@ var _ = Describe("Tag", func() {
 				Expect(groupedTags).To(HaveKeyWithValue(TagName("artist"), []string{"The Beatles", "The Rolling Stones"}))
 			})
 
-			It("should sort tags by name when frequency is the same", func() {
+			It("should keep the order the values appeared in when frequency is the same", func() {
 				tagList := TagList{
 					NewTag("genre", "Jazz"),
 					NewTag("genre", "Rock"),
@@ -103,7 +103,7 @@ var _ = Describe("Tag", func() {
 
 				groupedTags := tagList.GroupByFrequency()
 
-				Expect(groupedTags).To(HaveKeyWithValue(TagName("genre"), []string{"Alternative", "Jazz", "Pop", "Rock"}))
+				Expect(groupedTags).To(HaveKeyWithValue(TagName("genre"), []string{"Jazz", "Rock", "Alternative", "Pop"}))
 			})
 			It("should normalize casing", func() {
 				tagList := TagList{