From 929e7193b4c11f01cab6aa7527431f6b44234fe3 Mon Sep 17 00:00:00 2001
From: Deluan <deluan@navidrome.org>
Date: Tue, 17 Feb 2026 09:00:23 -0500
Subject: [PATCH] refactor: use natural.Compare directly instead of wrapper

---
 db/db.go                       |   4 +-
 utils/str/natural_sort.go      |  16 ------
 utils/str/natural_sort_test.go | 101 ---------------------------------
 3 files changed, 2 insertions(+), 119 deletions(-)
 delete mode 100644 utils/str/natural_sort.go
 delete mode 100644 utils/str/natural_sort_test.go

diff --git a/db/db.go b/db/db.go
index e69661697..ff852c740 100644
--- a/db/db.go
+++ b/db/db.go
@@ -7,13 +7,13 @@ import (
 	"fmt"
 	"runtime"
 
+	"github.com/maruel/natural"
 	"github.com/mattn/go-sqlite3"
 	"github.com/navidrome/navidrome/conf"
 	_ "github.com/navidrome/navidrome/db/migrations"
 	"github.com/navidrome/navidrome/log"
 	"github.com/navidrome/navidrome/utils/hasher"
 	"github.com/navidrome/navidrome/utils/singleton"
-	"github.com/navidrome/navidrome/utils/str"
 	"github.com/pressly/goose/v3"
 )
 
@@ -35,7 +35,7 @@ func Db() *sql.DB {
 				if err := conn.RegisterFunc("SEEDEDRAND", hasher.HashFunc(), false); err != nil {
 					return err
 				}
-				return conn.RegisterCollation("NATURALSORT", str.NaturalSortCompare)
+				return conn.RegisterCollation("NATURALSORT", natural.Compare)
 			},
 		})
 		Path = conf.Server.DbPath
diff --git a/utils/str/natural_sort.go b/utils/str/natural_sort.go
deleted file mode 100644
index 281114e1f..000000000
--- a/utils/str/natural_sort.go
+++ /dev/null
@@ -1,16 +0,0 @@
-package str
-
-import (
-	"strings"
-
-	"github.com/maruel/natural"
-)
-
-// NaturalSortCompare compares two strings using natural sort ordering,
-// where embedded numeric sequences are compared as numbers rather than
-// lexicographically. For example, "track2" < "track10" (unlike lexicographic
-// ordering which gives "track10" < "track2"). The comparison is also
-// case-insensitive.
-func NaturalSortCompare(a, b string) int {
-	return natural.Compare(strings.ToLower(a), strings.ToLower(b))
-}
diff --git a/utils/str/natural_sort_test.go b/utils/str/natural_sort_test.go
deleted file mode 100644
index 514c79b69..000000000
--- a/utils/str/natural_sort_test.go
+++ /dev/null
@@ -1,101 +0,0 @@
-package str_test
-
-import (
-	"testing"
-
-	"github.com/navidrome/navidrome/utils/str"
-)
-
-func TestNaturalSortCompare(t *testing.T) {
-	tests := []struct {
-		name string
-		a, b string
-		want int // -1, 0, or 1
-	}{
-		// Basic string comparison
-		{"equal strings", "abc", "abc", 0},
-		{"less than", "abc", "abd", -1},
-		{"greater than", "abd", "abc", 1},
-
-		// Case insensitive
-		{"case insensitive equal", "ABC", "abc", 0},
-		{"case insensitive less", "ABC", "abd", -1},
-		{"case insensitive mixed", "aBc", "AbC", 0},
-
-		// Numeric ordering
-		{"single digit order", "track1", "track2", -1},
-		{"natural sort 2 vs 10", "track2", "track10", -1},
-		{"natural sort 9 vs 10", "track9", "track10", -1},
-		{"natural sort 10 vs 2", "track10", "track2", 1},
-		{"natural sort 1 vs 100", "track1", "track100", -1},
-
-		// Album numbering (main use case from issue)
-		{"album numbers 1 vs 2", "Bravo Hits 1", "Bravo Hits 2", -1},
-		{"album numbers 2 vs 10", "Bravo Hits 2", "Bravo Hits 10", -1},
-		{"album numbers 10 vs 100", "Bravo Hits 10", "Bravo Hits 100", -1},
-		{"album numbers 9 vs 10", "Bravo Hits 9", "Bravo Hits 10", -1},
-		{"album numbers equal", "Bravo Hits 10", "Bravo Hits 10", 0},
-		{"album numbers 99 vs 100", "Bravo Hits 99", "Bravo Hits 100", -1},
-		{"album numbers 100 vs 101", "Bravo Hits 100", "Bravo Hits 101", -1},
-
-		// Pure numeric strings
-		{"pure number 1 vs 2", "1", "2", -1},
-		{"pure number 2 vs 10", "2", "10", -1},
-		{"pure number 10 vs 9", "10", "9", 1},
-		{"pure number equal", "42", "42", 0},
-
-		// Multiple numeric sequences
-		{"multi number 1.2 vs 1.10", "file1.2", "file1.10", -1},
-		{"multi number 2.1 vs 10.1", "file2.1", "file10.1", -1},
-
-		// Empty strings
-		{"both empty", "", "", 0},
-		{"empty vs non-empty", "", "a", -1},
-		{"non-empty vs empty", "a", "", 1},
-
-		// Edge cases
-		{"same prefix different length", "abc", "abcd", -1},
-		{"numbers at beginning", "10abc", "9abc", 1},
-		{"numbers at end", "abc10", "abc9", 1},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			got := str.NaturalSortCompare(tt.a, tt.b)
-			// Normalize to -1, 0, 1 for comparison
-			gotNorm := normalize(got)
-			if gotNorm != tt.want {
-				t.Errorf("NaturalSortCompare(%q, %q) = %d (normalized: %d), want %d", tt.a, tt.b, got, gotNorm, tt.want)
-			}
-		})
-	}
-}
-
-func TestNaturalSortCompare_Symmetry(t *testing.T) {
-	pairs := [][2]string{
-		{"track2", "track10"},
-		{"abc", "abd"},
-		{"Bravo Hits 9", "Bravo Hits 10"},
-		{"1", "2"},
-		{"file1.2", "file1.10"},
-	}
-
-	for _, pair := range pairs {
-		a, b := pair[0], pair[1]
-		ab := str.NaturalSortCompare(a, b)
-		ba := str.NaturalSortCompare(b, a)
-		if normalize(ab) != -normalize(ba) {
-			t.Errorf("Symmetry violated: Compare(%q,%q)=%d but Compare(%q,%q)=%d", a, b, ab, b, a, ba)
-		}
-	}
-}
-
-func normalize(v int) int {
-	if v < 0 {
-		return -1
-	}
-	if v > 0 {
-		return 1
-	}
-	return 0
-}