diff --git a/utils/.DS_Store b/utils/.DS_Store
new file mode 100644
index 0000000..e1dd56d
Binary files /dev/null and b/utils/.DS_Store differ
diff --git a/utils/layout_test.go b/utils/layout_test.go
new file mode 100644
index 0000000..75ca6af
--- /dev/null
+++ b/utils/layout_test.go
@@ -0,0 +1,171 @@
+package utils
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestSaveLayout(t *testing.T) {
+	tests := []struct {
+		name     string
+		props    SaveLayoutProps
+		expected string
+	}{
+		{
+			name: "Basic_placeholders",
+			props: SaveLayoutProps{
+				Track: map[string]interface{}{
+					"TRACK_NUMBER": 1,
+					"TITLE":        "Song Title",
+				},
+				Album: map[string]interface{}{
+					"ARTIST":    "Artist Name",
+					"ALB_TITLE": "Album Name",
+				},
+				Path:                 "{ARTIST}/{ALB_TITLE}/{TRACK_NUMBER} - {TITLE}.mp3",
+				MinimumIntegerDigits: 2,
+				TrackNumber:          false,
+			},
+			expected: "Artist Name/Album Name/01 - Song Title.mp3",
+		},
+		{
+			name: "Missing_keys",
+			props: SaveLayoutProps{
+				Track: map[string]interface{}{
+					"TITLE": "Song Title",
+				},
+				Album: map[string]interface{}{
+					"ARTIST": "Artist Name",
+				},
+				Path:                 "{ARTIST}/{ALB_TITLE}/{TRACK_NUMBER} - {TITLE}.mp3",
+				MinimumIntegerDigits: 2,
+				TrackNumber:          false,
+			},
+			expected: "Artist Name/ - Song Title.mp3",
+		},
+		{
+			name: "Special_characters",
+			props: SaveLayoutProps{
+				Track: map[string]interface{}{
+					"TRACK_NUMBER": 1,
+					"TITLE":        "Song:Title*With|Special<>Chars?",
+				},
+				Album: map[string]interface{}{
+					"ARTIST":    "Artist/Name\\With\"Special:Chars",
+					"ALB_TITLE": "Album|Name*With?Special<>Chars",
+				},
+				Path:                 "{ARTIST}/{ALB_TITLE}/{TRACK_NUMBER} - {TITLE}.mp3",
+				MinimumIntegerDigits: 2,
+				TrackNumber:          false,
+			},
+			expected: "Artist_Name_With_Special_Chars/Album_Name_With_Special__Chars/01 - Song_Title_With_Special__Chars_.mp3",
+		},
+		{
+			name: "TrackNumber_flag_true",
+			props: SaveLayoutProps{
+				Track: map[string]interface{}{
+					"TRACK_NUMBER": 5,
+					"TITLE":        "Song Title",
+				},
+				Album: map[string]interface{}{
+					"ARTIST":    "Artist Name",
+					"ALB_TITLE": "Album Name",
+				},
+				Path:                 "{ARTIST}/{ALB_TITLE}/{TITLE}.mp3",
+				MinimumIntegerDigits: 2,
+				TrackNumber:          true,
+			},
+			expected: "Artist Name/Album Name/05 - Song Title.mp3",
+		},
+		{
+			name: "Relative_path",
+			props: SaveLayoutProps{
+				Track: map[string]interface{}{
+					"TRACK_NUMBER": 3,
+					"TITLE":        "Song Title",
+				},
+				Album: map[string]interface{}{
+					"ARTIST":    "Artist Name",
+					"ALB_TITLE": "Album Name",
+				},
+				Path:                 "{ARTIST}/{TITLE}.mp3",
+				MinimumIntegerDigits: 2,
+				TrackNumber:          true,
+			},
+			expected: "Artist Name/03 - Song Title.mp3",
+		},
+		{
+			name: "No_placeholders",
+			props: SaveLayoutProps{
+				Track:                nil,
+				Album:                nil,
+				Path:                 "static/path/filename.mp3",
+				MinimumIntegerDigits: 2,
+				TrackNumber:          false,
+			},
+			expected: "static/path/filename.mp3",
+		},
+		{
+			name: "Invalid_track_number",
+			props: SaveLayoutProps{
+				Track: map[string]interface{}{
+					"TRACK_NUMBER": "invalid",
+					"TITLE":        "Song Title",
+				},
+				Album: map[string]interface{}{
+					"ARTIST":    "Artist Name",
+					"ALB_TITLE": "Album Name",
+				},
+				Path:                 "{ARTIST}/{ALB_TITLE}/{TRACK_NUMBER} - {TITLE}.mp3",
+				MinimumIntegerDigits: 2,
+				TrackNumber:          false,
+			},
+			expected: "Artist Name/Album Name/00 - Song Title.mp3",
+		},
+		{
+			name: "Disc_number_adjustment",
+			props: SaveLayoutProps{
+				Track: map[string]interface{}{
+					"TRACK_NUMBER": 1,
+					"TITLE":        "Song Title",
+					"DISK_NUMBER":  2,
+				},
+				Album: map[string]interface{}{
+					"ARTIST":      "Artist Name",
+					"ALB_TITLE":   "Album Name",
+					"NUMBER_DISK": 3,
+				},
+				Path:                 "{ARTIST}/{ALB_TITLE}/{TRACK_NUMBER} - {TITLE}.mp3",
+				MinimumIntegerDigits: 2,
+				TrackNumber:          false,
+			},
+			expected: "Artist Name/Album Name (Disc 02)/01 - Song Title.mp3",
+		},
+		{
+			name: "Nested_key_access",
+			props: SaveLayoutProps{
+				Track: map[string]interface{}{
+					"INFO": map[string]interface{}{
+						"TRACK_NUMBER": 4,
+					},
+					"TITLE": "Song Title",
+				},
+				Album: map[string]interface{}{
+					"ARTIST": "Artist Name",
+				},
+				Path:                 "{ARTIST}/{INFO.TRACK_NUMBER} - {TITLE}.mp3",
+				MinimumIntegerDigits: 2,
+				TrackNumber:          false,
+			},
+			expected: "Artist Name/04 - Song Title.mp3",
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			result := SaveLayout(test.props)
+			assert.Equal(t, test.expected, result, "Test '%s' failed", test.name)
+		})
+	}
+}