feat: format multi-artist credits

internal/provider/beatport/client.go

@@ -507,7 +507,8 @@ func (c *Client) normalizeRelease(raw map[string]any, tracks []any) map[string]a
 
 func (c *Client) normalizeTrack(raw map[string]any) map[string]any {
 	release := mapAny(raw["release"])
-	artistName := c.joinArtists(raw["artists"])
+	trackArtistNames := artistNames(raw["artists"])
+	artistName := displayArtistNames(trackArtistNames)
 	artistID := firstArtistID(raw["artists"])
 	albumArtist := c.releaseArtistName(release["artists"])
 	if albumArtist == "" {
@@ -524,6 +525,7 @@ func (c *Client) normalizeTrack(raw map[string]any) map[string]any {
 		"version":               jsonutil.StringFromAny(raw["mix_name"]),
 		"artist":                map[string]any{"id": artistID, "name": artistName},
 		"performer":             map[string]any{"id": artistID, "name": artistName},
+		"artist_names":          trackArtistNames,
 		"album":                 map[string]any{"id": jsonutil.StringFromAny(release["id"]), "title": jsonutil.StringFromAny(release["name"]), "artist": map[string]any{"name": albumArtist}, "image": imageMap(release["image"]), "release_date_original": date},
 		"track_number":          jsonutil.IntFromAny(raw["number"]),
 		"tracks_count":          jsonutil.IntFromAny(release["track_count"]),
@@ -544,11 +546,12 @@ func (c *Client) normalizeTrack(raw map[string]any) map[string]any {
 }
 
 func (c *Client) normalizeTrackListItem(raw map[string]any) map[string]any {
+	names := artistNames(raw["artists"])
 	return map[string]any{
 		"id":           jsonutil.StringFromAny(raw["id"]),
 		"title":        jsonutil.StringFromAny(raw["name"]),
 		"version":      jsonutil.StringFromAny(raw["mix_name"]),
-		"artist":       map[string]any{"name": c.joinArtists(raw["artists"])},
+		"artist":       map[string]any{"name": displayArtistNames(names)},
 		"album":        map[string]any{"id": jsonutil.NestedString(raw, "release", "id"), "title": jsonutil.NestedString(raw, "release", "name")},
 		"track_number": jsonutil.IntFromAny(raw["number"]),
 	}
@@ -653,7 +656,7 @@ func audioProfile(quality, streamQuality string) (provider.AudioProfile, string)
 	}
 }
 
-func (c *Client) joinArtists(v any) string {
+func artistNames(v any) []string {
 	items := sliceAny(v)
 	names := make([]string, 0, len(items))
 	for _, raw := range items {
@@ -665,7 +668,20 @@ func (c *Client) joinArtists(v any) string {
 			names = append(names, name)
 		}
 	}
-	return strings.Join(names, artistSeparator(c.cfg.Session.Metadata.ArtistSeparator))
+	return names
+}
+
+func displayArtistNames(names []string) string {
+	switch len(names) {
+	case 0:
+		return ""
+	case 1:
+		return names[0]
+	case 2:
+		return names[0] + " & " + names[1]
+	default:
+		return strings.Join(names[:len(names)-1], ", ") + " & " + names[len(names)-1]
+	}
 }
 
 func (c *Client) releaseArtistName(v any) string {
@@ -674,14 +690,7 @@ func (c *Client) releaseArtistName(v any) string {
 	if threshold >= 0 && len(items) > threshold {
 		return "Various Artists"
 	}
-	return c.joinArtists(v)
-}
-
-func artistSeparator(separator string) string {
-	if separator == "" {
-		return "; "
-	}
-	return separator
+	return displayArtistNames(artistNames(v))
 }
 
 func firstArtistID(v any) string {

internal/provider/beatport/client_test.go

@@ -164,21 +164,19 @@ func TestReleaseArtistCollapseCanBeDisabled(t *testing.T) {
 		map[string]any{"name": "C"},
 		map[string]any{"name": "D"},
 	})
-	if got != "A; B; C; D" {
+	if got != "A, B, C & D" {
 		t.Fatalf("releaseArtistName() = %q", got)
 	}
 }
 
-func TestArtistSeparatorCanBeConfigured(t *testing.T) {
-	cfg := &config.Config{Session: config.DefaultConfigData(), File: config.DefaultConfigData()}
-	cfg.Session.Metadata.ArtistSeparator = " / "
-	c := New(cfg)
-	got := c.joinArtists([]any{
+func TestDisplayArtistNamesUsesCreditPunctuation(t *testing.T) {
+	got := displayArtistNames(artistNames([]any{
 		map[string]any{"name": "A"},
 		map[string]any{"name": "B"},
-	})
-	if got != "A / B" {
-		t.Fatalf("joinArtists() = %q", got)
+		map[string]any{"name": "C"},
+	}))
+	if got != "A, B & C" {
+		t.Fatalf("displayArtistNames() = %q", got)
 	}
 }