feat: allow for custom music folder path alias

closes #259

paths/paths.go

@@ -0,0 +1,61 @@
+package paths
+
+import (
+	"fmt"
+	"path/filepath"
+	"strings"
+)
+
+const sep = "->"
+
+type MusicPaths []MusicPath
+
+func (mps MusicPaths) String() string {
+	var strs []string
+	for _, path := range mps {
+		strs = append(strs, path.String())
+	}
+	return strings.Join(strs, ", ")
+}
+
+func (mps *MusicPaths) Set(value string) error {
+	alias, path, ok := strings.Cut(value, sep)
+	if !ok {
+		*mps = append(*mps, MusicPath{
+			Path: filepath.Clean(strings.TrimSpace(value)),
+		})
+		return nil
+	}
+	*mps = append(*mps, MusicPath{
+		Alias: strings.TrimSpace(alias),
+		Path:  filepath.Clean(strings.TrimSpace(path)),
+	})
+	return nil
+}
+
+func (mps MusicPaths) Paths() []string {
+	var paths []string
+	for _, mp := range mps {
+		paths = append(paths, mp.Path)
+	}
+	return paths
+}
+
+type MusicPath struct {
+	Alias string
+	Path  string
+}
+
+func (mp MusicPath) String() string {
+	if mp.Alias == "" {
+		return mp.Path
+	}
+	return fmt.Sprintf("%s %s %s", mp.Alias, sep, mp.Path)
+}
+
+func (mp MusicPath) DisplayAlias() string {
+	if mp.Alias == "" {
+		return filepath.Base(mp.Path)
+	}
+	return mp.Alias
+}