Library indexing and filesystem scanner with incremental rescans

internal/library/browse.go

@@ -0,0 +1,58 @@
+package library
+
+import (
+	"database/sql"
+	"strings"
+
+	"git.noroutes.net/NoRoutes/vibetunes/internal/database"
+)
+
+// DirEntry is one immediate child of a directory in filesystem-style
+// browsing (Subsonic's getIndexes/getMusicDirectory): either a
+// subdirectory (Dir=true) or a media file.
+type DirEntry struct {
+	Name string
+	Dir  bool
+	File *database.MediaFile // set when Dir is false
+}
+
+// ListDirectory returns the immediate children of subPath within a music
+// folder ("" for the folder root), built from media_files.relative_path.
+// This is the foundation for filesystem-style browsing, kept separate
+// from the ID3/tag model in library/index.go so neither is faked in
+// terms of the other.
+func ListDirectory(db *sql.DB, folderID, subPath string) ([]DirEntry, error) {
+	files, err := database.ListMediaFilesForFolder(db, folderID)
+	if err != nil {
+		return nil, err
+	}
+
+	prefix := strings.Trim(subPath, "/")
+	seen := make(map[string]bool)
+	var out []DirEntry
+	for _, f := range files {
+		if f.Missing {
+			continue
+		}
+		rel := f.RelativePath
+		if prefix != "" {
+			if !strings.HasPrefix(rel, prefix+"/") {
+				continue
+			}
+			rel = rel[len(prefix)+1:]
+		}
+		parts := strings.SplitN(rel, "/", 2)
+		name := parts[0]
+		if name == "" || seen[name] {
+			continue
+		}
+		if len(parts) == 2 {
+			seen[name] = true
+			out = append(out, DirEntry{Name: name, Dir: true})
+			continue
+		}
+		seen[name] = true
+		out = append(out, DirEntry{Name: name, Dir: false, File: f})
+	}
+	return out, nil
+}