Scan nested artwork directories for covers

Author: akrylysov

media_detector.go

@@ -30,6 +30,13 @@ func IsAudioFile(f *StorageFile) bool {
 	return audioExtensions.Contains(ext)
 }
 
+var artworkDirNames = NewStringSet("scans", "covers", "artwork", "media")
+
+// IsArtworkDir returns whether the given directory may contain cover images.
+func IsArtworkDir(d *StorageDirectory) bool {
+	return artworkDirNames.Contains(strings.ToLower(d.Name()))
+}
+
 type ScoredFile struct {
 	*StorageFile
 	Score int

media_library.go

@@ -25,7 +25,6 @@ func NewMediaLibrary(store *S3Storage) *MediaLibrary {
 func (ml *MediaLibrary) findCover(files []*StorageFile) *StorageFile {
 	candidates := ScoreCovers(files)
 	if len(candidates) == 0 {
-		// TODO: look at subdirectories such as covers, scans and artwork.
 		return nil
 	}
 	sort.SliceStable(candidates, func(i, j int) bool {
@@ -34,16 +33,40 @@ func (ml *MediaLibrary) findCover(files []*StorageFile) *StorageFile {
 	return candidates[0].StorageFile
 }
 
+func (ml *MediaLibrary) listArtworkFiles(dirs []*StorageDirectory) ([]*StorageFile, error) {
+	var candidates []*StorageFile
+	for _, dir := range dirs {
+		if !IsArtworkDir(dir) {
+			continue
+		}
+		_, files, err := ml.store.List(dir.Path())
+		if err != nil {
+			return nil, err
+		}
+		candidates = append(candidates, files...)
+	}
+	return candidates, nil
+}
+
 // List returns directory listing under the provided path.
 func (ml *MediaLibrary) List(p string) (*MediaListing, error) {
 	dirs, files, err := ml.store.List(p)
 	if err != nil {
 		return nil, err
 	}
 
-	// Find album cover.
+	// Find album cover in the current directory.
 	cover := ml.findCover(files)
 
+	if cover == nil {
+		// Scan nested artwork directories for covers.
+		artworkFiles, err := ml.listArtworkFiles(dirs)
+		if err != nil {
+			return nil, err
+		}
+		cover = ml.findCover(artworkFiles)
+	}
+
 	// Find audio tracks and separate all other files.
 	var tracks []*StorageFile
 	var otherFiles []*StorageFile

media_library_test.go

@@ -32,7 +32,7 @@ func TestMediaLibrary(t *testing.T) {
 		"music/Aphex Twin/1999 - Windowlicker/Folder.jpg",
 		"music/Aphex Twin/1999 - Windowlicker/back.jpg",
 		"music/Aphex Twin/1999 - Windowlicker/covers/front_cover.jpg",
-		"music/The Prodigy/1992 - The Prodigy Experience/scans/Cover-Case.png",
+		"music/The Prodigy/1992 - The Prodigy Experience/Scans/Cover-Case.png",
 		"music/The Prodigy/1992 - The Prodigy Experience/CD1/01 - Jericho.mp3",
 		"music/The Prodigy/1992 - The Prodigy Experience/CD2/01 - Your Love.mp3",
 		"music/Venetian Snares/2016 - Traditional Synthesizer Music/01. Dreamt Person v3.mp3",
@@ -96,8 +96,9 @@ func TestMediaLibrary(t *testing.T) {
 			Directories: []*StorageDirectory{
 				NewStorageDirectory("The Prodigy/1992 - The Prodigy Experience/CD1"),
 				NewStorageDirectory("The Prodigy/1992 - The Prodigy Experience/CD2"),
-				NewStorageDirectory("The Prodigy/1992 - The Prodigy Experience/scans"),
+				NewStorageDirectory("The Prodigy/1992 - The Prodigy Experience/Scans"),
 			},
+			Cover: NewStorageFile("The Prodigy/1992 - The Prodigy Experience/Scans/Cover-Case.png", 1),
 		},
 		"The Prodigy/1992 - The Prodigy Experience/CD1": {
 			CurrentDirectory: NewStorageDirectory("The Prodigy/1992 - The Prodigy Experience/CD1"),
@@ -126,7 +127,7 @@ func TestMediaLibrary(t *testing.T) {
 	for path, expectedListing := range testCases {
 		l, err := ml.List(path)
 		asrt.NoError(err)
-		asrt.EqualValues(&expectedListing, l)
+		asrt.EqualValues(&expectedListing, l, path)
 	}
 
 	// Path doesn't exist.