add AlbumFilter to backend album iterators

backend/albumiterator.go

@@ -3,8 +3,10 @@ package backend
 import (
 	"log"
 	"strconv"
+	"strings"
 
 	"github.com/dweymouth/go-subsonic/subsonic"
+	"github.com/dweymouth/supersonic/sharedutil"
 )
 
 type AlbumSortOrder string
@@ -33,36 +35,69 @@ var (
 	}
 )
 
-func (l *LibraryManager) AlbumsIter(sort AlbumSortOrder) AlbumIterator {
+type AlbumFilter struct {
+	MinYear int
+	MaxYear int      // 0 == unset/match any
+	Genres  []string // len(0) == unset/match any
+
+	ExcludeFavorited   bool // mut. exc. with ExcludeUnfavorited
+	ExcludeUnfavorited bool // mut. exc. with ExcludeFavorited
+}
+
+func (f *AlbumFilter) Matches(album *subsonic.AlbumID3) bool {
+	if album == nil {
+		return false
+	}
+	if f.ExcludeFavorited && !album.Starred.IsZero() {
+		return false
+	}
+	if f.ExcludeUnfavorited && album.Starred.IsZero() {
+		return false
+	}
+	if y := album.Year; y < f.MinYear || (f.MaxYear > 0 && y > f.MaxYear) {
+		return false
+	}
+	if len(f.Genres) == 0 {
+		return true
+	}
+	for _, g := range f.Genres {
+		if strings.EqualFold(g, album.Genre) {
+			return true
+		}
+	}
+	return false
+}
+
+func (l *LibraryManager) AlbumsIter(sort AlbumSortOrder, filter AlbumFilter) AlbumIterator {
 	switch sort {
 	case AlbumSortRecentlyAdded:
-		return l.newBaseIter("newest", make(map[string]string))
+		return l.newBaseIter("newest", filter, make(map[string]string))
 	case AlbumSortRecentlyPlayed:
-		return l.newBaseIter("recent", make(map[string]string))
+		return l.newBaseIter("recent", filter, make(map[string]string))
 	case AlbumSortFrequentlyPlayed:
-		return l.newBaseIter("frequent", make(map[string]string))
+		return l.newBaseIter("frequent", filter, make(map[string]string))
 	case AlbumSortRandom:
 		return l.newRandomIter()
 	case AlbumSortTitleAZ:
-		return l.newBaseIter("alphabeticalByName", make(map[string]string))
+		return l.newBaseIter("alphabeticalByName", filter, make(map[string]string))
 	case AlbumSortArtistAZ:
-		return l.newBaseIter("alphabeticalByArtist", make(map[string]string))
+		return l.newBaseIter("alphabeticalByArtist", filter, make(map[string]string))
 	case AlbumSortYearAscending:
-		return l.newBaseIter("byYear", map[string]string{"fromYear": "0", "toYear": "3000"})
+		return l.newBaseIter("byYear", filter, map[string]string{"fromYear": "0", "toYear": "3000"})
 	case AlbumSortYearDescending:
-		return l.newBaseIter("byYear", map[string]string{"fromYear": "3000", "toYear": "0"})
+		return l.newBaseIter("byYear", filter, map[string]string{"fromYear": "3000", "toYear": "0"})
 	default:
 		log.Printf("Undefined album sort order: %s", sort)
 		return nil
 	}
 }
 
-func (l *LibraryManager) StarredIter() AlbumIterator {
-	return l.newBaseIter("starred", make(map[string]string))
+func (l *LibraryManager) StarredIter(filter AlbumFilter) AlbumIterator {
+	return l.newBaseIter("starred", filter, make(map[string]string))
 }
 
-func (l *LibraryManager) GenreIter(genre string) AlbumIterator {
-	return l.newBaseIter("byGenre", map[string]string{"genre": genre})
+func (l *LibraryManager) GenreIter(genre string, filter AlbumFilter) AlbumIterator {
+	return l.newBaseIter("byGenre", filter, map[string]string{"genre": genre})
 }
 
 func (l *LibraryManager) SearchIter(query string) AlbumIterator {
@@ -83,6 +118,7 @@ func (l *LibraryManager) GetAlbum(id string) (*subsonic.AlbumID3, error) {
 
 type baseIter struct {
 	listType      string
+	filter        AlbumFilter
 	pos           int
 	l             *LibraryManager
 	s             *subsonic.Client
@@ -92,9 +128,10 @@ type baseIter struct {
 	done          bool
 }
 
-func (l *LibraryManager) newBaseIter(listType string, opts map[string]string) *baseIter {
+func (l *LibraryManager) newBaseIter(listType string, filter AlbumFilter, opts map[string]string) *baseIter {
 	return &baseIter{
 		listType: listType,
+		filter:   filter,
 		l:        l,
 		s:        l.s.Server,
 		opts:     opts,
@@ -123,6 +160,7 @@ func (r *baseIter) Next() *subsonic.AlbumID3 {
 		log.Println(err)
 		albums = nil
 	}
+	albums = sharedutil.FilterSlice(albums, r.filter.Matches)
 	if len(albums) == 0 {
 		r.done = true
 		return nil

backend/trackiterator.go

@@ -9,7 +9,7 @@ import (
 func (l *LibraryManager) AllTracksIterator() TrackIterator {
 	return &allTracksIterator{
 		l:         l,
-		albumIter: l.AlbumsIter(AlbumSortArtistAZ),
+		albumIter: l.AlbumsIter(AlbumSortArtistAZ, AlbumFilter{}),
 	}
 }