lastPlayedSong was made into lastPlayedSongs. Now it retrieves up to n songs from a log.

internal/radio/icecast.go

@@ -18,7 +18,7 @@ const (
 	IcecastPlaylistDateFormat = "02/Jan/2006:15:04:05 -0700"
 	SongTimeFormat            = "2006 15:04-0700"
 
-	bufferSize = 8192
+	bufferSize = 32768
 )
 
 var (
@@ -92,7 +92,12 @@ func IcecastLastPlayedSongs(lastNSongs int, playlistPath string) ([]Song, error)
 		}
 	}
 
-	return make([]Song, 0), nil
+	songs, err := lastPlayedSongs(playlistPath, lastNSongs)
+	if err != nil {
+		return make([]Song, 0), err
+	}
+
+	return songs, nil
 }
 
 func IcecastLastSong(playlistPath string) (Song, error) {
@@ -104,15 +109,16 @@ func IcecastLastSong(playlistPath string) (Song, error) {
 		}
 	}
 
-	song, err := lastPlayedSong(playlistPath)
+	song, err := lastPlayedSongs(playlistPath, 1)
 	if err != nil {
 		return Song{}, err
 	}
 
-	return *song, nil
+	return song[0], nil
 }
 
-func lastPlayedSong(playlistPath string) (*Song, error) {
+func lastPlayedSongs(playlistPath string, n int) ([]Song, error) {
+	songs := make([]Song, n)
 	buf := make([]byte, bufferSize)
 
 	playlist, err := os.Open(playlistPath)
@@ -140,14 +146,24 @@ func lastPlayedSong(playlistPath string) (*Song, error) {
 		return nil, nil
 	}
 
-	fields := bytes.Split(lines[len(lines)-3], []byte("|"))
+	if len(lines) < n {
+		n = len(lines)
+	}
+
+	lines = lines[len(lines)-n-3 : len(lines)-3]
+
+	for _, line := range lines {
+		fields := bytes.Split(line, []byte("|"))
 
 		tim, _ := time.Parse(IcecastPlaylistDateFormat, string(fields[0]))
 
-	return &Song{
+		songs = append(songs, Song{
 			Time:      tim.Format(SongTimeFormat),
 			Listeners: string(fields[2]),
-		Song:      string(fields[3])}, nil
+			Song:      string(fields[3])})
+	}
+
+	return songs, nil
 }
 
 var playlistWatcher watcher.InotifyWatcher
@@ -172,11 +188,8 @@ func IcecastWatchPlaylist(playlistPath string, lastNSongs int) error {
 			case mask := <-playlistFired:
 				if mask&syscall.IN_MODIFY > 0 {
 					lastPlayedCacheMutex.Lock()
-					if song, err := lastPlayedSong(playlistPath); err == nil {
-						lastPlayedCache = append(lastPlayedCache, *song)
-						if len(lastPlayedCache) > lastNSongs {
-							lastPlayedCache = lastPlayedCache[1:]
-						}
+					if songs, err := lastPlayedSongs(playlistPath, lastNSongs); err == nil {
+						lastPlayedCache = songs
 					}
 					lastPlayedCacheMutex.Unlock()
 				} else if mask&syscall.IN_IGNORED > 0 {