From f631fdfa7cdd086d7ae18e4be1ea6de09614b8d9 Mon Sep 17 00:00:00 2001
From: "Alexander \"Arav\" Andreev" <me@arav.top>
Date: Mon, 19 Sep 2022 01:55:09 +0400
Subject: [PATCH] Playlist log watcher was made into a struct.

---
 cmd/dwelling-radio/main.go |  5 +++--
 internal/radio/icecast.go  | 34 ++++++++++++++++++++++------------
 2 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/cmd/dwelling-radio/main.go b/cmd/dwelling-radio/main.go
index fbcf055..e696a3d 100644
--- a/cmd/dwelling-radio/main.go
+++ b/cmd/dwelling-radio/main.go
@@ -51,10 +51,11 @@ func main() {
 	}
 	defer logErr.Close()
 
-	if err := radio.IcecastWatchPlaylist(config.Icecast.Playlist, config.ListLastNSongs); err != nil {
+	playlistWatcher := radio.NewPlaylistLogWatcher()
+	if err := playlistWatcher.Watch(config.Icecast.Playlist, config.ListLastNSongs); err != nil {
 		logErr.Fatalln(err)
 	}
-	defer radio.IcecastWatchClose()
+	defer playlistWatcher.Close()
 
 	hand := handlers.NewRadioHandlers(config, logErr)
 	srv := server.NewHttpServer()
diff --git a/internal/radio/icecast.go b/internal/radio/icecast.go
index 1511954..a2b28cb 100644
--- a/internal/radio/icecast.go
+++ b/internal/radio/icecast.go
@@ -166,35 +166,45 @@ func icecastLastPlayedSongs(playlistPath string, n int) ([]Song, error) {
 	return songs, nil
 }
 
-var playlistWatcher watcher.InotifyWatcher
-var playlistChanged chan uint32 = make(chan uint32)
+type PlaylistLogWatcher struct {
+	watcher *watcher.InotifyWatcher
+	changed chan uint32
+}
 
-func IcecastWatchPlaylist(playlistPath string, lastNSongs int) error {
-	playlistWatcher, err := watcher.NewInotifyWatcher()
+func NewPlaylistLogWatcher() *PlaylistLogWatcher {
+	return &PlaylistLogWatcher{changed: make(chan uint32)}
+}
+
+func (pw *PlaylistLogWatcher) Watch(playlistPath string, n int) (err error) {
+	if pw.watcher != nil {
+		pw.watcher.Close()
+	}
+
+	pw.watcher, err = watcher.NewInotifyWatcher()
 	if err != nil {
 		return errors.Wrap(err, "cannot instantiate inotify watcher")
 	}
 
-	err = playlistWatcher.AddWatch(playlistPath, watcher.ModIgnMask)
+	err = pw.watcher.AddWatch(playlistPath, watcher.ModIgnMask)
 	if err != nil {
 		return errors.Wrap(err, "cannot set a playlist to watch")
 	}
 
-	playlistWatcher.WatchForMask(playlistChanged, watcher.ModIgnMask)
+	pw.watcher.WatchForMask(pw.changed, watcher.ModIgnMask)
 
 	go func() {
 		for {
 			select {
-			case mask := <-playlistChanged:
+			case mask := <-pw.changed:
 				if mask&syscall.IN_MODIFY > 0 {
 					lastPlayedCacheMutex.Lock()
-					if songs, err := icecastLastPlayedSongs(playlistPath, lastNSongs); err == nil {
+					if songs, err := icecastLastPlayedSongs(playlistPath, n); err == nil {
 						lastPlayedCache = songs
 					}
 					lastPlayedCacheMutex.Unlock()
 				} else if mask&syscall.IN_IGNORED > 0 {
-					playlistWatcher.Close()
-					IcecastWatchPlaylist(playlistPath, lastNSongs)
+					pw.Close()
+					pw.Watch(playlistPath, n)
 					return
 				}
 			}
@@ -204,6 +214,6 @@ func IcecastWatchPlaylist(playlistPath string, lastNSongs int) error {
 	return nil
 }
 
-func IcecastWatchClose() {
-	playlistWatcher.Close()
+func (pw *PlaylistLogWatcher) Close() {
+	pw.watcher.Close()
 }