refactor(player): update playlist handling and library refresh notifications

Signed-off-by: samzong <samzong.lu@gmail.com>

Author: samzong

MacMusicPlayer/AppDelegate.swift

@@ -155,7 +155,7 @@ class AppDelegate: NSObject, NSApplicationDelegate {
         if oldMenu == nil {
             NotificationCenter.default.addObserver(self, selector: #selector(updateMenuItems), name: NSNotification.Name("TrackChanged"), object: nil)
             NotificationCenter.default.addObserver(self, selector: #selector(updateMenuItems), name: NSNotification.Name("PlaybackStateChanged"), object: nil)
-            NotificationCenter.default.addObserver(self, selector: #selector(updateMenuItems), name: NSNotification.Name("RefreshMusicLibrary"), object: nil)
+            NotificationCenter.default.addObserver(self, selector: #selector(updateMenuItems), name: NSNotification.Name("PlaylistUpdated"), object: nil)
         }
 
         statusItem?.menu = menu
@@ -441,9 +441,10 @@ class AppDelegate: NSObject, NSApplicationDelegate {
     }
 
     @objc func refreshCurrentLibrary() {
-        guard libraryManager.currentLibrary != nil else { return }
+        guard let currentLibrary = libraryManager.currentLibrary else { return }
 
-        NotificationCenter.default.post(name: NSNotification.Name("RefreshMusicLibrary"), object: nil)
+        // Simply reload the library, same as startup
+        playerManager.loadLibrary(currentLibrary)
 
         if let button = statusItem?.button,
            let refreshingIcon = makeStatusBarImage(symbolName: "arrow.clockwise", accessibilityDescription: "Refreshing") {

MacMusicPlayer/Managers/PlayerManager.swift

@@ -209,13 +209,19 @@ class PlayerManager: NSObject, ObservableObject {
             // Legacy playlist for backward compatibility
             self.playlist = sortedTracks
 
-            // If there are songs, set the first one as current track
+            // Set first track as current if available
             if !sortedTracks.isEmpty {
                 self.currentIndex = 0
                 self.currentTrack = sortedTracks[0]
-                // Set up queue with all tracks starting at index 0
+                self.playlistStore.setCurrentIndex(0)
                 self.queueController.setQueue(sortedTracks, startingAt: 0)
+            } else {
+                self.currentTrack = nil
+                self.currentIndex = 0
             }
+            
+            // Notify that playlist has been updated
+            NotificationCenter.default.post(name: NSNotification.Name("PlaylistUpdated"), object: nil)
         }
     }
 
@@ -340,7 +346,7 @@ class PlayerManager: NSObject, ObservableObject {
 
 
     @objc func refreshMusicLibrary() {
-        // Check if there is a current library
+        // Simply reload the current library, same as startup
         if let library = (NSApplication.shared.delegate as? AppDelegate)?.libraryManager.currentLibrary {
             loadLibrary(library)
         } else {

MacMusicPlayer/Views/SimpleSongPickerWindow.swift

@@ -6,6 +6,7 @@
 //
 
 import Cocoa
+import Combine
 
 class SimpleSongPickerWindow: NSPanel {
     private weak var playerManager: PlayerManager?
@@ -17,6 +18,7 @@ class SimpleSongPickerWindow: NSPanel {
     private var allTracks: [Track] = []
     private var filteredTracks: [Track] = []
     private var filterWorkItem: DispatchWorkItem?
+    private var playlistCancellable: AnyCancellable?
 
     private let windowWidth: CGFloat = 600
     private let windowHeight: CGFloat = 400
@@ -36,24 +38,33 @@ class SimpleSongPickerWindow: NSPanel {
         setupViews()
         loadTracks()
 
-        // Listen for music library refresh notification
+        // Listen for playlist updates
         NotificationCenter.default.addObserver(
             self,
-            selector: #selector(handleRefreshMusicLibrary),
-            name: NSNotification.Name("RefreshMusicLibrary"),
+            selector: #selector(handlePlaylistUpdated),
+            name: NSNotification.Name("PlaylistUpdated"),
             object: nil
         )
+
+        if let playerManager = self.playerManager {
+            playlistCancellable = playerManager.$playlist
+                .receive(on: DispatchQueue.main)
+                .sink { [weak self] _ in
+                    self?.loadTracks()
+                }
+        }
     }
 
     override var canBecomeKey: Bool { true }
 
     deinit {
         filterWorkItem?.cancel()
+        playlistCancellable?.cancel()
         NotificationCenter.default.removeObserver(self)
     }
 
-    @objc private func handleRefreshMusicLibrary() {
-        // Reload tracks when music library is refreshed
+    @objc private func handlePlaylistUpdated() {
+        // Reload tracks when playlist is updated
         loadTracks()
     }