Return Control Center to the system when not needed anymore

Sources/Player/ControlCenter/NowPlaying.swift

@@ -4,20 +4,33 @@
 //  License information is available from the LICENSE file.
 //
 
-/// Metadata describing what is currently being played.
-struct NowPlaying {
-    typealias Info = [String: Any]
+import MediaPlayer
 
-    static let empty = Self(metadata: .empty, playbackInfo: [:])
+/// Metadata describing what is currently being played.
+enum NowPlaying {
+    case empty
+    case filled(metadata: PlayerMetadata, playbackInfo: Info)
 
-    let metadata: PlayerMetadata
-    let playbackInfo: Info
+    typealias Info = [String: Any]
 
-    var isEmpty: Bool {
-        metadata == .empty && playbackInfo.isEmpty
+    var info: Info {
+        switch self {
+        case .empty:
+            [:]
+        case let .filled(metadata, playbackInfo):
+            metadata.nowPlayingInfo
+                .merging(playbackInfo) { _, new in new }
+                // For proper Control Center integration at least one metadata key must be filled.
+                .merging([MPMediaItemPropertyTitle: ""]) { old, _ in old }
+        }
     }
 
-    var info: Info {
-        metadata.nowPlayingInfo.merging(playbackInfo) { _, new in new }
+    var isEmpty: Bool {
+        switch self {
+        case .empty:
+            true
+        default:
+            false
+        }
     }
 }

Sources/Player/Player+ControlCenter.swift

@@ -46,15 +46,8 @@ private extension Player {
 
     func playRegistration() -> some RemoteCommandRegistrable {
         nowPlayingSession.remoteCommandCenter.register(command: \.playCommand) { [weak self] _ in
-            guard let self else { return .commandFailed }
-            if canReplay() {
-                replay()
-                return .commandFailed
-            }
-            else {
-                play()
-                return .success
-            }
+            self?.play()
+            return .success
         }
     }
 
@@ -120,29 +113,28 @@ extension Player {
         propertiesPublisher
             .map { [weak queuePlayer] properties in
                 var nowPlayingInfo = NowPlaying.Info()
-                // Always fill a key so that the Control Center can be enabled for the item, even if it has no associated metadata.
-                nowPlayingInfo[MPNowPlayingInfoPropertyIsLiveStream] = (properties.streamType == .live)
                 if properties.streamType != .unknown {
                     nowPlayingInfo[MPNowPlayingInfoPropertyPlaybackRate] = properties.isBuffering ? 0 : properties.rate
                     if let time = properties.seekTime ?? queuePlayer?.currentTime(), time.isValid {
                         nowPlayingInfo[MPNowPlayingInfoPropertyElapsedPlaybackTime] = (time - properties.seekableTimeRange.start).seconds
                     }
                     nowPlayingInfo[MPMediaItemPropertyPlaybackDuration] = properties.seekableTimeRange.duration.seconds
+                    nowPlayingInfo[MPNowPlayingInfoPropertyIsLiveStream] = (properties.streamType == .live)
                 }
                 return nowPlayingInfo
             }
             .eraseToAnyPublisher()
     }
 
     func nowPlayingPublisher() -> AnyPublisher<NowPlaying, Never> {
-        $isActive
-            .map { [weak self] isActive in
-                guard let self, isActive else { return Just(NowPlaying.empty).eraseToAnyPublisher() }
+        Publishers.CombineLatest($isActive, queuePublisher)
+            .map { [weak self] isActive, queue in
+                guard let self, isActive, !queue.isActive else { return Just(NowPlaying.empty).eraseToAnyPublisher() }
                 return Publishers.CombineLatest(
                     metadataPublisher,
                     nowPlayingInfoPlaybackPublisher()
                 )
-                .map { NowPlaying(metadata: $0, playbackInfo: $1) }
+                .map { NowPlaying.filled(metadata: $0, playbackInfo: $1) }
                 .eraseToAnyPublisher()
             }
             .switchToLatest()

Sources/Player/Types/Queue.swift

@@ -30,6 +30,10 @@ struct Queue {
         itemState.error
     }
 
+    var isActive: Bool {
+        playerItem == nil
+    }
+
     private var playerItem: AVPlayerItem? {
         itemState.item
     }

Tests/PlayerTests/Publishers/NowPlayingInfoPublisherTests.swift

@@ -15,6 +15,7 @@ final class NowPlayingInfoPublisherTests: TestCase {
     private static func nowPlayingInfoPublisher(for player: Player) -> AnyPublisher<NowPlaying.Info, Never> {
         player.nowPlayingPublisher()
             .map(\.info)
+            .removeDuplicates(by: ~~)
             .eraseToAnyPublisher()
     }
 
@@ -29,7 +30,7 @@ final class NowPlayingInfoPublisherTests: TestCase {
     func testToggleActive() {
         let player = Player(item: .mock(url: Stream.onDemand.url, loadedAfter: 0, withMetadata: AssetMetadataMock(title: "title")))
         expectAtLeastSimilarPublished(
-            values: [[:], [MPNowPlayingInfoPropertyIsLiveStream: false]],
+            values: [[:], ["title": ""], ["title": "title"]],
             from: Self.nowPlayingInfoPublisher(for: player)
         ) {
             player.isActive = true