Now Playing Framework

import NowPlaying
import AVFoundation
import SwiftUI

// MARK: - Sound model
struct AmbientSound: Identifiable {
    let id: String
    let name: String
    let description: String
    let imageName: String
}

// MARK: - Player model conforming to MediaSessionRepresentable
@Observable
final class AmbientPlayerModel: MediaSessionRepresentable {

    // Required unique identifier for this session
    let id = "com.example.ambientplayer.session"

    private(set) var currentSound: AmbientSound = sounds[0]
    private(set) var isPlaying: Bool = false

    private let audioEngine = AVAudioEngine()

    // MARK: MediaSessionRepresentable – content
    var content: some MediaContentRepresentable {
        GenericContent(id: currentSound.id) {
            $0.title = currentSound.name
            $0.subtitle = currentSound.description
            $0.mediaType = .audio
            $0.duration = .continuous
            $0.artwork = Artwork { size in
                // Return UIImage scaled to requested size
                UIImage(named: self.currentSound.imageName)
            }
        }
    }

    // MARK: MediaSessionRepresentable – playback snapshot
    var playbackSnapshot: PlaybackSnapshot {
        PlaybackSnapshot(isPlaying: isPlaying)
    }

    // MARK: MediaSessionRepresentable – commands
    var commands: some MediaCommandRepresentable {
        PlayCommand {
            self.resume()
        }
        PauseCommand {
            self.pause()
        }
        NextTrackCommand {
            self.skipToNext()
        }
    }

    // MARK: Playback control
    func resume() { isPlaying = true  /* start audioEngine */ }
    func pause()  { isPlaying = false /* pause audioEngine  */ }
    func skipToNext() {
        let idx = (sounds.firstIndex(where: { $0.id == currentSound.id }) ?? 0)
        currentSound = sounds[(idx + 1) % sounds.count]
    }
}

// MARK: - Sample data
let sounds: [AmbientSound] = [
    AmbientSound(id: "rain",   name: "Rain",   description: "Gentle rainfall", imageName: "rain"),
    AmbientSound(id: "forest", name: "Forest", description: "Birds and wind",  imageName: "forest"),
    AmbientSound(id: "ocean",  name: "Ocean",  description: "Rolling waves",   imageName: "ocean"),
]

// MARK: - App entry point wiring MediaSession
@main
struct AmbientApp: App {
    @State private var player = AmbientPlayerModel()
    // MediaSession must be stored; it observes the model and drives system UI
    @State private var session: MediaSession<AmbientPlayerModel>?

    var body: some Scene {
        WindowGroup {
            ContentView(player: player)
                .onAppear {
                    session = MediaSession(representation: player)
                }
        }
    }
}

// MARK: - Simple UI
struct ContentView: View {
    let player: AmbientPlayerModel
    var body: some View {
        VStack(spacing: 20) {
            Text(player.currentSound.name).font(.title)
            Text(player.currentSound.description).foregroundStyle(.secondary)
            HStack(spacing: 30) {
                Button(player.isPlaying ? "Pause" : "Play") {
                    player.isPlaying ? player.pause() : player.resume()
                }
                Button("Next") { player.skipToNext() }
            }.buttonStyle(.bordered)
        }
        .padding()
    }
}