import AVFoundation
import SwiftUI

/// Audio-Wiedergabe-Button für `audio-front`-Karten. Lädt das File einmal
/// per MediaCache, spielt mit AVAudioPlayer ab.
struct AudioPlayerButton: View {
    let mediaId: String

    @Environment(\.mediaCache) private var mediaCache
    @State private var player: AVAudioPlayer?
    @State private var isPlaying = false
    @State private var failed = false

    var body: some View {
        Button {
            togglePlayback()
        } label: {
            HStack(spacing: 12) {
                Image(systemName: failed
                    ? "speaker.slash.fill"
                    : (isPlaying ? "pause.circle.fill" : "play.circle.fill"))
                    .font(.system(size: 48))
                    .foregroundStyle(failed ? CardsTheme.error : CardsTheme.primary)
                Text(failed ? "Audio nicht verfügbar" : (isPlaying ? "Wiedergabe läuft" : "Anhören"))
                    .font(.headline)
                    .foregroundStyle(CardsTheme.foreground)
            }
            .frame(maxWidth: .infinity)
            .padding(20)
            .background(CardsTheme.surface, in: RoundedRectangle(cornerRadius: 12))
            .overlay(
                RoundedRectangle(cornerRadius: 12)
                    .stroke(CardsTheme.border, lineWidth: 1)
            )
        }
        .buttonStyle(.plain)
        .disabled(failed)
        .task(id: mediaId) {
            await load()
        }
        .onDisappear {
            player?.stop()
            isPlaying = false
        }
    }

    private func load() async {
        guard let cache = mediaCache else { failed = true; return }
        do {
            let data = try await cache.data(for: mediaId)
            #if canImport(UIKit)
            try AVAudioSession.sharedInstance().setCategory(.playback, mode: .default)
            try AVAudioSession.sharedInstance().setActive(true)
            #endif
            player = try AVAudioPlayer(data: data)
            player?.prepareToPlay()
        } catch {
            failed = true
        }
    }

    private func togglePlayback() {
        guard let player else { return }
        if player.isPlaying {
            player.pause()
            isPlaying = false
        } else {
            player.currentTime = 0
            player.play()
            isPlaying = true
        }
    }
}