functional carplay experience in simulators

2026-05-17 18:35:01 -07:00
parent e3288e044a
commit b8e86263d9
5 changed files with 450 additions and 11 deletions
@@ -2,12 +2,76 @@ import Flutter
 import UIKit
 import AVFoundation
 import AVKit
+import MediaPlayer
+
+private struct CarPlayPlaybackSnapshot {
+  var playbackStatus: String
+  var title: String
+  var subtitle: String
+  var album: String
+  var isLive: Bool
+  var seekable: Bool
+
+  static let `default` = CarPlayPlaybackSnapshot(
+    playbackStatus: "stopped",
+    title: "KRYZ Live Stream",
+    subtitle: "KRYZ Radio",
+    album: "Live",
+    isLive: true,
+    seekable: false
+  )
+
+  init(
+    playbackStatus: String,
+    title: String,
+    subtitle: String,
+    album: String,
+    isLive: Bool,
+    seekable: Bool
+  ) {
+    self.playbackStatus = playbackStatus
+    self.title = title
+    self.subtitle = subtitle
+    self.album = album
+    self.isLive = isLive
+    self.seekable = seekable
+  }
+
+  init(payload: [String: Any], fallback: CarPlayPlaybackSnapshot) {
+    let status = (payload["playbackStatus"] as? String)?.trimmingCharacters(in: .whitespacesAndNewlines)
+    let title = (payload["title"] as? String)?.trimmingCharacters(in: .whitespacesAndNewlines)
+    let subtitle = (payload["subtitle"] as? String)?.trimmingCharacters(in: .whitespacesAndNewlines)
+    let album = (payload["album"] as? String)?.trimmingCharacters(in: .whitespacesAndNewlines)
+
+    playbackStatus = (status?.isEmpty == false) ? status! : fallback.playbackStatus
+    self.title = (title?.isEmpty == false) ? title! : fallback.title
+    self.subtitle = (subtitle?.isEmpty == false) ? subtitle! : fallback.subtitle
+    self.album = (album?.isEmpty == false) ? album! : fallback.album
+    isLive = payload["isLive"] as? Bool ?? fallback.isLive
+    seekable = payload["seekable"] as? Bool ?? fallback.seekable
+  }
+
+  func asDictionary() -> [String: Any] {
+    [
+      "playbackStatus": playbackStatus,
+      "title": title,
+      "subtitle": subtitle,
+      "album": album,
+      "isLive": isLive,
+      "seekable": seekable
+    ]
+  }
+}

@main
@objc class AppDelegate: FlutterAppDelegate, FlutterImplicitEngineDelegate, FlutterStreamHandler {
  private let castingMethodChannelName = "kryz_go_flutter/casting/methods"
  private let castingEventChannelName = "kryz_go_flutter/casting/events"
  private let playbackMethodChannelName = "kryz_go_flutter/playback/methods"
+  private let carPlayMethodChannelName = "kryz_go_flutter/carplay/methods"
+
+  static let carPlaySnapshotDidChangeNotification = Notification.Name("KRYZCarPlaySnapshotDidChange")
+  static let carPlaySnapshotUserInfoKey = "snapshot"

  private var castingEventSink: FlutterEventSink?
  private var castingStatus: [String: Any] = [
@@ -15,6 +79,13 @@ import AVKit
    "platform": "ios"
  ]
  private var playbackMethodChannel: FlutterMethodChannel?
+  private var carPlayMethodChannel: FlutterMethodChannel?
+  private var carPlaySnapshot = CarPlayPlaybackSnapshot.default
+  private var headlessFlutterEngine: FlutterEngine?
+  private var playCommandTarget: Any?
+  private var togglePlayPauseCommandTarget: Any?
+  private var pauseCommandTarget: Any?
+  private var stopCommandTarget: Any?

  override func application(
    _ application: UIApplication,
@@ -37,14 +108,67 @@ import AVKit
    )

    updateCastingStatusForCurrentRoute()
+    ensureFlutterBridgeReadyForCarPlay()

    return super.application(application, didFinishLaunchingWithOptions: launchOptions)
  }

  func didInitializeImplicitFlutterEngine(_ engineBridge: FlutterImplicitEngineBridge) {
    GeneratedPluginRegistrant.register(with: engineBridge.pluginRegistry)
+    configureChannels(with: engineBridge.pluginRegistry)

-    guard let registrar = engineBridge.pluginRegistry.registrar(forPlugin: "CastingBridge") else {
+    if let engine = headlessFlutterEngine {
+      engine.destroyContext()
+      headlessFlutterEngine = nil
+    }
+  }
+
+  /// Invoke play on the Flutter audio engine. Called by CarPlaySceneDelegate.
+  func invokePlay() {
+    ensureFlutterBridgeReadyForCarPlay()
+    playbackMethodChannel?.invokeMethod("play", arguments: nil)
+  }
+
+  /// Invoke stop on the Flutter audio engine. Called by CarPlaySceneDelegate.
+  func invokeStop() {
+    ensureFlutterBridgeReadyForCarPlay()
+    playbackMethodChannel?.invokeMethod("stop", arguments: nil)
+  }
+
+  func currentCarPlaySnapshot() -> [String: Any] {
+    carPlaySnapshot.asDictionary()
+  }
+
+  func requestCarPlaySnapshot() {
+    ensureFlutterBridgeReadyForCarPlay()
+    carPlayMethodChannel?.invokeMethod("getStateSnapshot", arguments: nil) { [weak self] response in
+      guard let payload = response as? [String: Any] else {
+        return
+      }
+
+      self?.applyCarPlaySnapshot(payload)
+    }
+  }
+
+  func ensureFlutterBridgeReadyForCarPlay() {
+    if playbackMethodChannel != nil, carPlayMethodChannel != nil {
+      return
+    }
+
+    if let engine = headlessFlutterEngine {
+      configureChannels(with: engine)
+      return
+    }
+
+    let engine = FlutterEngine(name: "kryz_carplay_headless_engine", project: nil, allowHeadlessExecution: true)
+    headlessFlutterEngine = engine
+    engine.run()
+    GeneratedPluginRegistrant.register(with: engine)
+    configureChannels(with: engine)
+  }
+
+  private func configureChannels(with registry: FlutterPluginRegistry) {
+    guard let registrar = registry.registrar(forPlugin: "CastingBridge") else {
      return
    }

@@ -67,16 +191,17 @@ import AVKit
      name: playbackMethodChannelName,
      binaryMessenger: registrar.messenger()
    )
-  }

-  /// Invoke play on the Flutter audio engine. Called by CarPlaySceneDelegate.
-  func invokePlay() {
-    playbackMethodChannel?.invokeMethod("play", arguments: nil)
-  }
+    carPlayMethodChannel = FlutterMethodChannel(
+      name: carPlayMethodChannelName,
+      binaryMessenger: registrar.messenger()
+    )
+    carPlayMethodChannel?.setMethodCallHandler { [weak self] call, result in
+      self?.handleCarPlayMethod(call: call, result: result)
+    }

-  /// Invoke stop on the Flutter audio engine. Called by CarPlaySceneDelegate.
-  func invokeStop() {
-    playbackMethodChannel?.invokeMethod("stop", arguments: nil)
+    configureRemoteCommandCenterIfNeeded()
+    requestCarPlaySnapshot()
  }

  @objc private func handleAudioRouteChange() {
@@ -103,6 +228,132 @@ import AVKit
    }
  }

+  private func handleCarPlayMethod(call: FlutterMethodCall, result: @escaping FlutterResult) {
+    switch call.method {
+    case "syncState":
+      guard let payload = call.arguments as? [String: Any] else {
+        result(
+          FlutterError(
+            code: "invalid_payload",
+            message: "Expected map payload for syncState",
+            details: nil
+          )
+        )
+        return
+      }
+
+      applyCarPlaySnapshot(payload)
+      result(nil)
+    case "getCachedState":
+      result(carPlaySnapshot.asDictionary())
+    default:
+      result(FlutterMethodNotImplemented)
+    }
+  }
+
+  private func applyCarPlaySnapshot(_ payload: [String: Any]) {
+    carPlaySnapshot = CarPlayPlaybackSnapshot(payload: payload, fallback: carPlaySnapshot)
+    updateNowPlayingInfoCenter(using: carPlaySnapshot)
+    NotificationCenter.default.post(
+      name: Self.carPlaySnapshotDidChangeNotification,
+      object: self,
+      userInfo: [Self.carPlaySnapshotUserInfoKey: carPlaySnapshot.asDictionary()]
+    )
+  }
+
+  private func updateNowPlayingInfoCenter(using snapshot: CarPlayPlaybackSnapshot) {
+    var nowPlayingInfo = MPNowPlayingInfoCenter.default().nowPlayingInfo ?? [:]
+    nowPlayingInfo[MPMediaItemPropertyTitle] = snapshot.title
+    nowPlayingInfo[MPMediaItemPropertyArtist] = snapshot.subtitle
+    nowPlayingInfo[MPMediaItemPropertyAlbumTitle] = snapshot.album
+    nowPlayingInfo[MPNowPlayingInfoPropertyIsLiveStream] = snapshot.isLive
+    nowPlayingInfo[MPNowPlayingInfoPropertyPlaybackRate] = snapshot.playbackStatus == "playing" ? 1.0 : 0.0
+    nowPlayingInfo[MPNowPlayingInfoPropertyElapsedPlaybackTime] = 0.0
+    MPNowPlayingInfoCenter.default().nowPlayingInfo = nowPlayingInfo
+
+    if #available(iOS 13.0, *) {
+      let playbackState: MPNowPlayingPlaybackState = switch snapshot.playbackStatus {
+      case "playing":
+        .playing
+      case "buffering":
+        .playing
+      default:
+        .stopped
+      }
+      MPNowPlayingInfoCenter.default().playbackState = playbackState
+    }
+  }
+
+  private func configureRemoteCommandCenterIfNeeded() {
+    if playCommandTarget != nil ||
+      togglePlayPauseCommandTarget != nil ||
+      pauseCommandTarget != nil ||
+      stopCommandTarget != nil {
+      return
+    }
+
+    let commandCenter = MPRemoteCommandCenter.shared()
+    commandCenter.changePlaybackPositionCommand.isEnabled = false
+    commandCenter.seekForwardCommand.isEnabled = false
+    commandCenter.seekBackwardCommand.isEnabled = false
+    commandCenter.nextTrackCommand.isEnabled = false
+    commandCenter.previousTrackCommand.isEnabled = false
+
+    commandCenter.playCommand.isEnabled = true
+    playCommandTarget = commandCenter.playCommand.addTarget { [weak self] _ in
+      self?.invokePlay()
+      return .success
+    }
+
+    commandCenter.togglePlayPauseCommand.isEnabled = true
+    togglePlayPauseCommandTarget = commandCenter.togglePlayPauseCommand.addTarget { [weak self] _ in
+      guard let self else {
+        return .commandFailed
+      }
+
+      switch self.carPlaySnapshot.playbackStatus {
+      case "playing", "buffering":
+        self.invokeStop()
+      default:
+        self.invokePlay()
+      }
+
+      return .success
+    }
+
+    commandCenter.pauseCommand.isEnabled = true
+    pauseCommandTarget = commandCenter.pauseCommand.addTarget { [weak self] _ in
+      self?.invokeStop()
+      return .success
+    }
+
+    commandCenter.stopCommand.isEnabled = true
+    stopCommandTarget = commandCenter.stopCommand.addTarget { [weak self] _ in
+      self?.invokeStop()
+      return .success
+    }
+  }
+
+  private func teardownRemoteCommandCenter() {
+    let commandCenter = MPRemoteCommandCenter.shared()
+    if let target = playCommandTarget {
+      commandCenter.playCommand.removeTarget(target)
+    }
+    if let target = togglePlayPauseCommandTarget {
+      commandCenter.togglePlayPauseCommand.removeTarget(target)
+    }
+    if let target = pauseCommandTarget {
+      commandCenter.pauseCommand.removeTarget(target)
+    }
+    if let target = stopCommandTarget {
+      commandCenter.stopCommand.removeTarget(target)
+    }
+    playCommandTarget = nil
+    togglePlayPauseCommandTarget = nil
+    pauseCommandTarget = nil
+    stopCommandTarget = nil
+  }
+
  private func showAirPlayPicker() {
    DispatchQueue.main.async {
      guard let rootViewController = self.activeRootViewController() else {
@@ -176,5 +427,6 @@ import AVKit

  deinit {
    NotificationCenter.default.removeObserver(self)
+    teardownRemoteCommandCenter()
  }
 }