feat(player): add mobile edge adjustments

ios/Runner/AppDelegate.swift

@@ -1,9 +1,15 @@
 import Flutter
 import UIKit
 import AVFoundation
+import MediaPlayer
 
 @main
 @objc class AppDelegate: FlutterAppDelegate, FlutterImplicitEngineDelegate {
+  private var deviceAdjustmentChannel: FlutterMethodChannel?
+  private var originalBrightness: CGFloat?
+  private var volumeView: MPVolumeView?
+  private weak var volumeSlider: UISlider?
+
   override func application(
     _ application: UIApplication,
     didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?
@@ -29,5 +35,117 @@ import AVFoundation
     if let registrar = engineBridge.pluginRegistry.registrar(forPlugin: "MpvPlayerPlugin") {
       MpvPlayerPlugin.register(with: registrar)
     }
+
+    if let registrar = engineBridge.pluginRegistry.registrar(forPlugin: "DeviceAdjustmentChannel") {
+      registerDeviceAdjustmentChannel(messenger: registrar.messenger())
+    }
+  }
+
+  private func registerDeviceAdjustmentChannel(messenger: FlutterBinaryMessenger) {
+    let channel = FlutterMethodChannel(name: "com.plezy/device_adjustment", binaryMessenger: messenger)
+    channel.setMethodCallHandler { [weak self] call, result in
+      DispatchQueue.main.async {
+        self?.handleDeviceAdjustmentCall(call, result: result)
+      }
+    }
+    deviceAdjustmentChannel = channel
+  }
+
+  private func handleDeviceAdjustmentCall(_ call: FlutterMethodCall, result: @escaping FlutterResult) {
+    switch call.method {
+    case "getBrightness":
+      result(Double(UIScreen.main.brightness))
+    case "setBrightness":
+      guard let value = normalizedArgument(call.arguments, result: result) else { return }
+      if originalBrightness == nil {
+        originalBrightness = UIScreen.main.brightness
+      }
+      UIScreen.main.brightness = CGFloat(value)
+      result(nil)
+    case "restoreBrightness":
+      if let originalBrightness = originalBrightness {
+        UIScreen.main.brightness = originalBrightness
+        self.originalBrightness = nil
+      }
+      result(nil)
+    case "getMediaVolume":
+      result(Double(AVAudioSession.sharedInstance().outputVolume))
+    case "setMediaVolume":
+      guard let value = normalizedArgument(call.arguments, result: result) else { return }
+      if setMediaVolume(value) {
+        result(nil)
+      } else {
+        result(FlutterError(code: "DEVICE_ADJUSTMENT_UNAVAILABLE", message: "System volume slider unavailable", details: nil))
+      }
+    default:
+      result(FlutterMethodNotImplemented)
+    }
+  }
+
+  private func normalizedArgument(_ arguments: Any?, result: @escaping FlutterResult) -> Double? {
+    guard let value = arguments as? NSNumber else {
+      result(FlutterError(code: "INVALID_ARGUMENT", message: "Expected a numeric value", details: nil))
+      return nil
+    }
+    let doubleValue = value.doubleValue
+    guard doubleValue.isFinite else {
+      result(FlutterError(code: "INVALID_ARGUMENT", message: "Expected a finite numeric value", details: nil))
+      return nil
+    }
+    return min(1.0, max(0.0, doubleValue))
+  }
+
+  private func setMediaVolume(_ value: Double) -> Bool {
+    guard let slider = ensureVolumeSlider() else { return false }
+    slider.setValue(Float(value), animated: false)
+    slider.sendActions(for: .valueChanged)
+    slider.sendActions(for: .touchUpInside)
+    return true
+  }
+
+  private func ensureVolumeSlider() -> UISlider? {
+    if let volumeSlider = volumeSlider { return volumeSlider }
+
+    let volumeView = self.volumeView ?? MPVolumeView(frame: CGRect(x: -1000, y: -1000, width: 1, height: 1))
+    volumeView.showsRouteButton = false
+    volumeView.showsVolumeSlider = true
+    volumeView.alpha = 0.01
+    volumeView.isUserInteractionEnabled = false
+
+    if volumeView.superview == nil {
+      activeWindow?.addSubview(volumeView)
+    }
+    volumeView.layoutIfNeeded()
+
+    self.volumeView = volumeView
+    let slider = findVolumeSlider(in: volumeView)
+    volumeSlider = slider
+    return slider
+  }
+
+  private func findVolumeSlider(in view: UIView) -> UISlider? {
+    if let slider = view as? UISlider { return slider }
+    for subview in view.subviews {
+      if let slider = findVolumeSlider(in: subview) { return slider }
+    }
+    return nil
+  }
+
+  private var activeWindow: UIWindow? {
+    if #available(iOS 13.0, *) {
+      for scene in UIApplication.shared.connectedScenes {
+        guard let windowScene = scene as? UIWindowScene else { continue }
+        if let keyWindow = windowScene.windows.first(where: { $0.isKeyWindow }) {
+          return keyWindow
+        }
+      }
+      for scene in UIApplication.shared.connectedScenes {
+        guard let windowScene = scene as? UIWindowScene, let window = windowScene.windows.first else { continue }
+        return window
+      }
+      return nil
+    }
+
+    return UIApplication.shared.windows.first(where: { $0.isKeyWindow }) ?? UIApplication.shared.windows.first
   }
 }