import Flutter

public class OtaPlugin: NSObject, FlutterPlugin, FlutterStreamHandler {
  var userManager: JLBleManager?
  var eventSink: FlutterEventSink?

  public static func register(with registrar: FlutterPluginRegistrar) {
    let channel = FlutterMethodChannel(name: "ota", binaryMessenger: registrar.messenger())
    let eventChannel = FlutterEventChannel(name: "com.example.ota/events", binaryMessenger: registrar.messenger())
    let instance = OtaPlugin()
    registrar.addMethodCallDelegate(instance, channel: channel)
    eventChannel.setStreamHandler(instance)
  }

  public func handle(_ call: FlutterMethodCall, result: @escaping FlutterResult) {
    let arguments = call.arguments as? [String: Any]

    switch call.method {
    case "init":
      userManager = JLBleManager.init()
      result("")
    case "startUpgrading":
      let address = arguments?["address"] as? String
      let filePath = arguments?["filePath"] as? String
      startUpgrading(address: address, filePath: filePath)
      result("")
    case "onOtaClose":
      onOtaClose()
      result("")
    default:
      result(FlutterMethodNotImplemented)
    }
  }

  public func onListen(withArguments arguments: Any?, eventSink events: @escaping FlutterEventSink) -> FlutterError? {
    eventSink = events
    return nil
  }

  public func onCancel(withArguments arguments: Any?) -> FlutterError? {
    eventSink = nil
    userManager?.flutterEventSink = nil
    return nil
  }

  private func startUpgrading(address: String?, filePath: String?) {
    if userManager?.mBleManagerState == CBManagerState.poweredOn {
      userManager?.flutterEventSink = eventSink
      userManager?.startScanBLE(address, filePath: filePath)
      DispatchQueue.main.asyncAfter(deadline: .now() + 10.0) {
        self.userManager?.stopScanBLE()
      }
    }
  }

  private func onOtaClose() {
    userManager?.releaseAllResources()
    userManager = nil
  }
}