import 'package:flutter/services.dart';

/// Thin Dart wrapper over the native DJI Mobile SDK bridge.
///
/// Mirrors the channels defined in `DjiSdkBridge.kt` (+ its per-subsystem
/// helpers):
///  * method channel `dji_msdk/methods` for imperative calls
///  * event  channel `dji_msdk/events`  for the SDK's async updates
///
/// Every method returns cleanly whether or not a product is connected; the
/// native side answers with a typed error the UI can surface. The event stream
/// carries maps keyed by `type`: `registration`, `connection`, `identity`,
/// `telemetry` (the batched snapshot — see `TelemetryReducer`), `camera`,
/// `exposure`, `histogram`, `diagnostics`, `mission`, `key`, `mediaList`, `mediaDownload`,
/// `djiAccount`, `productProfile`, `database`, `init`.
class DjiService {
  static const MethodChannel _methods = MethodChannel('dji_msdk/methods');
  static const EventChannel _events = EventChannel('dji_msdk/events');

  Stream<Map<String, dynamic>> events() {
    return _events
        .receiveBroadcastStream()
        .map((dynamic e) => Map<String, dynamic>.from(e as Map));
  }

  // ── SDK / registration / connection ─────────────────────────────────────────
  Future<String> getSdkVersion() async =>
      await _methods.invokeMethod<String>('getSdkVersion') ?? 'unknown';

  Future<void> registerApp() => _methods.invokeMethod<void>('registerApp');

  Future<bool> startConnection() async =>
      await _methods.invokeMethod<bool>('startConnection') ?? false;

  Future<void> stopConnection() => _methods.invokeMethod<void>('stopConnection');

  Future<Map<String, dynamic>> getProductInfo() async {
    final dynamic info = await _methods.invokeMethod('getProductInfo');
    return Map<String, dynamic>.from(info as Map);
  }

  /// The raw capability map `ProductProfile.fromBridge` consumes. The same map
  /// arrives unasked as a `productProfile` event on connect and component change.
  Future<Map<String, dynamic>> getProductProfile() async {
    final dynamic profile = await _methods.invokeMethod('getProductProfile');
    return Map<String, dynamic>.from(profile as Map);
  }

  // ── Flight controller commands ──────────────────────────────────────────────
  Future<void> takeOff() => _methods.invokeMethod<void>('takeOff');

  /// Take-off that records the spot visually, so RTH lands back on it.
  Future<void> precisionTakeOff() => _methods.invokeMethod<void>('precisionTakeOff');
  Future<void> land() => _methods.invokeMethod<void>('land');
  Future<void> confirmLanding() => _methods.invokeMethod<void>('confirmLanding');
  Future<void> cancelLanding() => _methods.invokeMethod<void>('cancelLanding');
  Future<void> startGoHome() => _methods.invokeMethod<void>('startGoHome');
  Future<void> cancelGoHome() => _methods.invokeMethod<void>('cancelGoHome');

  /// Answers the smart-RTH countdown (`goHome.smartRTHState == COUNTING_DOWN`):
  /// true flies home now, false cancels it.
  Future<void> confirmSmartRTH(bool goHome) =>
      _methods.invokeMethod<void>('confirmSmartRTH', <String, dynamic>{'value': goHome});
  Future<void> setHomeToCurrent() => _methods.invokeMethod<void>('setHomeToCurrent');

  /// Moves the home point (the RTH target dialog's "Current Position" = the pilot).
  Future<void> setHomeLocation(double latitude, double longitude) =>
      _methods.invokeMethod<void>('setHomeLocation', <String, dynamic>{'latitude': latitude, 'longitude': longitude});

  /// Starts compass calibration; `telemetry.compassCalibrationState` then walks
  /// HORIZONTAL → VERTICAL → SUCCESSFUL / FAILED as the pilot rotates the aircraft.
  Future<void> startCompassCalibration() => _methods.invokeMethod<void>('startCompassCalibration');
  Future<void> stopCompassCalibration() => _methods.invokeMethod<void>('stopCompassCalibration');

  // ── Calibration & maintenance (plan P6b, `CalibrationBridge.kt`) ────────────
  // Progress arrives in the `calibration` telemetry group (`CalibrationState`).

  /// Every IMU, or only [index]. There is no stop: it runs to the end.
  Future<void> startIMUCalibration({int? index}) =>
      _methods.invokeMethod<void>('startIMUCalibration', <String, dynamic>{if (index != null) 'index': index});
  Future<void> startGravityCenterCalibration() => _methods.invokeMethod<void>('startGravityCenterCalibration');
  Future<void> stopGravityCenterCalibration() => _methods.invokeMethod<void>('stopGravityCenterCalibration');
  Future<void> startPropellerCalibration() => _methods.invokeMethod<void>('startPropellerCalibration');
  Future<void> stopPropellerCalibration() => _methods.invokeMethod<void>('stopPropellerCalibration');

  /// Manual-focus lens calibration (interchangeable-lens cameras).
  Future<void> startLensCalibration() => _methods.invokeMethod<void>('startLensCalibration');
  Future<void> stopLensCalibration() => _methods.invokeMethod<void>('stopLensCalibration');

  /// Sensor dedusting: enter the mode, clean (lens off), leave it.
  Future<void> initSensorCleaning() => _methods.invokeMethod<void>('initSensorCleaning');
  Future<void> startSensorCleaning() => _methods.invokeMethod<void>('startSensorCleaning');
  Future<void> exitSensorCleaning() => _methods.invokeMethod<void>('exitSensorCleaning');

  /// Remote-controller calibration step: `MIDDLE` → `LIMITS` → `QUIT`.
  Future<void> setRcCalibrationStep(String step) =>
      _methods.invokeMethod<void>('setRcCalibrationStep', <String, dynamic>{'step': step});

  /// Streams the sticks and dials into `calibration.rcHardware` while on.
  Future<void> watchRcHardware(bool on) => _methods.invokeMethod<void>('watchRcHardware', <String, dynamic>{'on': on});

  /// Starts the flight controller's built-in simulator at [latitude]/[longitude]
  /// (developer only; propellers off). `telemetry.simulatorActive` reflects it.
  Future<void> startSimulator({required double latitude, required double longitude, int satellites = 12}) =>
      _methods.invokeMethod<void>('startSimulator', <String, dynamic>{
        'latitude': latitude,
        'longitude': longitude,
        'satelliteCount': satellites,
        'updateFrequency': 10,
      });
  Future<void> stopSimulator() => _methods.invokeMethod<void>('stopSimulator');

  // ── Flight settings (Safety / Control) ──────────────────────────────────────
  Future<void> setMaxFlightHeight(int m) =>
      _methods.invokeMethod<void>('setMaxFlightHeight', <String, dynamic>{'value': m});
  Future<void> setMaxFlightRadius(int m) =>
      _methods.invokeMethod<void>('setMaxFlightRadius', <String, dynamic>{'value': m});
  Future<void> setMaxRadiusEnabled(bool on) =>
      _methods.invokeMethod<void>('setMaxRadiusEnabled', <String, dynamic>{'value': on});
  Future<void> setGoHomeHeight(int m) =>
      _methods.invokeMethod<void>('setGoHomeHeight', <String, dynamic>{'value': m});
  Future<void> setNoviceMode(bool on) =>
      _methods.invokeMethod<void>('setNoviceMode', <String, dynamic>{'value': on});
  Future<void> setObstacleAvoidance(bool on) =>
      _methods.invokeMethod<void>('setObstacleAvoidance', <String, dynamic>{'value': on});

  // ── KeyManager (generic simple values) ──────────────────────────────────────
  /// Reads one SDK key. Enums come back as their name, arrays as lists.
  Future<Object?> getKey(DjiKey key) => _methods.invokeMethod<Object?>('getKey', key.args);

  /// Writes one SDK key; [value] is coerced natively to the key's Java type
  /// (an enum by name, a number to the exact width).
  Future<void> setKey(DjiKey key, Object? value) =>
      _methods.invokeMethod<void>('setKey', <String, dynamic>{...key.args, 'value': value});

  Future<bool> isKeySupported(DjiKey key) async =>
      await _methods.invokeMethod<bool>('isKeySupported', key.args) ?? false;

  /// Subscribes to a key: its current value and every change arrive as `key`
  /// events whose `id` is the string returned here. Idempotent per key.
  Future<String> listenKey(DjiKey key) async =>
      await _methods.invokeMethod<String>('listenKey', key.args) ?? key.id;

  /// Runs an action key that takes no arguments (`START_PAIRING`, …).
  Future<void> performKeyAction(DjiKey key) => _methods.invokeMethod<void>('performKeyAction', key.args);

  Future<void> cancelKey(String id) => _methods.invokeMethod<void>('cancelKey', <String, dynamic>{'id': id});

  // ── Camera ──────────────────────────────────────────────────────────────────
  /// mode: `photo` | `video` | `mediaDownload` | `playback`
  Future<void> setCameraMode(String mode) =>
      _methods.invokeMethod<void>('setCameraMode', <String, dynamic>{'mode': mode});
  Future<void> startShootPhoto() => _methods.invokeMethod<void>('startShootPhoto');
  Future<void> stopShootPhoto() => _methods.invokeMethod<void>('stopShootPhoto');
  Future<void> startRecordVideo() => _methods.invokeMethod<void>('startRecordVideo');
  Future<void> stopRecordVideo() => _methods.invokeMethod<void>('stopRecordVideo');

  /// mode: SINGLE | HDR | BURST | AEB | INTERVAL | PANORAMA
  Future<void> setShootPhotoMode(String mode) =>
      _methods.invokeMethod<void>('setShootPhotoMode', <String, dynamic>{'mode': mode});

  /// program: `auto` (PROGRAM) | `pro` (MANUAL)
  Future<void> setExposureProgram(String program) =>
      _methods.invokeMethod<void>('setExposureProgram', <String, dynamic>{'program': program});
  Future<void> setISO(String value) =>
      _methods.invokeMethod<void>('setISO', <String, dynamic>{'value': value});
  Future<void> setShutterSpeed(String value) =>
      _methods.invokeMethod<void>('setShutterSpeed', <String, dynamic>{'value': value});
  Future<void> setAperture(String value) =>
      _methods.invokeMethod<void>('setAperture', <String, dynamic>{'value': value});
  Future<void> setEV(String value) =>
      _methods.invokeMethod<void>('setEV', <String, dynamic>{'value': value});
  Future<void> setWhiteBalance(String value) =>
      _methods.invokeMethod<void>('setWhiteBalance', <String, dynamic>{'value': value});
  /// Erases the card. location: `SDCARD` | `INTERNAL_STORAGE`
  Future<void> formatStorage({String location = 'SDCARD'}) =>
      _methods.invokeMethod<void>('formatStorage', <String, dynamic>{'location': location});
  Future<void> setHistogramEnabled(bool on) =>
      _methods.invokeMethod<void>('setHistogramEnabled', <String, dynamic>{'value': on});

  /// One simple camera setting by its `cameraSettings` id (`photoAspectRatio`,
  /// `exposureMode`, `aeLock`, …) — see the table in `CameraBridge.kt`. [value]
  /// is the SDK enum name, or a bool.
  Future<void> setCameraValue(String id, Object value) =>
      _methods.invokeMethod<void>('setCameraValue', <String, dynamic>{'id': id, 'value': value});

  /// resolution / frameRate: SDK enum names (`RESOLUTION_3840x2160`, `FRAME_RATE_30_FPS`).
  Future<void> setVideoResolutionAndFrameRate(String resolution, String frameRate) =>
      _methods.invokeMethod<void>('setVideoResolutionAndFrameRate', <String, dynamic>{
        'resolution': resolution,
        'frameRate': frameRate,
      });

  /// Interval shooting: [count] photos (255 = until stopped) every [seconds].
  Future<void> setPhotoTimeInterval({required int count, required int seconds}) =>
      _methods.invokeMethod<void>('setPhotoTimeInterval', <String, dynamic>{'count': count, 'seconds': seconds});

  /// The picture style, each −3…+3 on most cameras.
  Future<void> setPictureStyle({required int sharpness, required int contrast, required int saturation}) =>
      _methods.invokeMethod<void>('setPictureStyle', <String, dynamic>{
        'sharpness': sharpness,
        'contrast': contrast,
        'saturation': saturation,
      });

  /// Tap-to-focus at x/y, each 0..1 across the live view.
  Future<void> setFocusTarget(double x, double y) =>
      _methods.invokeMethod<void>('setFocusTarget', <String, dynamic>{'x': x, 'y': y});

  /// Spot metering at x/y (0..1); switches the metering mode to SPOT first.
  Future<void> setSpotMeteringTarget(double x, double y) =>
      _methods.invokeMethod<void>('setSpotMeteringTarget', <String, dynamic>{'x': x, 'y': y});

  /// Optical zoom while a T / W button is held. direction: `in` | `out`.
  Future<void> startContinuousZoom(String direction) =>
      _methods.invokeMethod<void>('startContinuousZoom', <String, dynamic>{'direction': direction});
  Future<void> stopContinuousZoom() => _methods.invokeMethod<void>('stopContinuousZoom');

  /// Hybrid or optical focal length, in the units `cameraSettings.zoom*` report.
  Future<void> setZoomFocalLength(int value) =>
      _methods.invokeMethod<void>('setZoomFocalLength', <String, dynamic>{'value': value});
  Future<void> setDigitalZoomFactor(double value) =>
      _methods.invokeMethod<void>('setDigitalZoomFactor', <String, dynamic>{'value': value});

  /// The camera's own "Reset camera settings".
  Future<void> restoreCameraDefaults() => _methods.invokeMethod<void>('restoreCameraDefaults');

  // ── Gimbal ──────────────────────────────────────────────────────────────────
  /// Absolute pitch in degrees (the pitch slider).
  Future<void> rotateGimbalPitch(double deg) =>
      _methods.invokeMethod<void>('rotateGimbalPitch', <String, dynamic>{'pitch': deg});

  /// Speed-mode rotation in °/s (drag on the video). The gimbal only keeps
  /// moving while this is repeated (10 Hz); send zero to stop. A null axis is
  /// left alone.
  Future<void> rotateGimbalSpeed({double? pitch, double? yaw}) =>
      _methods.invokeMethod<void>('rotateGimbalSpeed', <String, dynamic>{
        if (pitch != null) 'pitch': pitch,
        if (yaw != null) 'yaw': yaw,
      });

  /// mode: `YAW_FOLLOW` | `FPV` | `FREE`
  Future<void> setGimbalMode(String mode) =>
      _methods.invokeMethod<void>('setGimbalMode', <String, dynamic>{'mode': mode});

  /// Pitch and yaw back to centre.
  Future<void> resetGimbal() => _methods.invokeMethod<void>('resetGimbal');
  Future<void> resetGimbalYaw() => _methods.invokeMethod<void>('resetGimbalYaw');

  /// Nudges the gimbal's [axis] (`roll` | `pitch` | `yaw`) trim by [degrees].
  Future<void> fineTuneGimbal(String axis, double degrees) =>
      _methods.invokeMethod<void>('fineTuneGimbal', <String, dynamic>{'axis': axis, 'degrees': degrees});

  /// Auto-calibration; `telemetry.gimbal.calibrating` / `calibrationProgress` follow it.
  Future<void> startGimbalCalibration() => _methods.invokeMethod<void>('startGimbalCalibration');

  /// One `gimbalSettings` value by id (`pitchExtension`, `yawFollow`,
  /// `pitchSmoothing`, `yawMaxSpeed`, …) — see the table in `GimbalBridge.kt`.
  Future<void> setGimbalSetting(String id, Object value) =>
      _methods.invokeMethod<void>('setGimbalSetting', <String, dynamic>{'id': id, 'value': value});

  /// The controller tuning values back to their defaults.
  Future<void> resetGimbalControlParameters() => _methods.invokeMethod<void>('resetGimbalControlParameters');

  // ── Missions ────────────────────────────────────────────────────────────────
  /// Loads and uploads a waypoint mission — `WaypointMissionSpec.toBridge()`'s
  /// map (see `MissionBridge.kt`). Resolves once every waypoint is on the
  /// aircraft; progress arrives as `mission` events with `operator: 'waypoint'`.
  Future<void> uploadWaypointMission(Map<String, Object?> mission) =>
      _methods.invokeMethod<void>('uploadWaypointMission', mission);
  Future<void> cancelWaypointUpload() => _methods.invokeMethod<void>('cancelWaypointUpload');

  /// The operator's `WaypointMissionState` name; also re-published as an event.
  Future<String?> getWaypointMissionState() => _methods.invokeMethod<String>('getWaypointMissionState');
  Future<void> startWaypointMission() => _methods.invokeMethod<void>('startWaypointMission');
  Future<void> stopWaypointMission() => _methods.invokeMethod<void>('stopWaypointMission');
  Future<void> pauseWaypointMission() => _methods.invokeMethod<void>('pauseWaypointMission');
  Future<void> resumeWaypointMission() => _methods.invokeMethod<void>('resumeWaypointMission');

  /// Changes the cruise speed of the mission in flight (m/s, −15…15).
  Future<void> setWaypointAutoFlightSpeed(double speed) =>
      _methods.invokeMethod<void>('setWaypointAutoFlightSpeed', <String, dynamic>{'speed': speed});

  /// Rect is normalized 0..1 in the live view. mode: TRACE|PROFILE|SPOTLIGHT|QUICK_SHOT
  Future<void> startActiveTrack(
    double x,
    double y,
    double w,
    double h, {
    String mode = 'TRACE',
  }) =>
      _methods.invokeMethod<void>('startActiveTrack', <String, dynamic>{
        'x': x,
        'y': y,
        'w': w,
        'h': h,
        'mode': mode,
      });
  Future<void> stopActiveTrack() => _methods.invokeMethod<void>('stopActiveTrack');

  /// Answers the operator's WAITING_FOR_CONFIRMATION: yes follows the subject, no drops it.
  Future<void> acceptActiveTrackConfirmation() => _methods.invokeMethod<void>('acceptActiveTrackConfirmation');
  Future<void> rejectActiveTrackConfirmation() => _methods.invokeMethod<void>('rejectActiveTrackConfirmation');

  /// mode: TRACE | PROFILE | SPOTLIGHT | SPOTLIGHT_PRO, while tracking.
  Future<void> switchActiveTrackMode(String mode) =>
      _methods.invokeMethod<void>('switchActiveTrackMode', <String, dynamic>{'mode': mode});

  /// Lets Trace fly backwards ahead of a subject walking towards the aircraft.
  Future<void> setActiveTrackRetreat(bool on) =>
      _methods.invokeMethod<void>('setActiveTrackRetreat', <String, dynamic>{'on': on});
  Future<bool?> getActiveTrackRetreat() => _methods.invokeMethod<bool>('getActiveTrackRetreat');

  /// Lets the aircraft look for subjects itself; they arrive in `tracking.subjects`.
  Future<void> setActiveTrackAutoSensing(bool on) =>
      _methods.invokeMethod<void>('setActiveTrackAutoSensing', <String, dynamic>{'on': on});

  /// Follows the auto-sensed subject with operator index [index].
  Future<void> startActiveTrackSubject(int index, {String mode = 'TRACE'}) =>
      _methods.invokeMethod<void>('startActiveTrackSubject', <String, dynamic>{'index': index, 'mode': mode});

  // ── TapFly ──────────────────────────────────────────────────────────────────
  /// Flies towards the point [x], [y] (0..1 across the live view).
  /// mode: FORWARD | BACKWARD | FREE; speed in m/s.
  Future<void> startTapFly(double x, double y, {String mode = 'FORWARD', double speed = 5, bool avoidance = true}) =>
      _methods.invokeMethod<void>('startTapFly', <String, dynamic>{
        'x': x,
        'y': y,
        'mode': mode,
        'speed': speed,
        'avoidance': avoidance,
      });
  Future<void> stopTapFly() => _methods.invokeMethod<void>('stopTapFly');
  Future<void> setTapFlySpeed(double speed) => _methods.invokeMethod<void>('setTapFlySpeed', <String, dynamic>{'speed': speed});
  Future<void> resetTapFlyHeading() => _methods.invokeMethod<void>('resetTapFlyHeading');

  // ── Virtual sticks (plan P8) ────────────────────────────────────────────────
  /// Puts the flight controller in (or out of) virtual-stick mode; while on, the
  /// native side streams the last [sendVirtualStick] at 25 Hz, or zeros once it
  /// is more than 300 ms old.
  Future<void> setVirtualStickEnabled(bool on) =>
      _methods.invokeMethod<void>('setVirtualStickEnabled', <String, dynamic>{'on': on});

  /// Body-frame velocities (m/s, forward / right / up positive) and yaw rate (°/s, clockwise).
  Future<void> sendVirtualStick({required double forward, required double right, required double yaw, required double up}) =>
      _methods.invokeMethod<void>('sendVirtualStick', <String, dynamic>{'forward': forward, 'right': right, 'yaw': yaw, 'up': up});

  // ── Sensing distances (plan P8) ─────────────────────────────────────────────
  /// `{avoidance: {Horizontal, Upward, Downward}, perception: {…}}` in metres;
  /// a direction the aircraft does not support reads null.
  Future<Map<String, dynamic>> getSensingDistances() async {
    final dynamic m = await _methods.invokeMethod('getSensingDistances');
    return Map<String, dynamic>.from(m as Map);
  }

  /// Where the aircraft brakes for an obstacle in [direction] (`Horizontal` / `Upward` / `Downward`).
  Future<void> setAvoidanceDistance(String direction, double metres) =>
      _methods.invokeMethod<void>('setAvoidanceDistance', <String, dynamic>{'direction': direction, 'value': metres});

  /// How far the aircraft looks for obstacles in [direction].
  Future<void> setMaxPerceptionDistance(String direction, double metres) =>
      _methods.invokeMethod<void>('setMaxPerceptionDistance', <String, dynamic>{'direction': direction, 'value': metres});

  // ── Fly zones (plan P8) ─────────────────────────────────────────────────────
  /// GEO zones around the point, or around the aircraft when omitted.
  Future<List<Map<String, dynamic>>> getFlyZonesNearby({double? latitude, double? longitude}) async {
    final List<Object?>? l = await _methods.invokeMethod<List<Object?>>('getFlyZonesNearby', <String, dynamic>{
      if (latitude != null) 'latitude': latitude,
      if (longitude != null) 'longitude': longitude,
    });
    return <Map<String, dynamic>>[for (final Object? z in l ?? const <Object?>[]) if (z is Map) Map<String, dynamic>.from(z)];
  }

  /// Ids of the authorization zones unlocked on the connected aircraft.
  Future<List<int>> getUnlockedFlyZones() async {
    final List<Object?>? l = await _methods.invokeMethod<List<Object?>>('getUnlockedFlyZones');
    return <int>[for (final Object? id in l ?? const <Object?>[]) if (id is int) id];
  }

  /// Self-unlocks an authorization zone; needs a logged-in DJI account.
  Future<void> unlockAuthorizationFlyZone(int id) =>
      _methods.invokeMethod<void>('unlockAuthorizationFlyZone', <String, dynamic>{'id': id});

  /// The aircraft's licences (custom unlock zones): `{supported, zones: [...]}`.
  Future<Map<String, dynamic>> getFlyZoneLicences() async {
    final dynamic m = await _methods.invokeMethod('getFlyZoneLicences');
    return Map<String, dynamic>.from(m as Map);
  }

  Future<void> setFlyZoneLicenceEnabled(int id, bool enabled) =>
      _methods.invokeMethod<void>('setFlyZoneLicenceEnabled', <String, dynamic>{'id': id, 'enabled': enabled});

  /// Downloads the logged-in DJI account's licences and writes them to the aircraft.
  Future<void> syncFlyZoneLicences() => _methods.invokeMethod<void>('syncFlyZoneLicences');

  Future<void> deleteAllFlyZoneLicences() => _methods.invokeMethod<void>('deleteAllFlyZoneLicences');

  /// `{basicVersion, basicState, preciseVersion, preciseState}`; unknown parts are null.
  Future<Map<String, dynamic>> getFlyZoneDatabase() async {
    final dynamic m = await _methods.invokeMethod('getFlyZoneDatabase');
    return Map<String, dynamic>.from(m as Map);
  }

  /// Downloads the basic GEO database; progress arrives as `flyZoneDbProgress` events.
  Future<void> startFlyZoneDatabaseUpgrade() => _methods.invokeMethod<void>('startFlyZoneDatabaseUpgrade');
  Future<void> stopFlyZoneDatabaseUpgrade() => _methods.invokeMethod<void>('stopFlyZoneDatabaseUpgrade');

  /// A DJI-Fly QuickShot by name (Dronie/Rocket/Circle/Helix/Boomerang/Asteroid).
  /// The native side maps each to the closest real operator or returns a typed
  /// "unsupported on this aircraft" error.
  Future<void> startQuickShot(String name) =>
      _methods.invokeMethod<void>('startQuickShot', <String, dynamic>{'name': name});

  // ── Media (MediaManager) ────────────────────────────────────────────────────
  Future<void> refreshMediaList() => _methods.invokeMethod<void>('refreshMediaList');
  Future<String?> fetchThumbnail(int index) =>
      _methods.invokeMethod<String>('fetchThumbnail', <String, dynamic>{'index': index});
  Future<String?> downloadMedia(int index) =>
      _methods.invokeMethod<String>('downloadMedia', <String, dynamic>{'index': index});
  Future<void> deleteMedia(int index) =>
      _methods.invokeMethod<void>('deleteMedia', <String, dynamic>{'index': index});

  // ── DJI account (optional) ──────────────────────────────────────────────────
  Future<void> djiLogin() => _methods.invokeMethod<void>('djiLogin');
  Future<void> djiLogout() => _methods.invokeMethod<void>('djiLogout');
  Future<void> refreshDjiAccountState() => _methods.invokeMethod<void>('getDjiAccountState');
}

/// One MSDK V4 KeyManager key, as `KeyBridge.kt` addresses it.
///
/// [key] is the key class's constant name (`LOW_BATTERY_WARNING_THRESHOLD`) or
/// the raw parameter string; [index] picks the camera / gimbal / battery and
/// [subIndex] a camera lens.
class DjiKey {
  const DjiKey(this.component, this.key, {this.index = 0, this.subIndex});

  const DjiKey.flightController(String key) : this('FlightController', key);
  const DjiKey.flightAssistant(String key) : this('FlightAssistant', key);
  const DjiKey.camera(String key, {int index = 0, int? lens}) : this('Camera', key, index: index, subIndex: lens);
  const DjiKey.gimbal(String key, {int index = 0}) : this('Gimbal', key, index: index);
  const DjiKey.battery(String key, {int index = 0}) : this('Battery', key, index: index);
  const DjiKey.airLink(String key) : this('AirLink', key);
  const DjiKey.ocuSync(String key) : this('OcuSyncLink', key);
  const DjiKey.lightbridge(String key) : this('LightbridgeLink', key);
  const DjiKey.wifi(String key) : this('WiFiLink', key);
  const DjiKey.remoteController(String key) : this('RemoteController', key);
  const DjiKey.product(String key) : this('Product', key);

  final String component;
  final String key;
  final int index;
  final int? subIndex;

  /// The id `listenKey` answers with and `key` events carry.
  String get id => '$component/$key/$index/${subIndex ?? 'null'}';

  Map<String, dynamic> get args => <String, dynamic>{
        'component': component,
        'key': key,
        'index': index,
        if (subIndex != null) 'subIndex': subIndex,
      };

  @override
  bool operator ==(Object other) => other is DjiKey && other.id == id;

  @override
  int get hashCode => id.hashCode;

  @override
  String toString() => id;
}