PilotVault/Fly App/lib/fly/modes/waypoint_mission.dart

import 'dart:math' as math;

import 'package:flutter/foundation.dart';
import 'package:latlong2/latlong.dart' show LatLng;

import '../hud_geometry.dart';

/// A Waypoints mission as the pilot edits it (plan P7, GO 4's Waypoints 2.0
/// editor), and its translation into what MSDK V4's `WaypointMissionOperator`
/// takes.
///
/// The editor works in GO 4's terms — per-point heading Route / Custom / POI,
/// "aim the gimbal at the POI", a camera action, a hover — and [toBridge]
/// resolves them into the V1 mission: a heading per waypoint and the turn
/// direction to it, a gimbal pitch on every waypoint once any is set, and the
/// STAY / photo / record actions. MSDK V1 has one mission-wide point of
/// interest, so a per-point POI becomes that point's computed heading.
///
/// Pure and immutable, so the whole translation and [validate] are unit-tested.

/// What the camera does on arrival at a waypoint.
enum WaypointCameraAction {
  none('None'),
  photo('Photo'),
  startRecord('Start recording'),
  stopRecord('Stop recording');

  const WaypointCameraAction(this.label);
  final String label;
}

/// Where a waypoint points the aircraft, when the route heading is [RouteHeadingMode.perPoint].
enum WaypointHeading {
  /// Along the route, towards the next waypoint.
  route('Route'),
  custom('Custom'),

  /// At the waypoint's linked POI.
  poi('POI');

  const WaypointHeading(this.label);
  final String label;
}

/// The mission-wide heading ("All Waypoint Direction").
enum RouteHeadingMode {
  auto('Route', 'AUTO'),
  initial('Initial direction', 'USING_INITIAL_DIRECTION'),
  rc('Manual (RC)', 'CONTROL_BY_REMOTE_CONTROLLER'),
  perPoint('Per waypoint', 'USING_WAYPOINT_HEADING'),
  poi('Towards POI', 'TOWARD_POINT_OF_INTEREST');

  const RouteHeadingMode(this.label, this.sdk);
  final String label;
  final String sdk;
}

/// "Task Finished".
enum RouteFinishAction {
  hover('Hover', 'NO_ACTION'),
  goHome('Return to Home', 'GO_HOME'),
  land('Land', 'AUTO_LAND'),
  firstWaypoint('Back to first waypoint', 'GO_FIRST_WAYPOINT');

  const RouteFinishAction(this.label, this.sdk);
  final String label;
  final String sdk;
}

/// "Route type": straight legs that stop at each waypoint, or curves through them.
enum RoutePathMode {
  straight('Straight', 'NORMAL'),
  curved('Curved', 'CURVED');

  const RoutePathMode(this.label, this.sdk);
  final String label;
  final String sdk;
}

/// How the aircraft gets to the first waypoint.
enum RouteGotoFirst {
  /// Climbs to the waypoint's altitude first if it is higher.
  safely('Climb first', 'SAFELY'),
  pointToPoint('Straight line', 'POINT_TO_POINT');

  const RouteGotoFirst(this.label, this.sdk);
  final String label;
  final String sdk;
}

/// A point of interest waypoints can face, and aim the gimbal at.
@immutable
class MissionPoi {
  const MissionPoi({required this.id, required this.at, this.height = 0});

  final String id;
  final LatLng at;

  /// Height of the subject above the take-off point, for aiming the gimbal.
  final double height;

  MissionPoi copyWith({LatLng? at, double? height}) => MissionPoi(id: id, at: at ?? this.at, height: height ?? this.height);

  Map<String, Object?> toJson() => <String, Object?>{'id': id, 'lat': at.latitude, 'lon': at.longitude, 'height': height};

  static MissionPoi fromJson(Map<String, dynamic> j) => MissionPoi(
        id: j['id'] as String,
        at: LatLng((j['lat'] as num).toDouble(), (j['lon'] as num).toDouble()),
        height: (j['height'] as num?)?.toDouble() ?? 0,
      );

  @override
  bool operator ==(Object other) => other is MissionPoi && other.id == id && other.at == at && other.height == height;

  @override
  int get hashCode => Object.hash(id, at, height);
}

/// One waypoint.
@immutable
class WaypointSpec {
  const WaypointSpec({
    required this.at,
    this.altitude = 50,
    this.speed,
    this.heading = WaypointHeading.route,
    this.customHeading = 0,
    this.gimbalPitch,
    this.gimbalAimPoi = false,
    this.action = WaypointCameraAction.none,
    this.hoverSeconds = 0,
    this.poiId,
    this.turnRadius = 0.2,
  });

  final LatLng at;

  /// Metres above the take-off point.
  final double altitude;

  /// m/s from here to the next waypoint; null flies the route's cruise speed.
  final double? speed;

  final WaypointHeading heading;

  /// −180…180°, for [WaypointHeading.custom].
  final int customHeading;

  /// Degrees; null keeps whatever the previous waypoint set.
  final double? gimbalPitch;

  /// Aim the gimbal at the linked POI instead of [gimbalPitch].
  final bool gimbalAimPoi;

  final WaypointCameraAction action;

  /// Seconds to hover on arrival, before the camera action.
  final int hoverSeconds;

  /// The linked [MissionPoi.id].
  final String? poiId;

  /// Metres; only curved routes use it.
  final double turnRadius;

  static const Object _keep = Object();

  /// Nullable fields take [_keep] to stay unchanged, so `null` can clear them.
  WaypointSpec copyWith({
    LatLng? at,
    double? altitude,
    Object? speed = _keep,
    WaypointHeading? heading,
    int? customHeading,
    Object? gimbalPitch = _keep,
    bool? gimbalAimPoi,
    WaypointCameraAction? action,
    int? hoverSeconds,
    Object? poiId = _keep,
    double? turnRadius,
  }) =>
      WaypointSpec(
        at: at ?? this.at,
        altitude: altitude ?? this.altitude,
        // Any num: an int literal (`?? -30`) arrives here as an int.
        speed: identical(speed, _keep) ? this.speed : (speed as num?)?.toDouble(),
        heading: heading ?? this.heading,
        customHeading: customHeading ?? this.customHeading,
        gimbalPitch: identical(gimbalPitch, _keep) ? this.gimbalPitch : (gimbalPitch as num?)?.toDouble(),
        gimbalAimPoi: gimbalAimPoi ?? this.gimbalAimPoi,
        action: action ?? this.action,
        hoverSeconds: hoverSeconds ?? this.hoverSeconds,
        poiId: identical(poiId, _keep) ? this.poiId : poiId as String?,
        turnRadius: turnRadius ?? this.turnRadius,
      );

  Map<String, Object?> toJson() => <String, Object?>{
        'lat': at.latitude,
        'lon': at.longitude,
        'altitude': altitude,
        if (speed != null) 'speed': speed,
        'heading': heading.name,
        'customHeading': customHeading,
        if (gimbalPitch != null) 'gimbalPitch': gimbalPitch,
        if (gimbalAimPoi) 'gimbalAimPoi': true,
        'action': action.name,
        if (hoverSeconds > 0) 'hoverSeconds': hoverSeconds,
        if (poiId != null) 'poi': poiId,
        'turnRadius': turnRadius,
      };

  static WaypointSpec fromJson(Map<String, dynamic> j) => WaypointSpec(
        at: LatLng((j['lat'] as num).toDouble(), (j['lon'] as num).toDouble()),
        altitude: (j['altitude'] as num?)?.toDouble() ?? 50,
        speed: (j['speed'] as num?)?.toDouble(),
        heading: _byName(WaypointHeading.values, j['heading']) ?? WaypointHeading.route,
        customHeading: (j['customHeading'] as num?)?.toInt() ?? 0,
        gimbalPitch: (j['gimbalPitch'] as num?)?.toDouble(),
        gimbalAimPoi: j['gimbalAimPoi'] == true,
        action: _byName(WaypointCameraAction.values, j['action']) ?? WaypointCameraAction.none,
        hoverSeconds: (j['hoverSeconds'] as num?)?.toInt() ?? 0,
        poiId: j['poi'] as String?,
        turnRadius: (j['turnRadius'] as num?)?.toDouble() ?? 0.2,
      );

  @override
  bool operator ==(Object other) => other is WaypointSpec && mapEquals(other.toJson(), toJson());

  @override
  int get hashCode => Object.hashAll(toJson().values);
}

enum IssueLevel { warning, error }

/// Something wrong with a mission, optionally pinned to a waypoint (0-based).
@immutable
class MissionIssue {
  const MissionIssue.error(this.message, {this.point}) : level = IssueLevel.error;
  const MissionIssue.warning(this.message, {this.point}) : level = IssueLevel.warning;

  final IssueLevel level;
  final String message;
  final int? point;

  bool get blocks => level == IssueLevel.error;

  @override
  bool operator ==(Object other) => other is MissionIssue && other.level == level && other.message == message && other.point == point;

  @override
  int get hashCode => Object.hash(level, message, point);

  @override
  String toString() => '${level.name}: $message';
}

/// What [WaypointMissionSpec.validate] checks the route against: the
/// aircraft's own limits, when known.
@immutable
class MissionLimits {
  const MissionLimits({this.maxAltitude, this.maxRadius, this.home, this.gimbalMin = -90, this.gimbalMax = 30});

  /// The flight controller's altitude limit, m.
  final double? maxAltitude;

  /// The distance limit, m from home, when enabled.
  final double? maxRadius;
  final LatLng? home;
  final double gimbalMin;
  final double gimbalMax;
}

class WaypointMissionSpec {
  const WaypointMissionSpec({
    this.id = '',
    this.name = 'New route',
    this.points = const <WaypointSpec>[],
    this.pois = const <MissionPoi>[],
    this.cruiseSpeed = 8,
    this.headingMode = RouteHeadingMode.auto,
    this.finishAction = RouteFinishAction.goHome,
    this.pathMode = RoutePathMode.straight,
    this.exitOnSignalLost = true,
    this.gotoFirst = RouteGotoFirst.safely,
    this.repeatTimes = 1,
    this.updatedAt,
  });

  // ── MSDK 4.18 limits (`Waypoint` / `WaypointMission` constants) ────────────
  static const int maxPoints = 99;
  static const int minPoints = 2;
  static const double minAltitude = -200;

  /// The flight controller's ceiling, whatever the SDK constant says (it is FLT_MAX).
  static const double maxAltitudeSdk = 500;
  static const double minSpeed = 1;
  static const double maxSpeed = 15;
  static const double minTurnRadius = 0.2;
  static const double maxTurnRadius = 1000;

  /// Adjacent waypoints closer than this are refused.
  static const double minLeg = 0.5;

  /// …and further apart than this.
  static const double maxLeg = 2000;

  /// `STAY`'s parameter is milliseconds up to 32767.
  static const int maxHoverSeconds = 32;

  /// Below this the pre-start check warns about trees and buildings.
  static const double lowAltitude = 10;

  final String id;
  final String name;
  final List<WaypointSpec> points;
  final List<MissionPoi> pois;
  final double cruiseSpeed;
  final RouteHeadingMode headingMode;
  final RouteFinishAction finishAction;
  final RoutePathMode pathMode;

  /// True: on RC signal loss the mission ends and the aircraft does its
  /// signal-lost action. False: it finishes the route.
  final bool exitOnSignalLost;
  final RouteGotoFirst gotoFirst;
  final int repeatTimes;
  final DateTime? updatedAt;

  bool get isEmpty => points.isEmpty;

  MissionPoi? poi(String? id) {
    if (id == null) return null;
    for (final MissionPoi p in pois) {
      if (p.id == id) return p;
    }
    return null;
  }

  WaypointMissionSpec copyWith({
    String? id,
    String? name,
    List<WaypointSpec>? points,
    List<MissionPoi>? pois,
    double? cruiseSpeed,
    RouteHeadingMode? headingMode,
    RouteFinishAction? finishAction,
    RoutePathMode? pathMode,
    bool? exitOnSignalLost,
    RouteGotoFirst? gotoFirst,
    int? repeatTimes,
    DateTime? updatedAt,
  }) =>
      WaypointMissionSpec(
        id: id ?? this.id,
        name: name ?? this.name,
        points: points ?? this.points,
        pois: pois ?? this.pois,
        cruiseSpeed: cruiseSpeed ?? this.cruiseSpeed,
        headingMode: headingMode ?? this.headingMode,
        finishAction: finishAction ?? this.finishAction,
        pathMode: pathMode ?? this.pathMode,
        exitOnSignalLost: exitOnSignalLost ?? this.exitOnSignalLost,
        gotoFirst: gotoFirst ?? this.gotoFirst,
        repeatTimes: repeatTimes ?? this.repeatTimes,
        updatedAt: updatedAt ?? this.updatedAt,
      );

  // ── Geometry and estimates ────────────────────────────────────────────────

  /// 3-D length of each leg, m: leg i runs from point i to point i+1.
  List<double> get legs => <double>[
        for (int i = 0; i + 1 < points.length; i++) _dist3(points[i], points[i + 1]),
      ];

  static double _dist2(LatLng a, LatLng b) => HudGeometry.distance(a.latitude, a.longitude, b.latitude, b.longitude);

  static double _dist3(WaypointSpec a, WaypointSpec b) {
    final double h = _dist2(a.at, b.at), v = b.altitude - a.altitude;
    return math.sqrt(h * h + v * v);
  }

  /// The route's length, m, once through.
  double get length => legs.fold(0.0, (double s, double l) => s + l);

  double speedOf(int i) => (points[i].speed ?? cruiseSpeed).clamp(minSpeed, maxSpeed);

  /// A rough flight time for the route, s: each leg at its speed, the hovers,
  /// ~2 s per photo, and ~3 s to brake and accelerate at every straight-route stop.
  int get estimatedSeconds {
    if (points.length < 2) return 0;
    double t = 0;
    final List<double> l = legs;
    for (int i = 0; i < l.length; i++) {
      t += l[i] / speedOf(i);
    }
    for (final WaypointSpec p in points) {
      t += p.hoverSeconds;
      if (p.action == WaypointCameraAction.photo) t += 2;
    }
    if (pathMode == RoutePathMode.straight) t += 3.0 * (points.length - 2).clamp(0, maxPoints);
    return (t * repeatTimes.clamp(1, 255)).round();
  }

  // ── Resolution into the V1 mission ────────────────────────────────────────

  static int _signed(double bearing) {
    final int b = bearing.round() % 360;
    return b > 180 ? b - 360 : b;
  }

  static double _bearing(LatLng a, LatLng b) => HudGeometry.bearing(a.latitude, a.longitude, b.latitude, b.longitude);

  /// The heading each waypoint flies at, −180…180, when headings are per waypoint.
  List<int> resolvedHeadings() {
    final List<int> out = <int>[];
    for (int i = 0; i < points.length; i++) {
      final WaypointSpec p = points[i];
      final MissionPoi? poiAt = poi(p.poiId);
      switch (p.heading) {
        case WaypointHeading.custom:
          out.add(p.customHeading.clamp(-180, 180));
        case WaypointHeading.poi when poiAt != null:
          out.add(_signed(_bearing(p.at, poiAt.at)));
        case WaypointHeading.poi:
        case WaypointHeading.route:
          if (points.length < 2) {
            out.add(0);
          } else if (i + 1 < points.length) {
            out.add(_signed(_bearing(p.at, points[i + 1].at)));
          } else {
            out.add(_signed(_bearing(points[i - 1].at, p.at)));
          }
      }
    }
    return out;
  }

  /// The gimbal pitch at every waypoint, or null when no waypoint sets one
  /// (the pilot keeps the gimbal). A waypoint without its own pitch keeps the
  /// previous one's; leading ones take the first set value.
  List<double>? resolvedGimbal({double min = -90, double max = 30}) {
    final List<double?> own = <double?>[
      for (final WaypointSpec p in points) _ownPitch(p),
    ];
    final double? first = own.firstWhere((double? v) => v != null, orElse: () => null);
    if (first == null) return null;
    double last = first;
    return <double>[
      for (final double? v in own) (last = v ?? last).clamp(min, max).toDouble(),
    ];
  }

  double? _ownPitch(WaypointSpec p) {
    final MissionPoi? target = poi(p.poiId);
    if (p.gimbalAimPoi && target != null) {
      final double d = _dist2(p.at, target.at);
      final double drop = p.altitude - target.height;
      return d < 0.5 ? -90 : -math.atan2(drop, d) * 180 / math.pi;
    }
    return p.gimbalPitch;
  }

  /// The `uploadWaypointMission` payload for `MissionBridge.kt`: SDK enum
  /// names and resolved per-waypoint values.
  Map<String, Object?> toBridge({double gimbalMin = -90, double gimbalMax = 30}) {
    final bool perPoint = headingMode == RouteHeadingMode.perPoint;
    final List<int> headings = resolvedHeadings();
    final List<double>? pitch = resolvedGimbal(min: gimbalMin, max: gimbalMax);
    final bool curved = pathMode == RoutePathMode.curved;

    final List<Map<String, Object?>> wps = <Map<String, Object?>>[];
    int? previous;
    for (int i = 0; i < points.length; i++) {
      final WaypointSpec p = points[i];
      final int h = headings[i];
      // Turn the short way round from the previous waypoint's heading.
      String turn = 'CLOCKWISE';
      if (perPoint && previous != null) {
        final int delta = ((h - previous) % 360 + 360) % 360;
        if (delta > 180) turn = 'COUNTER_CLOCKWISE';
      }
      previous = h;
      wps.add(<String, Object?>{
        'lat': p.at.latitude,
        'lon': p.at.longitude,
        'altitude': p.altitude,
        if (perPoint) 'heading': h,
        'turnMode': turn,
        // 0 = the mission's auto flight speed.
        'speed': p.speed == null ? 0.0 : p.speed!.clamp(minSpeed, maxSpeed),
        'cornerRadius': curved ? p.turnRadius.clamp(minTurnRadius, maxTurnRadius) : minTurnRadius,
        if (pitch != null) 'gimbalPitch': pitch[i],
        'actions': <Map<String, Object?>>[
          if (p.hoverSeconds > 0) <String, Object?>{'type': 'STAY', 'param': (p.hoverSeconds.clamp(0, maxHoverSeconds) * 1000).clamp(0, 32767)},
          if (p.action == WaypointCameraAction.photo) const <String, Object?>{'type': 'START_TAKE_PHOTO', 'param': 0},
          if (p.action == WaypointCameraAction.startRecord) const <String, Object?>{'type': 'START_RECORD', 'param': 0},
          if (p.action == WaypointCameraAction.stopRecord) const <String, Object?>{'type': 'STOP_RECORD', 'param': 0},
        ],
      });
    }
    final MissionPoi? missionPoi = pois.isEmpty ? null : pois.first;
    return <String, Object?>{
      'waypoints': wps,
      'autoFlightSpeed': cruiseSpeed.clamp(minSpeed, maxSpeed),
      'maxFlightSpeed': maxSpeed,
      'finishedAction': finishAction.sdk,
      'headingMode': headingMode.sdk,
      'flightPathMode': pathMode.sdk,
      'gotoFirstWaypointMode': gotoFirst.sdk,
      'exitMissionOnRCSignalLost': exitOnSignalLost,
      'gimbalPitchRotation': pitch != null,
      'repeatTimes': repeatTimes.clamp(1, 255),
      if (headingMode == RouteHeadingMode.poi && missionPoi != null)
        'pointOfInterest': <String, Object?>{'lat': missionPoi.at.latitude, 'lon': missionPoi.at.longitude},
    };
  }

  // ── Validation ────────────────────────────────────────────────────────────

  /// Everything that would make the SDK refuse the mission (errors) or that
  /// the pilot should know before flying it (warnings).
  List<MissionIssue> validate([MissionLimits limits = const MissionLimits()]) {
    final List<MissionIssue> out = <MissionIssue>[];
    if (points.length < minPoints) out.add(const MissionIssue.error('Add at least 2 waypoints.'));
    if (points.length > maxPoints) out.add(const MissionIssue.error('A route can have at most $maxPoints waypoints.'));

    final double ceiling = math.min(maxAltitudeSdk, limits.maxAltitude ?? maxAltitudeSdk);
    for (int i = 0; i < points.length; i++) {
      final WaypointSpec p = points[i];
      final String n = 'Waypoint ${i + 1}';
      if (p.altitude > ceiling) {
        out.add(MissionIssue.error('$n is at ${p.altitude.round()} m, above the ${ceiling.round()} m altitude limit.', point: i));
      } else if (p.altitude < minAltitude) {
        out.add(MissionIssue.error('$n is too far below the take-off point.', point: i));
      } else if (p.altitude < lowAltitude) {
        out.add(MissionIssue.warning('$n is only ${p.altitude.round()} m above the take-off point.', point: i));
      }
      if (limits.maxRadius != null && limits.home != null && _dist2(limits.home!, p.at) > limits.maxRadius!) {
        out.add(MissionIssue.error('$n is beyond the ${limits.maxRadius!.round()} m distance limit.', point: i));
      }
      if (p.heading == WaypointHeading.poi && poi(p.poiId) == null && headingMode == RouteHeadingMode.perPoint) {
        out.add(MissionIssue.warning('$n faces a POI but none is linked: it flies along the route.', point: i));
      }
    }

    final List<double> l = legs;
    for (int i = 0; i < l.length; i++) {
      final double flat = _dist2(points[i].at, points[i + 1].at);
      if (flat < minLeg && (points[i].altitude - points[i + 1].altitude).abs() < minLeg) {
        out.add(MissionIssue.error('Waypoints ${i + 1} and ${i + 2} are on top of each other.', point: i + 1));
      } else if (flat > maxLeg) {
        out.add(MissionIssue.error('Waypoints ${i + 1} and ${i + 2} are more than 2 km apart.', point: i + 1));
      }
    }

    if (pathMode == RoutePathMode.curved) {
      for (int i = 0; i < l.length; i++) {
        final double sum = points[i].turnRadius + points[i + 1].turnRadius;
        if (sum >= _dist2(points[i].at, points[i + 1].at)) {
          out.add(MissionIssue.error('The turn radii of waypoints ${i + 1} and ${i + 2} overlap: make them smaller.', point: i + 1));
        }
      }
      if (points.any((WaypointSpec p) => p.action != WaypointCameraAction.none || p.hoverSeconds > 0)) {
        out.add(const MissionIssue.warning('A curved route flies through its waypoints without stopping: their actions and hovers are skipped.'));
      }
    }

    if (headingMode == RouteHeadingMode.poi && pois.isEmpty) {
      out.add(const MissionIssue.error('"Towards POI" needs a point of interest: add one on the map.'));
    }
    if (cruiseSpeed < minSpeed || cruiseSpeed > maxSpeed) {
      out.add(const MissionIssue.error('Cruise speed must be between 1 and 15 m/s.'));
    }
    return out;
  }

  // ── Storage (mission library, later the API Server) ───────────────────────

  static const int formatVersion = 1;

  Map<String, Object?> toJson() => <String, Object?>{
        'version': formatVersion,
        'id': id,
        'name': name,
        'points': <Map<String, Object?>>[for (final WaypointSpec p in points) p.toJson()],
        'pois': <Map<String, Object?>>[for (final MissionPoi p in pois) p.toJson()],
        'cruiseSpeed': cruiseSpeed,
        'headingMode': headingMode.name,
        'finishAction': finishAction.name,
        'pathMode': pathMode.name,
        'exitOnSignalLost': exitOnSignalLost,
        'gotoFirst': gotoFirst.name,
        'repeatTimes': repeatTimes,
        if (updatedAt != null) 'updatedAt': updatedAt!.toUtc().toIso8601String(),
      };

  static WaypointMissionSpec fromJson(Map<String, dynamic> j) => WaypointMissionSpec(
        id: j['id'] as String? ?? '',
        name: j['name'] as String? ?? 'Route',
        points: <WaypointSpec>[
          for (final Object? p in (j['points'] as List<Object?>? ?? const <Object?>[]))
            if (p is Map) WaypointSpec.fromJson(Map<String, dynamic>.from(p)),
        ],
        pois: <MissionPoi>[
          for (final Object? p in (j['pois'] as List<Object?>? ?? const <Object?>[]))
            if (p is Map) MissionPoi.fromJson(Map<String, dynamic>.from(p)),
        ],
        cruiseSpeed: (j['cruiseSpeed'] as num?)?.toDouble() ?? 8,
        headingMode: _byName(RouteHeadingMode.values, j['headingMode']) ?? RouteHeadingMode.auto,
        finishAction: _byName(RouteFinishAction.values, j['finishAction']) ?? RouteFinishAction.goHome,
        pathMode: _byName(RoutePathMode.values, j['pathMode']) ?? RoutePathMode.straight,
        exitOnSignalLost: j['exitOnSignalLost'] as bool? ?? true,
        gotoFirst: _byName(RouteGotoFirst.values, j['gotoFirst']) ?? RouteGotoFirst.safely,
        repeatTimes: (j['repeatTimes'] as num?)?.toInt() ?? 1,
        updatedAt: DateTime.tryParse(j['updatedAt'] as String? ?? ''),
      );
}

T? _byName<T extends Enum>(List<T> values, Object? name) {
  for (final T v in values) {
    if (v.name == name) return v;
  }
  return null;
}