import 'package:latlong2/latlong.dart';

import '../waypoint/flat_waypoint_list.dart';

const _distance = Distance(roundResult: false);

/// Gesamtdistanz/-dauer einer Mission (HTML-Demonstrator: computeStats()).
class MissionStats {
  const MissionStats({required this.distanceM, required this.durationSec});

  final double distanceM;
  final double durationSec;
}

/// Geteilt zwischen Plan- und Fly-Modus sowie der Warnungsberechnung (Doku
/// 3.9/3.10), die dieselben Werte fuer Zeit-/Reichweiten-Warnungen braucht.
MissionStats computeMissionStats(List<Waypoint> waypoints) {
  var totalDist = 0.0;
  var totalDur = 0.0;
  for (var i = 0; i < waypoints.length - 1; i++) {
    final a = LatLng(waypoints[i].lat, waypoints[i].lon);
    final b = LatLng(waypoints[i + 1].lat, waypoints[i + 1].lon);
    final d = _distance(a, b);
    totalDist += d;
    totalDur += d / waypoints[i + 1].speedMs;
  }
  return MissionStats(distanceM: totalDist, durationSec: totalDur);
}