Repository

using System;
using System.Collections.Generic;
using GeoCoordinatePortable;
using System.Text;

namespace ConsoleApp1
{
    public class Repository
    {
        private static List<Order> _orders;
        private static List<Courier> _couriers;
        private static HashSet<Guid> _guids;

        public Repository()
        {
            _orders = new List<Order>();
            _couriers = new List<Courier>();
        }

        public void AddCourier(Courier courier) =>
            _couriers.Add(courier);

        public static void AddOrder(double weight, GeoCoordinate source, GeoCoordinate destination)
        {
            Guid guid = Guid.NewGuid();
            while (_guids.Contains(guid))
                guid = Guid.NewGuid();
            _guids.Add(guid);
            _orders.Add(new Order(weight, source, destination, guid));
        }

        public static bool AssignCourier(Order order)
        {
            double minDist = double.MaxValue;
            foreach (var courier in _couriers)
            {
                if (courier.MaxAccWeightOfParcel >= order.Weight &&
                courier.CurrentPosition.GetDistanceTo(order.StartPoint) < minDist)
                    minDist = courier.CurrentPosition.GetDistanceTo(order.StartPoint);
            }

            foreach (var courier in _couriers)
            {
                if (courier.MaxAccWeightOfParcel >= order.Weight &&
                courier.CurrentPosition.GetDistanceTo(order.StartPoint) == minDist)
                {
                    order.StartTime = DateTime.Now;
                    courier.IsAvailable = false;
                    order.CourierID = courier.ID;
                    return true;
                }
            }
            return false;
        }

        public static void CompleteOrder(Order order)
        {
            order.EndTime = DateTime.Now;
            foreach (var courier in _couriers)
                if (courier.ID == order.CourierID)
                {
                    courier.IsAvailable = true;
                    courier.CurrentPosition = order.EndPoint;
                }
        }

    }
}