sharee.bike-App/TINKLib/Model/Bikes/BikeCollectionFilter.cs

using System.Collections.Generic;
using System.Linq;
using TINK.Model.Bike;

using BikeInfo = TINK.Model.Bike.BC.BikeInfo;

namespace TINK.Model
{
    public static class BikeCollectionFilter
    {
        /// <summary> Filters bikes by station. </summary>
        /// <param name="bikesAtAnyStation">Bikes available, requested and/ or occupied bikes to filter.</param>
        /// <param name="selectedStation">Id of station, might be null</param>
        /// <returns>BikeCollection holding bikes at given station or empty BikeCollection, if there are no bikes.</returns>
        public static BikeCollection GetAtStation(
            this BikeCollection bikesAtAnyStation,
            string selectedStation)
        {
            return new BikeCollection(bikesAtAnyStation?
                .Where(bike => !string.IsNullOrEmpty(selectedStation) && bike.CurrentStation == selectedStation)
                .ToDictionary(x => x.Id) ?? new Dictionary<string, BikeInfo>());
        }

        /// <summary> Filters bikes by bike type. </summary>
        /// <param name="bcAndLockItBikes">Bikes available, requested and/ or occupied bikes to filter.</param>
        /// <returns>BikeCollection holding LockIt-bikes empty BikeCollection, if there are no LockIt-bikes.</returns>
        public static BikeCollection GetLockIt(this BikeCollection bcAndLockItBikes)
        {
            return new BikeCollection(bcAndLockItBikes?
                .Where(bike => bike is Bike.BluetoothLock.BikeInfo)                
                .ToDictionary(x => x.Id) ?? new Dictionary<string, BikeInfo>());
        }
    }
}