sharee.bike-App/SharedBusinessLogic/ViewModel/Map/CargoCitybikeToggleViewModel.cs

using System.Collections.Generic;
using System.Linq;
using ShareeBike.Model;
using ShareeBike.Model.Connector;
using ShareeBike.Model.Connector.Filter;
using Xamarin.Forms;

namespace ShareeBike.ViewModel.Map
{
	/// <remarks> Old name: MapPageFilter. </remarks>
	public class CargoCitybikeToggleViewModel : ICargoCitybikeToggleViewModel
	{
		/// <summary> Constructs a map page filter view model object from values.</summary>
		/// <param name="currentFilter">Filters and options dictionary.</param>
		public CargoCitybikeToggleViewModel(IGroupFilterMapPage currentFilter)
		{
			FilterDictionary = currentFilter ?? new GroupFilterMapPage();
		}

		/// <summary> Gets the filter values.</summary>
		public IGroupFilterMapPage FilterDictionary { get; }

		/// <summary> Gets the activated filter.</summary>
		public string CurrentFilter
		{
			get
			{
				return FilterDictionary.FirstOrDefault(x => x.Value == FilterState.On).Key ?? string.Empty;
			}
		}

		/// <summary> Gets value whether ShareeBike is enabled or not. </summary>
		public bool IsCargoEnabled => !string.IsNullOrEmpty(CurrentFilter) && CurrentFilter.GetBikeCategory() != FilterHelper.CARGOBIKE;

		/// <summary> Gets color of the ShareeBike button. </summary>
		public Color CargoColor => CurrentFilter.GetBikeCategory() == FilterHelper.CARGOBIKE ? Color.White : Color.FromRgba(0, 0, 0, 0);
		public Color NoCargoColor => CurrentFilter.GetBikeCategory() == FilterHelper.CARGOBIKE ? Color.FromRgb(210, 17, 20) : Color.White;
		/// <summary> Gets value whether Citybike is enabled or not. </summary>
		public bool IsCitybikeEnabled => !string.IsNullOrEmpty(CurrentFilter) && CurrentFilter.GetBikeCategory() != FilterHelper.CITYBIKE;

		/// <summary> Gets color of the Citybike button. </summary>
		public Color CitybikeColor => CurrentFilter.GetBikeCategory() == FilterHelper.CITYBIKE ? Color.White : Color.FromRgba(0, 0, 0, 0);
		public Color NoCitybikeColor => CurrentFilter.GetBikeCategory() == FilterHelper.CITYBIKE ? Color.FromRgb(210, 17, 20) : Color.White;

		/// <summary> Gets whether toggle functionality is visible or not. </summary>
		public bool IsToggleVisible =>
			FilterDictionary.Select(x => x.Key).ContainsGroupId(FilterHelper.CITYBIKE)
			&& FilterDictionary.Select(x => x.Key).ContainsGroupId(FilterHelper.CARGOBIKE)
			&& (IsCargoEnabled || IsCitybikeEnabled);

		/// <summary>
		/// Toggles from bike group Cargo to Citybike or vice versa.
		/// Toggling means one of 
		/// - ShareeBike => Citybike or
		/// - ShareeBike => Citybike.
		/// </summary>
		/// <param name="p_strCurrentFilterSet">Filter set to toggle.</param>
		/// <returns></returns>
		public CargoCitybikeToggleViewModel DoToggle()
		{
			var currentFilterSet = FilterDictionary.ToArray();

			if (currentFilterSet.Length < 2)
			{
				// There is nothing to toggle because filter set contains only one element.
				return new CargoCitybikeToggleViewModel(FilterDictionary);
			}

			var currentState = currentFilterSet[currentFilterSet.Length - 1].Value == FilterState.On
				? FilterState.On
				: FilterState.Off;

			var toggledFilterSet = new Dictionary<string, FilterState>();

			foreach (var filterElement in currentFilterSet)
			{
				toggledFilterSet.Add(filterElement.Key, currentState);
				currentState = filterElement.Value;
			}

			return new CargoCitybikeToggleViewModel(new GroupFilterMapPage(toggledFilterSet));
		}
	}
}