using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using Serilog;
using TINK.Model.Connector;
using TINK.Model.MiniSurvey;
using TINK.MultilingualResources;
using TINK.Repository.Exception;
using TINK.View;
using TINK.ViewModel.MiniSurvey.Question;

namespace TINK.ViewModel.MiniSurvey
{
	public class MiniSurveyViewModel : ObservableCollection<IMiniSurveyQuestion>
	{
		/// <summary> Delegate to retrieve connected state. </summary>
		protected Func<bool> IsConnectedDelegate { get; }

		/// <summary> Provides a connector object.</summary>
		private Func<bool, IConnector> ConnectorFactory { get; }

		/// <summary>
		/// Reference on view service to show modal notifications and to perform navigation.
		/// </summary>
		private IViewService ViewService { get; }

		private MiniSurveyModel MiniSurvey { get; }

		/// <summary> Constructs mini survey view model.</summary>
		/// <param name="connectorFactory">Connects system to copri for purposes of requesting a bike/ cancel request.</param>
		/// <param name="viewService">Interface to actuate methodes on GUI.</param>
		public MiniSurveyViewModel(
			Func<bool> isConnectedDelegate,
			Func<bool, IConnector> connectorFactory,
			IViewService viewService)
		{
			IsConnectedDelegate = isConnectedDelegate
				?? throw new ArgumentException($"Can not instantiate {nameof(MiniSurveyViewModel)}-object. No connector available.");

			ConnectorFactory = connectorFactory
				?? throw new ArgumentException($"Can not instantiate {nameof(MiniSurveyViewModel)}-object. No connector available.");

			ViewService = viewService
				?? throw new ArgumentException($"Can not instantiate {nameof(MiniSurveyViewModel)}-object. No view available.");

			MiniSurvey = new MiniSurveyModel
			{
				Title = "Bitte unterstützen Sie unsere Begleitforschung",
				Subtitle = "Ihre drei Antworten werden anonym gespeichert.",
				Footer = "Herzlichen Dank und viel Spaß bei der nächsten Fahrt!"
			};

			MiniSurvey.Questions.Add(
				"q1",
				new QuestionModel
				{
					Text = "1. Was war der Hauptzweck dieser Ausleihe?",
					Type = MiniSurveyModel.Type.SingleAnswer
				});

			MiniSurvey.Questions.Add(
				"q2",
				new QuestionModel
				{
					Text = "2. Welches Verkehrsmittel hätten Sie ansonsten benutzt?",
					Type = MiniSurveyModel.Type.SingleAnswer
				});

			MiniSurvey.Questions.Add(
				"q3",
				new QuestionModel
				{
					Text = "3. Haben Sie Anmerkungen oder Anregungen?",
					Type = MiniSurveyModel.Type.CustomText
				});

			MiniSurvey.Questions["q1"].PossibleAnswers.Add("opt1", "a. Einkauf");
			MiniSurvey.Questions["q1"].PossibleAnswers.Add("opt2", "b. Kinderbeförderung");
			MiniSurvey.Questions["q1"].PossibleAnswers.Add("opt3", "c. Lastentransport");
			MiniSurvey.Questions["q1"].PossibleAnswers.Add("opt4", "d. Freizeit");
			MiniSurvey.Questions["q1"].PossibleAnswers.Add("opt5", "e. Ausprobieren");
			MiniSurvey.Questions["q1"].PossibleAnswers.Add("opt6", "f. Sonstiges");

			MiniSurvey.Questions["q2"].PossibleAnswers.Add("opt1", "a. Auto");
			MiniSurvey.Questions["q2"].PossibleAnswers.Add("opt2", "b. Motorrad oder Motorroller");
			MiniSurvey.Questions["q2"].PossibleAnswers.Add("opt3", "c. Bus oder Bahn");
			MiniSurvey.Questions["q2"].PossibleAnswers.Add("opt4", "d. Eigenes Fahrrad");
			MiniSurvey.Questions["q2"].PossibleAnswers.Add("opt5", "e. Zu Fuß");
			MiniSurvey.Questions["q2"].PossibleAnswers.Add("opt6", "f. Keines (ich hätte die Fahrt sonst nicht gemacht)");

			Title = MiniSurvey.Title;
			Subtitle = MiniSurvey.Subtitle;
			Footer = MiniSurvey.Footer;

			foreach (var question in MiniSurvey.Questions)
			{
				switch (question.Value.Type)
				{
					case MiniSurveyModel.Type.SingleAnswer:
						Add(new CheckOneViewModel(
							new KeyValuePair<string, string>(question.Key, question.Value.Text),
							question.Value.PossibleAnswers));
						break;

					case MiniSurveyModel.Type.CustomText:
						Add(new FreeTextViewModel(new KeyValuePair<string, string>(question.Key, question.Value.Text)));
						break;

					default:
						break;
				}
			}
		}

		public string Title { get; set; }

		public string Subtitle { get; set; }

		public string Footer { get; set; }

		/// <summary> Processes request to perform a copri action (reserve bike and cancel reservation). </summary>
		public System.Windows.Input.ICommand OnButtonClicked => new Xamarin.Forms.Command(async () =>
		{
			Log.ForContext<MiniSurveyViewModel>().Information($"User result {this[0].Answer.Value}, {this[1].Answer.Value}");

			var isConnected = IsConnectedDelegate();
			try
			{
				await ConnectorFactory(isConnected).Command.DoSubmitMiniSurvey(this.ToDictionary(x => x.Question.Key, x => x.Answer.Key));
			}
			catch (Exception exception)
			{
				if (exception is ResponseException copriException)
				{
					// Copri server is not reachable.
					Log.ForContext<MiniSurveyViewModel>().Information("Submitting mini survay answer failed. COPRI returned an error.");
				}
				else
				{
					Log.ForContext<MiniSurveyViewModel>().Error("Submitting mini survay answer failed. {@l_oException}", exception);
				}

				await ViewService.DisplayAlert(
					AppResources.ErrorReturnSubmitFeedbackTitle,
					AppResources.ErrorReturnSubmitFeedbackMessage,
					AppResources.MessageAnswerOk);
			}

			await ViewService.PopModalAsync();
		});
	}
}