using System.Windows;
using System.Windows.Input;
using Flexitime.Objects;
using FlexitimeTaskbarUtility.Components;
using FlexitimeTaskbarUtility.Events;
using NotifyIconWpf.Sample.Windowless;
using Prism.Events;
using Prism.Ioc;
using Prism.Mvvm;
using Prism.Regions;
using Application = System.Windows.Application;

namespace FlexitimeTaskbarUtility.ViewModels
{
    /// <summary>
    /// Provides bindable properties and commands for the NotifyIcon. In this sample, the
    /// view model is assigned to the NotifyIcon in XAML. Alternatively, the startup routing
    /// in App.xaml.cs could have created this view model, and assigned it to the NotifyIcon.
    /// </summary>
    public class NotifyIconViewModel : BindableBase
    {
        private readonly IEventAggregator _eventAggregator;
        private readonly IRegionManager _regionManager;
        private readonly IContainerProvider _containerProvider;

        public NotifyIconViewModel(IEventAggregator eventAggregator, IRegionManager regionManager, IContainerProvider containerProvider)
        {
            _eventAggregator = eventAggregator;
            _regionManager = regionManager;
            _containerProvider = containerProvider;

            UserStatus = UserState.Unknown;

            _eventAggregator.GetEvent<UserLoggedInEvent>().Subscribe(OnUserLoggedInReceived);
            _eventAggregator.GetEvent<UserLoggedOutEvent>().Subscribe(OnUserLoggedOutReceived);
        }

        /// <summary>
        /// Shows a window, if none is already open.
        /// </summary>
        public ICommand ShowWindowCommand
        {
            get
            {
                return new DelegateCommand
                {
                    CanExecuteFunc = () =>
                        Application.Current.MainWindow == null || Application.Current.MainWindow.Visibility != Visibility.Visible,
                    CommandAction = () =>
                    {
                        Application.Current.MainWindow = new MainWindow();
                        Application.Current.MainWindow.Show();
                    }
                };
            }
        }

        /// <summary>
        /// Hides the main window. This command is only enabled if a window is open.
        /// </summary>
        public ICommand HideWindowCommand
        {
            get
            {
                return new DelegateCommand
                {
                    CommandAction = () =>
                    {
                        Application.Current.MainWindow.Close();
                    },
                    CanExecuteFunc = () => Application.Current.MainWindow != null 
                                           && Application.Current.MainWindow.Visibility == Visibility.Visible
                };
            }
        }

        private UserState _userStatus;

        public UserState UserStatus
        {
            get => _userStatus;
            set => SetProperty(ref _userStatus, value);
        }

        /// <summary>
        /// Shuts down the application.
        /// </summary>
        public ICommand ExitApplicationCommand
        {
            get
            {
                return new DelegateCommand { CommandAction = () => Application.Current.Shutdown() };
            }
        }
        
        public ICommand LoginCommand
        {
            get
            {
                return new DelegateCommand { CommandAction = () => UserStatus = UserState.Out };
            }
        }

        public ICommand SignInCommand
        {
            get
            {
                return new DelegateCommand { CommandAction = () => UserStatus = UserState.Unknown };
            }
        }

        public ICommand TrayContextMenuOpened
        {
            get
            {
                return new DelegateCommand{CommandAction = LoadLoginControl};
            }
        }

        private void OnUserLoggedInReceived(LoginResponse loginResponse)
        {
            UserStatus = UserState.Out;
            IRegion contextMenuRegion = _regionManager.Regions["ContextMenuRegion"];

            var signInView = _containerProvider.Resolve<SigninControl>();
            contextMenuRegion.RemoveAll();
            contextMenuRegion.Add(signInView);
            contextMenuRegion.Activate(signInView);
        }

        private void OnUserLoggedOutReceived()
        {
            UserStatus = UserState.Unknown;
            LoadLoginControl();
        }

        private void LoadLoginControl()
        {
            IRegion contextMenuRegion = _regionManager.Regions["ContextMenuRegion"];

            var loginView = _containerProvider.Resolve<LoginControl>();
            contextMenuRegion.RemoveAll();
            contextMenuRegion.Add(loginView);
            contextMenuRegion.Activate(loginView);
        }
    }
}