using System;
using System.Collections.Generic;
using Avalonia.Controls;
using Avalonia.Markup.Xaml;
using CRD.Utils.Updater;
using CRD.ViewModels;
using CRD.Views.Utils;
using FluentAvalonia.Core;
using FluentAvalonia.UI.Controls;
using FluentAvalonia.UI.Windowing;
using ReactiveUI;

namespace CRD.Views;

public partial class MainWindow : AppWindow{
    private Stack<object> navigationStack = new Stack<object>();


    #region Singelton

    private static MainWindow? _instance;
    private static readonly object Padlock = new();

    public static MainWindow Instance{
        get{
            if (_instance == null){
                lock (Padlock){
                    if (_instance == null){
                        _instance = new MainWindow();
                    }
                }
            }

            return _instance;
        }
    }

    #endregion


    private object selectedNavVieItem;

    public MainWindow(){
        AvaloniaXamlLoader.Load(this);
        InitializeComponent();

        TitleBar.ExtendsContentIntoTitleBar = true;
        TitleBar.TitleBarHitTestType = TitleBarHitTestType.Complex;


        //select first element as default
        var nv = this.FindControl<NavigationView>("NavView");
        nv.SelectedItem = nv.MenuItems.ElementAt(0);
        selectedNavVieItem = nv.SelectedItem;

        MessageBus.Current.Listen<NavigationMessage>()
            .Subscribe(message => {
                if (message.Refresh){
                    navigationStack.Pop();
                    var viewModel = Activator.CreateInstance(message.ViewModelType);
                    navigationStack.Push(viewModel);
                    nv.Content = viewModel;
                } else if (!message.Back && message.ViewModelType != null){
                    var viewModel = Activator.CreateInstance(message.ViewModelType);
                    navigationStack.Push(viewModel);
                    nv.Content = viewModel;
                } else{
                    navigationStack.Pop();
                    var viewModel = navigationStack.Peek();
                    nv.Content = viewModel;
                }
            });

        MessageBus.Current.Listen<ToastMessage>()
            .Subscribe(message => ShowToast(message.Message, message.Type, message.Seconds));
    }

    public async void ShowError(string message){
        var dialog = new ContentDialog(){
            Title = "Error",
            Content = message,
            CloseButtonText = "Close"
        };

        _ = await dialog.ShowAsync();
    }


    public void ShowToast(string message, ToastType type, int durationInSeconds = 5){
        this.FindControl<ToastNotification>("Toast").Show(message, type, durationInSeconds);
    }


    private void NavView_SelectionChanged(object? sender, NavigationViewSelectionChangedEventArgs e){
        if (sender is NavigationView navView){
            var selectedItem = navView.SelectedItem as NavigationViewItem;
            if (selectedItem != null){
                switch (selectedItem.Tag){
                    case "DownloadQueue":
                        navView.Content = Activator.CreateInstance(typeof(DownloadsPageViewModel));
                        selectedNavVieItem = selectedItem;
                        break;
                    case "AddDownload":
                        navView.Content = Activator.CreateInstance(typeof(AddDownloadPageViewModel));
                        selectedNavVieItem = selectedItem;
                        break;
                    case "Calendar":
                        navView.Content = Activator.CreateInstance(typeof(CalendarPageViewModel));
                        selectedNavVieItem = selectedItem;
                        break;
                    case "History":
                        navView.Content = Activator.CreateInstance(typeof(HistoryPageViewModel));
                        navigationStack.Clear();
                        navigationStack.Push(navView.Content);
                        selectedNavVieItem = selectedItem;
                        break;
                    case "Account":
                        navView.Content = Activator.CreateInstance(typeof(AccountPageViewModel));
                        selectedNavVieItem = selectedItem;
                        break;
                    case "Settings":
                        navView.Content = Activator.CreateInstance(typeof(SettingsPageViewModel));
                        selectedNavVieItem = selectedItem;
                        break;
                    case "UpdateAvailable":
                        Updater.Instance.DownloadAndUpdateAsync();
                        ShowUpdateDialog();
                        break;
                    default:
                        // (sender as NavigationView).Content = Activator.CreateInstance(typeof(DownloadsPageViewModel));
                        break;
                }
            }
        }
    }

    public async void ShowUpdateDialog(){
        var dialog = new ContentDialog(){
            Title = "Updating",
            // CloseButtonText = "Close"
        };

        var viewModel = new ContentDialogUpdateViewModel(dialog);
        dialog.Content = new ContentDialogUpdateView(){
            DataContext = viewModel
        };

        _ = await dialog.ShowAsync();
    }
}

public class ToastMessage(string message, ToastType type, int i){
    public string? Message{ get; set; } = message;
    public int Seconds{ get; set; } = i;
    public ToastType Type{ get; set; } = type;
}

public class NavigationMessage{
    public Type? ViewModelType{ get; }
    public bool Back{ get; }
    public bool Refresh{ get; }

    public NavigationMessage(Type? viewModelType, bool back, bool refresh){
        ViewModelType = viewModelType;
        Back = back;
        Refresh = refresh;
    }
}