using System;
using System.Collections.Generic;
using Avalonia;
using Avalonia.Controls;
using Avalonia.Controls.Primitives;
using Avalonia.Input;
using Avalonia.Interactivity;
using Avalonia.Layout;
using Avalonia.Media;
using Sln.Wcs.UI.ViewModels;

namespace Sln.Wcs.UI.Views;

public partial class MainWindow : Window
{
    private readonly NavigationViewModel _navVm;
    private readonly List<Popup> _openPopups = new();

    public MainWindow(NavigationViewModel navigationVm)
    {
        InitializeComponent();
        _navVm = navigationVm;
        DataContext = _navVm;

        _navVm.PageChanged += OnPageChanged;
        BuildMenu();
        _navVm.LoadDefaultPage();

        // 时钟
        var timer = new System.Timers.Timer(1000);
        timer.Elapsed += (_, _) =>
            Avalonia.Threading.Dispatcher.UIThread.Post(() =>
                ClockText.Text = DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss"));
        timer.Start();
        ClockText.Text = DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss");

        // 退出按钮
        LogoutBtn.Click += (_, _) => Close();
    }

    private void BuildMenu()
    {
        MenuContainer.Children.Clear();
        foreach (var item in _navVm.TopMenuItems)
        {
            var btn = new Button
            {
                Content = item.Label,
                Background = Brushes.Transparent,
                Foreground = Brush.Parse("#8B9BB5"),
                FontSize = 13,
                Padding = new Thickness(14, 12),
                Cursor = new Cursor(StandardCursorType.Hand),
                BorderThickness = new Thickness(0),
            };

            if (item.Action != null)
            {
                btn.Click += (_, _) => item.Action();
            }

            if (item.Children != null && item.Children.Count > 0)
            {
                var popup = new Popup
                {
                    PlacementTarget = btn,
                    Placement = PlacementMode.Bottom,
                    IsLightDismissEnabled = false,
                };

                var popupBorder = new Border
                {
                    Background = Brush.Parse("#0F1620"),
                    BorderBrush = Brush.Parse("#1A2F4A"),
                    BorderThickness = new Thickness(1),
                    CornerRadius = new CornerRadius(4),
                    MinWidth = 160,
                };

                var stack = new StackPanel { Margin = new Thickness(4) };
                foreach (var sub in item.Children)
                {
                    var subBtn = new Button
                    {
                        Content = sub.Label,
                        Background = Brushes.Transparent,
                        Foreground = Brush.Parse("#8B9BB5"),
                        FontSize = 12,
                        HorizontalAlignment = HorizontalAlignment.Stretch,
                        HorizontalContentAlignment = HorizontalAlignment.Left,
                        Padding = new Thickness(12, 8),
                        BorderThickness = new Thickness(0),
                        Cursor = new Cursor(StandardCursorType.Hand),
                    };
                    subBtn.Click += (_, _) =>
                    {
                        popup.Close();
                        sub.Action();
                    };
                    subBtn.PointerEntered += (_, _) =>
                        subBtn.Background = Brush.Parse("#1B3A5C");
                    subBtn.PointerExited += (_, _) =>
                        subBtn.Background = Brushes.Transparent;
                    stack.Children.Add(subBtn);
                }
                popupBorder.Child = stack;
                popup.Child = popupBorder;

                // Hover 展开，离开按钮或 popup 时关闭
                var closeTimer = new System.Timers.Timer(200) { AutoReset = false };
                bool mouseInPopup = false;
                bool mouseInButton = false;

                popupBorder.PointerEntered += (_, _) => { mouseInPopup = true; closeTimer.Stop(); };
                popupBorder.PointerExited += (_, _) => { mouseInPopup = false; TryClose(); };

                btn.PointerEntered += (_, _) =>
                {
                    mouseInButton = true;
                    closeTimer.Stop();
                    btn.Background = Brush.Parse("#1B3A5C");
                    btn.Foreground = Brush.Parse("#4FC3F7");
                    CloseAllPopups();
                    popup.Open();
                };
                btn.PointerExited += (_, _) =>
                {
                    mouseInButton = false;
                    TryClose();
                };

                void TryClose()
                {
                    closeTimer.Stop();
                    closeTimer.Start();
                    closeTimer.Elapsed += (_, _) =>
                    {
                        Avalonia.Threading.Dispatcher.UIThread.Post(() =>
                        {
                            if (!mouseInButton && !mouseInPopup)
                            {
                                popup.Close();
                            }
                        });
                    };
                }

                popup.Closed += (_, _) =>
                {
                    btn.Background = Brushes.Transparent;
                    btn.Foreground = Brush.Parse("#8B9BB5");
                };
                _openPopups.Add(popup);
            }
            else
            {
                btn.PointerEntered += (_, _) =>
                {
                    btn.Background = Brush.Parse("#1B3A5C");
                    btn.Foreground = Brush.Parse("#4FC3F7");
                };
                btn.PointerExited += (_, _) =>
                {
                    btn.Background = Brushes.Transparent;
                    btn.Foreground = Brush.Parse("#8B9BB5");
                };
            }

            MenuContainer.Children.Add(btn);
        }
    }

    private void CloseAllPopups()
    {
        foreach (var p in _openPopups)
            p.Close();
    }

    private void OnPageChanged(Control? view)
    {
        if (view != null)
        {
            view.HorizontalAlignment = HorizontalAlignment.Stretch;
            view.VerticalAlignment = VerticalAlignment.Stretch;
            ContentArea.Child = view;
        }
    }
}