using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using Avalonia.Controls;
using CommunityToolkit.Mvvm.ComponentModel;
using Microsoft.Extensions.DependencyInjection;
using Sln.Wcs.UI.ViewModels.Base;
using Sln.Wcs.UI.ViewModels.Device;
using Sln.Wcs.UI.ViewModels.Path;
using Sln.Wcs.UI.ViewModels.Task;
using Sln.Wcs.UI.Views;

namespace Sln.Wcs.UI.ViewModels;

public partial class NavigationViewModel : ObservableObject
{
    private readonly IServiceProvider _sp;
    private readonly Dictionary<Type, ICrudPageViewModel> _vmCache = new();
    private readonly Dictionary<Type, Control> _viewCache = new();
    private Control? _homeView;

    public ObservableCollection<TopMenuItem> TopMenuItems { get; } = new();

    public event Action<Control?>? PageChanged;

    public NavigationViewModel(IServiceProvider sp)
    {
        _sp = sp;
        BuildMenu();
    }

    public void LoadDefaultPage() => ShowHome();

    private void BuildMenu()
    {
        TopMenuItems.Clear();
        TopMenuItems.Add(new TopMenuItem("首页", ShowHome));
        TopMenuItems.Add(new TopMenuItem("基础数据", new List<SubMenuItem>
        {
            new("库位信息", () => NavigateTo<LocationInfoViewModel>()),
            new("物料信息", () => NavigateTo<MaterialInfoViewModel>()),
            new("仓库信息", () => NavigateTo<StoreInfoViewModel>()),
        }));
        TopMenuItems.Add(new TopMenuItem("设备管理", new List<SubMenuItem>
        {
            new("设备主机", () => NavigateTo<DeviceHostViewModel>()),
            new("设备信息", () => NavigateTo<DeviceInfoViewModel>()),
            new("设备参数", () => NavigateTo<DeviceParamViewModel>()),
        }));
        TopMenuItems.Add(new TopMenuItem("路径管理", new List<SubMenuItem>
        {
            new("路径信息", () => NavigateTo<PathInfoViewModel>()),
            new("路径明细", () => NavigateTo<PathDetailsViewModel>()),
        }));
        TopMenuItems.Add(new TopMenuItem("任务管理", new List<SubMenuItem>
        {
            new("任务队列", () => NavigateTo<TaskQueueViewModel>()),
            new("任务明细", () => NavigateTo<TaskDetailViewModel>()),
        }));
    }

    private void ShowHome()
    {
        if (_homeView == null)
        {
            var vm = _sp.GetRequiredService<HomePageViewModel>();
            _homeView = new HomePageView { DataContext = vm };
        }
        PageChanged?.Invoke(_homeView);
    }

    private void NavigateTo<T>() where T : ICrudPageViewModel
    {
        var type = typeof(T);
        if (!_vmCache.TryGetValue(type, out var vm))
        {
            vm = _sp.GetRequiredService<T>();
            _vmCache[type] = vm;
        }
        if (!_viewCache.TryGetValue(type, out var view))
        {
            view = vm.CreateView();
            view.DataContext = vm;
            _viewCache[type] = view;
        }
        PageChanged?.Invoke(view);
        vm.Load();
    }
}

public class TopMenuItem
{
    public string Label { get; set; }
    public List<SubMenuItem>? Children { get; set; }
    public Action? Action { get; set; }

    public TopMenuItem(string label, Action action)
    {
        Label = label; Action = action;
    }

    public TopMenuItem(string label, List<SubMenuItem> children)
    {
        Label = label; Children = children;
    }
}

public class SubMenuItem
{
    public string Label { get; set; }
    public Action Action { get; set; }

    public SubMenuItem(string label, Action action)
    {
        Label = label; Action = action;
    }
}