using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using Comal.Classes;
using InABox.Configuration;
using InABox.Core;
using InABox.DynamicGrid;
using InABox.WPF;
using InABox.WPF.Themes;
using Microsoft.Xaml.Behaviors.Core;
using Syncfusion.Windows.Tools.Controls;

namespace PRSDesktop
{
    public class DashboardFavourite : BaseObject
    {
        [TextBoxEditor]
        [EditorSequence(1)]
        public string Name { get; set; }

        [CheckBoxEditor]
        [EditorSequence(2)]
        public bool IsGlobal { get; set; }

        [NullEditor]
        public string Layout { get; set; }
    }

    // public class DynamicItemsListGrid<T> : DynamicGrid<T>
    //     where T : BaseObject, new()
    // {
    //     public List<T> Items { get; set; }
    //
    //     public DynamicItemsListGrid() : this(new()) { }
    //
    //     public DynamicItemsListGrid(List<T> items) : base()
    //     {
    //         Items = items;
    //     }
    //
    //     protected override void DeleteItems(params CoreRow[] rows)
    //     {
    //         foreach (var row in rows.OrderByDescending(x => x.Index))
    //         {
    //             Items.RemoveAt(row.Index);
    //         }
    //     }
    //
    //     protected override T LoadItem(CoreRow row)
    //     {
    //         return Items[row.Index];
    //     }
    //
    //     protected override void Reload(Filters<T> criteria, Columns<T> columns, ref SortOrder<T>? sort, Action<CoreTable?, Exception?> action)
    //     {
    //         var result = new CoreTable();
    //         result.LoadColumns(typeof(T));
    //         result.LoadRows(Items);
    //         action.Invoke(result, null);
    //     }
    //
    //     public override void SaveItem(T item)
    //     {
    //         if (!Items.Contains(item))
    //         {
    //             Items.Add(item);
    //         }
    //     }
    // }

    public class GlobalUtilityDashboardSettings : IGlobalConfigurationSettings
    {
        public List<DashboardFavourite> Favourites { get; set; }

        public GlobalUtilityDashboardSettings()
        {
            Favourites = new();
        }
    }

    public class UtilityDashboardSettings : IUserConfigurationSettings
    {
        public UtilityDashboardSettings()
        {
            Dashboards = new Dictionary<string, string>();
            Favourites = new();
        }

        public Dictionary<string, string> Dashboards { get; set; }

        public List<DashboardFavourite> Favourites { get; set; }

        public int Selected { get; set; }
        public bool AutoHide { get; set; }
    }

    /// <summary>
    ///     Interaction logic for UtilityDashboard.xaml
    /// </summary>
    public partial class UtilityDashboard : UserControl, IBasePanel
    {
        
        private readonly Dictionary<string, DynamicFormDesignGrid> _dashboards = new();

        private readonly Dictionary<DynamicFormDesignGrid, List<ICorePanel>> _panels = new();

        private class WidgetDashboardElement
        {
            public Type DashboardElement { get; set; }

            public Type Widget { get; set; }
            
            public Type Group { get; set; }

            public Type Properties { get; set; }

            public string GroupCaption { get; set; }

            public string WidgetCaption { get; set; }

            public Type[] SecurityTokens { get; set; }

            public WidgetDashboardElement(Type dashboardElement, Type widget, Type group, Type properties, Type[] securityTokens)
            {
                DashboardElement = dashboardElement;
                Widget = widget;
                Group = group;
                Properties = properties;
                SecurityTokens = securityTokens;

                GroupCaption = UtilityDashboard.GetCaption(group);
                WidgetCaption = UtilityDashboard.GetCaption(widget);
            }
        }

        private static List<WidgetDashboardElement>? _dashboardElements;

        private string CurrentDashboardName => ((DashboardsTab.SelectedItem as DynamicTabItem)?.Header?.ToString()) ?? string.Empty;

        private DynamicFormDesignGrid? CurrentDashboard => CurrentDashboardName != null ? _dashboards.GetValueOrDefault(CurrentDashboardName) : null;
        
        private UtilityDashboardSettings _settings = new();

        public UtilityDashboard()
        {
            InitializeComponent();
        }

        public void CreateToolbarButtons(IPanelHost host)
        {
        }

        private void SaveSettings()
        {
            new UserConfiguration<UtilityDashboardSettings>().Save(_settings);
        }

        #region Panel Functions & Properties

        public event DataModelUpdateEvent? OnUpdateDataModel;

        public bool IsReady { get; set; }

        public string SectionName => "Utility Dashboard";

        public DataModel DataModel(Selection selection)
        {
            return new EmptyDataModel();
        }

        public void Setup()
        {
            _settings = new UserConfiguration<UtilityDashboardSettings>().Load();
            if (_settings.Dashboards.Count == 0) _settings.Dashboards["New Dashboard"] = CreateForm("").SaveLayout();

            foreach (var key in _settings.Dashboards.Keys)
                CreateTab(key);

            if (_settings.Selected >= -1 && _settings.Selected < DashboardsTab.Items.Count)
                DashboardsTab.SelectedIndex = _settings.Selected;

            //DashboardsTab.FullScreenMode = _settings.AutoHide ? FullScreenMode.ControlMode : FullScreenMode.None;
        }

        public Dictionary<string, object[]> Selected()
        {
            return new Dictionary<string, object[]>();
        }

        public void Heartbeat(TimeSpan time)
        {
        }

        public void Refresh()
        {
            RefreshDashboard(CurrentDashboardName);
        }

        public void Shutdown()
        {
            foreach (var (name, grid) in _dashboards)
            {
                ShutdownDashboard(name, grid);
            }
            _panels.Clear();
        }

        #endregion

        #region Favourites

        private IEnumerable<DashboardFavourite> GetFavourites()
        {
            foreach(var favourite in _settings.Favourites)
            {
                yield return favourite;
            }
            var global = new GlobalConfiguration<GlobalUtilityDashboardSettings>().Load(false).Favourites;
            foreach (var favourite in global)
            {
                yield return favourite;
            }
        }

        private void ManageFavourites_Click()
        {
            var favourites = GetFavourites().ToList();
            var grid = new DynamicItemsListGrid<DashboardFavourite>() { Items = favourites };
            grid.Options.AddRange(DynamicGridOption.DeleteRows, DynamicGridOption.EditRows, DynamicGridOption.MultiSelect);
            grid.OnCustomiseEditor += FavouritesGrid_OnCustomiseEditor;
            DynamicGridUtils.CreateGridWindow("Manage Favourites", grid).ShowDialog();

            _settings.Favourites = favourites.Where(x => !x.IsGlobal).ToList();
            SaveSettings();

            if (Security.IsAllowed<CanSetGlobalDashboardFavourites>())
            {
                var config = new GlobalConfiguration<GlobalUtilityDashboardSettings>();
                var global = config.Load();
                global.Favourites = favourites.Where(x => x.IsGlobal).ToList();
                config.Save(global);
            }
        }

        private void FavouritesGrid_OnCustomiseEditor(IDynamicEditorForm sender, DashboardFavourite[]? items, DynamicGridColumn column, BaseEditor editor)
        {
            if(column.ColumnName == "IsGlobal")
            {
                editor.Editable = Security.IsAllowed<CanSetGlobalDashboardFavourites>() ? Editable.Enabled : Editable.Disabled;
            }
        }

        private void SaveAsFavourite_Click(string dashboardName)
        {
            _settings.Favourites.Add(new DashboardFavourite
            {
                Name = dashboardName,
                Layout = _dashboards.GetValueOrDefault(dashboardName)?.Form.SaveLayout() ?? _settings.Dashboards[dashboardName]
            });
            SaveSettings();
        }

        private void LoadFavourite_Click(DashboardFavourite favourite)
        {
            var name = CreateNewTabName(favourite.Name);
            _settings.Dashboards[name] = favourite.Layout;
            SaveSettings();

            var tab = CreateTab(name);
            DashboardsTab.SelectedItem = tab;
        }

        #endregion

        #region Tabs

        private void Tab_OnContextMenuOpening(object sender, DynamicTabItemContextMenuEventArgs args)
        {
            var name = (DashboardsTab.SelectedItem as DynamicTabItem)?.Header?.ToString();
            if (string.IsNullOrEmpty(name))
                return;

            DynamicFormDesignGrid grid = _dashboards[name];

            var menu = args.Menu;
            menu.AddSeparatorIfNeeded();

            var isDesigning = grid.Mode != FormMode.Preview;
            menu.Items.Add(new MenuItem()
            {
                Header = isDesigning ? "Close Design Mode" : "Design Mode",
                Command = new ActionCommand(() =>
                {
                    if (grid.Mode == FormMode.Designing)
                    {
                        grid.Mode = FormMode.Preview;
                        SaveCurrentDashboard();
                        DashboardsTab.ChangedCommand.Execute(null);
                    }
                    else
                    {
                        ShutdownDashboard();
                        grid.Mode = FormMode.Designing;
                    }
                }),
                Icon = new Image() { Source = (isDesigning ? PRSDesktop.Resources.delete : PRSDesktop.Resources.pencil).AsBitmapImage(24, 24) }
            });

            var index = 0;
            var favourites = GetFavourites().ToList();
            if (favourites.Any())
            {
                foreach (var favourite in favourites)
                {
                    menu.AddItem(favourite.Name, null, favourite, LoadFavourite_Click, index: index++);
                }
                menu.AddSeparatorIfNeeded(index: index++);
                menu.AddItem("Manage Favourites", null, ManageFavourites_Click, index: index++);
            }
            menu.AddItem("Save as Favourite", null, name, SaveAsFavourite_Click, index: index++);

            menu.AddSeparator(index: index++);
        }

        private void Tab_OnCloseTab(object sender, DynamicTabControlEventArgs args)
        {
            var name = args.TabItem.Header?.ToString();
            if (name is null)
                return;
            _dashboards.Remove(name);
            _settings.Dashboards.Remove(name);

            if (!_settings.Dashboards.Any())
            {
                var tab = new DynamicTabItem();
                InitializeNewDashboardTab(tab);
                DashboardsTab.Items.Add(tab);
            }
            else
            {
                DashboardsTab.ChangedCommand.Execute(null);
            }
        }

        private void Tab_OnTabRenamed(object sender, DynamicTabItemRenamedEventArgs args)
        {
            var oldSettings = _settings.Dashboards[args.OldName];
            _settings.Dashboards.Remove(args.OldName);

            args.NewName = CreateNewTabName(args.NewName);

            if (_dashboards.TryGetValue(args.OldName, out var dashboard))
            {
                _dashboards.Remove(args.OldName);
                _dashboards[args.NewName] = dashboard;
                _settings.Dashboards[args.NewName] = dashboard.Form.SaveLayout();
            }
            else
            {
                _settings.Dashboards[args.NewName] = oldSettings;
            }
        }

        /// <summary>
        /// Setup events on a new tab.
        /// </summary>
        /// <param name="tab"></param>
        private void InitializeTab(DynamicTabItem tab)
        {
            tab.CanClose = true;
            tab.OnCloseTab += Tab_OnCloseTab;
            tab.CanRename = true;
            tab.OnTabRenamed += Tab_OnTabRenamed;
            tab.OnContextMenuOpening += Tab_OnContextMenuOpening;
        }

        private string CreateNewTabName(string name)
        {
            var newName = name;
            int i = 1;
            while (TabNameExists(newName))
            {
                newName = $"{name} ({i})";
                ++i;
            }
            return newName;
        }

        private bool TabNameExists(string name)
        {
            return _settings.Dashboards.ContainsKey(name);
        }

        /// <summary>
        /// Creates a new tab with a given header and adds it to <see cref="DashboardsTab"/>.
        /// </summary>
        /// <param name="header"></param>
        /// <returns></returns>
        private DynamicTabItem CreateTab(string header)
        {
            var tab = new DynamicTabItem() { Header = header };
            InitializeTab(tab);
            DashboardsTab.Items.Add(tab);
            return tab;
        }

        /// <summary>
        /// Creates a new dashboard for a tab, and then initializes the tab.
        /// </summary>
        /// <param name="tab"></param>
        private void InitializeNewDashboardTab(DynamicTabItem tab)
        {
            var name = CreateNewTabName("New Dashboard");

            _settings.Dashboards[name] = CreateForm("").SaveLayout();
            DashboardsTab.ChangedCommand.Execute(null);

            SaveSettings();

            tab.Header = name;
            InitializeTab(tab);
        }

        private void DashboardsTab_OnOnCreateTab(object sender, DynamicTabControlEventArgs args)
        {
            InitializeNewDashboardTab(args.TabItem);
        }

        private void DashboardsTab_OnSelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            if (e.OriginalSource != DashboardsTab)
                return;

            if (e.AddedItems.Count == 0)
                return;

            ShutdownDashboard();
            if (e.AddedItems[0] is DynamicTabItem tab)
            {
                var name = (tab.Header as string)!;
                if (tab!.Content == null)
                    tab.Content = CreateDashboard(name, _settings.Dashboards[name]);
                else
                {
                    RefreshDashboard(name);
                }

                if (IsReady)
                {
                    _settings.Selected = tab.TabIndex;
                    DashboardsTab.ChangedCommand.Execute(null);
                }
            }
        }

        private void DashboardsTab_OnOnTabsChanged(object sender, EventArgs args)
        {
            SaveSettings();
        }

        #endregion

        #region Dashboard & Design

        private void SaveDashboard(string name, DynamicFormDesignGrid grid)
        {
            _settings.Dashboards[name] = grid.Form.SaveLayout();
            if (IsReady)
                SaveSettings();
        }

        private void SaveCurrentDashboard()
        {
            var name = CurrentDashboardName;
            if (name == null) return;
            var grid = CurrentDashboard;
            if (grid == null) return;
            SaveDashboard(name, grid);
        }

        private void ShutdownDashboard(string name, DynamicFormDesignGrid grid)
        {
            SaveDashboard(name, grid);
            foreach (var panel in _panels[grid])
            {
                panel.Shutdown();
            }
            _panels[grid].Clear();
        }

        private void ShutdownDashboard()
        {
            var name = CurrentDashboardName;
            if (name == null) return;
            var grid = CurrentDashboard;
            if (grid == null) return;
            ShutdownDashboard(name, grid);
        }

        private void RefreshDashboard(string name)
        {
            if (!_dashboards.ContainsKey(name))
                return;
            var grid = _dashboards[name];
            if (_panels.ContainsKey(grid))
            {
                foreach (var panel in _panels[grid])
                    panel.Refresh();
            }
        }

        private FrameworkElement CreateElement<TWidget, TGroup, TProperties>(DynamicFormDesignGrid grid, DFLayoutElement<TProperties> element)
            where TWidget : FrameworkElement, IDashboardWidget<TGroup, TProperties>, new()
            where TGroup : DashboardWidgetGroup
            where TProperties : IConfigurationSettings, IDashboardProperties, new()
        {
            if (!_panels.ContainsKey(grid))
                _panels[grid] = new List<ICorePanel>();

            var dashboardName = GetDashboardElements()
                .Where(x => x.DashboardElement == element.GetType())
                .FirstOrDefault()?.WidgetCaption ?? "Unknown Dashboard";

            var container = DashboardContainer.Create<TWidget, TGroup, TProperties>(element, dashboardName);

            _panels[grid].Add(container.Panel);

            return container;
        }

        private FrameworkElement OnCreateElement(object sender, DynamicFormCreateElementArgs e)
        {
            var widgetType = GetVisibleDashboardElements().Where(x => x.DashboardElement == e.Element.GetType()).FirstOrDefault();
            if(widgetType == null)
            {
                var border = new Border
                {
                    BorderBrush = new SolidColorBrush(Colors.Gray),
                    BorderThickness = new Thickness(0.0),
                    Margin = new Thickness(0.0),
                    Background = ThemeManager.WorkspaceBackgroundBrush //new SolidColorBrush(Colors.Silver);
                };
                return border;
            }
            var method = typeof(UtilityDashboard)
                .GetMethod(nameof(CreateElement), BindingFlags.Instance | BindingFlags.NonPublic)!
                .MakeGenericMethod(widgetType.Widget, widgetType.Group, widgetType.Properties);
            return (method.Invoke(this, new object[] { sender, e.Element }) as FrameworkElement)!;
        }
        
        private static string GetCaption(Type groupType)
        {
            var caption = groupType.GetCustomAttribute<Caption>();
            if(caption != null)
            {
                return caption.Text;
            }
            return CoreUtils.Neatify(groupType.Name);
        }

        private static List<WidgetDashboardElement> GetDashboardElements()
        {
            if (_dashboardElements == null)
            {
                _dashboardElements = new();
                var types = CoreUtils.TypeList(
                    AppDomain.CurrentDomain.GetAssemblies(),
                    x => x.IsClass
                        && !x.IsAbstract
                        && !x.IsGenericType);
                foreach (var type in types)
                {
                    var dashboardElementDef = type.GetSuperclassDefinition(typeof(DashboardElement<,,>));

                    if (dashboardElementDef != null)
                    {

                        var dashboard = dashboardElementDef.GenericTypeArguments[0];
                        var group = dashboardElementDef.GenericTypeArguments[1];
                        var properties = dashboardElementDef.GenericTypeArguments[2];

                        var requires = dashboard.GetInterfaces(typeof(IRequiresSecurity<>)).Select(x => x.GenericTypeArguments[0]);
                        _dashboardElements.Add(new(type, dashboard, group, properties, requires.ToArray()));
                    }
                }
            }
            return _dashboardElements;
        }

        private static IEnumerable<WidgetDashboardElement> GetVisibleDashboardElements()
        {
            return GetDashboardElements().Where(x =>
            {
                foreach (var require in x.SecurityTokens)
                {
                    if (!Security.IsAllowed(require))
                        return false;
                }
                return true;
            });
        }

        private Border CreateDashboard(string name, string layout)
        {
            var form = CreateForm(layout);

            var grid = new DynamicFormDesignGrid();

            foreach(var widget in GetVisibleDashboardElements())
            {
                grid.AddElement(widget.DashboardElement, widget.WidgetCaption, widget.GroupCaption, true);
            }

            grid.ShowBorders = false;
            grid.OnCreateElement += OnCreateElement;
            grid.OnAfterDesign += OnAfterDesign;
            grid.OnAfterRender += OnAfterRender;

            grid.Mode = FormMode.Preview;

            var border = new Border
            {
                BorderBrush = new SolidColorBrush(Colors.Silver),
                BorderThickness = new Thickness(0.75),
                Child = grid // scroll;
            };

            _dashboards[name] = grid;
            _panels[grid] = new List<ICorePanel>();

            grid.Form = form;

            grid.Initialize();

            return border;
        }

        private void OnAfterRender(DynamicFormDesignGrid sender)
        {
            if (!sender.IsDesigning)
            {
                if (_panels.TryGetValue(sender, out var panels))
                {
                    foreach (var panel in panels)
                        panel.Refresh();
                }
            }
        }

        private static DFLayout CreateForm(string layout)
        {
            var form = new DFLayout();
            if (string.IsNullOrWhiteSpace(layout))
            {
                form.ColumnWidths.Add("*");
                form.ColumnWidths.Add("*");
                form.ColumnWidths.Add("*");
                form.RowHeights.Add("*");
                form.RowHeights.Add("*");
                form.RowHeights.Add("*");
            }
            else
            {
                form.LoadLayout(layout);
            }

            return form;
        }
        
        private void OnAfterDesign(object sender)
        {
            SaveCurrentDashboard();
            RefreshDashboard(CurrentDashboardName);
        }

        #endregion
    }
}