using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using System.Windows.Input;

using BeWo.Annotations;
using BeWo.ViewModel;

using BS.Shared.Core;
using BS.Shared.Extensions;


namespace BeWo.View.Controls
{
	public partial class TextModuleTreeViewControl : INotifyPropertyChanged
	{
		public event EventHandler<EventArgs<TextModuleVM>> TextModuleSelected;

		public TextModuleTreeViewControl()
		{
			InitializeComponent();
			DataContext = this;
		}

		public long? ServiceCategoryOid { get; set; }

		private List<TextModuleVM> allTextModules = new List<TextModuleVM>();

		public BindingList<TextModuleVM> FilteredList { get; set; }

		private void OpenPopUpBtnClick(object sender, RoutedEventArgs e)
		{
			VMFactory.CreateTextModuleListVMAsync(
				textModules => this.Dispatch(delegate
				{
					TreeViewPopup.Placement = PlacementMode.RelativePoint;
					TreeViewPopup.HorizontalOffset = 0;
					TreeViewPopup.IsOpen = true;

					allTextModules = textModules.VMList.ToList();

					if(ServiceCategoryOid != null)
					{
						FilteredList = new BindingList<TextModuleVM>();

						var preFilteredTextModules = textModules.VMList.Where(w => w.ServiceCategory != null && w.ServiceCategory.ServiceCategoryOid == ServiceCategoryOid || w.ServiceCategory == null && !w.IsParent).ToList();

						FilteredList.AddRange(preFilteredTextModules);
						SearchTextModulesRecursively(preFilteredTextModules);
					}
					else
					{
						FilteredList = new BindingList<TextModuleVM>(textModules.VMList);
					}
					
					allTextModules = FilteredList.ToList();
					OnPropertyChanged(nameof(FilteredList));
				}));
		}

		private void TreeListControl_OnPreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
		{
			var selectedTextModule = (TextModuleVM) TreeListControl.SelectedItem;

			if(selectedTextModule.IsParent)
			{
				return;
			}

			TreeViewPopup.IsOpen = false;

			TextModuleSelected?.Invoke(this, new EventArgs<TextModuleVM>(selectedTextModule));
		}

		private void SearchTextBox_OnTextChanged(object sender, TextChangedEventArgs e)
		{
			var searchText = ((TextBox) sender).Text.Trim();
			FilteredList.Clear();

			if(searchText.IsNullOrEmpty())
			{
				FilteredList = new BindingList<TextModuleVM>(allTextModules.ToList());
			}
			else
			{
				var matchingChildren = allTextModules.Where(w => w.Name.Contains(searchText) || w.Text != null && w.Text.Contains(searchText)).ToList();

				FilteredList.AddRange(matchingChildren);
				SearchTextModulesRecursively(matchingChildren);
			}

			OnPropertyChanged(nameof(FilteredList));
			TreeListControl.RefreshData();
		}

		private void SearchTextModulesRecursively(IReadOnlyCollection<TextModuleVM> pChildren)
		{
			if(pChildren.Count == 0)
			{
				return;
			}

			foreach(var child in pChildren)
			{
				var parents = allTextModules.Where(w => Equals(child.Parent, w) && !FilteredList.Contains(w)).ToList();

				FilteredList.AddRange(parents);
				SearchTextModulesRecursively(parents);
			}
		}

		public event PropertyChangedEventHandler PropertyChanged;

		[NotifyPropertyChangedInvocator]
		protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
		{
			PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
		}
	}
}