using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Input;

using BeWo.ServiceProxy;
using BeWo.ViewModel;
using BeWo.ViewModel.ListViewModel;

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

using DevExpress.Xpf.Editors;
using DevExpress.Xpf.Grid;

namespace BeWo.View.Detail
{
    public partial class TextbausteinView
    {
        private TextModuleListVM _ViewModel;

        public TextModuleListVM ViewModel
        {
            get => _ViewModel;

            set
            {
                _ViewModel = value;
                root.DataContext = value;
            }
        }

        public override bool IsDirty => ViewModel != null && ViewModel.IsDirty;

        private readonly bool _IsInAdministrationView;

        public TextbausteinView(TextModuleListVM pViewModel, bool pIsInAdministrationView = false)
        {
            InitializeComponent();

            _IsInAdministrationView = pIsInAdministrationView;

            ViewModel = pViewModel;
        }

        protected override void Save()
        {
            Save(null);
        }

        public void Save(Action pCallBack)
        {
            var lToDos = new List<Action<IOperationsService>>();
            
            if(ViewModel.ChangedCount == 0 && ViewModel.RemovedCount == 0 && ViewModel.AddedCount == 0)
            {
                return;
            }

            if (ViewModel.AddedCount > 0)
            {
                lToDos.Add(s => s.InsertNewTextModules(ViewModel.CommitAdded()));
            }

            if (ViewModel.RemovedCount > 0)
            {
                lToDos.Add(s => s.DeleteTextModules(ViewModel.GetRemoved().ToDictionary(dc => dc.TextModuleOid.Value, dc => dc.TextModuleVersion.Value)));
            }

            if (ViewModel.ChangedCount > 0)
            {
                lToDos.Add(s => s.UpdateTextModules(ViewModel.CommitChanged()));
            }

            ServiceFacade.DoMultipleOperationsServicesAsync(lToDos, () =>
            {
                pCallBack?.Invoke();
                ReloadViewModel();
            });
        }

        private void ReloadViewModel()
        {
            VMFactory.CreateTextModuleListVMAsync(r => this.Dispatch(delegate
            {
                TreeListControl.BeginDataUpdate();

                ViewModel = r;

                TreeListControl.EndDataUpdate();

                TreeListControl.SelectedItems.Clear();

            }), _IsInAdministrationView);
        }

        private void DeleteButton_Click(object sender, RoutedEventArgs e)
        {
            var focusedNode = TreeListView.FocusedNode;
            var selectedTextModule = (TextModuleVM) focusedNode.Content;

            _ChildrenToDelete.Add(selectedTextModule);

            if(selectedTextModule.IsParent)
            {
                if(ViewModel.VMList.Any(textModule => selectedTextModule.Equals(textModule.Parent)))
                {
                    if(MessageBox.Show("Die Textbausteinkategorie enthält weitere Textbausteine und/oder Textbausteinkategorien. Wenn Sie fortfahren, werden alle Unterelemente von \"" + selectedTextModule.Name + "\" gelöscht.", "Textbausteine löschen", MessageBoxButton.OKCancel, MessageBoxImage.Question) == MessageBoxResult.Cancel)
                    {
                        _ChildrenToDelete.Clear();
                        return;
                    }
                }

                RetrieveChildTextModulesFromParent(selectedTextModule);
            }

            ViewModel.VMList.RemoveRange(_ChildrenToDelete);
            _ChildrenToDelete.Clear();
        }

        private readonly List<TextModuleVM> _ChildrenToDelete = new List<TextModuleVM>();
        
        private void RetrieveChildTextModulesFromParent(TextModuleVM parent)
        {
            var children = ViewModel.VMList.Where(w => w.Parent != null && w.Parent.Equals(parent));

            foreach(var child in children)
            {
                _ChildrenToDelete.Add(child);
                RetrieveChildTextModulesFromParent(child);
            }
        }

        public static bool CheckEditorRights(TextModuleVM textbausteinVM, object parameter)
        {
            if (textbausteinVM != null)
            {
                var isOwn = textbausteinVM.Employee != null && textbausteinVM.Employee.EmployeeOid.Equals(BeWoApp.LoggedOnEmployee.EmployeeOid);

                var hasRight2EditAll = BeWoApp.LoggedOnUser.HasRight(UserRightType.TextbausteineAlleBearbeiten);
                var hasRight2EditOwn = BeWoApp.LoggedOnUser.HasRight(UserRightType.TextbausteineNurEigeneBearbeiten);
                var hasRight2Create4All = BeWoApp.LoggedOnUser.HasRight(UserRightType.TextbausteineAlleBearbeiten);

                if (parameter != null && parameter.ToString().Equals("IsOnlyForEmployeeCheckBox"))
                {
                    return isOwn && hasRight2EditOwn && hasRight2Create4All || hasRight2EditAll;
                }

                return isOwn && hasRight2EditOwn || hasRight2EditAll;
            }

            return false;
        }

        private void ContextMenuTextModules_Click(object sender, RoutedEventArgs e)
        {
            if(e.OriginalSource is MenuItem twi)
            {
                var selectedItem = TreeListControl.SelectedItem as TextModuleVM;

                ViewModel.NewVM.IsParent = twi.Header.Equals("Neue Textbausteinkategorie");
                ViewModel.NewVM.IsExpanded = twi.Header.Equals("Neue Textbausteinkategorie");
                ViewModel.NewVM.IsOnlyForEmployee = !_IsInAdministrationView;
                ViewModel.NewVM.Name = GenerateNewTextModuleName(twi.Header.ToString());

                if(selectedItem != null)
                {
                    ViewModel.NewVM.Parent = selectedItem;
                }

                ViewModel.AddNewVMToList(false);
                Save();
            }
        }

        private string GenerateNewTextModuleName(string pName)
        {
            var newName = pName;
            var counter = 1;

            while(ViewModel.VMList.Any(a => a.Name.Equals(newName)))
            {
                newName = pName + " " + counter;
                counter++;
            }

            return newName;
        }

        private void ContextMenuTextModules_Opened(object sender, RoutedEventArgs e)
        {
            if (e.OriginalSource is ContextMenu menu)
            {
                var textModule = TreeListControl.SelectedItem as TextModuleVM;

                foreach (var menuitem in menu.Items.OfType<MenuItem>().Select(item => item))
                {
                    if(textModule != null && !textModule.IsParent)
                    {
                        menuitem.IsEnabled = false;
                    }
                    else
                    {
                        menuitem.IsEnabled = true;
                    }
                }
            }
        }

        private void TreeListControl_OnItemsSourceChanged(object sender, ItemsSourceChangedEventArgs e)
        {
            TreeListControl.SelectedItem = null;
        }

        private void TreeListControl_OnPreviewMouseDown(object sender, MouseButtonEventArgs e)
        {
            var hitInfo = TreeListView.CalcHitInfo(e.OriginalSource as DependencyObject);
            if(!hitInfo.InRowCell)
            {
                TreeListControl.SelectedItem = null;
            }

            e.Handled = false;
        }

        private void ButtonInfo_OnClick(object sender, RoutedEventArgs e)
        {
            if(sender is Button btn && btn.TemplatedParent is ButtonContainer bc)
            {
                if(bc.Content is ButtonInfo bi)
                {
                    if(bi.Tag is EditGridCellData cellData)
                    {
                        var vm = (TextModuleVM) cellData.RowData.Row;

                        vm.Parent = null;
                        vm.IsParent = false;
                    }
                }
            }
        }

        private void RemoveServiceCategory_OnClick(object sender, RoutedEventArgs e)
        {
            if(sender is Button btn && btn.TemplatedParent is ButtonContainer bc)
            {
                if(bc.Content is ButtonInfo bi)
                {
                    if(bi.Tag is EditGridCellData cellData)
                    {
                        var vm = (TextModuleVM) cellData.RowData.Row;

                        vm.ServiceCategory = null;
                    }
                }
            }
        }

        // TODO: wird das gebraucht? Was tut es?
        private void PART_Editor_OnEditValueChanged(object sender, EditValueChangedEventArgs e)
        {
            var comboBoxEdit = (ComboBoxEdit) sender;
            var selectedTextModule = (TextModuleVM) comboBoxEdit.Tag;

            var oldValue = e.OldValue;
            var newValue = e.NewValue;

            if(e.NewValue != null)
            {
                selectedTextModule.Parent = (TextModuleVM) e.NewValue;
            }
        }

        private void FrameworkElement_OnLoaded(object sender, RoutedEventArgs e)
        {
            var comboBoxEdit = (ComboBoxEdit) sender;

            var textModule = (TextModuleVM) comboBoxEdit.Tag;

            comboBoxEdit.ItemsSource = ViewModel.GetTextModuleParents(textModule);
        }

        private void RemoveServiceCategoryFromNewVM_OnClick(object sender, RoutedEventArgs e)
        {
            ViewModel.NewVM.ServiceCategory = null;
        }

        private void RemoveParentTextModuleFromNewVM_OnClick(object sender, RoutedEventArgs e)
        {
            ViewModel.NewVM.Parent = null;
        }

        private void IsTextModuleParent_Checked(object sender, RoutedEventArgs e)
        {
            ViewModel.NewVM.Text = null;
        }

        private void AddTextModuleButton_Click(object sender, RoutedEventArgs e)
        {
            ViewModel.NewVM.IsOnlyForEmployee = !_IsInAdministrationView;
            ViewModel.AddNewVMToList(false);
            Save();
        }
    }

    public class IsOnlyForEmployeeRightsConverter : IValueConverter
    {
        public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
        {
            var textbausteinVM = (TextModuleVM)value;

            return TextbausteinView.CheckEditorRights(textbausteinVM, parameter) && textbausteinVM != null && !textbausteinVM.IsParent;
        }

        public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }
}