using System;
using System.Collections.Generic;
using System.Linq;
using Comal.Classes;
using InABox.Core;
using InABox.Mobile;
using Xamarin.Forms;
using Xamarin.Forms.Xaml;
using XF.Material.Forms.UI.Dialogs;

namespace PRS.Mobile
{
    
    [XamlCompilation(XamlCompilationOptions.Compile)]
    public partial class KanbanList 
    {
        
        private ICoreRepository _model;
        //private CoreObservableCollection<IKanbanShell> _itemssource = new CoreObservableCollection<IKanbanShell>();

        public ICoreRepository Model
        {
            get => _model;
            set
            {
                _model = value;
                RefreshData(false,true);
            }
        }
        
        public KanbanList()
        {
            _currentStatus = KanbanStatus.Open;
            InitializeComponent();
            ProgressVisible = true;
//            _tasks.ItemsSource = _itemssource;
        }

        protected override void OnAppearing()
        {
            base.OnAppearing();
            _tasks.ItemsSource = _model.Items;
        }

        protected override void OnDisappearing()
        {
            _model.SelectNone();
            _tasks.ItemsSource = null;
            base.OnDisappearing();
        }

        private void RefreshData(bool force, bool async)
        {
            if (async)
                _model.Refresh(force, () => Device.BeginInvokeOnMainThread(RefreshList));
            else
            {
                _model.Refresh(force);
                RefreshList();
            }
        }
        
        private void RefreshList()
        {
            _model.Search((o) => FilterShell(o as IKanbanShell));
            _tasks.ItemsSource = null;
            _tasks.ItemsSource = _model.Items;
            //_itemssource.Clear();
            //_itemssource.ReplaceRange(_model.Items.OfType<IKanbanShell>().Where(FilterShell));
            _tasks.LastUpdated = _model.LastUpdated;
            ProgressVisible = false;
        }

        private String _currentfilter = "";
        
        private void _search_OnTextChanged(object sender, MobileSearchBarTextChangedArgs args)
        {
            _currentfilter = args.Text;
            RefreshList();
        }

        private KanbanStatus _currentStatus;
        private bool FilterShell(IKanbanShell shell)
        {
            bool bOK = shell.Status == _currentStatus;
            
            bOK = bOK && (
                String.IsNullOrWhiteSpace(_currentfilter) 
                    || shell.Summary.ToUpper().Contains(_currentfilter.ToUpper())
                    || shell.Number.ToString().ToUpper().Contains(_currentfilter.ToUpper())
                    || shell.Title.ToUpper().Contains(_currentfilter.ToUpper())
            );
            
            return bOK;
        }

        private void _tasks_OnRefresh(object sender, MobileListRefreshEventArgs args)
        {
            RefreshData(true,false);
        }
        
        private void Kanban_Clicked(object sender, EventArgs e)
        {
            if ((sender as MobileCard)?.BindingContext is IKanbanShell shell)
            {
                var editor = new KanbanEdit() { Item = shell };
                Navigation.PushAsync(editor);
            }
        }
        
        private void CheckBox_Changed(object sender, EventArgs e)
        {
            if ((sender as MobileCheckBox)?.BindingContext is KanbanShell shell)
                _model.ToggleSelection(shell);
        }
        
        private void SelectEmployee(IEnumerable<IKanbanShell> tasks)
        {
            ShowPopup(() => CreateEmployeeSelection("Select Employee", (employee) =>
            {
                foreach (var task in tasks)
                {
                    task.EmployeeID = employee.ID;
                    task.EmployeeName = employee.Name;
                }
                _model.SelectNone();
                RefreshList();
            }));
        }
        
        private async void ChangeStatus(IEnumerable<IKanbanShell> tasks)
        { 
            var index = await MaterialDialog.Instance.SelectActionAsync(Enum.GetNames(typeof(KanbanStatus)));
            if (index > -1)
            {
                foreach (var task in tasks)
                    task.Status = (KanbanStatus)index;
                _model.SelectNone();
                RefreshList();
            }
        }
        
        private View CreateEmployeeSelection(String caption, Action<EmployeeShell> selected)
        {
            SelectionView selection = new SelectionView
            {
                VerticalOptions = LayoutOptions.Fill,
                HorizontalOptions = LayoutOptions.Fill,
                CanSearch = false
            };
            selection.Configure += (sender, args) =>
            {
                args.Columns
                    .BeginUpdate()
                    .Clear()
                    .Add(new MobileGridTextColumn<EmployeeShell>() { Column = x=>x.Name, Width = GridLength.Star, Caption = caption})
                    .EndUpdate();
            };
            selection.Refresh += (sender, args) => App.Data.Employees.Refresh(false);
            selection.SelectionChanged += (sender, args) =>
            {
                selected(args.SelectedItems.FirstOrDefault() as EmployeeShell);
                DismissPopup();
            };
            selection.Load();
            return selection;
        }
        
        private void _reassign_OnClicked(object sender, EventArgs e)
        {
            SelectEmployee(SelectedItems());
        }

        private void _setstatus_OnClicked(object sender, EventArgs e)
        {
            ChangeStatus(SelectedItems());
        }

        private void _selectNone_OnClicked(object sender, EventArgs e)
        {
            _model.SelectNone();
            RefreshList();
        }
        
        private void _selectAll_OnClicked(object sender, EventArgs e)
        {
            _model.SelectAll();
            RefreshList();
        }

        private void _addtask_OnClicked(object sender, MobileMenuButtonClickedEventArgs args)
        {
            var shell = _model.AddItem() as IKanbanShell;
            shell.EmployeeID = App.Data.Me.ID;
            shell.DueDate = DateTime.Today;
            var editor = new KanbanEdit() { Item = shell };
            Navigation.PushAsync(editor);
        }

        private void _tabStrip_OnSelectionChanged(object sender, EventArgs e)
        {
            _currentStatus = (KanbanStatus)_tabStrip.SelectedItem.Index;
            RefreshList();
        }

        private void _selectionmenu_OnAppearing(object sender, EventArgs e)
        {

            bool anyselected = SelectedItems().Any();
            bool anyunselected = UnselectedItems().Any();

            _reassign.IsVisible = anyselected;
            _setstatus.IsVisible = anyselected;
            _selectAll.IsVisible = anyunselected;
            _selectNone.IsVisible = anyselected;
            _separator.IsVisible = (_reassign.IsVisible || _setstatus.IsVisible) && (_selectAll.IsVisible || _selectNone.IsVisible);
            
        }

        private IEnumerable<IKanbanShell> SelectedItems()
        {
            return _model.SelectedItems.OfType<IKanbanShell>();
        }
        
        private IEnumerable<IKanbanShell> UnselectedItems()
        {
            return _model.Items.OfType<IKanbanShell>().Except(_model.SelectedItems.OfType<IKanbanShell>());
        }


    }
}