using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using Tango.Core.Commands;
using Tango.Core.EventArguments;
using Tango.Core.ExtensionMethods;

namespace Tango.Touch.Controls
{
    public class TouchAutoComplete : TouchInput
    {
        private TextBox _textBox;
        private Popup _popup;
        private TouchListBox _listbox;

        public String Text
        {
            get { return (String)GetValue(TextProperty); }
            set { SetValue(TextProperty, value); }
        }
        public static readonly DependencyProperty TextProperty =
            DependencyProperty.Register("Text", typeof(String), typeof(TouchAutoComplete), new FrameworkPropertyMetadata(null, FrameworkPropertyMetadataOptions.BindsTwoWayByDefault));

        public String Watermark
        {
            get { return (String)GetValue(WatermarkProperty); }
            set { SetValue(WatermarkProperty, value); }
        }
        public static readonly DependencyProperty WatermarkProperty =
            DependencyProperty.Register("Watermark", typeof(String), typeof(TouchAutoComplete), new PropertyMetadata(null));

        public IList ItemsSource
        {
            get { return (IList)GetValue(ItemsSourceProperty); }
            set { SetValue(ItemsSourceProperty, value); }
        }
        public static readonly DependencyProperty ItemsSourceProperty =
            DependencyProperty.Register("ItemsSource", typeof(IList), typeof(TouchAutoComplete), new PropertyMetadata(null));

        public IList EffectiveItemsSource
        {
            get { return (IList)GetValue(EffectiveItemsSourceProperty); }
            private set { SetValue(EffectiveItemsSourceProperty, value); }
        }
        public static readonly DependencyProperty EffectiveItemsSourceProperty =
            DependencyProperty.Register("EffectiveItemsSource", typeof(IList), typeof(TouchAutoComplete), new PropertyMetadata(null));

        public IAutoCompleteProvider AutoCompleteProvider
        {
            get { return (IAutoCompleteProvider)GetValue(AutoCompleteProviderProperty); }
            set { SetValue(AutoCompleteProviderProperty, value); }
        }
        public static readonly DependencyProperty AutoCompleteProviderProperty =
            DependencyProperty.Register("AutoCompleteProvider", typeof(IAutoCompleteProvider), typeof(TouchAutoComplete), new PropertyMetadata(null));

        public object SelectedItem
        {
            get { return (object)GetValue(SelectedItemProperty); }
            set { SetValue(SelectedItemProperty, value); }
        }
        public static readonly DependencyProperty SelectedItemProperty =
            DependencyProperty.Register("SelectedItem", typeof(object), typeof(TouchAutoComplete), new PropertyMetadata(null, (d, e) => (d as TouchAutoComplete).OnSelectedItemChanged()));

        public String DisplayMemberPath
        {
            get { return (String)GetValue(DisplayMemberPathProperty); }
            set { SetValue(DisplayMemberPathProperty, value); }
        }
        public static readonly DependencyProperty DisplayMemberPathProperty =
            DependencyProperty.Register("DisplayMemberPath", typeof(String), typeof(TouchAutoComplete), new PropertyMetadata(null));

        public DataTemplate ItemTemplate
        {
            get { return (DataTemplate)GetValue(ItemTemplateProperty); }
            set { SetValue(ItemTemplateProperty, value); }
        }
        public static readonly DependencyProperty ItemTemplateProperty =
            DependencyProperty.Register("ItemTemplate", typeof(DataTemplate), typeof(TouchAutoComplete), new PropertyMetadata(null));

        public RelayCommand ItemSelectedCommand
        {
            get { return (RelayCommand)GetValue(ItemSelectedCommandProperty); }
            private set { SetValue(ItemSelectedCommandProperty, value); }
        }
        public static readonly DependencyProperty ItemSelectedCommandProperty =
            DependencyProperty.Register("ItemSelectedCommand", typeof(RelayCommand), typeof(TouchAutoComplete), new PropertyMetadata(null));

        public double PopupHeight
        {
            get { return (double)GetValue(PopupHeightProperty); }
            set { SetValue(PopupHeightProperty, value); }
        }
        public static readonly DependencyProperty PopupHeightProperty =
            DependencyProperty.Register("PopupHeight", typeof(double), typeof(TouchAutoComplete), new PropertyMetadata(200.0));

        public bool ForceItemSelection
        {
            get { return (bool)GetValue(ForceItemSelectionProperty); }
            set { SetValue(ForceItemSelectionProperty, value); }
        }
        public static readonly DependencyProperty ForceItemSelectionProperty =
            DependencyProperty.Register("ForceItemSelection", typeof(bool), typeof(TouchAutoComplete), new PropertyMetadata(true));



        public TouchAutoComplete()
        {
            //AutoCompleteProvider = new AutoCompleteProvider<Object>((obj, filter) => { return obj.ToString().ToLower().StartsWith(filter.ToLower()); });
            ItemSelectedCommand = new RelayCommand(() => OnSelectedItemChanged());
        }

        public override void OnApplyTemplate()
        {
            base.OnApplyTemplate();

            _textBox = GetTemplateChild("PART_TextBox") as TextBox;
            _popup = GetTemplateChild("PART_Popup") as Popup;
            _listbox = GetTemplateChild("PART_ListBox") as TouchListBox;

            _popup.RegisterForMouseOrTouchDown(OnPopupMouseDown);

            _textBox.PreviewKeyUp += _textBox_PreviewKeyUp;
            _textBox.GotFocus += _textBox_GotFocus;
            _textBox.LostFocus += _textBox_LostFocus;

            OnSelectedItemChanged();
        }

        private void OnPopupMouseDown(object sender, MouseOrTouchEventArgs e)
        {
            e.Handled = true;
        }

        private void _textBox_LostFocus(object sender, RoutedEventArgs e)
        {
            _popup.IsOpen = false;

            if (ForceItemSelection)
            {
                if (EffectiveItemsSource != null && EffectiveItemsSource.Count > 0 && SelectedItem == null)
                {
                    SelectedItem = EffectiveItemsSource[0];

                    var binding = BindingOperations.GetBindingExpressionBase(this, SelectedItemProperty);

                    if (binding != null)
                    {
                        binding.UpdateSource();
                    }
                }
            }
        }

        private void _textBox_GotFocus(object sender, RoutedEventArgs e)
        {
            if (Text != null)
            {
                _textBox.CaretIndex = _textBox.Text.Length;
            }
        }

        private void _textBox_PreviewKeyUp(object sender, KeyEventArgs e)
        {
            if (AutoCompleteProvider != null && ItemsSource != null)
            {
                EffectiveItemsSource = AutoCompleteProvider.Filter(ItemsSource, Text);

                SelectedItem = null;


                if (EffectiveItemsSource.Count > 0)
                {
                    _popup.IsOpen = true;
                    _listbox.ScrollViewer.ScrollToTop();
                }
                else
                {
                    _popup.IsOpen = false;
                }
            }
        }

        private void OnSelectedItemChanged()
        {
            if (SelectedItem != null && _textBox != null)
            {
                Text = SelectedItem.GetPropertyValueByPath(DisplayMemberPath).ToString();

                if (Text != null)
                {
                    _textBox.CaretIndex = _textBox.Text.Length;
                }
            }
            else if (_textBox != null)
            {
                _textBox.Text = null;
            }

            if (_popup != null)
            {
                _popup.IsOpen = false;
            }
        }

        static TouchAutoComplete()
        {
            DefaultStyleKeyProperty.OverrideMetadata(typeof(TouchAutoComplete), new FrameworkPropertyMetadata(typeof(TouchAutoComplete)));
        }
    }
}