using System;
using System.Collections.Generic;
using System.Text;
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.Shapes;

namespace PixelLab.ToolBox
{
    public class IndexingStackPanel : StackPanel
    {
        #region Index (Attached Dependency Property)

        public static int GetIndex(DependencyObject obj)
        {
            return (int)obj.GetValue(IndexProperty);
        }

        public static void SetIndex(DependencyObject obj, int value)
        {
            obj.SetValue(IndexProperty, value);
        }

        public static readonly DependencyProperty IndexProperty =
            DependencyProperty.RegisterAttached("Index", typeof(int), typeof(IndexingStackPanel), new UIPropertyMetadata(default(int)));

        #endregion

        #region SelectionLocation

        public static SelectionLocation GetSelectionLocation(DependencyObject obj)
        {
            return (SelectionLocation)obj.GetValue(SelectionLocationProperty);
        }

        public static void SetSelectionLocation(DependencyObject obj, SelectionLocation value)
        {
            obj.SetValue(SelectionLocationProperty, value);
        }

        public static readonly DependencyProperty SelectionLocationProperty =
            DependencyProperty.RegisterAttached("SelectionLocation", typeof(SelectionLocation), typeof(IndexingStackPanel), new UIPropertyMetadata(SelectionLocation.None));

        #endregion

        #region StackLocation (Attached Dependency Property)

        public static StackLocation GetStackLocation(DependencyObject obj)
        {
            return (StackLocation)obj.GetValue(StackLocationProperty);
        }

        public static void SetStackLocation(DependencyObject obj, StackLocation value)
        {
            obj.SetValue(StackLocationProperty, value);
        }

        public static readonly DependencyProperty StackLocationProperty =
            DependencyProperty.RegisterAttached("StackLocation", typeof(StackLocation), typeof(IndexingStackPanel), new UIPropertyMetadata(default(StackLocation)));

        #endregion

        #region IndexOddEven (Attached DependencyProperty)

        public static IndexOddEven GetIndexOddEven(DependencyObject obj)
        {
            return (IndexOddEven)obj.GetValue(IndexOddEvenProperty);
        }

        public static void SetIndexOddEven(DependencyObject obj, IndexOddEven value)
        {
            obj.SetValue(IndexOddEvenProperty, value);
        }

        public static readonly DependencyProperty IndexOddEvenProperty =
            DependencyProperty.RegisterAttached("IndexOddEven", typeof(IndexOddEven), typeof(IndexingStackPanel), new UIPropertyMetadata(default(IndexOddEven)));


        #endregion

        #region Overrides

        protected override void OnIsItemsHostChanged(bool oldIsItemsHost, bool newIsItemsHost)
        {
            if (this.IsItemsHost)
            {
                Selector selectorParent = this.TemplatedParent as Selector;

                if (selectorParent != null)
                {
                    selectorParent.SelectionChanged += new SelectionChangedEventHandler(ParentSelectionChanged);
                }
            }

            base.OnIsItemsHostChanged(oldIsItemsHost, newIsItemsHost);
        }

        UIElement selectedElement = null;

        void ParentSelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            Selector selectorParent = sender as Selector;

            if (selectorParent != null)
            {
                if (selectorParent == this.TemplatedParent)
                {
                    bool foundSelected = false;

                    foreach (object item in selectorParent.Items)
                    {
                        UIElement element = (selectorParent.ItemContainerGenerator.ContainerFromItem(item) as UIElement);
                        if (element != null)
                        {
                            if (e.AddedItems.Contains(item))
                            {
                                element.SetValue(SelectionLocationProperty, SelectionLocation.Selected);
                                foundSelected = true;
                            }
                            else if (foundSelected)
                            {
                                element.SetValue(SelectionLocationProperty, SelectionLocation.After);
                            }
                            else
                            {
                                element.SetValue(SelectionLocationProperty, SelectionLocation.Before);
                            }
                        }
                    }
                }
            }
        }


        protected override Size MeasureOverride(Size constraint)
        {
            int index = 0;
            bool isEven = true;
            bool foundSelected = false;

            foreach (UIElement element in this.Children)
            {

                // StackLocation

                if (Children.Count - 1 == 0)
                {
                    element.SetValue(StackLocationProperty, StackLocation.FirstAndLast);
                }
                else if (index == 0)
                {
                    element.SetValue(StackLocationProperty, StackLocation.First);
                }
                else if (index == Children.Count - 1)
                {
                    element.SetValue(StackLocationProperty, StackLocation.Last);
                }
                else
                {
                    element.SetValue(StackLocationProperty, StackLocation.Middle);
                }

                // IndexOddEven

                if (isEven)
                {
                    element.SetValue(IndexOddEvenProperty, IndexOddEven.Even);
                }
                else
                {
                    element.SetValue(IndexOddEvenProperty, IndexOddEven.Odd);
                }

                element.SetValue(IndexProperty, index);
                index++;

            }

            return base.MeasureOverride(constraint);
        }

        #endregion
    }

    public enum StackLocation
    {
        First,
        Middle,
        Last,
        FirstAndLast
    }

    public enum SelectionLocation
    {
        None,
        Before,
        Selected,
        After
    }

    public enum IndexOddEven
    {
        Odd,
        Even
    }
}