using System;
using System.Diagnostics;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using System.Windows.Input;
using System.Xml;

namespace Chronos.Presentation.DragAndDrop
{
    public sealed class ListBoxDragDropDataProvider : IDataDropObjectProvider
    {
        #region · Fields ·

        private ListBox list;

        #endregion

        #region · Properties ·

        public DragDropProviderActions SupportedActions
        {
            get
            {
                return DragDropProviderActions.Data | 
                       DragDropProviderActions.Visual | 
                       DragDropProviderActions.Unparent | 
                       DragDropProviderActions.MultiFormatData;
            }
        }

        #endregion

        #region · Constructors ·

        public ListBoxDragDropDataProvider(ListBox list)
        {
            this.list = list;
        }

        #endregion

        #region · IDataDropObjectProvider Members ·

        public void AppendData (ref IDataObject data, MouseEventArgs e)
        {
            if (!(this.list.InputHitTest(e.GetPosition(e.OriginalSource as UIElement)) is ListBox) 
                && !(this.list.InputHitTest(e.GetPosition(e.OriginalSource as UIElement)) is ScrollViewer)
                && !(e.OriginalSource is Thumb))
            {
                object o = this.list.SelectedItem;

                // This is cheating .. just for an example's sake.. 
                Debug.Assert(!data.GetDataPresent(DataFormats.Text));

                if (o.GetType() == typeof(XmlElement))
                {
                    data.SetData(DataFormats.Text, ((XmlElement)o).OuterXml);
                }
                else
                {
                    data.SetData(DataFormats.Text, o.ToString());
                }

                Debug.Assert(!data.GetDataPresent(o.GetType().ToString()));

                data.SetData(o.GetType().ToString(), o);
            }
            else
            {
                data = null;
            }
        }

        public object GetData()
        {
            return this.list.SelectedItem;
        } 

        public UIElement GetVisual(MouseEventArgs e)
        {
            return this.list.ItemContainerGenerator.ContainerFromItem(this.list.SelectedItem) as UIElement;
        }

        public void GiveFeedback(System.Windows.GiveFeedbackEventArgs args)
        {
            throw new NotImplementedException("Forgot to check the Supported actions??"); 
        }

        public void ContinueDrag(System.Windows.QueryContinueDragEventArgs args)
        {
            throw new NotImplementedException("Forgot to check the Supported actions??"); 
        }

        public bool UnParent()
        {
            // We are passing data, nothing to unparent 
            throw new NotImplementedException("We are passing data, nothing to unparent... what up "); 
        }

        #endregion
    }
}