// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
//
// Description:
//      A base class which can copy a unicode text to the IDataObject.
//      It also can get the unicode text from the IDataObject and create a corresponding textbox.
//
 
using System.Windows;
using System.Windows.Controls;
 
namespace MS.Internal.Ink
{
    internal class TextClipboardData : ElementsClipboardData
    {
        //-------------------------------------------------------------------------------
        //
        // Constructors
        //
        //-------------------------------------------------------------------------------
 
        #region Constructors
 
        // The default constructor
        internal TextClipboardData() : this(null) {}
 
        // The constructor with a string as argument
        internal TextClipboardData(string text)
        {
            _text = text;
        }
 
        #endregion Constructors
 
        // Checks if the data can be pasted.
        internal override bool CanPaste(IDataObject dataObject)
        {
            return ( dataObject.GetDataPresent(DataFormats.UnicodeText, false)
                        || dataObject.GetDataPresent(DataFormats.Text, false)
                        || dataObject.GetDataPresent(DataFormats.OemText, false) );
        }
 
        //-------------------------------------------------------------------------------
        //
        // Protected Methods
        //
        //-------------------------------------------------------------------------------
 
        #region Protected Methods
 
        // Checks if the data can be copied.
        protected override bool CanCopy()
        {
            return !string.IsNullOrEmpty(_text);
        }
 
        // Copy the text to the IDataObject
        protected override void DoCopy(IDataObject dataObject)
        {
            // Put the text to the clipboard
            dataObject.SetData(DataFormats.UnicodeText, _text, true);
        }
 
        // Retrieves the text from the IDataObject instance.
        // Then create a textbox with the text data.
        protected override void DoPaste(IDataObject dataObject)
        {
            ElementList = new List<UIElement>();
        
            // Get the string from the data object.
            string text = dataObject.GetData(DataFormats.UnicodeText, true) as string;
 
            if ( String.IsNullOrEmpty(text) )
            {
                // OemText can be retrieved as CF_TEXT.
                text = dataObject.GetData(DataFormats.Text, true) as string;
            }
 
            if ( !String.IsNullOrEmpty(text) )
            {
                // Now, create a text box and set the text to it.
                TextBox textBox = new TextBox
                {
                    Text = text,
                    TextWrapping = TextWrapping.Wrap
                };
 
                // Add the textbox to the internal array list.
                ElementList.Add(textBox);
            }
}
 
        #endregion Protected Methods
 
        //-------------------------------------------------------------------------------
        //
        // Private Fields
        //
        //-------------------------------------------------------------------------------
 
        #region Private Fields
 
        private string      _text;
 
        #endregion Private Fields
    }
}