source: branches/eraser6/pluginsRewrite/Eraser/TaskDragDropHelper.cs @ 2508

/* 
 * $Id$
 * Copyright 2008-2010 The Eraser Project
 * Original Author: Joel Low <lowjoel@users.sourceforge.net>
 * Modified By:
 * 
 * This file is part of Eraser.
 * 
 * Eraser is free software: you can redistribute it and/or modify it under the
 * terms of the GNU General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later
 * version.
 * 
 * Eraser is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
 * A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 * 
 * A copy of the GNU General Public License can be found at
 * <http://www.gnu.org/licenses/>.
 */

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

using System.Globalization;
using System.Windows.Forms;
using System.IO;
using System.Drawing;

using Eraser.Util;
using Eraser.Manager;
using Eraser.Plugins;
using Eraser.Plugins.ExtensionPoints;

namespace Eraser
{
    static class TaskDragDropHelper
    {
        /// <summary>
        /// Parses a list of locations dropped on the target.
        /// </summary>
        /// <param name="e">The event argument.</param>
        /// <param name="recycleBin">A reference to a <typeparamref name="System.Boolean"/> value
        /// which holds whether the recycle bin was dropped.</param>
        /// <returns>The list of file paths dropped.</returns>
        public static ICollection<string> GetFiles(DragEventArgs e, out bool recycleBin)
        {
            //Get the file paths first.
            recycleBin = false;
            List<string> files = e.Data.GetDataPresent(DataFormats.FileDrop) ?
                new List<string>((string[])e.Data.GetData(DataFormats.FileDrop, false)) :
                new List<string>();

            //Then try to see if we have shell locations dropped on us.
            if (e.Data.GetDataPresent("Shell IDList Array"))
            {
                MemoryStream stream = (MemoryStream)e.Data.GetData("Shell IDList Array");
                byte[] buffer = new byte[stream.Length];
                stream.Read(buffer, 0, buffer.Length);
                ShellCIDA cida = new ShellCIDA(buffer);

                if (cida.cidl > 0)
                {
                    for (int i = 1; i <= cida.cidl; ++i)
                    {
                        if (cida.aoffset[i].Guid == Shell.KnownFolderIDs.RecycleBin)
                        {
                            recycleBin = true;
                        }
                    }
                }
            }

            return files;
        }

        /// <summary>
        /// Parses a list of locations dropped on the target, converting them to the appropriate
        /// IErasureTarget instance.
        /// </summary>
        /// <param name="e">The event argument.</param>
        /// <returns>A list of erasure targets which will erase all the files and directories
        /// as described by the drag-and-drop operation.</returns>
        public static ICollection<IErasureTarget> GetTargets(DragEventArgs e)
        {
            ICollection<IErasureTarget> result = new List<IErasureTarget>();
            foreach (IErasureTarget target in Host.Instance.ErasureTargetFactories)
            {
                //Skip targets not supporting IDragAndDropConfigurer
                if (!(target.Configurer is IDragAndDropConfigurerFactory<IErasureTarget>))
                    continue;

                IDragAndDropConfigurerFactory<IErasureTarget> configurer =
                    (IDragAndDropConfigurerFactory<IErasureTarget>)target.Configurer;
                foreach (IErasureTarget newTarget in configurer.ProcessArgument(e))
                    result.Add(newTarget);
            }

            return result;
        }

        /// <summary>
        /// Handles the drag enter event.
        /// </summary>
        /// <param name="sender">The sender for the event.</param>
        /// <param name="e">Event argument for the drag & drop operation.</param>
        public static void OnDragEnter(Control control, DragEventArgs e,
            string descriptionMessage, ICollection<string> items)
        {
            //Replace the C# {0} with the %1 used by Windows.
            descriptionMessage = descriptionMessage.Replace("{0}", "%1");

            string descriptionInsert = string.Empty;
            string descriptionItemFormat = S._("{0}, ");
            foreach (string item in items)
            {
                if (descriptionInsert.Length < 259 &&
                    (descriptionInsert.Length < 3 || descriptionInsert.Substring(descriptionInsert.Length - 3) != "..."))
                {
                    string append = string.Format(CultureInfo.InvariantCulture,
                        descriptionItemFormat, item);

                    if (descriptionInsert.Length + append.Length > 259)
                        descriptionInsert += ".....";
                    else
                        descriptionInsert += append;
                }
            }

            if (!string.IsNullOrEmpty(descriptionInsert))
                descriptionInsert = descriptionInsert.Remove(descriptionInsert.Length - 2);

            if (e.Data.GetDataPresent("DragImageBits"))
                DropTargetHelper.DragEnter(control, e.Data, new Point(e.X, e.Y), e.Effect,
                    descriptionMessage, descriptionInsert);
        }

        public static void OnDrop(DragEventArgs e)
        {
            DropTargetHelper.Drop(e.Data, new Point(e.X, e.Y), e.Effect);
        }
    }
}