mcs/class/Managed.Windows.Forms/System.Windows.Forms/X11Dnd.cs

   1 // Permission is hereby granted, free of charge, to any person obtaining
   2 // a copy of this software and associated documentation files (the
   3 // "Software"), to deal in the Software without restriction, including
   4 // without limitation the rights to use, copy, modify, merge, publish,
   5 // distribute, sublicense, and/or sell copies of the Software, and to
   6 // permit persons to whom the Software is furnished to do so, subject to
   7 // the following conditions:
   8 //
   9 // The above copyright notice and this permission notice shall be
  10 // included in all copies or substantial portions of the Software.
  11 //
  12 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  13 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  14 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  15 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  16 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  17 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  18 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  19 //
  20 // Copyright (c) 2005 Novell, Inc.
  21 //
  22 // Authors:
  23 //      Jackson Harper (jackson@ximian.com)
  24 //
  25 //
  26
  27
  28 using System;
  29 using System.IO;
  30 using System.Text;
  31 using System.Drawing;
  32 using System.Collections;
  33 using System.Runtime.Serialization;
  34 using System.Runtime.InteropServices;
  35 using System.Runtime.Serialization.Formatters.Binary;
  36
  37 namespace System.Windows.Forms {
  38
  39         internal class X11Dnd {
  40
  41                 private enum State {
  42                         Accepting,
  43                         Dragging
  44                 }
  45
  46                 private enum DragState {
  47                         None,
  48                         Beginning,
  49                         Dragging,
  50                         Entered
  51                 }
  52
  53                 private interface IDataConverter {
  54                         void GetData (X11Dnd dnd, DataObject data, ref XEvent xevent);
  55                         void SetData (X11Dnd dnd, object data, ref XEvent xevent);
  56                 }
  57
  58                 private delegate void MimeConverter (IntPtr dsp,
  59                                 DataObject data, ref XEvent xevent);
  60
  61                 private class MimeHandler {
  62                         public string Name;
  63                         public IntPtr Type;
  64                         public IntPtr NonProtocol;
  65                         public IDataConverter Converter;
  66
  67                         public MimeHandler (string name, IDataConverter converter)
  68                         {
  69                                 Name = name;
  70                                 Converter = converter;
  71                         }
  72
  73                         public override string ToString ()
  74                         {
  75                                 return "MimeHandler {" + Name + "}";
  76                         }
  77                 }
  78
  79                 private MimeHandler [] MimeHandlers = {
  80 //                        new MimeHandler ("WCF_DIB"),
  81 //                        new MimeHandler ("image/gif", new MimeConverter (ImageConverter)),
  82 //                      new MimeHandler ("text/rtf", new MimeConverter (RtfConverter)),
  83 //                      new MimeHandler ("text/richtext", new MimeConverter (RtfConverter)),
  84
  85                         new MimeHandler ("text/plain", new TextConverter ()),
  86                         new MimeHandler ("text/html", new HtmlConverter ()),
  87                         new MimeHandler ("text/uri-list", new UriListConverter ()),
  88                         new MimeHandler ("application/x-mono-serialized-object",
  89                                         new SerializedObjectConverter ())
  90                 };
  91
  92                 private class SerializedObjectConverter : IDataConverter {
  93
  94                         public void GetData (X11Dnd dnd, DataObject data, ref XEvent xevent)
  95                         {
  96                                 MemoryStream stream = dnd.GetData (ref xevent);
  97                                 BinaryFormatter bf = new BinaryFormatter ();
  98
  99                                 if (stream.Length == 0)
 100                                         return;
 101
 102                                 stream.Seek (0, 0);
 103                                 object obj = bf.Deserialize (stream);
 104                                 data.SetData (obj);
 105                         }
 106
 107                         public void SetData (X11Dnd dnd, object data, ref XEvent xevent)
 108                         {
 109                                 if (data == null)
 110                                         return;
 111
 112                                 MemoryStream stream = new MemoryStream ();
 113                                 BinaryFormatter bf = new BinaryFormatter ();
 114
 115                                 bf.Serialize (stream, data);
 116
 117                                 IntPtr buffer = Marshal.AllocHGlobal ((int) stream.Length);
 118                                 stream.Seek (0, 0);
 119
 120                                 for (int i = 0; i < stream.Length; i++) {
 121                                         Marshal.WriteByte (buffer, i, (byte) stream.ReadByte ());
 122                                 }
 123
 124                                 dnd.SetProperty (ref xevent, buffer, (int) stream.Length);
 125                         }
 126                 }
 127
 128                 private class HtmlConverter : IDataConverter {
 129
 130                         public void GetData (X11Dnd dnd, DataObject data, ref XEvent xevent)
 131                         {
 132                                 string text = dnd.GetText (ref xevent, false);
 133                                 if (text == null)
 134                                         return;
 135                                 data.SetData (DataFormats.Text, text);
 136                                 data.SetData (DataFormats.UnicodeText, text);
 137                         }
 138
 139                         public void SetData (X11Dnd dnd, object data, ref XEvent xevent)
 140                         {
 141                                 IntPtr buffer;
 142                                 int len;
 143                                 string str = data as string;
 144
 145                                 if (str == null)
 146                                         return;
 147
 148                                 if (xevent.SelectionRequestEvent.target == (IntPtr)Atom.XA_STRING) {
 149                                         byte [] bytes = Encoding.ASCII.GetBytes (str);
 150                                         buffer = Marshal.AllocHGlobal (bytes.Length);
 151                                         len = bytes.Length;
 152                                         for (int i = 0; i < len; i++)
 153                                                 Marshal.WriteByte (buffer, i, bytes [i]);
 154                                 } else {
 155                                         buffer = Marshal.StringToHGlobalAnsi (str);
 156                                         len = 0;
 157                                         while (Marshal.ReadByte (buffer, len) != 0)
 158                                                 len++;
 159                                 }
 160
 161                                 dnd.SetProperty (ref xevent, buffer, len);
 162
 163                                 Marshal.FreeHGlobal (buffer);
 164                         }
 165                 }
 166
 167                 private class TextConverter : IDataConverter {
 168
 169                         public void GetData (X11Dnd dnd, DataObject data, ref XEvent xevent)
 170                         {
 171                                 string text = dnd.GetText (ref xevent, true);
 172                                 if (text == null)
 173                                         return;
 174                                 data.SetData (DataFormats.Text, text);
 175                                 data.SetData (DataFormats.UnicodeText, text);
 176                         }
 177
 178                         public void SetData (X11Dnd dnd, object data, ref XEvent xevent)
 179                         {
 180                                 IntPtr buffer;
 181                                 int len;
 182                                 string str = data as string;
 183
 184                                 if (data == null)
 185                                         return;
 186
 187                                 if (xevent.SelectionRequestEvent.target == (IntPtr)Atom.XA_STRING) {
 188                                         byte [] bytes = Encoding.ASCII.GetBytes (str);
 189                                         buffer = Marshal.AllocHGlobal (bytes.Length);
 190                                         len = bytes.Length;
 191                                         for (int i = 0; i < len; i++)
 192                                                 Marshal.WriteByte (buffer, i, bytes [i]);
 193                                 } else {
 194                                         buffer = Marshal.StringToHGlobalAnsi (str);
 195                                         len = 0;
 196                                         while (Marshal.ReadByte (buffer, len) != 0)
 197                                                 len++;
 198                                 }
 199
 200                                 dnd.SetProperty (ref xevent, buffer, len);
 201
 202                                 Marshal.FreeHGlobal (buffer);
 203                         }
 204                 }
 205
 206                 private class UriListConverter : IDataConverter {
 207
 208                         public void GetData (X11Dnd dnd, DataObject data, ref XEvent xevent)
 209                         {
 210                                 string text = dnd.GetText (ref xevent, false);
 211                                 if (text == null)
 212                                         return;
 213
 214                                 // TODO: Do this in a loop instead of just splitting
 215                                 ArrayList uri_list = new ArrayList ();
 216                                 string [] lines = text.Split (new char [] { '\r', '\n' });
 217                                 foreach (string line in lines) {
 218                                         // # is a comment line (see RFC 2483)
 219                                         if (line.StartsWith ("#"))
 220                                                 continue;
 221                                         try {
 222                                                 Uri uri = new Uri (line);
 223                                                 uri_list.Add (uri.LocalPath);
 224                                         } catch { }
 225                                 }
 226
 227                                 string [] l = (string []) uri_list.ToArray (typeof (string));
 228                                 if (l.Length < 1)
 229                                         return;
 230                                 data.SetData (DataFormats.FileDrop, l);
 231                                 data.SetData ("FileName", l [0]);
 232                                 data.SetData ("FileNameW", l [0]);
 233                         }
 234
 235                         public void SetData (X11Dnd dnd, object data, ref XEvent xevent)
 236                         {
 237                                 string [] uri_list = data as string [];
 238
 239                                 if (uri_list == null)
 240                                         return;
 241
 242                                 StringBuilder res = new StringBuilder ();
 243                                 foreach (string uri_str in uri_list) {
 244                                         Uri uri = new Uri (uri_str);
 245                                         res.Append (uri.ToString ());
 246                                         res.Append ("\r\n");
 247                                 }
 248
 249                                 IntPtr buffer = Marshal.StringToHGlobalAnsi ((string) data);
 250                                 int len = 0;
 251                                 while (Marshal.ReadByte (buffer, len) != 0)
 252                                         len++;
 253
 254                                 dnd.SetProperty (ref xevent, buffer, len);
 255                         }
 256                 }
 257
 258                 private class DragData {
 259                         public IntPtr Window;
 260                         public DragState State;
 261                         public object Data;
 262                         public IntPtr Action;
 263                         public IntPtr [] SupportedTypes;
 264                         public MouseButtons MouseState;
 265
 266                         public IntPtr LastWindow;
 267                         public IntPtr LastTopLevel;
 268
 269                         public bool WillAccept;
 270
 271                         public void Reset ()
 272                         {
 273                                 State = DragState.None;
 274                                 Data = null;
 275                                 SupportedTypes = null;
 276                                 WillAccept = false;
 277                         }
 278                 }
 279
 280                 private class DropData {
 281
 282                 }
 283
 284                 // This version seems to be the most common
 285                 private static readonly IntPtr [] XdndVersion = new IntPtr [] { new IntPtr (4) };
 286
 287                 private IntPtr display;
 288                 private DragData drag_data;
 289
 290                 private IntPtr XdndAware;
 291                 private IntPtr XdndSelection;
 292                 private IntPtr XdndEnter;
 293                 private IntPtr XdndLeave;
 294                 private IntPtr XdndPosition;
 295                 private IntPtr XdndDrop;
 296                 private IntPtr XdndFinished;
 297                 private IntPtr XdndStatus;
 298                 private IntPtr XdndTypeList;
 299                 private IntPtr XdndActionCopy;
 300                 private IntPtr XdndActionMove;
 301                 private IntPtr XdndActionLink;
 302                 //private IntPtr XdndActionPrivate;
 303                 //private IntPtr XdndActionList;
 304                 //private IntPtr XdndActionDescription;
 305                 //private IntPtr XdndActionAsk;
 306
 307                 //private State state;
 308
 309                 private int converts_pending;
 310                 private bool position_recieved;
 311                 private bool status_sent;
 312                 private IntPtr target;
 313                 private IntPtr source;
 314                 private IntPtr toplevel;
 315                 private DataObject data;
 316
 317                 private Control control;
 318                 private int pos_x, pos_y;
 319                 private DragDropEffects allowed;
 320                 private DragEventArgs drag_event;
 321
 322                 private Cursor CursorNo;
 323                 private Cursor CursorCopy;
 324                 private Cursor CursorMove;
 325                 private Cursor CursorLink;
 326                 // check out the TODO below
 327                 //private IntPtr CurrentCursorHandle;
 328
 329                 public X11Dnd (IntPtr display)
 330                 {
 331                         this.display = display;
 332                         Init ();
 333                 }
 334
 335                 public bool InDrag()
 336                 {
 337                         if (drag_data == null)
 338                                 return false;
 339                         return drag_data.State != DragState.None;
 340                 }
 341
 342                 public void SetAllowDrop (Hwnd hwnd, bool allow)
 343                 {
 344                         int[] atoms;
 345
 346                         if (hwnd.allow_drop == allow)
 347                                 return;
 348
 349                         atoms = new int[XdndVersion.Length];
 350                         for (int i = 0; i < XdndVersion.Length; i++) {
 351                                 atoms[i] = XdndVersion[i].ToInt32();
 352                         }
 353
 354                         XplatUIX11.XChangeProperty (display, hwnd.whole_window, XdndAware,
 355                                         (IntPtr) Atom.XA_ATOM, 32,
 356                                         PropertyMode.Replace, atoms, allow ? 1 : 0);
 357                         hwnd.allow_drop = allow;
 358                 }
 359
 360                 public DragDropEffects StartDrag (IntPtr handle, object data,
 361                                 DragDropEffects allowed_effects)
 362                 {
 363                         drag_data = new DragData ();
 364                         drag_data.Window = handle;
 365                         drag_data.State = DragState.Beginning;
 366                         drag_data.MouseState = XplatUIX11.MouseState;
 367                         drag_data.Data = data;
 368                         drag_data.SupportedTypes = DetermineSupportedTypes (data);
 369
 370                         drag_data.Action = ActionFromEffect (allowed_effects);
 371
 372                         if (CursorNo == null) {
 373                                 // Make sure the cursors are created
 374                                 CursorNo = new Cursor (typeof (X11Dnd), "DnDNo.cur");
 375                                 CursorCopy = new Cursor (typeof (X11Dnd), "DnDCopy.cur");
 376                                 CursorMove = new Cursor (typeof (X11Dnd), "DnDMove.cur");
 377                                 CursorLink = new Cursor (typeof (X11Dnd), "DnDLink.cur");
 378                         }
 379
 380                         drag_data.LastTopLevel = IntPtr.Zero;
 381                         return DragDropEffects.Copy;
 382                 }
 383
 384                 public void HandleButtonRelease (ref XEvent xevent)
 385                 {
 386                         if (drag_data == null)
 387                                 return;
 388
 389                         if (!((drag_data.MouseState == MouseButtons.Left &&
 390                                               xevent.ButtonEvent.button == 1) ||
 391                                             (drag_data.MouseState == MouseButtons.Right &&
 392                                                             xevent.ButtonEvent.button == 3)))
 393                                 return;
 394
 395                         if (drag_data.State == DragState.Beginning) {
 396                                 //state = State.Accepting;
 397                         } else if (drag_data.State != DragState.None) {
 398
 399                                 if (drag_data.WillAccept) {
 400                                         SendDrop (drag_data.LastTopLevel, xevent.AnyEvent.window,
 401                                                         xevent.ButtonEvent.time);
 402                                 }
 403
 404                                 XplatUIX11.XUngrabPointer (display, IntPtr.Zero);
 405                                 drag_data.State = DragState.None;
 406                                 // WE can't reset the drag data yet as it is still
 407                                 // most likely going to be used by the SelectionRequest
 408                                 // handlers
 409                         }
 410                 }
 411
 412                 public bool HandleMotionNotify (ref XEvent xevent)
 413                 {
 414                         if (drag_data == null)
 415                                 return false;
 416
 417                         if (drag_data.State == DragState.Beginning) {
 418                                 int suc;
 419
 420                                 drag_data.State = DragState.Dragging;
 421
 422                                 suc = XplatUIX11.XSetSelectionOwner (display, XdndSelection,
 423                                                 drag_data.Window,
 424                                                 xevent.ButtonEvent.time);
 425
 426                                 if (suc == 0) {
 427                                         Console.Error.WriteLine ("Could not take ownership of XdndSelection aborting drag.");
 428                                         drag_data.Reset ();
 429                                         return false;
 430                                 }
 431
 432                                 suc = XplatUIX11.XGrabPointer (display, xevent.AnyEvent.window,
 433                                                 false,
 434                                                 EventMask.ButtonMotionMask |
 435                                                 EventMask.PointerMotionMask |
 436                                                 EventMask.ButtonPressMask |
 437                                                 EventMask.ButtonReleaseMask,
 438                                                 GrabMode.GrabModeAsync,
 439                                                 GrabMode.GrabModeAsync,
 440                                                 IntPtr.Zero, IntPtr.Zero/*CursorCopy.Handle*/, IntPtr.Zero);
 441
 442                                 if (suc != 0) {
 443                                         Console.Error.WriteLine ("Could not grab pointer aborting drag.");
 444                                         drag_data.Reset ();
 445                                         return false;
 446                                 }
 447
 448                                 drag_data.State = DragState.Dragging;
 449                         } else if (drag_data.State != DragState.None) {
 450                                 bool dnd_aware = false;
 451                                 IntPtr toplevel = IntPtr.Zero;
 452                                 IntPtr window = XplatUIX11.RootWindowHandle;
 453
 454                                 IntPtr root, child;
 455                                 int x_temp, y_temp;
 456                                 int mask_return;
 457
 458                                 while (XplatUIX11.XQueryPointer (display,
 459                                                        window,
 460                                                        out root, out child,
 461                                                        out x_temp, out y_temp,
 462                                                        out xevent.MotionEvent.x,
 463                                                        out xevent.MotionEvent.y,
 464                                                        out mask_return)) {
 465
 466                                         if (!dnd_aware) {
 467                                                 dnd_aware = IsWindowDndAware (window);
 468                                                 if (dnd_aware) {
 469                                                         toplevel = window;
 470                                                         xevent.MotionEvent.x_root = x_temp;
 471                                                         xevent.MotionEvent.y_root = y_temp;
 472                                                 }
 473                                         }
 474
 475                                         if (child == IntPtr.Zero)
 476                                                 break;
 477
 478                                         window = child;
 479                                 }
 480
 481                                 if (window != drag_data.LastWindow && drag_data.State == DragState.Entered) {
 482                                         drag_data.State = DragState.Dragging;
 483
 484                                         // TODO: Send a Leave if this is an MWF window
 485
 486                                         if (toplevel != drag_data.LastTopLevel)
 487                                                 SendLeave (drag_data.LastTopLevel, xevent.MotionEvent.window);
 488                                 }
 489
 490                                 drag_data.State = DragState.Entered;
 491                                 if (toplevel != drag_data.LastTopLevel) {
 492                                         // Entering a new toplevel window
 493                                         SendEnter (toplevel, drag_data.Window, drag_data.SupportedTypes);
 494                                 } else {
 495                                         // Already in a toplevel window, so send a position
 496                                         SendPosition (toplevel, drag_data.Window,
 497                                                         drag_data.Action,
 498                                                         xevent.MotionEvent.x_root,
 499                                                         xevent.MotionEvent.y_root,
 500                                                         xevent.MotionEvent.time);
 501                                 }
 502
 503                                 drag_data.LastTopLevel = toplevel;
 504                                 drag_data.LastWindow = window;
 505                                 return true;
 506                         }
 507                         return false;
 508                 }
 509
 510                 // return true if the event is handled here
 511                 public bool HandleClientMessage (ref XEvent xevent)
 512                 {
 513                         // most common so we check it first
 514                         if (xevent.ClientMessageEvent.message_type == XdndPosition)
 515                                 return Accepting_HandlePositionEvent (ref xevent);
 516                         if (xevent.ClientMessageEvent.message_type == XdndEnter)
 517                                 return Accepting_HandleEnterEvent (ref xevent);
 518                         if (xevent.ClientMessageEvent.message_type == XdndDrop)
 519                                 return Accepting_HandleDropEvent (ref xevent);
 520                         if (xevent.ClientMessageEvent.message_type == XdndLeave)
 521                                 return Accepting_HandleLeaveEvent (ref xevent);
 522                         if (xevent.ClientMessageEvent.message_type == XdndStatus)
 523                                 return HandleStatusEvent (ref xevent);
 524
 525                         return false;
 526                 }
 527
 528                 public bool HandleSelectionNotifyEvent (ref XEvent xevent)
 529                 {
 530                         if (source != XplatUIX11.XGetSelectionOwner (display, XdndSelection))
 531                                 return false;
 532
 533                         MimeHandler handler = FindHandler ((IntPtr) xevent.SelectionEvent.target);
 534                         if (handler == null)
 535                                 return false;
 536                         if (data == null)
 537                                 data = new DataObject ();
 538
 539                         handler.Converter.GetData (this, data, ref xevent);
 540
 541                         converts_pending--;
 542                         if (converts_pending <= 0 && position_recieved) {
 543                                 drag_event = new DragEventArgs (data, 0, pos_x, pos_y,
 544                                         allowed, DragDropEffects.None);
 545                                 control.DndEnter (drag_event);
 546                                 SendStatus (source, drag_event.Effect);
 547                                 status_sent = true;
 548                         }
 549                         return true;
 550                 }
 551
 552                 public bool HandleSelectionRequestEvent (ref XEvent xevent)
 553                 {
 554                         if (xevent.SelectionRequestEvent.selection != XdndSelection)
 555                                 return false;
 556
 557                         MimeHandler handler = FindHandler (xevent.SelectionRequestEvent.target);
 558                         if (handler == null)
 559                                 return false;
 560
 561                         handler.Converter.SetData (this, drag_data.Data, ref xevent);
 562
 563                         return true;
 564                 }
 565
 566                 private void SetProperty (ref XEvent xevent, IntPtr data, int length)
 567                 {
 568                         XEvent sel = new XEvent();
 569                         sel.SelectionEvent.type = XEventName.SelectionNotify;
 570                         sel.SelectionEvent.send_event = true;
 571                         sel.SelectionEvent.display = display;
 572                         sel.SelectionEvent.selection = xevent.SelectionRequestEvent.selection;
 573                         sel.SelectionEvent.target = xevent.SelectionRequestEvent.target;
 574                         sel.SelectionEvent.requestor = xevent.SelectionRequestEvent.requestor;
 575                         sel.SelectionEvent.time = xevent.SelectionRequestEvent.time;
 576                         sel.SelectionEvent.property = IntPtr.Zero;
 577
 578                         XplatUIX11.XChangeProperty (display, xevent.SelectionRequestEvent.requestor,
 579                                         xevent.SelectionRequestEvent.property,
 580                                         xevent.SelectionRequestEvent.target,
 581                                         8, PropertyMode.Replace, data, length);
 582                         sel.SelectionEvent.property = xevent.SelectionRequestEvent.property;
 583
 584                         XplatUIX11.XSendEvent (display, xevent.SelectionRequestEvent.requestor, false,
 585                                         (IntPtr)EventMask.NoEventMask, ref sel);
 586                         return;
 587                 }
 588
 589                 private void Reset ()
 590                 {
 591                         ResetSourceData ();
 592                         ResetTargetData ();
 593                 }
 594
 595                 private void ResetSourceData ()
 596                 {
 597                         converts_pending = 0;
 598                         data = null;
 599                 }
 600
 601                 private void ResetTargetData ()
 602                 {
 603                         position_recieved = false;
 604                         status_sent = false;
 605                 }
 606
 607                 private bool Accepting_HandleEnterEvent (ref XEvent xevent)
 608                 {
 609                         Reset ();
 610
 611                         source = xevent.ClientMessageEvent.ptr1;
 612                         toplevel = xevent.AnyEvent.window;
 613                         target = IntPtr.Zero;
 614
 615                         ConvertData (ref xevent);
 616
 617                         return true;
 618                 }
 619
 620                 private bool Accepting_HandlePositionEvent (ref XEvent xevent)
 621                 {
 622                         pos_x = (int) xevent.ClientMessageEvent.ptr3 >> 16;
 623                         pos_y = (int) xevent.ClientMessageEvent.ptr3 & 0xFFFF;
 624
 625                         // Copy is implicitly allowed
 626                         allowed = EffectFromAction (xevent.ClientMessageEvent.ptr5) | DragDropEffects.Copy;
 627
 628                         IntPtr parent, child, new_child, last_drop_child;
 629                         parent = XplatUIX11.XRootWindow (display, 0);
 630                         child = toplevel;
 631                         last_drop_child = IntPtr.Zero;
 632                         while (true) {
 633                                 int xd, yd;
 634                                 new_child = IntPtr.Zero;
 635
 636                                 if (!XplatUIX11.XTranslateCoordinates (display,
 637                                                     parent, child, pos_x, pos_y,
 638                                                     out xd, out yd, out new_child))
 639                                         break;
 640                                 if (new_child == IntPtr.Zero)
 641                                         break;
 642                                 child = new_child;
 643
 644                                 Hwnd h = Hwnd.ObjectFromHandle (child);
 645                                 Control d = Control.FromHandle (h.client_window);
 646                                 if (d != null && d.allow_drop)
 647                                         last_drop_child = child;
 648                         }
 649
 650                         if (last_drop_child != IntPtr.Zero)
 651                                 child = last_drop_child;
 652
 653                         if (target != child) {
 654                                 // We have moved into a new control
 655                                 // or into a control for the first time
 656                                 Finish ();
 657                         }
 658                         target = child;
 659                         Hwnd hwnd = Hwnd.ObjectFromHandle (target);
 660                         Control c = Control.FromHandle (hwnd.client_window);
 661
 662                         if (c == null)
 663                                 return true;
 664                         if (!c.allow_drop) {
 665                                 SendStatus (source, DragDropEffects.None);
 666                                 Finish ();
 667                                 return true;
 668                         }
 669
 670                         control = c;
 671                         position_recieved = true;
 672
 673                         if (converts_pending > 0)
 674                                 return true;
 675                         if (!status_sent) {
 676                                 drag_event = new DragEventArgs (data, 0, pos_x, pos_y,
 677                                         allowed, DragDropEffects.None);
 678                                 control.DndEnter (drag_event);
 679                                 SendStatus (source, drag_event.Effect);
 680                                 status_sent = true;
 681                         } else {
 682                                 drag_event.x = pos_x;
 683                                 drag_event.y = pos_y;
 684                                 control.DndOver (drag_event);
 685                                 SendStatus (source, drag_event.Effect);
 686                         }
 687
 688                         return true;
 689                 }
 690
 691                 private void Finish ()
 692                 {
 693                         if (control != null) {
 694                                 if (drag_event == null) {
 695                                         if (data == null)
 696                                                 data = new DataObject ();
 697                                         drag_event = new DragEventArgs (data,
 698                                                         0, pos_x, pos_y,
 699                                         allowed, DragDropEffects.None);
 700                                 }
 701                                 control.DndLeave (drag_event);
 702                         }
 703                         ResetTargetData ();
 704                 }
 705
 706                 private bool Accepting_HandleDropEvent (ref XEvent xevent)
 707                 {
 708                         if (control != null && drag_event != null) {
 709                                 drag_event = new DragEventArgs (data,
 710                                                 0, pos_x, pos_y,
 711                                         allowed, DragDropEffects.None);
 712                                 control.DndDrop (drag_event);
 713                         }
 714                         SendFinished ();
 715                         return true;
 716                 }
 717
 718                 private bool Accepting_HandleLeaveEvent (ref XEvent xevent)
 719                 {
 720                         if (control != null && drag_event != null)
 721                                 control.DndLeave (drag_event);
 722                         // Reset ();
 723                         return true;
 724                 }
 725
 726                 private bool HandleStatusEvent (ref XEvent xevent)
 727                 {
 728                         if (drag_data != null && drag_data.State == DragState.Entered) {
 729                                 drag_data.WillAccept = ((int) xevent.ClientMessageEvent.ptr2 & 0x1) != 0;
 730                                 Cursor cursor = CursorNo;
 731                                 if (drag_data.WillAccept) {
 732                                         // Same order as on MS
 733                                         IntPtr action = xevent.ClientMessageEvent.ptr5;
 734                                         if (action == XdndActionCopy)
 735                                                 cursor = CursorCopy;
 736                                         else if (action == XdndActionLink)
 737                                                 cursor = CursorLink;
 738                                         else if (action == XdndActionMove)
 739                                                 cursor = CursorMove;
 740
 741                                 }
 742
 743                                         // TODO: Try not to set the cursor so much
 744                                 //if (cursor.Handle != CurrentCursorHandle) {
 745                                         XplatUIX11.XChangeActivePointerGrab (display,
 746                                                         EventMask.ButtonMotionMask |
 747                                                         EventMask.PointerMotionMask |
 748                                                         EventMask.ButtonPressMask |
 749                                                         EventMask.ButtonReleaseMask,
 750                                                         cursor.Handle, IntPtr.Zero);
 751                                         //CurrentCursorHandle = cursor.Handle;
 752                                         //}
 753                         }
 754                         return true;
 755                 }
 756
 757                 private DragDropEffects EffectFromAction (IntPtr action)
 758                 {
 759                         DragDropEffects allowed = DragDropEffects.None;
 760
 761                         if (action == XdndActionCopy)
 762                                 allowed = DragDropEffects.Copy;
 763                         else if (action == XdndActionMove)
 764                                 allowed |= DragDropEffects.Move;
 765                         if (action == XdndActionLink)
 766                                 allowed |= DragDropEffects.Link;
 767                         return allowed;
 768                 }
 769
 770                 private IntPtr ActionFromEffect (DragDropEffects effect)
 771                 {
 772                         IntPtr action = IntPtr.Zero;
 773
 774                         // We can't OR together actions on XDND so sadly the primary
 775                         // is the only one shown here
 776                         if ((effect & DragDropEffects.Copy) != 0)
 777                                 action = XdndActionCopy;
 778                         else if ((effect & DragDropEffects.Move) != 0)
 779                                 action = XdndActionMove;
 780                         else if ((effect & DragDropEffects.Link) != 0)
 781                                 action = XdndActionLink;
 782                         return action;
 783                 }
 784
 785                 private bool ConvertData (ref XEvent xevent)
 786                 {
 787                         bool match = false;
 788
 789                         if (source != XplatUIX11.XGetSelectionOwner (display, XdndSelection)) {
 790                                 return false;
 791                         }
 792
 793                         Control mwfcontrol = MwfWindow (source);
 794
 795                         if (mwfcontrol != null && drag_data != null) {
 796                                 DataObject dragged = drag_data.Data as DataObject;
 797                                 if (dragged != null) {
 798                                         data = dragged;
 799                                 } else {
 800                                         if (data == null)
 801                                                 data = new DataObject ();
 802                                         SetDataWithFormats (drag_data.Data);
 803                                 }
 804                                 return true;
 805                         }
 806
 807                         foreach (IntPtr atom in SourceSupportedList (ref xevent)) {
 808                                 MimeHandler handler = FindHandler (atom);
 809                                 if (handler == null)
 810                                         continue;
 811                                 XplatUIX11.XConvertSelection (display, XdndSelection, handler.Type,
 812                                         handler.NonProtocol, toplevel, IntPtr.Zero /* CurrentTime */);
 813                                 converts_pending++;
 814                                 match = true;
 815                         }
 816                         return match;
 817                 }
 818
 819                 private void SetDataWithFormats (object value)
 820                 {
 821                         if (value is string) {
 822                                 data.SetData (DataFormats.Text, value);
 823                                 data.SetData (DataFormats.UnicodeText, value);
 824                         }
 825
 826                         data.SetData (value);
 827                 }
 828
 829                 private MimeHandler FindHandler (IntPtr atom)
 830                 {
 831                         if (atom == IntPtr.Zero)
 832                                 return null;
 833                         foreach (MimeHandler handler in MimeHandlers) {
 834                                 if (handler.Type == atom)
 835                                         return handler;
 836                         }
 837                         return null;
 838                 }
 839
 840                 private MimeHandler FindHandler (string name)
 841                 {
 842                         foreach (MimeHandler handler in MimeHandlers) {
 843                                 if (handler.Name == name)
 844                                         return handler;
 845                         }
 846                         return null;
 847                 }
 848
 849                 private void SendStatus (IntPtr source, DragDropEffects effect)
 850                 {
 851                         XEvent xevent = new XEvent ();
 852
 853                         xevent.AnyEvent.type = XEventName.ClientMessage;
 854                         xevent.AnyEvent.display = display;
 855                         xevent.ClientMessageEvent.window = source;
 856                         xevent.ClientMessageEvent.message_type = XdndStatus;
 857                         xevent.ClientMessageEvent.format = 32;
 858                         xevent.ClientMessageEvent.ptr1 = toplevel;
 859                         if (effect != DragDropEffects.None)
 860                                 xevent.ClientMessageEvent.ptr2 = (IntPtr) 1;
 861
 862                         xevent.ClientMessageEvent.ptr5 = ActionFromEffect (effect);
 863                         XplatUIX11.XSendEvent (display, source, false, IntPtr.Zero, ref xevent);
 864                 }
 865
 866                 private void SendEnter (IntPtr handle, IntPtr from, IntPtr [] supported)
 867                 {
 868                         XEvent xevent = new XEvent ();
 869
 870                         xevent.AnyEvent.type = XEventName.ClientMessage;
 871                         xevent.AnyEvent.display = display;
 872                         xevent.ClientMessageEvent.window = handle;
 873                         xevent.ClientMessageEvent.message_type = XdndEnter;
 874                         xevent.ClientMessageEvent.format = 32;
 875                         xevent.ClientMessageEvent.ptr1 = from;
 876
 877                         // (int) xevent.ClientMessageEvent.ptr2 & 0x1)
 878                         // int ptr2 = 0x1;
 879                         // xevent.ClientMessageEvent.ptr2 = (IntPtr) ptr2;
 880                         // (e)->xclient.data.l[1] = ((e)->xclient.data.l[1] & ~(0xFF << 24)) | ((v) << 24)
 881                         xevent.ClientMessageEvent.ptr2 = (IntPtr) ((long)XdndVersion [0] << 24);
 882
 883                         if (supported.Length > 0)
 884                                 xevent.ClientMessageEvent.ptr3 = supported [0];
 885                         if (supported.Length > 1)
 886                                 xevent.ClientMessageEvent.ptr4 = supported [1];
 887                         if (supported.Length > 2)
 888                                 xevent.ClientMessageEvent.ptr5 = supported [2];
 889
 890                         XplatUIX11.XSendEvent (display, handle, false, IntPtr.Zero, ref xevent);
 891                 }
 892
 893                 private void SendDrop (IntPtr handle, IntPtr from, IntPtr time)
 894                 {
 895                         XEvent xevent = new XEvent ();
 896
 897                         xevent.AnyEvent.type = XEventName.ClientMessage;
 898                         xevent.AnyEvent.display = display;
 899                         xevent.ClientMessageEvent.window = handle;
 900                         xevent.ClientMessageEvent.message_type = XdndDrop;
 901                         xevent.ClientMessageEvent.format = 32;
 902                         xevent.ClientMessageEvent.ptr1 = from;
 903                         xevent.ClientMessageEvent.ptr3 = time;
 904
 905                         XplatUIX11.XSendEvent (display, handle, false, IntPtr.Zero, ref xevent);
 906                 }
 907
 908                 private void SendPosition (IntPtr handle, IntPtr from, IntPtr action, int x, int y, IntPtr time)
 909                 {
 910                         XEvent xevent = new XEvent ();
 911
 912                         xevent.AnyEvent.type = XEventName.ClientMessage;
 913                         xevent.AnyEvent.display = display;
 914                         xevent.ClientMessageEvent.window = handle;
 915                         xevent.ClientMessageEvent.message_type = XdndPosition;
 916                         xevent.ClientMessageEvent.format = 32;
 917                         xevent.ClientMessageEvent.ptr1 = from;
 918                         xevent.ClientMessageEvent.ptr3 = (IntPtr) ((x << 16) | (y & 0xFFFF));
 919                         xevent.ClientMessageEvent.ptr4 = time;
 920                         xevent.ClientMessageEvent.ptr5 = action;
 921
 922                         XplatUIX11.XSendEvent (display, handle, false, IntPtr.Zero, ref xevent);
 923                 }
 924
 925                 private void SendLeave (IntPtr handle, IntPtr from)
 926                 {
 927                         XEvent xevent = new XEvent ();
 928
 929                         xevent.AnyEvent.type = XEventName.ClientMessage;
 930                         xevent.AnyEvent.display = display;
 931                         xevent.ClientMessageEvent.window = handle;
 932                         xevent.ClientMessageEvent.message_type = XdndLeave;
 933                         xevent.ClientMessageEvent.format = 32;
 934                         xevent.ClientMessageEvent.ptr1 = from;
 935
 936                         XplatUIX11.XSendEvent (display, handle, false, IntPtr.Zero, ref xevent);
 937                 }
 938
 939                 private void SendFinished ()
 940                 {
 941                         XEvent xevent = new XEvent ();
 942
 943                         xevent.AnyEvent.type = XEventName.ClientMessage;
 944                         xevent.AnyEvent.display = display;
 945                         xevent.ClientMessageEvent.window = source;
 946                         xevent.ClientMessageEvent.message_type = XdndFinished;
 947                         xevent.ClientMessageEvent.format = 32;
 948                         xevent.ClientMessageEvent.ptr1 = toplevel;
 949
 950                         XplatUIX11.XSendEvent (display, source, false, IntPtr.Zero, ref xevent);
 951                 }
 952
 953                 // There is a somewhat decent amount of overhead
 954                 // involved in setting up dnd so we do it lazily
 955                 // as a lot of applications do not even use it.
 956                 private void Init ()
 957                 {
 958                         XdndAware = XplatUIX11.XInternAtom (display, "XdndAware", false);
 959                         XdndEnter = XplatUIX11.XInternAtom (display, "XdndEnter", false);
 960                         XdndLeave = XplatUIX11.XInternAtom (display, "XdndLeave", false);
 961                         XdndPosition = XplatUIX11.XInternAtom (display, "XdndPosition", false);
 962                         XdndStatus = XplatUIX11.XInternAtom (display, "XdndStatus", false);
 963                         XdndDrop = XplatUIX11.XInternAtom (display, "XdndDrop", false);
 964                         XdndSelection = XplatUIX11.XInternAtom (display, "XdndSelection", false);
 965                         XdndFinished = XplatUIX11.XInternAtom (display, "XdndFinished", false);
 966                         XdndTypeList = XplatUIX11.XInternAtom (display, "XdndTypeList", false);
 967                         XdndActionCopy = XplatUIX11.XInternAtom (display, "XdndActionCopy", false);
 968                         XdndActionMove = XplatUIX11.XInternAtom (display, "XdndActionMove", false);
 969                         XdndActionLink = XplatUIX11.XInternAtom (display, "XdndActionLink", false);
 970                         //XdndActionPrivate = XplatUIX11.XInternAtom (display, "XdndActionPrivate", false);
 971                         //XdndActionList = XplatUIX11.XInternAtom (display, "XdndActionList", false);
 972                         //XdndActionDescription = XplatUIX11.XInternAtom (display, "XdndActionDescription", false);
 973                         //XdndActionAsk = XplatUIX11.XInternAtom (display, "XdndActionAsk", false);
 974
 975                         foreach (MimeHandler handler in MimeHandlers) {
 976                                 handler.Type = XplatUIX11.XInternAtom (display, handler.Name, false);
 977                                 handler.NonProtocol = XplatUIX11.XInternAtom (display,
 978                                                 String.Concat ("MWFNonP+", handler.Name), false);
 979                         }
 980
 981                 }
 982
 983                 private IntPtr [] SourceSupportedList (ref XEvent xevent)
 984                 {
 985                         IntPtr [] res;
 986
 987
 988                         if (((int) xevent.ClientMessageEvent.ptr2 & 0x1) == 0) {
 989                                 res = new IntPtr [3];
 990                                 res [0] = xevent.ClientMessageEvent.ptr3;
 991                                 res [1] = xevent.ClientMessageEvent.ptr4;
 992                                 res [2] = xevent.ClientMessageEvent.ptr5;
 993                         } else {
 994                                 IntPtr type;
 995                                 int format;
 996                                 IntPtr count;
 997                                 IntPtr remaining;
 998                                 IntPtr data = IntPtr.Zero;
 999
1000                                 XplatUIX11.XGetWindowProperty (display, source, XdndTypeList,
1001                                                 IntPtr.Zero, new IntPtr(32), false, (IntPtr) Atom.XA_ATOM,
1002                                                 out type, out format, out count,
1003                                                 out remaining, ref data);
1004
1005                                 res = new IntPtr [count.ToInt32()];
1006                                 for (int i = 0; i < count.ToInt32(); i++) {
1007                                         res [i] = (IntPtr) Marshal.ReadInt32 (data, i *
1008                                                         Marshal.SizeOf (typeof (int)));
1009                                 }
1010
1011                                 XplatUIX11.XFree (data);
1012                         }
1013
1014                         return res;
1015                 }
1016
1017                 private string GetText (ref XEvent xevent, bool unicode)
1018                 {
1019                         int nread = 0;
1020                         IntPtr nitems;
1021                         IntPtr bytes_after;
1022
1023                         StringBuilder builder = new StringBuilder ();
1024                         do {
1025                                 IntPtr actual_type;
1026                                 int actual_fmt;
1027                                 IntPtr data = IntPtr.Zero;
1028
1029                                 if (0 != XplatUIX11.XGetWindowProperty (display,
1030                                                     xevent.AnyEvent.window,
1031                                                     (IntPtr) xevent.SelectionEvent.property,
1032                                                     IntPtr.Zero, new IntPtr(0xffffff), false,
1033                                                     (IntPtr) Atom.AnyPropertyType, out actual_type,
1034                                                     out actual_fmt, out nitems, out bytes_after,
1035                                                     ref data)) {
1036                                         XplatUIX11.XFree (data);
1037                                         break;
1038                                 }
1039
1040                                 if (unicode)
1041                                         builder.Append (Marshal.PtrToStringUni (data));
1042                                 else
1043                                         builder.Append (Marshal.PtrToStringAnsi (data));
1044                                 nread += nitems.ToInt32();
1045
1046                                 XplatUIX11.XFree (data);
1047                         } while (bytes_after.ToInt32() > 0);
1048                         if (nread == 0)
1049                                 return null;
1050                         return builder.ToString ();
1051                 }
1052
1053                 private MemoryStream GetData (ref XEvent xevent)
1054                 {
1055                         int nread = 0;
1056                         IntPtr nitems;
1057                         IntPtr bytes_after;
1058
1059                         MemoryStream res = new MemoryStream ();
1060                         do {
1061                                 IntPtr actual_type;
1062                                 int actual_fmt;
1063                                 IntPtr data = IntPtr.Zero;
1064
1065                                 if (0 != XplatUIX11.XGetWindowProperty (display,
1066                                                     xevent.AnyEvent.window,
1067                                                     (IntPtr) xevent.SelectionEvent.property,
1068                                                     IntPtr.Zero, new IntPtr(0xffffff), false,
1069                                                     (IntPtr) Atom.AnyPropertyType, out actual_type,
1070                                                     out actual_fmt, out nitems, out bytes_after,
1071                                                     ref data)) {
1072                                         XplatUIX11.XFree (data);
1073                                         break;
1074                                 }
1075
1076                                 for (int i = 0; i < nitems.ToInt32(); i++)
1077                                         res.WriteByte (Marshal.ReadByte (data, i));
1078                                 nread += nitems.ToInt32();
1079
1080                                 XplatUIX11.XFree (data);
1081                         } while (bytes_after.ToInt32() > 0);
1082                         return res;
1083                 }
1084
1085                 private Control MwfWindow (IntPtr window)
1086                 {
1087                         Hwnd hwnd = Hwnd.ObjectFromHandle (window);
1088                         if (hwnd == null)
1089                                 return null;
1090
1091                         Control res = Control.FromHandle (hwnd.client_window);
1092                         return res;
1093                 }
1094
1095                 private bool IsWindowDndAware (IntPtr handle)
1096                 {
1097                         bool res = true;
1098                         // Check the version number, we need greater than 3
1099                         IntPtr actual;
1100                         int format;
1101                         IntPtr count;
1102                         IntPtr remaining;
1103                         IntPtr data = IntPtr.Zero;
1104
1105                         XplatUIX11.XGetWindowProperty (display, handle, XdndAware, IntPtr.Zero, new IntPtr(0x8000000), false,
1106                                         (IntPtr) Atom.XA_ATOM, out actual, out format,
1107                                         out count, out remaining, ref data);
1108
1109                         if (actual != (IntPtr) Atom.XA_ATOM || format != 32 ||
1110                                         count.ToInt32() == 0 || data == IntPtr.Zero) {
1111                                 if (data != IntPtr.Zero)
1112                                         XplatUIX11.XFree (data);
1113                                 return false;
1114                         }
1115
1116                         int version = Marshal.ReadInt32 (data, 0);
1117
1118                         if (version < 3) {
1119                                 Console.Error.WriteLine ("XDND Version too old (" + version + ").");
1120                                 XplatUIX11.XFree (data);
1121                                 return false;
1122                         }
1123
1124                         // First type is actually the XDND version
1125                         if (count.ToInt32() > 1) {
1126                                 res = false;
1127                                 for (int i = 1; i < count.ToInt32(); i++) {
1128                                         IntPtr type = (IntPtr) Marshal.ReadInt32 (data, i *
1129                                                         Marshal.SizeOf (typeof (int)));
1130                                         for (int j = 0; j < drag_data.SupportedTypes.Length; j++) {
1131                                                 if (drag_data.SupportedTypes [j] == type) {
1132                                                         res = true;
1133                                                         break;
1134                                                 }
1135                                         }
1136                                 }
1137                         }
1138
1139                         XplatUIX11.XFree (data);
1140                         return res;
1141                 }
1142
1143                 private IntPtr [] DetermineSupportedTypes (object data)
1144                 {
1145                         ArrayList res = new ArrayList ();
1146
1147                         if (data is string) {
1148                                 MimeHandler handler = FindHandler ("text/plain");
1149                                 if (handler != null)
1150                                         res.Add (handler.Type);
1151                         }/* else if (data is Bitmap)
1152                                 res.Add (data);
1153
1154                          */
1155
1156                         if (data is IDataObject) {
1157
1158
1159                         }
1160
1161                         if (data is ISerializable) {
1162                                 MimeHandler handler = FindHandler ("application/x-mono-serialized-object");
1163                                 if (handler != null)
1164                                         res.Add (handler.Type);
1165                         }
1166
1167                         return (IntPtr []) res.ToArray (typeof (IntPtr));
1168                 }
1169         }
1170 }