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 == (int) 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 == (int) 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 uint [] XdndVersion = new uint [] { 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 IntPtr drag_action;
 318                 private Control control;
 319                 private int pos_x, pos_y;
 320                 private DragDropEffects allowed;
 321                 private DragEventArgs drag_event;
 322
 323                 private Cursor CursorNo;
 324                 private Cursor CursorCopy;
 325                 private Cursor CursorMove;
 326                 private Cursor CursorLink;
 327                 private IntPtr CurrentCursorHandle;
 328
 329                 public X11Dnd (IntPtr display)
 330                 {
 331                         this.display = display;
 332                         Init ();
 333                 }
 334
 335                 public void SetAllowDrop (Hwnd hwnd, bool allow)
 336                 {
 337                         if (hwnd.allow_drop == allow)
 338                                 return;
 339
 340                         XChangeProperty (display, hwnd.whole_window, XdndAware,
 341                                         (IntPtr) Atom.XA_ATOM, 32,
 342                                         PropertyMode.Replace, XdndVersion, allow ? 1 : 0);
 343                         hwnd.allow_drop = allow;
 344                 }
 345
 346                 public DragDropEffects StartDrag (IntPtr handle, object data,
 347                                 DragDropEffects allowed_effects)
 348                 {
 349                         drag_data = new DragData ();
 350                         drag_data.Window = handle;
 351                         drag_data.State = DragState.Beginning;
 352                         drag_data.MouseState = XplatUIX11.MouseState;
 353                         drag_data.Data = data;
 354                         drag_data.SupportedTypes = DetermineSupportedTypes (data);
 355
 356                         drag_data.Action = ActionFromEffect (allowed_effects);
 357
 358                         if (CursorNo == null) {
 359                                 // Make sure the cursors are created
 360                                 CursorNo = new Cursor (typeof (X11Dnd), "DnDNo.cur");
 361                                 CursorCopy = new Cursor (typeof (X11Dnd), "DnDCopy.cur");
 362                                 CursorMove = new Cursor (typeof (X11Dnd), "DnDMove.cur");
 363                                 CursorLink = new Cursor (typeof (X11Dnd), "DnDLink.cur");
 364                         }
 365
 366                         drag_data.LastTopLevel = IntPtr.Zero;
 367                         return DragDropEffects.Copy;
 368                 }
 369
 370                 public void HandleButtonRelease (ref XEvent xevent)
 371                 {
 372                         if (drag_data == null)
 373                                 return;
 374
 375                         if (!((drag_data.MouseState == MouseButtons.Left &&
 376                                               xevent.ButtonEvent.button == 1) ||
 377                                             (drag_data.MouseState == MouseButtons.Right &&
 378                                                             xevent.ButtonEvent.button == 3)))
 379                                 return;
 380
 381                         if (drag_data.State == DragState.Beginning) {
 382                                 state = State.Accepting;
 383                         } else if (drag_data.State != DragState.None) {
 384
 385                                 if (drag_data.WillAccept) {
 386                                         SendDrop (drag_data.LastTopLevel, xevent.AnyEvent.window,
 387                                                         xevent.ButtonEvent.time);
 388                                 }
 389
 390                                 XplatUIX11.XUngrabPointer (display, 0);
 391                                 drag_data.State = DragState.None;
 392                                 // WE can't reset the drag data yet as it is still
 393                                 // most likely going to be used by the SelectionRequest
 394                                 // handlers
 395                         }
 396                 }
 397
 398                 public bool HandleMotionNotify (ref XEvent xevent)
 399                 {
 400                         if (drag_data == null)
 401                                 return false;
 402
 403                         if (drag_data.State == DragState.Beginning) {
 404                                 int suc;
 405
 406                                 drag_data.State = DragState.Dragging;
 407
 408                                 suc = XplatUIX11.XSetSelectionOwner (display, (int) XdndSelection,
 409                                                 drag_data.Window,
 410                                                 xevent.ButtonEvent.time);
 411
 412                                 if (suc == 0) {
 413                                         Console.Error.WriteLine ("Could not take ownership of XdndSelection aborting drag.");
 414                                         drag_data.Reset ();
 415                                         return false;
 416                                 }
 417
 418                                 suc = XGrabPointer (display, xevent.AnyEvent.window,
 419                                                 false,
 420                                                 EventMask.ButtonMotionMask |
 421                                                 EventMask.PointerMotionMask |
 422                                                 EventMask.ButtonPressMask |
 423                                                 EventMask.ButtonReleaseMask,
 424                                                 GrabMode.GrabModeAsync,
 425                                                 GrabMode.GrabModeAsync,
 426                                                 IntPtr.Zero, IntPtr.Zero/*CursorCopy.Handle*/, 0);
 427
 428                                 if (suc != 0) {
 429                                         Console.Error.WriteLine ("Could not grab pointer aborting drag.");
 430                                         drag_data.Reset ();
 431                                         return false;
 432                                 }
 433
 434                                 drag_data.State = DragState.Dragging;
 435                         } else if (drag_data.State != DragState.None) {
 436                                 bool dnd_aware = false;
 437                                 IntPtr toplevel = IntPtr.Zero;
 438                                 IntPtr window = XplatUIX11.RootWindowHandle;
 439
 440                                 IntPtr root, child;
 441                                 int x_temp, y_temp;
 442                                 int mask_return;
 443
 444                                 while (XQueryPointer (display,
 445                                                        window,
 446                                                        out root, out child,
 447                                                        out x_temp, out y_temp,
 448                                                        out xevent.MotionEvent.x,
 449                                                        out xevent.MotionEvent.y,
 450                                                        out mask_return)) {
 451
 452                                         if (!dnd_aware) {
 453                                                 dnd_aware = IsWindowDndAware (window);
 454                                                 if (dnd_aware) {
 455                                                         toplevel = window;
 456                                                         xevent.MotionEvent.x_root = x_temp;
 457                                                         xevent.MotionEvent.y_root = y_temp;
 458                                                 }
 459                                         }
 460
 461                                         if (child == IntPtr.Zero)
 462                                                 break;
 463
 464                                         window = child;
 465                                 }
 466
 467                                 if (window != drag_data.LastWindow && drag_data.State == DragState.Entered) {
 468                                         drag_data.State = DragState.Dragging;
 469
 470                                         // TODO: Send a Leave if this is an MWF window
 471
 472                                         if (toplevel != drag_data.LastTopLevel)
 473                                                 SendLeave (drag_data.LastTopLevel, xevent.MotionEvent.window);
 474                                 }
 475
 476                                 drag_data.State = DragState.Entered;
 477                                 if (toplevel != drag_data.LastTopLevel) {
 478                                         // Entering a new toplevel window
 479                                         SendEnter (toplevel, drag_data.Window, drag_data.SupportedTypes);
 480                                 } else {
 481                                         // Already in a toplevel window, so send a position
 482                                         SendPosition (toplevel, drag_data.Window,
 483                                                         drag_data.Action,
 484                                                         xevent.MotionEvent.x_root,
 485                                                         xevent.MotionEvent.y_root,
 486                                                         xevent.MotionEvent.time);
 487                                 }
 488
 489                                 drag_data.LastTopLevel = toplevel;
 490                                 drag_data.LastWindow = window;
 491                                 return true;
 492                         }
 493                         return false;
 494                 }
 495
 496                 // DEBUG CODE REMOVE
 497                 private string GetText (IntPtr handle) {
 498                         string text = String.Empty;
 499                         IntPtr  textptr;
 500
 501                         textptr = IntPtr.Zero;
 502
 503                         XFetchName (display, handle, ref textptr);
 504                         if (textptr != IntPtr.Zero) {
 505                                 text = Marshal.PtrToStringAnsi(textptr);
 506                                 XFree (textptr);
 507                         }
 508
 509                         return text;
 510                 }
 511
 512
 513                 // return true if the event is handled here
 514                 public bool HandleClientMessage (ref XEvent xevent)
 515                 {
 516                         // most common so we check it first
 517                         if (xevent.ClientMessageEvent.message_type == XdndPosition)
 518                                 return Accepting_HandlePositionEvent (ref xevent);
 519                         if (xevent.ClientMessageEvent.message_type == XdndEnter)
 520                                 return Accepting_HandleEnterEvent (ref xevent);
 521                         if (xevent.ClientMessageEvent.message_type == XdndDrop)
 522                                 return Accepting_HandleDropEvent (ref xevent);
 523                         if (xevent.ClientMessageEvent.message_type == XdndLeave)
 524                                 return Accepting_HandleLeaveEvent (ref xevent);
 525                         if (xevent.ClientMessageEvent.message_type == XdndStatus)
 526                                 return HandleStatusEvent (ref xevent);
 527
 528                         return false;
 529                 }
 530
 531                 public bool HandleSelectionNotifyEvent (ref XEvent xevent)
 532                 {
 533                         if (source != XGetSelectionOwner (display, XdndSelection))
 534                                 return false;
 535
 536                         MimeHandler handler = FindHandler ((IntPtr) xevent.SelectionEvent.target);
 537                         if (handler == null)
 538                                 return false;
 539                         if (data == null)
 540                                 data = new DataObject ();
 541
 542                         handler.Converter.GetData (this, data, ref xevent);
 543
 544                         converts_pending--;
 545                         if (converts_pending <= 0 && position_recieved) {
 546                                 drag_event = new DragEventArgs (data, 0, pos_x, pos_y,
 547                                         allowed, DragDropEffects.None);
 548                                 control.DndEnter (drag_event);
 549                                 SendStatus (source, drag_event.Effect);
 550                                 status_sent = true;
 551                         }
 552                         return true;
 553                 }
 554
 555                 public bool HandleSelectionRequestEvent (ref XEvent xevent)
 556                 {
 557                         if (xevent.SelectionRequestEvent.selection != (int) XdndSelection)
 558                                 return false;
 559
 560                         MimeHandler handler = FindHandler ((IntPtr) xevent.SelectionRequestEvent.target);
 561                         if (handler == null)
 562                                 return false;
 563
 564                         handler.Converter.SetData (this, drag_data.Data, ref xevent);
 565
 566                         return true;
 567                 }
 568
 569                 private void SetProperty (ref XEvent xevent, IntPtr data, int length)
 570                 {
 571                         XEvent sel = new XEvent();
 572                         sel.SelectionEvent.type = XEventName.SelectionNotify;
 573                         sel.SelectionEvent.send_event = true;
 574                         sel.SelectionEvent.display = display;
 575                         sel.SelectionEvent.selection = xevent.SelectionRequestEvent.selection;
 576                         sel.SelectionEvent.target = xevent.SelectionRequestEvent.target;
 577                         sel.SelectionEvent.requestor = xevent.SelectionRequestEvent.requestor;
 578                         sel.SelectionEvent.time = xevent.SelectionRequestEvent.time;
 579                         sel.SelectionEvent.property = 0;
 580
 581                         XplatUIX11.XChangeProperty (display, xevent.SelectionRequestEvent.requestor,
 582                                         xevent.SelectionRequestEvent.property,
 583                                         xevent.SelectionRequestEvent.target,
 584                                         8, PropertyMode.Replace, data, length);
 585                         sel.SelectionEvent.property = xevent.SelectionRequestEvent.property;
 586
 587                         XSendEvent (display, xevent.SelectionRequestEvent.requestor, false,
 588                                         EventMask.NoEventMask, ref sel);
 589                         return;
 590                 }
 591
 592                 private void Reset ()
 593                 {
 594                         ResetSourceData ();
 595                         ResetTargetData ();
 596                 }
 597
 598                 private void ResetSourceData ()
 599                 {
 600                         converts_pending = 0;
 601                         data = null;
 602                 }
 603
 604                 private void ResetTargetData ()
 605                 {
 606                         position_recieved = false;
 607                         status_sent = false;
 608                 }
 609
 610                 private bool Accepting_HandleEnterEvent (ref XEvent xevent)
 611                 {
 612                         Reset ();
 613
 614                         source = xevent.ClientMessageEvent.ptr1;
 615                         toplevel = xevent.AnyEvent.window;
 616                         target = IntPtr.Zero;
 617
 618                         ConvertData (ref xevent);
 619
 620                         return true;
 621                 }
 622
 623                 private bool Accepting_HandlePositionEvent (ref XEvent xevent)
 624                 {
 625                         int x = (int) xevent.ClientMessageEvent.ptr3 >> 16;
 626                         int y = (int) xevent.ClientMessageEvent.ptr3 & 0xFFFF;
 627
 628                         allowed = EffectFromAction (xevent.ClientMessageEvent.ptr5);
 629
 630                         IntPtr parent, child, new_child;
 631                         parent = XplatUIX11.XRootWindow (display, 0);
 632                         child = toplevel;
 633                         while (true) {
 634                                 int xd, yd;
 635                                 new_child = IntPtr.Zero;
 636
 637                                 if (!XplatUIX11.XTranslateCoordinates (display,
 638                                                     parent, child, x, y,
 639                                                     out xd, out yd, out new_child))
 640                                         break;
 641                                 if (new_child == IntPtr.Zero)
 642                                         break;
 643                                 child = new_child;
 644                         }
 645
 646                         if (target != child) {
 647                                 // We have moved into a new control
 648                                 // or into a control for the first time
 649                                 Finish ();
 650                         }
 651                         target = child;
 652                         Hwnd hwnd = Hwnd.ObjectFromHandle (target);
 653                         Control c = Control.FromHandle (hwnd.client_window);
 654
 655                         if (c == null)
 656                                 return true;
 657                         if (!c.allow_drop) {
 658                                 SendStatus (source, DragDropEffects.None);
 659                                 Finish ();
 660                                 return true;
 661                         }
 662
 663                         control = c;
 664                         position_recieved = true;
 665
 666                         if (converts_pending > 0)
 667                                 return true;
 668                         if (!status_sent) {
 669                                 drag_event = new DragEventArgs (data, 0, pos_x, pos_y,
 670                                         allowed, DragDropEffects.None);
 671                                 control.DndEnter (drag_event);
 672                                 SendStatus (source, drag_event.Effect);
 673                                 status_sent = true;
 674                         } else {
 675                                 SendStatus (source, drag_event.Effect);
 676                                 control.DndOver (drag_event);
 677                         }
 678
 679                         return true;
 680                 }
 681
 682                 private void Finish ()
 683                 {
 684                         if (control != null) {
 685                                 if (drag_event == null) {
 686                                         if (data == null)
 687                                                 data = new DataObject ();
 688                                         drag_event = new DragEventArgs (data,
 689                                                         0, pos_x, pos_y,
 690                                         allowed, DragDropEffects.None);
 691                                 }
 692                                 control.DndLeave (drag_event);
 693                         }
 694                         ResetTargetData ();
 695                 }
 696
 697                 private bool Accepting_HandleDropEvent (ref XEvent xevent)
 698                 {
 699                         if (control != null && drag_event != null) {
 700                                 drag_event = new DragEventArgs (data,
 701                                                 0, pos_x, pos_y,
 702                                         allowed, DragDropEffects.None);
 703                                 control.DndDrop (drag_event);
 704                         }
 705                         SendFinished ();
 706                         return true;
 707                 }
 708
 709                 private bool Accepting_HandleLeaveEvent (ref XEvent xevent)
 710                 {
 711                         if (control != null && drag_event != null)
 712                                 control.DndLeave (drag_event);
 713                         // Reset ();
 714                         return true;
 715                 }
 716
 717                 private bool HandleStatusEvent (ref XEvent xevent)
 718                 {
 719                         if (drag_data != null && drag_data.State == DragState.Entered) {
 720                                 drag_data.WillAccept = ((int) xevent.ClientMessageEvent.ptr2 & 0x1) != 0;
 721                                 Cursor cursor = CursorNo;
 722                                 if (drag_data.WillAccept) {
 723                                         // Same order as on MS
 724                                         IntPtr action = xevent.ClientMessageEvent.ptr5;
 725                                         if (action == XdndActionCopy)
 726                                                 cursor = CursorCopy;
 727                                         else if (action == XdndActionLink)
 728                                                 cursor = CursorLink;
 729                                         else if (action == XdndActionMove)
 730                                                 cursor = CursorMove;
 731
 732                                 }
 733
 734                                         // TODO: Try not to set the cursor so much
 735                                 //if (cursor.Handle != CurrentCursorHandle) {
 736                                         XChangeActivePointerGrab (display,
 737                                                         EventMask.ButtonMotionMask |
 738                                                         EventMask.PointerMotionMask |
 739                                                         EventMask.ButtonPressMask |
 740                                                         EventMask.ButtonReleaseMask,
 741                                                         cursor.Handle, IntPtr.Zero);
 742                                         CurrentCursorHandle = cursor.Handle;
 743                                         //}
 744                         }
 745                         return true;
 746                 }
 747
 748                 private DragDropEffects EffectFromAction (IntPtr action)
 749                 {
 750                         DragDropEffects allowed = DragDropEffects.None;
 751
 752                         if (action == XdndActionCopy)
 753                                 allowed = DragDropEffects.Copy;
 754                         else if (action == XdndActionMove)
 755                                 allowed |= DragDropEffects.Move;
 756                         if (action == XdndActionLink)
 757                                 allowed |= DragDropEffects.Link;
 758                         return allowed;
 759                 }
 760
 761                 private IntPtr ActionFromEffect (DragDropEffects effect)
 762                 {
 763                         IntPtr action = IntPtr.Zero;
 764
 765                         // We can't OR together actions on XDND so sadly the primary
 766                         // is the only one shown here
 767                         if ((effect & DragDropEffects.Copy) != 0)
 768                                 action = XdndActionCopy;
 769                         else if ((effect & DragDropEffects.Move) != 0)
 770                                 action = XdndActionMove;
 771                         else if ((effect & DragDropEffects.Link) != 0)
 772                                 action = XdndActionLink;
 773                         return action;
 774                 }
 775
 776                 private bool ConvertData (ref XEvent xevent)
 777                 {
 778                         bool match = false;
 779
 780                         XplatUIX11.XGetSelectionOwner (display, (int) XdndSelection);
 781
 782                         foreach (IntPtr atom in SourceSupportedList (ref xevent)) {
 783                                 MimeHandler handler = FindHandler (atom);
 784                                 if (handler == null)
 785                                         continue;
 786                                 XConvertSelection (display, XdndSelection, handler.Type,
 787                                         handler.NonProtocol, toplevel, 0 /* CurrentTime */);
 788                                 converts_pending++;
 789                                 match = true;
 790                         }
 791                         return match;
 792                 }
 793
 794                 private MimeHandler FindHandler (IntPtr atom)
 795                 {
 796                         if (atom == IntPtr.Zero)
 797                                 return null;
 798                         foreach (MimeHandler handler in MimeHandlers) {
 799                                 if (handler.Type == atom)
 800                                         return handler;
 801                         }
 802                         return null;
 803                 }
 804
 805                 private MimeHandler FindHandler (string name)
 806                 {
 807                         foreach (MimeHandler handler in MimeHandlers) {
 808                                 if (handler.Name == name)
 809                                         return handler;
 810                         }
 811                         return null;
 812                 }
 813
 814                 private void SendStatus (IntPtr source, DragDropEffects effect)
 815                 {
 816                         XEvent xevent = new XEvent ();
 817
 818                         xevent.AnyEvent.type = XEventName.ClientMessage;
 819                         xevent.AnyEvent.display = display;
 820                         xevent.ClientMessageEvent.window = source;
 821                         xevent.ClientMessageEvent.message_type = XdndStatus;
 822                         xevent.ClientMessageEvent.format = 32;
 823                         xevent.ClientMessageEvent.ptr1 = toplevel;
 824                         if (effect != DragDropEffects.None)
 825                                 xevent.ClientMessageEvent.ptr2 = (IntPtr) 1;
 826
 827                         xevent.ClientMessageEvent.ptr5 = ActionFromEffect (effect);
 828                         XSendEvent (display, source, false, 0, ref xevent);
 829                 }
 830
 831                 private void SendEnter (IntPtr handle, IntPtr from, IntPtr [] supported)
 832                 {
 833                         XEvent xevent = new XEvent ();
 834
 835                         xevent.AnyEvent.type = XEventName.ClientMessage;
 836                         xevent.AnyEvent.display = display;
 837                         xevent.ClientMessageEvent.window = handle;
 838                         xevent.ClientMessageEvent.message_type = XdndEnter;
 839                         xevent.ClientMessageEvent.format = 32;
 840                         xevent.ClientMessageEvent.ptr1 = from;
 841
 842                         // (int) xevent.ClientMessageEvent.ptr2 & 0x1)
 843                         // int ptr2 = 0x1;
 844                         // xevent.ClientMessageEvent.ptr2 = (IntPtr) ptr2;
 845                         // (e)->xclient.data.l[1] = ((e)->xclient.data.l[1] & ~(0xFF << 24)) | ((v) << 24)
 846                         xevent.ClientMessageEvent.ptr2 = (IntPtr) (XdndVersion [0] << 24);
 847
 848                         if (supported.Length > 0)
 849                                 xevent.ClientMessageEvent.ptr3 = supported [0];
 850                         if (supported.Length > 1)
 851                                 xevent.ClientMessageEvent.ptr4 = supported [1];
 852                         if (supported.Length > 2)
 853                                 xevent.ClientMessageEvent.ptr5 = supported [2];
 854
 855                         XSendEvent (display, handle, false, 0, ref xevent);
 856                 }
 857
 858                 private void SendDrop (IntPtr handle, IntPtr from, IntPtr time)
 859                 {
 860                         XEvent xevent = new XEvent ();
 861
 862                         xevent.AnyEvent.type = XEventName.ClientMessage;
 863                         xevent.AnyEvent.display = display;
 864                         xevent.ClientMessageEvent.window = handle;
 865                         xevent.ClientMessageEvent.message_type = XdndDrop;
 866                         xevent.ClientMessageEvent.format = 32;
 867                         xevent.ClientMessageEvent.ptr1 = from;
 868                         xevent.ClientMessageEvent.ptr3 = time;
 869
 870                         XSendEvent (display, handle, false, 0, ref xevent);
 871                 }
 872
 873                 private void SendPosition (IntPtr handle, IntPtr from, IntPtr action, int x, int y, IntPtr time)
 874                 {
 875                         XEvent xevent = new XEvent ();
 876
 877                         xevent.AnyEvent.type = XEventName.ClientMessage;
 878                         xevent.AnyEvent.display = display;
 879                         xevent.ClientMessageEvent.window = handle;
 880                         xevent.ClientMessageEvent.message_type = XdndPosition;
 881                         xevent.ClientMessageEvent.format = 32;
 882                         xevent.ClientMessageEvent.ptr1 = from;
 883                         xevent.ClientMessageEvent.ptr3 = (IntPtr) ((x << 16) | (y & 0xFFFF));
 884                         xevent.ClientMessageEvent.ptr4 = time;
 885                         xevent.ClientMessageEvent.ptr5 = action;
 886
 887                         XSendEvent (display, handle, false, 0, ref xevent);
 888                 }
 889
 890                 private void SendLeave (IntPtr handle, IntPtr from)
 891                 {
 892                         XEvent xevent = new XEvent ();
 893
 894                         xevent.AnyEvent.type = XEventName.ClientMessage;
 895                         xevent.AnyEvent.display = display;
 896                         xevent.ClientMessageEvent.window = handle;
 897                         xevent.ClientMessageEvent.message_type = XdndLeave;
 898                         xevent.ClientMessageEvent.format = 32;
 899                         xevent.ClientMessageEvent.ptr1 = from;
 900
 901                         XSendEvent (display, handle, false, 0, ref xevent);
 902                 }
 903
 904                 private void SendFinished ()
 905                 {
 906                         XEvent xevent = new XEvent ();
 907
 908                         xevent.AnyEvent.type = XEventName.ClientMessage;
 909                         xevent.AnyEvent.display = display;
 910                         xevent.ClientMessageEvent.window = source;
 911                         xevent.ClientMessageEvent.message_type = XdndFinished;
 912                         xevent.ClientMessageEvent.format = 32;
 913                         xevent.ClientMessageEvent.ptr1 = toplevel;
 914
 915                         XSendEvent (display, source, false, 0, ref xevent);
 916                 }
 917
 918                 // There is a somewhat decent amount of overhead
 919                 // involved in setting up dnd so we do it lazily
 920                 // as a lot of applications do not even use it.
 921                 private void Init ()
 922                 {
 923                         XdndAware = XInternAtom (display, "XdndAware", false);
 924                         XdndEnter = XInternAtom (display, "XdndEnter", false);
 925                         XdndLeave = XInternAtom (display, "XdndLeave", false);
 926                         XdndPosition = XInternAtom (display, "XdndPosition", false);
 927                         XdndStatus = XInternAtom (display, "XdndStatus", false);
 928                         XdndDrop = XInternAtom (display, "XdndDrop", false);
 929                         XdndSelection = XInternAtom (display, "XdndSelection", false);
 930                         XdndFinished = XInternAtom (display, "XdndFinished", false);
 931                         XdndTypeList = XInternAtom (display, "XdndTypeList", false);
 932                         XdndActionCopy = XInternAtom (display, "XdndActionCopy", false);
 933                         XdndActionMove = XInternAtom (display, "XdndActionMove", false);
 934                         XdndActionLink = XInternAtom (display, "XdndActionLink", false);
 935                         XdndActionPrivate = XInternAtom (display, "XdndActionPrivate", false);
 936                         XdndActionList = XInternAtom (display, "XdndActionList", false);
 937                         XdndActionDescription = XInternAtom (display, "XdndActionDescription", false);
 938                         XdndActionAsk = XInternAtom (display, "XdndActionAsk", false);
 939
 940                 foreach (MimeHandler handler in MimeHandlers) {
 941                                 handler.Type = XInternAtom (display, handler.Name, false);
 942                                 handler.NonProtocol = XInternAtom (display,
 943                                                 String.Concat ("MWFNonP+", handler.Name), false);
 944                         }
 945
 946                 }
 947
 948                 private IntPtr [] SourceSupportedList (ref XEvent xevent)
 949                 {
 950                         IntPtr [] res;
 951
 952
 953                         if (((int) xevent.ClientMessageEvent.ptr2 & 0x1) == 0) {
 954                                 res = new IntPtr [3];
 955                                 res [0] = xevent.ClientMessageEvent.ptr3;
 956                                 res [1] = xevent.ClientMessageEvent.ptr4;
 957                                 res [2] = xevent.ClientMessageEvent.ptr5;
 958                         } else {
 959                                 IntPtr type;
 960                                 int format, count, remaining;
 961                                 IntPtr data = IntPtr.Zero;
 962
 963                                 XGetWindowProperty (display, source, XdndTypeList,
 964                                                 0, 32, false, (IntPtr) Atom.XA_ATOM,
 965                                                 out type, out format, out count,
 966                                                 out remaining, out data);
 967
 968                                 res = new IntPtr [count];
 969                                 for (int i = 0; i < count; i++) {
 970                                         res [i] = (IntPtr) Marshal.ReadInt32 (data, i *
 971                                                         Marshal.SizeOf (typeof (int)));
 972                                 }
 973
 974                                 XFree (data);
 975                         }
 976
 977                         return res;
 978                 }
 979
 980                 private string GetText (ref XEvent xevent, bool unicode)
 981                 {
 982                         int nread = 0;
 983                         int nitems;
 984                         int bytes_after;
 985
 986                         StringBuilder builder = new StringBuilder ();
 987                         do {
 988                                 IntPtr actual_type;
 989                                 int actual_fmt;
 990                                 IntPtr data = IntPtr.Zero;
 991
 992                                 if (0 != XGetWindowProperty (display,
 993                                                     xevent.AnyEvent.window,
 994                                                     (IntPtr) xevent.SelectionEvent.property,
 995                                                     0, 0xffffff, false,
 996                                                     (IntPtr) Atom.AnyPropertyType, out actual_type,
 997                                                     out actual_fmt, out nitems, out bytes_after,
 998                                                     out data)) {
 999                                         XFree (data);
1000                                         break;
1001                                 }
1002
1003                                 if (unicode)
1004                                         builder.Append (Marshal.PtrToStringUni (data));
1005                                 else
1006                                         builder.Append (Marshal.PtrToStringAnsi (data));
1007                                 nread += nitems;
1008
1009                                 XFree (data);
1010                         } while (bytes_after > 0);
1011                         if (nread == 0)
1012                                 return null;
1013                         return builder.ToString ();
1014                 }
1015
1016                 private MemoryStream GetData (ref XEvent xevent)
1017                 {
1018                         int nread = 0;
1019                         int nitems;
1020                         int bytes_after;
1021
1022                         MemoryStream res = new MemoryStream ();
1023                         do {
1024                                 IntPtr actual_type;
1025                                 int actual_fmt;
1026                                 IntPtr data = IntPtr.Zero;
1027
1028                                 if (0 != XGetWindowProperty (display,
1029                                                     xevent.AnyEvent.window,
1030                                                     (IntPtr) xevent.SelectionEvent.property,
1031                                                     0, 0xffffff, false,
1032                                                     (IntPtr) Atom.AnyPropertyType, out actual_type,
1033                                                     out actual_fmt, out nitems, out bytes_after,
1034                                                     out data)) {
1035                                         XFree (data);
1036                                         break;
1037                                 }
1038
1039                                 for (int i = 0; i < nitems; i++)
1040                                         res.WriteByte (Marshal.ReadByte (data, i));
1041                                 nread += nitems;
1042
1043                                 XFree (data);
1044                         } while (bytes_after > 0);
1045                         return res;
1046                 }
1047
1048                 private Control MwfWindow (IntPtr window)
1049                 {
1050                         Hwnd hwnd = Hwnd.ObjectFromHandle (window);
1051                         if (hwnd == null)
1052                                 return null;
1053
1054                         Control res = Control.FromHandle (hwnd.client_window);
1055                         return res;
1056                 }
1057
1058                 private bool IsWindowDndAware (IntPtr handle)
1059                 {
1060                         bool res = true;
1061                         // Check the version number, we need greater than 3
1062                         IntPtr actual;
1063                         int format, count, remaining;
1064                         IntPtr data = IntPtr.Zero;
1065
1066                         XGetWindowProperty (display, handle, XdndAware, 0, 0x8000000, false,
1067                                         (IntPtr) Atom.XA_ATOM, out actual, out format,
1068                                         out count, out remaining, out data);
1069
1070                         if (actual != (IntPtr) Atom.XA_ATOM || format != 32 ||
1071                                         count == 0 || data == IntPtr.Zero) {
1072                                 if (data != IntPtr.Zero)
1073                                         XFree (data);
1074                                 return false;
1075                         }
1076
1077                         int version = Marshal.ReadInt32 (data, 0);
1078
1079                         if (version < 3) {
1080                                 Console.Error.WriteLine ("XDND Version too old (" + version + ").");
1081                                 XFree (data);
1082                                 return false;
1083                         }
1084
1085                         // First type is actually the XDND version
1086                         if (count > 1) {
1087                                 res = false;
1088                                 for (int i = 1; i < count; i++) {
1089                                         IntPtr type = (IntPtr) Marshal.ReadInt32 (data, i *
1090                                                         Marshal.SizeOf (typeof (int)));
1091                                         for (int j = 0; j < drag_data.SupportedTypes.Length; j++) {
1092                                                 if (drag_data.SupportedTypes [j] == type) {
1093                                                         res = true;
1094                                                         break;
1095                                                 }
1096                                         }
1097                                 }
1098                         }
1099
1100                         XFree (data);
1101                         return res;
1102                 }
1103
1104                 private IntPtr [] DetermineSupportedTypes (object data)
1105                 {
1106                         ArrayList res = new ArrayList ();
1107
1108                         if (data is string) {
1109                                 MimeHandler handler = FindHandler ("text/plain");
1110                                 if (handler != null)
1111                                         res.Add (handler.Type);
1112                         }/* else if (data is Bitmap)
1113                                 res.Add (data);
1114
1115                          */
1116
1117                         if (data is IDataObject) {
1118
1119
1120                         }
1121
1122                         if (data is ISerializable) {
1123                                 MimeHandler handler = FindHandler ("application/x-mono-serialized-object");
1124                                 if (handler != null)
1125                                         res.Add (handler.Type);
1126                         }
1127
1128                         return (IntPtr []) res.ToArray (typeof (IntPtr));
1129                 }
1130
1131                 [DllImport ("libX11")]
1132                 private extern static string XGetAtomName (IntPtr display, IntPtr atom);
1133
1134                 [DllImport ("libX11")]
1135                 private extern static IntPtr XInternAtom (IntPtr display, string atom_name, bool only_if_exists);
1136
1137                 [DllImport ("libX11")]
1138                 private extern static int XChangeProperty (IntPtr display, IntPtr window, IntPtr property,
1139                                 IntPtr format, int type, PropertyMode  mode, uint [] atoms, int nelements);
1140
1141                 [DllImport ("libX11")]
1142                 private extern static int XGetWindowProperty (IntPtr display, IntPtr window,
1143                                 IntPtr atom, int long_offset, int long_length, bool delete,
1144                                 IntPtr req_type, out IntPtr actual_type, out int actual_format,
1145                                 out int nitems, out int bytes_after, out IntPtr prop);
1146
1147                 [DllImport ("libX11")]
1148                 internal extern static int XSendEvent (IntPtr display, IntPtr window,
1149                                 bool propagate, EventMask event_mask, ref XEvent send_event);
1150
1151                 [DllImport ("libX11")]
1152                 internal extern static int XConvertSelection (IntPtr display, IntPtr selection,
1153                                 IntPtr target, IntPtr property, IntPtr requestor, int time);
1154
1155                 [DllImport ("libX11")]
1156                 internal extern static IntPtr XGetSelectionOwner (IntPtr display, IntPtr selection);
1157
1158                 [DllImport ("libX11")]
1159                 internal extern static int XGrabPointer (IntPtr display, IntPtr window,
1160                                 bool owner_events, EventMask event_mask, GrabMode pointer_mode,
1161                                 GrabMode keyboard_mode, IntPtr confine_to, IntPtr cursor, uint timestamp);
1162
1163                 [DllImport ("libX11")]
1164                 internal extern static bool XQueryPointer (IntPtr display, IntPtr window, out IntPtr root,
1165                                 out IntPtr child, out int root_x, out int root_y, out int win_x,
1166                                 out int win_y, out int keys_buttons);
1167
1168                 [DllImport ("libX11")]
1169                 internal extern static int XAllowEvents (IntPtr display, int event_mode, IntPtr time);
1170
1171                 [DllImport ("libX11")]
1172                 internal extern static int XFree(IntPtr data);
1173
1174                 [DllImport ("libX11")]
1175                 internal extern static int XFetchName (IntPtr display, IntPtr window, ref IntPtr window_name);
1176                 [DllImport ("libX11")]
1177                 internal extern static int XChangeActivePointerGrab (IntPtr display, EventMask event_mask, IntPtr cursor, IntPtr time);
1178         }
1179
1180 }