WINGs/dragsource.c

   1
   2 #include "wconfig.h"
   3 #include "WINGsP.h"
   4
   5 #include <X11/Xatom.h>
   6 #include <X11/cursorfont.h>
   7 #ifdef USE_XSHAPE
   8 #include <X11/extensions/shape.h>
   9 #endif
  10
  11 #define XDND_DESTINATION_RESPONSE_MAX_DELAY 10000
  12 #define MIN_X_MOVE_OFFSET 5
  13 #define MIN_Y_MOVE_OFFSET 5
  14 #define MAX_SLIDEBACK_ITER 15
  15
  16 #define XDND_PROPERTY_FORMAT 32
  17 #define XDND_ACTION_DESCRIPTION_FORMAT 8
  18
  19 #define XDND_DEST_VERSION(dragInfo) dragInfo->protocolVersion
  20 #define XDND_SOURCE_INFO(dragInfo) dragInfo->sourceInfo
  21 #define XDND_DEST_WIN(dragInfo) dragInfo->sourceInfo->destinationWindow
  22 #define XDND_SOURCE_ACTION(dragInfo) dragInfo->sourceAction
  23 #define XDND_DEST_ACTION(dragInfo) dragInfo->destinationAction
  24 #define XDND_SOURCE_VIEW(dragInfo) dragInfo->sourceInfo->sourceView
  25 #define XDND_SOURCE_STATE(dragInfo) dragInfo->sourceInfo->state
  26 #define XDND_SELECTION_PROCS(dragInfo) dragInfo->sourceInfo->selectionProcs
  27 #define XDND_DRAG_ICON(dragInfo) dragInfo->sourceInfo->icon
  28 #define XDND_MOUSE_OFFSET(dragInfo) dragInfo->sourceInfo->mouseOffset
  29 #define XDND_DRAG_CURSOR(dragInfo) dragInfo->sourceInfo->dragCursor
  30 #define XDND_DRAG_ICON_POS(dragInfo) dragInfo->sourceInfo->imageLocation
  31 #define XDND_NO_POS_ZONE(dragInfo) dragInfo->sourceInfo->noPositionMessageZone
  32 #define XDND_TIMESTAMP(dragInfo) dragInfo->timestamp
  33 #define XDND_3_TYPES(dragInfo) dragInfo->sourceInfo->firstThreeTypes
  34 #define XDND_SOURCE_VIEW_STORED(dragInfo) dragInfo->sourceInfo != NULL \
  35     && dragInfo->sourceInfo->sourceView != NULL
  36
  37 static WMHandlerID dndSourceTimer = NULL;
  38
  39 static void *idleState(WMView * srcView, XClientMessageEvent * event, WMDraggingInfo * info);
  40 static void *dropAllowedState(WMView * srcView, XClientMessageEvent * event, WMDraggingInfo * info);
  41 static void *finishDropState(WMView * srcView, XClientMessageEvent * event, WMDraggingInfo * info);
  42
  43 #ifdef XDND_DEBUG
  44 static const char *stateName(W_DndState * state)
  45 {
  46         if (state == NULL)
  47                 return "no state defined";
  48
  49         if (state == idleState)
  50                 return "idleState";
  51
  52         if (state == dropAllowedState)
  53                 return "dropAllowedState";
  54
  55         if (state == finishDropState)
  56                 return "finishDropState";
  57
  58         return "unknown state";
  59 }
  60 #endif
  61
  62 static WMScreen *sourceScreen(WMDraggingInfo * info)
  63 {
  64         return W_VIEW_SCREEN(XDND_SOURCE_VIEW(info));
  65 }
  66
  67 static void endDragProcess(WMDraggingInfo * info, Bool deposited)
  68 {
  69         WMView *view = XDND_SOURCE_VIEW(info);
  70         WMScreen *scr = W_VIEW_SCREEN(XDND_SOURCE_VIEW(info));
  71
  72         /* free selection handler while view exists */
  73         WMDeleteSelectionHandler(view, scr->xdndSelectionAtom, CurrentTime);
  74         wfree(XDND_SELECTION_PROCS(info));
  75
  76         if (XDND_DRAG_CURSOR(info) != None) {
  77                 XFreeCursor(scr->display, XDND_DRAG_CURSOR(info));
  78                 XDND_DRAG_CURSOR(info) = None;
  79         }
  80
  81         if (view->dragSourceProcs->endedDrag != NULL) {
  82                 /* this can destroy source view (with a "move" action for example) */
  83                 view->dragSourceProcs->endedDrag(view, &XDND_DRAG_ICON_POS(info), deposited);
  84         }
  85
  86         /* clear remaining draggging infos */
  87         wfree(XDND_SOURCE_INFO(info));
  88         XDND_SOURCE_INFO(info) = NULL;
  89 }
  90
  91 /* ----- drag cursor ----- */
  92 static void initDragCursor(WMDraggingInfo * info)
  93 {
  94         WMScreen *scr = sourceScreen(info);
  95         XColor cursorFgColor, cursorBgColor;
  96
  97         /* green */
  98         cursorFgColor.red = 0x4500;
  99         cursorFgColor.green = 0xb000;
 100         cursorFgColor.blue = 0x4500;
 101
 102         /* white */
 103         cursorBgColor.red = 0xffff;
 104         cursorBgColor.green = 0xffff;
 105         cursorBgColor.blue = 0xffff;
 106
 107         XDND_DRAG_CURSOR(info) = XCreateFontCursor(scr->display, XC_left_ptr);
 108         XRecolorCursor(scr->display, XDND_DRAG_CURSOR(info), &cursorFgColor, &cursorBgColor);
 109
 110         XFlush(scr->display);
 111 }
 112
 113 static void recolorCursor(WMDraggingInfo * info, Bool dropIsAllowed)
 114 {
 115         WMScreen *scr = sourceScreen(info);
 116
 117         if (dropIsAllowed) {
 118                 XDefineCursor(scr->display, scr->rootWin, XDND_DRAG_CURSOR(info));
 119         } else {
 120                 XDefineCursor(scr->display, scr->rootWin, scr->defaultCursor);
 121         }
 122
 123         XFlush(scr->display);
 124 }
 125
 126 /* ----- end of drag cursor ----- */
 127
 128 /* ----- selection procs ----- */
 129 static WMData *convertSelection(WMView * view, Atom selection, Atom target, void *cdata, Atom * type)
 130 {
 131         WMScreen *scr;
 132         WMData *data;
 133         char *typeName;
 134
 135         /* Parameter not used, but tell the compiler that it is ok */
 136         (void) selection;
 137         (void) cdata;
 138
 139         scr = W_VIEW_SCREEN(view);
 140         typeName = XGetAtomName(scr->display, target);
 141
 142         *type = target;
 143
 144         if (view->dragSourceProcs->fetchDragData != NULL) {
 145                 data = view->dragSourceProcs->fetchDragData(view, typeName);
 146         } else {
 147                 data = NULL;
 148         }
 149
 150         if (typeName != NULL)
 151                 XFree(typeName);
 152
 153         return data;
 154 }
 155
 156 static void selectionLost(WMView * view, Atom selection, void *cdata)
 157 {
 158         /* Parameter not used, but tell the compiler that it is ok */
 159         (void) view;
 160         (void) selection;
 161         (void) cdata;
 162
 163         wwarning("DND selection lost during drag operation...");
 164 }
 165
 166 static void selectionDone(WMView * view, Atom selection, Atom target, void *cdata)
 167 {
 168         /* Parameter not used, but tell the compiler that it is ok */
 169         (void) view;
 170         (void) selection;
 171         (void) target;
 172         (void) cdata;
 173
 174 #ifdef XDND_DEBUG
 175         printf("selection done\n");
 176 #endif
 177 }
 178
 179 /* ----- end of selection procs ----- */
 180
 181 /* ----- visual part ----- */
 182
 183 static Window makeDragIcon(WMScreen * scr, WMPixmap * pixmap)
 184 {
 185         Window window;
 186         WMSize size;
 187         unsigned long flags;
 188         XSetWindowAttributes attribs;
 189
 190         if (!pixmap) {
 191                 pixmap = scr->defaultObjectIcon;
 192         }
 193
 194         size = WMGetPixmapSize(pixmap);
 195
 196         flags = CWSaveUnder | CWBackPixmap | CWOverrideRedirect | CWColormap;
 197         attribs.save_under = True;
 198         attribs.background_pixmap = pixmap->pixmap;
 199         attribs.override_redirect = True;
 200         attribs.colormap = scr->colormap;
 201
 202         window = XCreateWindow(scr->display, scr->rootWin, 0, 0, size.width,
 203                                size.height, 0, scr->depth, InputOutput, scr->visual, flags, &attribs);
 204
 205 #ifdef USE_XSHAPE
 206         if (pixmap->mask) {
 207                 XShapeCombineMask(scr->display, window, ShapeBounding, 0, 0, pixmap->mask, ShapeSet);
 208         }
 209 #endif
 210
 211         return window;
 212 }
 213
 214 static void slideWindow(Display * dpy, Window win, int srcX, int srcY, int dstX, int dstY)
 215 {
 216         double x, y, dx, dy;
 217         int i;
 218         int iterations;
 219
 220         iterations = WMIN(MAX_SLIDEBACK_ITER, WMAX(abs(dstX - srcX), abs(dstY - srcY)));
 221
 222         x = srcX;
 223         y = srcY;
 224
 225         dx = (double)(dstX - srcX) / iterations;
 226         dy = (double)(dstY - srcY) / iterations;
 227
 228         for (i = 0; i <= iterations; i++) {
 229                 XMoveWindow(dpy, win, x, y);
 230                 XFlush(dpy);
 231
 232                 wusleep(800);
 233
 234                 x += dx;
 235                 y += dy;
 236         }
 237 }
 238
 239 static int getInitialDragImageCoord(int viewCoord, int mouseCoord, int viewSize, int iconSize)
 240 {
 241         if (iconSize >= viewSize) {
 242                 /* center icon coord on view */
 243                 return viewCoord - iconSize / 2;
 244         } else {
 245                 /* try to center icon on mouse pos */
 246
 247                 if (mouseCoord - iconSize / 2 <= viewCoord)
 248                         /* if icon was centered on mouse, it would be off view
 249                            thus, put icon left (resp. top) side
 250                            at view (resp. top) side */
 251                         return viewCoord;
 252
 253                 else if (mouseCoord + iconSize / 2 >= viewCoord + viewSize)
 254                         /* if icon was centered on mouse, it would be off view
 255                            thus, put icon right (resp. bottom) side
 256                            at view right (resp. bottom) side */
 257                         return viewCoord + viewSize - iconSize;
 258
 259                 else
 260                         return mouseCoord - iconSize / 2;
 261         }
 262
 263 }
 264
 265 static void initDragImagePos(WMView * view, WMDraggingInfo * info, XEvent * event)
 266 {
 267         WMSize iconSize = WMGetPixmapSize(view->dragImage);
 268         WMSize viewSize = WMGetViewSize(view);
 269         WMPoint viewPos;
 270         Window foo;
 271
 272         XTranslateCoordinates(W_VIEW_SCREEN(view)->display,
 273                               WMViewXID(view), W_VIEW_SCREEN(view)->rootWin,
 274                               0, 0, &(viewPos.x), &(viewPos.y), &foo);
 275
 276         /* set icon pos */
 277         XDND_DRAG_ICON_POS(info).x =
 278             getInitialDragImageCoord(viewPos.x, event->xmotion.x_root, viewSize.width, iconSize.width);
 279
 280         XDND_DRAG_ICON_POS(info).y =
 281             getInitialDragImageCoord(viewPos.y, event->xmotion.y_root, viewSize.height, iconSize.height);
 282
 283         /* set mouse offset relative to icon */
 284         XDND_MOUSE_OFFSET(info).x = event->xmotion.x_root - XDND_DRAG_ICON_POS(info).x;
 285         XDND_MOUSE_OFFSET(info).y = event->xmotion.y_root - XDND_DRAG_ICON_POS(info).y;
 286 }
 287
 288 static void refreshDragImage(WMView * view, WMDraggingInfo * info)
 289 {
 290         WMScreen *scr = W_VIEW_SCREEN(view);
 291
 292         XMoveWindow(scr->display, XDND_DRAG_ICON(info), XDND_DRAG_ICON_POS(info).x, XDND_DRAG_ICON_POS(info).y);
 293 }
 294
 295 static void startDragImage(WMView * view, WMDraggingInfo * info, XEvent * event)
 296 {
 297         WMScreen *scr = W_VIEW_SCREEN(view);
 298
 299         XDND_DRAG_ICON(info) = makeDragIcon(scr, view->dragImage);
 300         initDragImagePos(view, info, event);
 301         refreshDragImage(view, info);
 302         XMapRaised(scr->display, XDND_DRAG_ICON(info));
 303
 304         initDragCursor(info);
 305 }
 306
 307 static void endDragImage(WMDraggingInfo * info, Bool slideBack)
 308 {
 309         WMView *view = XDND_SOURCE_VIEW(info);
 310         Display *dpy = W_VIEW_SCREEN(view)->display;
 311
 312         if (slideBack) {
 313                 WMPoint toLocation;
 314                 Window foo;
 315
 316                 XTranslateCoordinates(W_VIEW_SCREEN(view)->display,
 317                                       WMViewXID(view), W_VIEW_SCREEN(view)->rootWin,
 318                                       0, 0, &(toLocation.x), &(toLocation.y), &foo);
 319
 320                 slideWindow(dpy, XDND_DRAG_ICON(info),
 321                             XDND_DRAG_ICON_POS(info).x, XDND_DRAG_ICON_POS(info).y, toLocation.x, toLocation.y);
 322         }
 323
 324         XDestroyWindow(dpy, XDND_DRAG_ICON(info));
 325 }
 326
 327 /* ----- end of visual part ----- */
 328
 329 /* ----- messages ----- */
 330
 331 /* send a DnD message to the destination window */
 332 static Bool
 333 sendDnDClientMessage(WMDraggingInfo * info, Atom message,
 334                      unsigned long data1, unsigned long data2, unsigned long data3, unsigned long data4)
 335 {
 336         Display *dpy = sourceScreen(info)->display;
 337         Window srcWin = WMViewXID(XDND_SOURCE_VIEW(info));
 338         Window destWin = XDND_DEST_WIN(info);
 339
 340         if (!W_SendDnDClientMessage(dpy, destWin, message, srcWin, data1, data2, data3, data4)) {
 341                 /* drop failed */
 342                 recolorCursor(info, False);
 343                 endDragImage(info, True);
 344                 endDragProcess(info, False);
 345                 return False;
 346         }
 347
 348         return True;
 349 }
 350
 351 static Bool sendEnterMessage(WMDraggingInfo * info)
 352 {
 353         WMScreen *scr = sourceScreen(info);
 354         unsigned long version;
 355
 356         if (XDND_DEST_VERSION(info) > 2) {
 357                 if (XDND_DEST_VERSION(info) < XDND_VERSION)
 358                         version = XDND_DEST_VERSION(info);
 359                 else
 360                         version = XDND_VERSION;
 361         } else {
 362                 version = 3;
 363         }
 364
 365         return sendDnDClientMessage(info, scr->xdndEnterAtom, (version << 24) | 1,      /* 1: support of type list */
 366                                     XDND_3_TYPES(info)[0], XDND_3_TYPES(info)[1], XDND_3_TYPES(info)[2]);
 367 }
 368
 369 static Bool sendPositionMessage(WMDraggingInfo * info, WMPoint * mousePos)
 370 {
 371         WMScreen *scr = sourceScreen(info);
 372         WMRect *noPosZone = &(XDND_NO_POS_ZONE(info));
 373
 374         if (noPosZone->size.width != 0 || noPosZone->size.height != 0) {
 375                 if (mousePos->x < noPosZone->pos.x || mousePos->x > (noPosZone->pos.x + noPosZone->size.width)
 376                     || mousePos->y < noPosZone->pos.y || mousePos->y > (noPosZone->pos.y + noPosZone->size.height)) {
 377                         /* send position if out of zone defined by destination */
 378                         return sendDnDClientMessage(info, scr->xdndPositionAtom,
 379                                                     0,
 380                                                     mousePos->x << 16 | mousePos->y,
 381                                                     XDND_TIMESTAMP(info), XDND_SOURCE_ACTION(info));
 382                 }
 383
 384                 /* Nothing to send, always succeed */
 385                 return True;
 386
 387         }
 388
 389         /* send position on each move */
 390         return sendDnDClientMessage(info, scr->xdndPositionAtom,
 391                                     0,
 392                                     mousePos->x << 16 | mousePos->y,
 393                                     XDND_TIMESTAMP(info), XDND_SOURCE_ACTION(info));
 394 }
 395
 396 static Bool sendLeaveMessage(WMDraggingInfo * info)
 397 {
 398         WMScreen *scr = sourceScreen(info);
 399
 400         return sendDnDClientMessage(info, scr->xdndLeaveAtom, 0, 0, 0, 0);
 401 }
 402
 403 static Bool sendDropMessage(WMDraggingInfo * info)
 404 {
 405         WMScreen *scr = sourceScreen(info);
 406
 407         return sendDnDClientMessage(info, scr->xdndDropAtom, 0, XDND_TIMESTAMP(info), 0, 0);
 408 }
 409
 410 /* ----- end of messages ----- */
 411
 412 static Atom *getTypeAtomList(WMScreen * scr, WMView * view, int *count)
 413 {
 414         WMArray *types;
 415         Atom *typeAtoms;
 416         int i;
 417
 418         types = view->dragSourceProcs->dropDataTypes(view);
 419
 420         if (types != NULL) {
 421                 *count = WMGetArrayItemCount(types);
 422                 if (*count > 0) {
 423                         typeAtoms = wmalloc((*count) * sizeof(Atom));
 424                         for (i = 0; i < *count; i++) {
 425                                 typeAtoms[i] = XInternAtom(scr->display, WMGetFromArray(types, i), False);
 426                         }
 427
 428                         /* WMFreeArray(types); */
 429                         return typeAtoms;
 430                 }
 431
 432                 /* WMFreeArray(types); */
 433         }
 434
 435         *count = 1;
 436         typeAtoms = wmalloc(sizeof(Atom));
 437         *typeAtoms = None;
 438
 439         return typeAtoms;
 440 }
 441
 442 static void registerDropTypes(WMScreen * scr, WMView * view, WMDraggingInfo * info)
 443 {
 444         Atom *typeList;
 445         int i, count;
 446
 447         typeList = getTypeAtomList(scr, view, &count);
 448
 449         /* store the first 3 types */
 450         for (i = 0; i < 3 && i < count; i++)
 451                 XDND_3_TYPES(info)[i] = typeList[i];
 452
 453         for (; i < 3; i++)
 454                 XDND_3_TYPES(info)[i] = None;
 455
 456         /* store the entire type list */
 457         XChangeProperty(scr->display,
 458                         WMViewXID(view),
 459                         scr->xdndTypeListAtom,
 460                         XA_ATOM, XDND_PROPERTY_FORMAT, PropModeReplace, (unsigned char *)typeList, count);
 461 }
 462
 463 static void registerOperationList(WMScreen * scr, WMView * view, WMArray * operationArray)
 464 {
 465         Atom *actionList;
 466         WMDragOperationType operation;
 467         int count = WMGetArrayItemCount(operationArray);
 468         int i;
 469
 470         actionList = wmalloc(sizeof(Atom) * count);
 471
 472         for (i = 0; i < count; i++) {
 473                 operation = WMGetDragOperationItemType(WMGetFromArray(operationArray, i));
 474                 actionList[i] = W_OperationToAction(scr, operation);
 475         }
 476
 477         XChangeProperty(scr->display,
 478                         WMViewXID(view),
 479                         scr->xdndActionListAtom,
 480                         XA_ATOM, XDND_PROPERTY_FORMAT, PropModeReplace, (unsigned char *)actionList, count);
 481 }
 482
 483 static void registerDescriptionList(WMScreen * scr, WMView * view, WMArray * operationArray)
 484 {
 485         char *text, *textListItem, *textList;
 486         int count = WMGetArrayItemCount(operationArray);
 487         int i;
 488         int size = 0;
 489
 490         /* size of XA_STRING info */
 491         for (i = 0; i < count; i++) {
 492                 size += strlen(WMGetDragOperationItemText(WMGetFromArray(operationArray, i))) + 1 /* NULL */;
 493         }
 494
 495         /* create text list */
 496         textList = wmalloc(size);
 497         textListItem = textList;
 498
 499         for (i = 0; i < count; i++) {
 500                 text = WMGetDragOperationItemText(WMGetFromArray(operationArray, i));
 501                 wstrlcpy(textListItem, text, size);
 502
 503                 /* to next text offset */
 504                 textListItem = &(textListItem[strlen(textListItem) + 1]);
 505         }
 506
 507         XChangeProperty(scr->display,
 508                         WMViewXID(view),
 509                         scr->xdndActionDescriptionAtom,
 510                         XA_STRING,
 511                         XDND_ACTION_DESCRIPTION_FORMAT, PropModeReplace, (unsigned char *)textList, size);
 512 }
 513
 514 /* called if wanted operation is WDOperationAsk */
 515 static void registerSupportedOperations(WMView * view)
 516 {
 517         WMScreen *scr = W_VIEW_SCREEN(view);
 518         WMArray *operationArray;
 519
 520         operationArray = view->dragSourceProcs->askedOperations(view);
 521
 522         registerOperationList(scr, view, operationArray);
 523         registerDescriptionList(scr, view, operationArray);
 524
 525         /* WMFreeArray(operationArray); */
 526 }
 527
 528 static void initSourceDragInfo(WMView * sourceView, WMDraggingInfo * info)
 529 {
 530         WMRect emptyZone;
 531
 532         XDND_SOURCE_INFO(info) = (W_DragSourceInfo *) wmalloc(sizeof(W_DragSourceInfo));
 533
 534         XDND_SOURCE_VIEW(info) = sourceView;
 535         XDND_DEST_WIN(info) = None;
 536         XDND_DRAG_ICON(info) = None;
 537
 538         XDND_SOURCE_ACTION(info) = W_OperationToAction(W_VIEW_SCREEN(sourceView),
 539                                                        sourceView->dragSourceProcs->
 540                                                        wantedDropOperation(sourceView));
 541
 542         XDND_DEST_ACTION(info) = None;
 543
 544         XDND_SOURCE_STATE(info) = idleState;
 545
 546         emptyZone.pos = wmkpoint(0, 0);
 547         emptyZone.size = wmksize(0, 0);
 548         XDND_NO_POS_ZONE(info) = emptyZone;
 549 }
 550
 551 /*
 552  Returned array is destroyed after dropDataTypes call
 553  */
 554 static WMArray *defDropDataTypes(WMView * self)
 555 {
 556         /* Parameter not used, but tell the compiler that it is ok */
 557         (void) self;
 558
 559         return NULL;
 560 }
 561
 562 static WMDragOperationType defWantedDropOperation(WMView * self)
 563 {
 564         /* Parameter not used, but tell the compiler that it is ok */
 565         (void) self;
 566
 567         return WDOperationNone;
 568 }
 569
 570 /*
 571  Must be defined if wantedDropOperation return WDOperationAsk
 572  (useless otherwise).
 573  Return a WMDragOperationItem array (destroyed after call).
 574  A WMDragOperationItem links a label to an operation.
 575  static WMArray*
 576  defAskedOperations(WMView *self); */
 577
 578 static Bool defAcceptDropOperation(WMView * self, WMDragOperationType allowedOperation)
 579 {
 580         /* Parameter not used, but tell the compiler that it is ok */
 581         (void) self;
 582         (void) allowedOperation;
 583
 584         return False;
 585 }
 586
 587 static void defBeganDrag(WMView * self, WMPoint * point)
 588 {
 589         /* Parameter not used, but tell the compiler that it is ok */
 590         (void) self;
 591         (void) point;
 592 }
 593
 594 static void defEndedDrag(WMView * self, WMPoint * point, Bool deposited)
 595 {
 596         /* Parameter not used, but tell the compiler that it is ok */
 597         (void) self;
 598         (void) point;
 599         (void) deposited;
 600 }
 601
 602 /*
 603  Returned data is not destroyed
 604  */
 605 static WMData *defFetchDragData(WMView * self, char *type)
 606 {
 607         /* Parameter not used, but tell the compiler that it is ok */
 608         (void) self;
 609         (void) type;
 610
 611         return NULL;
 612 }
 613
 614 void WMSetViewDragSourceProcs(WMView * view, WMDragSourceProcs * procs)
 615 {
 616         if (view->dragSourceProcs)
 617                 wfree(view->dragSourceProcs);
 618         view->dragSourceProcs = wmalloc(sizeof(WMDragSourceProcs));
 619
 620         *view->dragSourceProcs = *procs;
 621
 622         if (procs->dropDataTypes == NULL)
 623                 view->dragSourceProcs->dropDataTypes = defDropDataTypes;
 624
 625         if (procs->wantedDropOperation == NULL)
 626                 view->dragSourceProcs->wantedDropOperation = defWantedDropOperation;
 627
 628         /*
 629            Note: askedOperations can be NULL, if wantedDropOperation never returns
 630            WDOperationAsk.
 631          */
 632
 633         if (procs->acceptDropOperation == NULL)
 634                 view->dragSourceProcs->acceptDropOperation = defAcceptDropOperation;
 635
 636         if (procs->beganDrag == NULL)
 637                 view->dragSourceProcs->beganDrag = defBeganDrag;
 638
 639         if (procs->endedDrag == NULL)
 640                 view->dragSourceProcs->endedDrag = defEndedDrag;
 641
 642         if (procs->fetchDragData == NULL)
 643                 view->dragSourceProcs->fetchDragData = defFetchDragData;
 644 }
 645
 646 static Bool isXdndAware(WMScreen * scr, Window win)
 647 {
 648         Atom type;
 649         int format;
 650         unsigned long count, remain;
 651         unsigned char *winXdndVersion;
 652
 653         if (win == None)
 654                 return False;
 655
 656         XGetWindowProperty(scr->display, win, scr->xdndAwareAtom,
 657                            0, 1, False, XA_ATOM, &type, &format, &count, &remain, &winXdndVersion);
 658
 659         if (type != XA_ATOM || format != XDND_PROPERTY_FORMAT || count == 0 || !winXdndVersion) {
 660                 if (winXdndVersion)
 661                         XFree(winXdndVersion);
 662                 return False;
 663         }
 664
 665         XFree(winXdndVersion);
 666         return (count == 1);    /* xdnd version is set */
 667 }
 668
 669 static Window *windowChildren(Display * dpy, Window win, unsigned *nchildren)
 670 {
 671         Window *children;
 672         Window foo, bar;
 673
 674         if (!XQueryTree(dpy, win, &foo, &bar, &children, nchildren)) {
 675                 *nchildren = 0;
 676                 return NULL;
 677         } else
 678                 return children;
 679 }
 680
 681 static Window lookForAwareWindow(WMScreen * scr, WMPoint * mousePos, Window win)
 682 {
 683         int tmpx, tmpy;
 684         Window child;
 685
 686         /* Since xdnd v3, only the toplevel window should be aware */
 687         if (isXdndAware(scr, win))
 688                 return win;
 689
 690         /* inspect child under pointer */
 691         if (XTranslateCoordinates(scr->display, scr->rootWin, win, mousePos->x, mousePos->y, &tmpx, &tmpy, &child)) {
 692                 if (child == None)
 693                         return None;
 694                 else
 695                         return lookForAwareWindow(scr, mousePos, child);
 696         }
 697
 698         return None;
 699 }
 700
 701 static Window findDestination(WMDraggingInfo * info, WMPoint * mousePos)
 702 {
 703         WMScreen *scr = sourceScreen(info);
 704         unsigned nchildren;
 705         Window *children = windowChildren(scr->display, scr->rootWin, &nchildren);
 706         int i;
 707         XWindowAttributes attr;
 708
 709         if (isXdndAware(scr, scr->rootWin))
 710                 return scr->rootWin;
 711
 712         /* exclude drag icon (and upper) from search */
 713         for (i = nchildren - 1; i >= 0; i--) {
 714                 if (children[i] == XDND_DRAG_ICON(info)) {
 715                         i--;
 716                         break;
 717                 }
 718         }
 719
 720         if (i < 0) {
 721                 /* root window has no child under drag icon, and is not xdnd aware. */
 722                 return None;
 723         }
 724
 725         /* inspecting children, from upper to lower */
 726         for (; i >= 0; i--) {
 727                 if (XGetWindowAttributes(scr->display, children[i], &attr)
 728                     && attr.map_state == IsViewable
 729                     && mousePos->x >= attr.x
 730                     && mousePos->y >= attr.y
 731                     && mousePos->x < attr.x + attr.width && mousePos->y < attr.y + attr.height) {
 732                         return lookForAwareWindow(scr, mousePos, children[i]);
 733                 }
 734         }
 735
 736         /* No child window under drag pointer */
 737         return None;
 738 }
 739
 740 static void storeDestinationProtocolVersion(WMDraggingInfo * info)
 741 {
 742         Atom type;
 743         int format;
 744         unsigned long count, remain;
 745         unsigned char *winXdndVersion;
 746         WMScreen *scr = W_VIEW_SCREEN(XDND_SOURCE_VIEW(info));
 747
 748         wassertr(XDND_DEST_WIN(info) != None);
 749
 750         if (XGetWindowProperty(scr->display, XDND_DEST_WIN(info),
 751                                scr->xdndAwareAtom,
 752                                0, 1, False, XA_ATOM, &type, &format,
 753                                &count, &remain, &winXdndVersion) == Success) {
 754                 XDND_DEST_VERSION(info) = *winXdndVersion;
 755                 XFree(winXdndVersion);
 756         } else {
 757                 XDND_DEST_VERSION(info) = 0;
 758                 wwarning("failed to read XDND version of drop target");
 759         }
 760 }
 761
 762 static void initMotionProcess(WMView * view, WMDraggingInfo * info, XEvent * event, WMPoint * startLocation)
 763 {
 764         WMScreen *scr = W_VIEW_SCREEN(view);
 765
 766         /* take ownership of XdndSelection */
 767         XDND_SELECTION_PROCS(info) = (WMSelectionProcs *) wmalloc(sizeof(WMSelectionProcs));
 768         XDND_SELECTION_PROCS(info)->convertSelection = convertSelection;
 769         XDND_SELECTION_PROCS(info)->selectionLost = selectionLost;
 770         XDND_SELECTION_PROCS(info)->selectionDone = selectionDone;
 771         XDND_TIMESTAMP(info) = event->xmotion.time;
 772
 773         if (!WMCreateSelectionHandler(view, scr->xdndSelectionAtom, CurrentTime, XDND_SELECTION_PROCS(info), NULL)) {
 774                 wwarning("could not get ownership or DND selection");
 775                 return;
 776         }
 777
 778         registerDropTypes(scr, view, info);
 779
 780         if (XDND_SOURCE_ACTION(info) == W_VIEW_SCREEN(view)->xdndActionAsk)
 781                 registerSupportedOperations(view);
 782
 783         if (view->dragSourceProcs->beganDrag != NULL) {
 784                 view->dragSourceProcs->beganDrag(view, startLocation);
 785         }
 786 }
 787
 788 static void processMotion(WMDraggingInfo * info, WMPoint * mousePos)
 789 {
 790         Window newDestination = findDestination(info, mousePos);
 791
 792         W_DragSourceStopTimer();
 793
 794         if (newDestination != XDND_DEST_WIN(info)) {
 795                 recolorCursor(info, False);
 796
 797                 if (XDND_DEST_WIN(info) != None) {
 798                         /* leaving a xdnd window */
 799                         sendLeaveMessage(info);
 800                 }
 801
 802                 XDND_DEST_WIN(info) = newDestination;
 803                 XDND_DEST_ACTION(info) = None;
 804                 XDND_NO_POS_ZONE(info).size.width = 0;
 805                 XDND_NO_POS_ZONE(info).size.height = 0;
 806
 807                 if (newDestination != None) {
 808                         /* entering a xdnd window */
 809                         XDND_SOURCE_STATE(info) = idleState;
 810                         storeDestinationProtocolVersion(info);
 811
 812                         if (!sendEnterMessage(info)) {
 813                                 XDND_DEST_WIN(info) = None;
 814                                 return;
 815                         }
 816
 817                         W_DragSourceStartTimer(info);
 818                 } else {
 819                         XDND_SOURCE_STATE(info) = NULL;
 820                 }
 821         } else {
 822                 if (XDND_DEST_WIN(info) != None) {
 823                         if (!sendPositionMessage(info, mousePos)) {
 824                                 XDND_DEST_WIN(info) = None;
 825                                 return;
 826                         }
 827
 828                         W_DragSourceStartTimer(info);
 829                 }
 830         }
 831 }
 832
 833 static Bool processButtonRelease(WMDraggingInfo * info)
 834 {
 835         if (XDND_SOURCE_STATE(info) == dropAllowedState) {
 836                 /* begin drop */
 837                 W_DragSourceStopTimer();
 838
 839                 if (!sendDropMessage(info))
 840                         return False;
 841
 842                 W_DragSourceStartTimer(info);
 843                 return True;
 844         } else {
 845                 if (XDND_DEST_WIN(info) != None)
 846                         sendLeaveMessage(info);
 847
 848                 W_DragSourceStopTimer();
 849                 return False;
 850         }
 851 }
 852
 853 Bool WMIsDraggingFromView(WMView * view)
 854 {
 855         WMDraggingInfo *info = &W_VIEW_SCREEN(view)->dragInfo;
 856
 857         return (XDND_SOURCE_INFO(info) != NULL && XDND_SOURCE_STATE(info) != finishDropState);
 858         /* return W_VIEW_SCREEN(view)->dragInfo.sourceInfo != NULL; */
 859 }
 860
 861 void WMDragImageFromView(WMView * view, XEvent * event)
 862 {
 863         WMDraggingInfo *info = &W_VIEW_SCREEN(view)->dragInfo;
 864         WMPoint mouseLocation;
 865
 866         switch (event->type) {
 867         case ButtonPress:
 868                 if (event->xbutton.button == Button1) {
 869                         XEvent nextEvent;
 870
 871                         XPeekEvent(event->xbutton.display, &nextEvent);
 872
 873                         /* Initialize only if a drag really begins (avoid clicks) */
 874                         if (nextEvent.type == MotionNotify) {
 875                                 initSourceDragInfo(view, info);
 876                         }
 877                 }
 878
 879                 break;
 880
 881         case ButtonRelease:
 882                 if (WMIsDraggingFromView(view)) {
 883                         Bool dropBegan = processButtonRelease(info);
 884
 885                         recolorCursor(info, False);
 886                         if (dropBegan) {
 887                                 endDragImage(info, False);
 888                                 XDND_SOURCE_STATE(info) = finishDropState;
 889                         } else {
 890                                 /* drop failed */
 891                                 endDragImage(info, True);
 892                                 endDragProcess(info, False);
 893                         }
 894                 }
 895                 break;
 896
 897         case MotionNotify:
 898                 if (WMIsDraggingFromView(view)) {
 899                         mouseLocation = wmkpoint(event->xmotion.x_root, event->xmotion.y_root);
 900
 901                         if (abs(XDND_DRAG_ICON_POS(info).x - mouseLocation.x) >=
 902                             MIN_X_MOVE_OFFSET
 903                             || abs(XDND_DRAG_ICON_POS(info).y - mouseLocation.y) >= MIN_Y_MOVE_OFFSET) {
 904                                 if (XDND_DRAG_ICON(info) == None) {
 905                                         initMotionProcess(view, info, event, &mouseLocation);
 906                                         startDragImage(view, info, event);
 907                                 } else {
 908                                         XDND_DRAG_ICON_POS(info).x = mouseLocation.x - XDND_MOUSE_OFFSET(info).x;
 909                                         XDND_DRAG_ICON_POS(info).y = mouseLocation.y - XDND_MOUSE_OFFSET(info).y;
 910
 911                                         refreshDragImage(view, info);
 912                                         processMotion(info, &mouseLocation);
 913                                 }
 914                         }
 915                 }
 916                 break;
 917         }
 918 }
 919
 920 /* Minimal mouse events handler: no right or double-click detection,
 921  only drag is supported */
 922 static void dragImageHandler(XEvent * event, void *cdata)
 923 {
 924         WMView *view = (WMView *) cdata;
 925
 926         WMDragImageFromView(view, event);
 927 }
 928
 929 /* ----- source states ----- */
 930
 931 #ifdef XDND_DEBUG
 932 static void traceStatusMsg(Display * dpy, XClientMessageEvent * statusEvent)
 933 {
 934         printf("Xdnd status message:\n");
 935
 936         if (statusEvent->data.l[1] & 0x2UL)
 937                 printf("\tsend position on every move\n");
 938         else {
 939                 int x, y, w, h;
 940                 x = statusEvent->data.l[2] >> 16;
 941                 y = statusEvent->data.l[2] & 0xFFFFL;
 942                 w = statusEvent->data.l[3] >> 16;
 943                 h = statusEvent->data.l[3] & 0xFFFFL;
 944
 945                 printf("\tsend position out of ((%d,%d) , (%d,%d))\n", x, y, x + w, y + h);
 946         }
 947
 948         if (statusEvent->data.l[1] & 0x1L)
 949                 printf("\tallowed action: %s\n", XGetAtomName(dpy, statusEvent->data.l[4]));
 950         else
 951                 printf("\tno action allowed\n");
 952 }
 953 #endif
 954
 955 static void storeDropAction(WMDraggingInfo * info, Atom destAction)
 956 {
 957         WMView *sourceView = XDND_SOURCE_VIEW(info);
 958         WMScreen *scr = W_VIEW_SCREEN(sourceView);
 959
 960         if (sourceView->dragSourceProcs->acceptDropOperation != NULL) {
 961                 if (sourceView->dragSourceProcs->acceptDropOperation(sourceView,
 962                                                                      W_ActionToOperation(scr, destAction)))
 963                         XDND_DEST_ACTION(info) = destAction;
 964                 else
 965                         XDND_DEST_ACTION(info) = None;
 966         } else {
 967                 XDND_DEST_ACTION(info) = destAction;
 968         }
 969 }
 970
 971 static void storeStatusMessageInfos(WMDraggingInfo * info, XClientMessageEvent * statusEvent)
 972 {
 973         WMRect *noPosZone = &(XDND_NO_POS_ZONE(info));
 974
 975 #ifdef XDND_DEBUG
 976
 977         traceStatusMsg(sourceScreen(info)->display, statusEvent);
 978 #endif
 979
 980         if (statusEvent->data.l[1] & 0x2UL) {
 981                 /* bit 1 set: destination wants position messages on every move */
 982                 noPosZone->size.width = 0;
 983                 noPosZone->size.height = 0;
 984         } else {
 985                 /* don't send another position message while in given rectangle */
 986                 noPosZone->pos.x = statusEvent->data.l[2] >> 16;
 987                 noPosZone->pos.y = statusEvent->data.l[2] & 0xFFFFL;
 988                 noPosZone->size.width = statusEvent->data.l[3] >> 16;
 989                 noPosZone->size.height = statusEvent->data.l[3] & 0xFFFFL;
 990         }
 991
 992         if ((statusEvent->data.l[1] & 0x1L) || statusEvent->data.l[4] != None) {
 993                 /* destination accept drop */
 994                 storeDropAction(info, statusEvent->data.l[4]);
 995         } else {
 996                 XDND_DEST_ACTION(info) = None;
 997         }
 998 }
 999
1000 static void *idleState(WMView * view, XClientMessageEvent * event, WMDraggingInfo * info)
1001 {
1002         WMScreen *scr;
1003         Atom destMsg = event->message_type;
1004
1005         scr = W_VIEW_SCREEN(view);
1006
1007         if (destMsg == scr->xdndStatusAtom) {
1008                 storeStatusMessageInfos(info, event);
1009
1010                 if (XDND_DEST_ACTION(info) != None) {
1011                         recolorCursor(info, True);
1012                         W_DragSourceStartTimer(info);
1013                         return dropAllowedState;
1014                 } else {
1015                         /* drop denied */
1016                         recolorCursor(info, False);
1017                         return idleState;
1018                 }
1019         }
1020
1021         if (destMsg == scr->xdndFinishedAtom) {
1022                 wwarning("received xdndFinishedAtom before drop began");
1023         }
1024
1025         W_DragSourceStartTimer(info);
1026         return idleState;
1027 }
1028
1029 static void *dropAllowedState(WMView * view, XClientMessageEvent * event, WMDraggingInfo * info)
1030 {
1031         WMScreen *scr = W_VIEW_SCREEN(view);
1032         Atom destMsg = event->message_type;
1033
1034         if (destMsg == scr->xdndStatusAtom) {
1035                 storeStatusMessageInfos(info, event);
1036
1037                 if (XDND_DEST_ACTION(info) == None) {
1038                         /* drop denied */
1039                         recolorCursor(info, False);
1040                         return idleState;
1041                 }
1042         }
1043
1044         W_DragSourceStartTimer(info);
1045         return dropAllowedState;
1046 }
1047
1048 static void *finishDropState(WMView * view, XClientMessageEvent * event, WMDraggingInfo * info)
1049 {
1050         WMScreen *scr = W_VIEW_SCREEN(view);
1051         Atom destMsg = event->message_type;
1052
1053         if (destMsg == scr->xdndFinishedAtom) {
1054                 endDragProcess(info, True);
1055                 return NULL;
1056         }
1057
1058         W_DragSourceStartTimer(info);
1059         return finishDropState;
1060 }
1061
1062 /* ----- end of source states ----- */
1063
1064 /* ----- source timer ----- */
1065 static void dragSourceResponseTimeOut(void *source)
1066 {
1067         WMView *view = (WMView *) source;
1068         WMDraggingInfo *info = &(W_VIEW_SCREEN(view)->dragInfo);
1069
1070         wwarning("delay for drag destination response expired");
1071         sendLeaveMessage(info);
1072
1073         recolorCursor(info, False);
1074         if (XDND_SOURCE_STATE(info) == finishDropState) {
1075                 /* drop failed */
1076                 endDragImage(info, True);
1077                 endDragProcess(info, False);
1078         } else {
1079                 XDND_SOURCE_STATE(info) = idleState;
1080         }
1081 }
1082
1083 void W_DragSourceStopTimer()
1084 {
1085         if (dndSourceTimer != NULL) {
1086                 WMDeleteTimerHandler(dndSourceTimer);
1087                 dndSourceTimer = NULL;
1088         }
1089 }
1090
1091 void W_DragSourceStartTimer(WMDraggingInfo * info)
1092 {
1093         W_DragSourceStopTimer();
1094
1095         dndSourceTimer = WMAddTimerHandler(XDND_DESTINATION_RESPONSE_MAX_DELAY,
1096                                            dragSourceResponseTimeOut, XDND_SOURCE_VIEW(info));
1097 }
1098
1099 /* ----- End of Destination timer ----- */
1100
1101 void W_DragSourceStateHandler(WMDraggingInfo * info, XClientMessageEvent * event)
1102 {
1103         WMView *view;
1104         W_DndState *newState;
1105
1106         if (XDND_SOURCE_VIEW_STORED(info)) {
1107                 if (XDND_SOURCE_STATE(info) != NULL) {
1108                         view = XDND_SOURCE_VIEW(info);
1109 #ifdef XDND_DEBUG
1110
1111                         printf("current source state: %s\n", stateName(XDND_SOURCE_STATE(info)));
1112 #endif
1113
1114                         newState = (W_DndState *) XDND_SOURCE_STATE(info) (view, event, info);
1115
1116 #ifdef XDND_DEBUG
1117
1118                         printf("new source state: %s\n", stateName(newState));
1119 #endif
1120
1121                         if (newState != NULL)
1122                                 XDND_SOURCE_STATE(info) = newState;
1123                         /* else drop finished, and info has been flushed */
1124                 }
1125
1126         } else {
1127                 wwarning("received DnD message without having a target");
1128         }
1129 }
1130
1131 void WMSetViewDragImage(WMView * view, WMPixmap * dragImage)
1132 {
1133         if (view->dragImage != NULL)
1134                 WMReleasePixmap(view->dragImage);
1135
1136         view->dragImage = WMRetainPixmap(dragImage);
1137 }
1138
1139 void WMReleaseViewDragImage(WMView * view)
1140 {
1141         if (view->dragImage != NULL)
1142                 WMReleasePixmap(view->dragImage);
1143 }
1144
1145 /* Create a drag handler, associating drag event masks with dragEventProc */
1146 void WMCreateDragHandler(WMView * view, WMEventProc * dragEventProc, void *clientData)
1147 {
1148         WMCreateEventHandler(view,
1149                              ButtonPressMask | ButtonReleaseMask | Button1MotionMask, dragEventProc, clientData);
1150 }
1151
1152 void WMDeleteDragHandler(WMView * view, WMEventProc * dragEventProc, void *clientData)
1153 {
1154         WMDeleteEventHandler(view,
1155                              ButtonPressMask | ButtonReleaseMask | Button1MotionMask, dragEventProc, clientData);
1156 }
1157
1158 /* set default drag handler for view */
1159 void WMSetViewDraggable(WMView * view, WMDragSourceProcs * dragSourceProcs, WMPixmap * dragImage)
1160 {
1161         wassertr(dragImage != NULL);
1162         view->dragImage = WMRetainPixmap(dragImage);
1163
1164         WMSetViewDragSourceProcs(view, dragSourceProcs);
1165
1166         WMCreateDragHandler(view, dragImageHandler, view);
1167 }
1168
1169 void WMUnsetViewDraggable(WMView * view)
1170 {
1171         if (view->dragSourceProcs) {
1172                 wfree(view->dragSourceProcs);
1173                 view->dragSourceProcs = NULL;
1174         }
1175
1176         WMReleaseViewDragImage(view);
1177
1178         WMDeleteDragHandler(view, dragImageHandler, view);
1179 }