vncviewer/DesktopWindow.cxx

/* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
 * Copyright 2011 Pierre Ossman <ossman@cendio.se> for Cendio AB
 * 
 * This is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * 
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this software; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
 * USA.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <assert.h>
#include <stdio.h>
#include <string.h>

#include <rfb/LogWriter.h>
#include <rfb/CMsgWriter.h>

#include "DesktopWindow.h"
#include "OptionsDialog.h"
#include "i18n.h"
#include "parameters.h"
#include "vncviewer.h"
#include "CConn.h"
#include "Surface.h"
#include "Viewport.h"

#include <FL/Fl.H>
#include <FL/Fl_Scrollbar.H>
#include <FL/fl_draw.H>
#include <FL/x.H>

#ifdef WIN32
#include "win32.h"
#endif

#ifdef __APPLE__
#include "cocoa.h"
#endif

#define EDGE_SCROLL_SIZE 32
#define EDGE_SCROLL_SPEED 20

using namespace rfb;

static rfb::LogWriter vlog("DesktopWindow");

DesktopWindow::DesktopWindow(int w, int h, const char *name,
                             const rfb::PixelFormat& serverPF,
                             CConn* cc_)
  : Fl_Window(w, h), cc(cc_), offscreen(NULL), firstUpdate(true),
    delayedFullscreen(false), delayedDesktopSize(false)
{
  Fl_Group* group;

  // Dummy group to prevent FLTK from moving our widgets around
  group = new Fl_Group(0, 0, w, h);
  group->resizable(NULL);
  resizable(group);

  viewport = new Viewport(w, h, serverPF, cc);

  // Position will be adjusted later
  hscroll = new Fl_Scrollbar(0, 0, 0, 0);
  vscroll = new Fl_Scrollbar(0, 0, 0, 0);
  hscroll->type(FL_HORIZONTAL);
  hscroll->callback(handleScroll, this);
  vscroll->callback(handleScroll, this);

  group->end();

  callback(handleClose, this);

  setName(name);

  OptionsDialog::addCallback(handleOptions, this);

  // Hack. See below...
  Fl::event_dispatch(&fltkHandle);

  // Support for -geometry option. Note that although we do support
  // negative coordinates, we do not support -XOFF-YOFF (ie
  // coordinates relative to the right edge / bottom edge) at this
  // time.
  int geom_x = 0, geom_y = 0;
  if (strcmp(geometry, "") != 0) {
    int matched;
    matched = sscanf(geometry.getValueStr(), "+%d+%d", &geom_x, &geom_y);
    if (matched == 2) {
      force_position(1);
    } else {
      int geom_w, geom_h;
      matched = sscanf(geometry.getValueStr(), "%dx%d+%d+%d", &geom_w, &geom_h, &geom_x, &geom_y);
      switch (matched) {
      case 4:
        force_position(1);
        /* fall through */
      case 2:
        w = geom_w;
        h = geom_h;
        break;
      default:
        geom_x = geom_y = 0;
        vlog.error(_("Invalid geometry specified!"));
      }
    }
  }

#ifdef __APPLE__
  // On OS X we can do the maximize thing properly before the
  // window is showned. Other platforms handled further down...
  if (maximize) {
    int dummy;
    Fl::screen_work_area(dummy, dummy, w, h, geom_x, geom_y);
  }
#endif

  if (force_position()) {
    resize(geom_x, geom_y, w, h);
  } else {
    size(w, h);
  }

  if (fullScreen) {
    // Hack: Window managers seem to be rather crappy at respecting
    // fullscreen hints on initial windows. So on X11 we'll have to
    // wait until after we've been mapped.
#if defined(WIN32) || defined(__APPLE__)
    fullscreen_on();
#else
    delayedFullscreen = true;
#endif
  }

  show();

  // Full screen events are not sent out for a hidden window,
  // so send a fake one here to set up things properly.
  if (fullscreen_active())
    handle(FL_FULLSCREEN);

  // Unfortunately, current FLTK does not allow us to set the
  // maximized property on Windows and X11 before showing the window.
  // See STR #2083 and STR #2178
#ifndef __APPLE__
  if (maximize) {
    maximizeWindow();
  }
#endif

  // Adjust layout now that we're visible and know our final size
  repositionWidgets();

  if (delayedFullscreen) {
    // Hack: Fullscreen requests may be ignored, so we need a timeout for
    // when we should stop waiting. We also really need to wait for the
    // resize, which can come after the fullscreen event.
    Fl::add_timeout(0.5, handleFullscreenTimeout, this);
    fullscreen_on();
  }
}


DesktopWindow::~DesktopWindow()
{
  // Unregister all timeouts in case they get a change tro trigger
  // again later when this object is already gone.
  Fl::remove_timeout(handleGrab, this);
  Fl::remove_timeout(handleResizeTimeout, this);
  Fl::remove_timeout(handleFullscreenTimeout, this);
  Fl::remove_timeout(handleEdgeScroll, this);

  OptionsDialog::removeCallback(handleOptions);

  delete offscreen;

  // FLTK automatically deletes all child widgets, so we shouldn't touch
  // them ourselves here
}


const rfb::PixelFormat &DesktopWindow::getPreferredPF()
{
  return viewport->getPreferredPF();
}


void DesktopWindow::setName(const char *name)
{
  CharArray windowNameStr;
  windowNameStr.replaceBuf(new char[256]);

  snprintf(windowNameStr.buf, 256, "%.240s - TigerVNC", name);

  copy_label(windowNameStr.buf);
}


// Copy the areas of the framebuffer that have been changed (damaged)
// to the displayed window.

void DesktopWindow::updateWindow()
{
  if (firstUpdate) {
    if (cc->cp.supportsSetDesktopSize) {
      // Hack: Wait until we're in the proper mode and position until
      // resizing things, otherwise we might send the wrong thing.
      if (delayedFullscreen)
        delayedDesktopSize = true;
      else
        handleDesktopSize();
    }
    firstUpdate = false;
  }

  viewport->updateWindow();
}


void DesktopWindow::resizeFramebuffer(int new_w, int new_h)
{
  if ((new_w == viewport->w()) && (new_h == viewport->h()))
    return;

  // If we're letting the viewport match the window perfectly, then
  // keep things that way for the new size, otherwise just keep things
  // like they are.
  if (!fullscreen_active()) {
    if ((w() == viewport->w()) && (h() == viewport->h()))
      size(new_w, new_h);
    else {
      // Make sure the window isn't too big. We do this manually because
      // we have to disable the window size restriction (and it isn't
      // entirely trustworthy to begin with).
      if ((w() > new_w) || (h() > new_h))
        size(__rfbmin(w(), new_w), __rfbmin(h(), new_h));
    }
  }

  viewport->size(new_w, new_h);

  repositionWidgets();
}


void DesktopWindow::setCursor(int width, int height, const Point& hotspot,
                              void* data, void* mask)
{
  viewport->setCursor(width, height, hotspot, data, mask);
}


void DesktopWindow::draw()
{
  bool redraw;

  int X, Y, W, H;

  // X11 needs an off screen buffer for compositing to avoid flicker
#if !defined(WIN32) && !defined(__APPLE__)

  // Adjust offscreen surface dimensions
  if ((offscreen == NULL) ||
      (offscreen->width() != w()) || (offscreen->height() != h())) {
    delete offscreen;
    offscreen = new Surface(w(), h());
  }

#endif

  // Active area inside scrollbars
  W = w() - (vscroll->visible() ? vscroll->w() : 0);
  H = h() - (hscroll->visible() ? hscroll->h() : 0);

  // Full redraw?
  redraw = (damage() & ~FL_DAMAGE_CHILD);

  // Redraw background only on full redraws
  if (redraw) {
    if (offscreen)
      offscreen->clear(40, 40, 40);
    else
      fl_rectf(0, 0, W, H, 40, 40, 40);
  }

  // Make sure the viewport isn't trampling on the scrollbars
  fl_push_clip(0, 0, W, H);

  if (offscreen) {
    viewport->draw(offscreen);
    viewport->clear_damage();
  } else {
    if (redraw)
      draw_child(*viewport);
    else
      update_child(*viewport);
  }

  fl_pop_clip();

  // Flush offscreen surface to screen
  if (offscreen) {
    fl_clip_box(0, 0, W, H, X, Y, W, H);
    offscreen->draw(X, Y, X, Y, W, H);
  }

  // Finally the scrollbars

  if (redraw) {
    draw_child(*hscroll);
    draw_child(*vscroll);
  } else {
    update_child(*hscroll);
    update_child(*vscroll);
  }
}


void DesktopWindow::resize(int x, int y, int w, int h)
{
  bool resizing;

#if ! (defined(WIN32) || defined(__APPLE__))
  // X11 window managers will treat a resize to cover the entire
  // monitor as a request to go full screen. Make sure we avoid this.
  if (!fullscreen_active()) {
    bool resize_req;

    // If there is no X11 window, then this must be a resize request,
    // not a notification from the X server.
    if (!shown())
      resize_req = true;
    else {
      // Otherwise we need to get the real window coordinates to tell
      // the difference
      XWindowAttributes actual;
      Window cr;
      int wx, wy;

      XGetWindowAttributes(fl_display, fl_xid(this), &actual);
      XTranslateCoordinates(fl_display, fl_xid(this), actual.root,
                            0, 0, &wx, &wy, &cr);

      // Actual resize request?
      if ((wx != x) || (wy != y) ||
          (actual.width != w) || (actual.height != h))
        resize_req = true;
      else
        resize_req = false;
    }

    if (resize_req) {
      for (int i = 0;i < Fl::screen_count();i++) {
        int sx, sy, sw, sh;

        Fl::screen_xywh(sx, sy, sw, sh, i);

        if ((sx == x) && (sy == y) && (sw == w) && (sh == h)) {
          vlog.info(_("Adjusting window size to avoid accidental full screen request"));
          // Assume a panel of some form and adjust the height
          y += 20;
          h -= 40;
        }
      }
    }
  }
#endif

  if ((this->w() != w) || (this->h() != h))
    resizing = true;
  else
    resizing = false;

  Fl_Window::resize(x, y, w, h);

  if (resizing) {
    // Try to get the remote size to match our window size, provided
    // the following conditions are true:
    //
    // a) The user has this feature turned on
    // b) The server supports it
    // c) We're not still waiting for a chance to handle DesktopSize
    // d) We're not still waiting for startup fullscreen to kick in
    //
    if (not firstUpdate and not delayedFullscreen and
        ::remoteResize and cc->cp.supportsSetDesktopSize) {
      // We delay updating the remote desktop as we tend to get a flood
      // of resize events as the user is dragging the window.
      Fl::remove_timeout(handleResizeTimeout, this);
      Fl::add_timeout(0.5, handleResizeTimeout, this);
    }

    repositionWidgets();
  }
}


int DesktopWindow::handle(int event)
{
  switch (event) {
  case FL_FULLSCREEN:
    fullScreen.setParam(fullscreen_active());

    // Update scroll bars
    repositionWidgets();

    if (!fullscreenSystemKeys)
      break;

    if (fullscreen_active())
      grabKeyboard();
    else
      ungrabKeyboard();

    break;

  case FL_ENTER:
  case FL_LEAVE:
  case FL_DRAG:
  case FL_MOVE:
    if (fullscreen_active()) {
      if (((viewport->x() < 0) && (Fl::event_x() < EDGE_SCROLL_SIZE)) ||
          ((viewport->x() + viewport->w() > w()) && (Fl::event_x() > w() - EDGE_SCROLL_SIZE)) ||
          ((viewport->y() < 0) && (Fl::event_y() < EDGE_SCROLL_SIZE)) ||
          ((viewport->y() + viewport->h() > h()) && (Fl::event_y() > h() - EDGE_SCROLL_SIZE))) {
        if (!Fl::has_timeout(handleEdgeScroll, this))
          Fl::add_timeout(0.1, handleEdgeScroll, this);
      }
    }
    // Continue processing so that the viewport also gets mouse events
    break;
  }

  return Fl_Window::handle(event);
}


int DesktopWindow::fltkHandle(int event, Fl_Window *win)
{
  int ret;

  ret = Fl::handle_(event, win);

  // This is hackish and the result of the dodgy focus handling in FLTK.
  // The basic problem is that FLTK's view of focus and the system's tend
  // to differ, and as a result we do not see all the FL_FOCUS events we
  // need. Fortunately we can grab them here...

  DesktopWindow *dw = dynamic_cast<DesktopWindow*>(win);

  if (dw && fullscreenSystemKeys) {
    switch (event) {
    case FL_FOCUS:
      // FIXME: We reassert the keyboard grabbing on focus as FLTK there are
      //        some issues we need to work around:
      //        a) Fl::grab(0) on X11 will release the keyboard grab for us.
      //        b) Gaining focus on the system level causes FLTK to switch
      //           window level on OS X.
      if (dw->fullscreen_active())
        dw->grabKeyboard();
      break;

    case FL_UNFOCUS:
      // FIXME: We need to relinquish control when the entire window loses
      //        focus as it is very tied to this specific window on some
      //        platforms and we want to be able to open subwindows.
      dw->ungrabKeyboard();
      break;
    }
  }

  return ret;
}


void DesktopWindow::fullscreen_on()
{
  if (not fullScreenAllMonitors)
    fullscreen_screens(-1, -1, -1, -1);
  else {
    int top, bottom, left, right;
    int top_y, bottom_y, left_x, right_x;

    int sx, sy, sw, sh;

    top = bottom = left = right = 0;

    Fl::screen_xywh(sx, sy, sw, sh, 0);
    top_y = sy;
    bottom_y = sy + sh;
    left_x = sx;
    right_x = sx + sw;

    for (int i = 1;i < Fl::screen_count();i++) {
      Fl::screen_xywh(sx, sy, sw, sh, i);
      if (sy < top_y) {
        top = i;
        top_y = sy;
      }
      if ((sy + sh) > bottom_y) {
        bottom = i;
        bottom_y = sy + sh;
      }
      if (sx < left_x) {
        left = i;
        left_x = sx;
      }
      if ((sx + sw) > right_x) {
        right = i;
        right_x = sx + sw;
      }
    }

    fullscreen_screens(top, bottom, left, right);
  }

  fullscreen();
}

void DesktopWindow::grabKeyboard()
{
  // Grabbing the keyboard is fairly safe as FLTK reroutes events to the
  // correct widget regardless of which low level window got the system
  // event.

  // FIXME: Push this stuff into FLTK.

#if defined(WIN32)
  int ret;
  
  ret = win32_enable_lowlevel_keyboard(fl_xid(this));
  if (ret != 0)
    vlog.error(_("Failure grabbing keyboard"));
#elif defined(__APPLE__)
  int ret;
  
  ret = cocoa_capture_display(this, fullScreenAllMonitors);
  if (ret != 0)
    vlog.error(_("Failure grabbing keyboard"));
#else
  int ret;

  ret = XGrabKeyboard(fl_display, fl_xid(this), True,
                      GrabModeAsync, GrabModeAsync, CurrentTime);
  if (ret) {
    if (ret == AlreadyGrabbed) {
      // It seems like we can race with the WM in some cases.
      // Try again in a bit.
      if (!Fl::has_timeout(handleGrab, this))
        Fl::add_timeout(0.500, handleGrab, this);
    } else {
      vlog.error(_("Failure grabbing keyboard"));
    }
  }

  // We also need to grab the pointer as some WMs like to grab buttons
  // combined with modifies (e.g. Alt+Button0 in metacity).
  ret = XGrabPointer(fl_display, fl_xid(this), True,
                     ButtonPressMask|ButtonReleaseMask|
                     ButtonMotionMask|PointerMotionMask,
                     GrabModeAsync, GrabModeAsync,
                     None, None, CurrentTime);
  if (ret)
    vlog.error(_("Failure grabbing mouse"));
#endif
}


void DesktopWindow::ungrabKeyboard()
{
  Fl::remove_timeout(handleGrab, this);

#if defined(WIN32)
  win32_disable_lowlevel_keyboard(fl_xid(this));
#elif defined(__APPLE__)
  cocoa_release_display(this);
#else
  // FLTK has a grab so lets not mess with it
  if (Fl::grab())
    return;

  XUngrabPointer(fl_display, fl_event_time);
  XUngrabKeyboard(fl_display, fl_event_time);
#endif
}


void DesktopWindow::handleGrab(void *data)
{
  DesktopWindow *self = (DesktopWindow*)data;

  assert(self);

  if (!fullscreenSystemKeys)
    return;
  if (!self->fullscreen_active())
    return;

  self->grabKeyboard();
}


#define _NET_WM_STATE_ADD           1  /* add/set property */
void DesktopWindow::maximizeWindow()
{
#if defined(WIN32)
  // We cannot use ShowWindow() in full screen mode as it will
  // resize things implicitly. Fortunately modifying the style
  // directly results in a maximized state once we leave full screen.
  if (fullscreen_active()) {
    WINDOWINFO wi;
    wi.cbSize = sizeof(WINDOWINFO);
    GetWindowInfo(fl_xid(this), &wi);
    SetWindowLongPtr(fl_xid(this), GWL_STYLE, wi.dwStyle | WS_MAXIMIZE);
  } else
    ShowWindow(fl_xid(this), SW_MAXIMIZE);
#elif defined(__APPLE__)
  // OS X is somewhat strange and does not really have a concept of a
  // maximized window, so we can simply resize the window to the workarea.
  // Note that we shouldn't do this whilst in full screen as that will
  // incorrectly adjust things.
  if (fullscreen_active())
    return;
  int X, Y, W, H;
  Fl::screen_work_area(X, Y, W, H, this->x(), this->y());
  size(W, H);
#else
  // X11
  fl_open_display();
  Atom net_wm_state = XInternAtom (fl_display, "_NET_WM_STATE", 0);
  Atom net_wm_state_maximized_vert = XInternAtom (fl_display, "_NET_WM_STATE_MAXIMIZED_VERT", 0);
  Atom net_wm_state_maximized_horz = XInternAtom (fl_display, "_NET_WM_STATE_MAXIMIZED_HORZ", 0);

  XEvent e;
  e.xany.type = ClientMessage;
  e.xany.window = fl_xid(this);
  e.xclient.message_type = net_wm_state;
  e.xclient.format = 32;
  e.xclient.data.l[0] = _NET_WM_STATE_ADD;
  e.xclient.data.l[1] = net_wm_state_maximized_vert;
  e.xclient.data.l[2] = net_wm_state_maximized_horz;
  e.xclient.data.l[3] = 0;
  e.xclient.data.l[4] = 0;
  XSendEvent(fl_display, RootWindow(fl_display, fl_screen), 0, SubstructureNotifyMask | SubstructureRedirectMask, &e);
#endif
}


void DesktopWindow::handleDesktopSize()
{
  if (strcmp(desktopSize, "") != 0) {
    int width, height;

    // An explicit size has been requested

    if (sscanf(desktopSize, "%dx%d", &width, &height) != 2)
      return;

    remoteResize(width, height);
  } else if (::remoteResize) {
    // No explicit size, but remote resizing is on so make sure it
    // matches whatever size the window ended up being
    remoteResize(w(), h());
  }
}


void DesktopWindow::handleResizeTimeout(void *data)
{
  DesktopWindow *self = (DesktopWindow *)data;

  assert(self);

  self->remoteResize(self->w(), self->h());
}


void DesktopWindow::remoteResize(int width, int height)
{
  ScreenSet layout;
  ScreenSet::iterator iter;

  if (!fullscreen_active() || (width > w()) || (height > h())) {
    // In windowed mode (or the framebuffer is so large that we need
    // to scroll) we just report a single virtual screen that covers
    // the entire framebuffer.

    layout = cc->cp.screenLayout;

    // Not sure why we have no screens, but adding a new one should be
    // safe as there is nothing to conflict with...
    if (layout.num_screens() == 0)
      layout.add_screen(rfb::Screen());
    else if (layout.num_screens() != 1) {
      // More than one screen. Remove all but the first (which we
      // assume is the "primary").

      while (true) {
        iter = layout.begin();
        ++iter;

        if (iter == layout.end())
          break;

        layout.remove_screen(iter->id);
      }
    }

    // Resize the remaining single screen to the complete framebuffer
    layout.begin()->dimensions.tl.x = 0;
    layout.begin()->dimensions.tl.y = 0;
    layout.begin()->dimensions.br.x = width;
    layout.begin()->dimensions.br.y = height;
  } else {
    int i;
    rdr::U32 id;
    int sx, sy, sw, sh;
    Rect viewport_rect, screen_rect;

    // In full screen we report all screens that are fully covered.

    viewport_rect.setXYWH(x() + (w() - width)/2, y() + (h() - height)/2,
                          width, height);

    // If we can find a matching screen in the existing set, we use
    // that, otherwise we create a brand new screen.
    //
    // FIXME: We should really track screens better so we can handle
    //        a resized one.
    //
    for (i = 0;i < Fl::screen_count();i++) {
      Fl::screen_xywh(sx, sy, sw, sh, i);

      // Check that the screen is fully inside the framebuffer
      screen_rect.setXYWH(sx, sy, sw, sh);
      if (!screen_rect.enclosed_by(viewport_rect))
        continue;

      // Adjust the coordinates so they are relative to our viewport
      sx -= viewport_rect.tl.x;
      sy -= viewport_rect.tl.y;

      // Look for perfectly matching existing screen...
      for (iter = cc->cp.screenLayout.begin();
           iter != cc->cp.screenLayout.end(); ++iter) {
        if ((iter->dimensions.tl.x == sx) &&
            (iter->dimensions.tl.y == sy) &&
            (iter->dimensions.width() == sw) &&
            (iter->dimensions.height() == sh))
          break;
      }

      // Found it?
      if (iter != cc->cp.screenLayout.end()) {
        layout.add_screen(*iter);
        continue;
      }

      // Need to add a new one, which means we need to find an unused id
      while (true) {
        id = rand();
        for (iter = cc->cp.screenLayout.begin();
             iter != cc->cp.screenLayout.end(); ++iter) {
          if (iter->id == id)
            break;
        }

        if (iter == cc->cp.screenLayout.end())
          break;
      }

      layout.add_screen(rfb::Screen(id, sx, sy, sw, sh, 0));
    }

    // If the viewport doesn't match a physical screen, then we might
    // end up with no screens in the layout. Add a fake one...
    if (layout.num_screens() == 0)
      layout.add_screen(rfb::Screen(0, 0, 0, width, height, 0));
  }

  // Do we actually change anything?
  if ((width == cc->cp.width) &&
      (height == cc->cp.height) &&
      (layout == cc->cp.screenLayout))
    return;

  char buffer[2048];
  vlog.debug("Requesting framebuffer resize from %dx%d to %dx%d",
             cc->cp.width, cc->cp.height, width, height);
  layout.print(buffer, sizeof(buffer));
  vlog.debug("%s", buffer);

  if (!layout.validate(width, height)) {
    vlog.error(_("Invalid screen layout computed for resize request!"));
    return;
  }

  cc->writer()->writeSetDesktopSize(width, height, layout);
}


void DesktopWindow::repositionWidgets()
{
  int new_x, new_y;

  // Viewport position

  new_x = viewport->x();
  new_y = viewport->y();

  if (w() > viewport->w())
    new_x = (w() - viewport->w()) / 2;
  else {
    if (viewport->x() > 0)
      new_x = 0;
    else if (w() > (viewport->x() + viewport->w()))
      new_x = w() - viewport->w();
  }

  // Same thing for y axis
  if (h() > viewport->h())
    new_y = (h() - viewport->h()) / 2;
  else {
    if (viewport->y() > 0)
      new_y = 0;
    else if (h() > (viewport->y() + viewport->h()))
      new_y = h() - viewport->h();
  }

  if ((new_x != viewport->x()) || (new_y != viewport->y())) {
    viewport->position(new_x, new_y);
    damage(FL_DAMAGE_SCROLL);
  }

  // Scrollbars visbility

  if (!fullscreen_active() && (w() < viewport->w()))
    hscroll->show();
  else
    hscroll->hide();

  if (!fullscreen_active() && (h() < viewport->h()))
    vscroll->show();
  else
    vscroll->hide();

  // Scrollbars positions

  hscroll->resize(0, h() - Fl::scrollbar_size(),
                  w() - (vscroll->visible() ? Fl::scrollbar_size() : 0),
                  Fl::scrollbar_size());
  vscroll->resize(w() - Fl::scrollbar_size(), 0,
                  Fl::scrollbar_size(),
                  h() - (hscroll->visible() ? Fl::scrollbar_size() : 0));

  // Scrollbars range

  hscroll->value(-viewport->x(),
                 w() - (vscroll->visible() ? vscroll->w() : 0),
                 0, viewport->w());
  vscroll->value(-viewport->y(),
                 h() - (hscroll->visible() ? hscroll->h() : 0),
                 0, viewport->h());
  hscroll->value(hscroll->clamp(hscroll->value()));
  vscroll->value(vscroll->clamp(vscroll->value()));
}

void DesktopWindow::handleClose(Fl_Widget *wnd, void *data)
{
  exit_vncviewer();
}


void DesktopWindow::handleOptions(void *data)
{
  DesktopWindow *self = (DesktopWindow*)data;

  if (self->fullscreen_active() && fullscreenSystemKeys)
    self->grabKeyboard();
  else
    self->ungrabKeyboard();

  if (fullScreen && !self->fullscreen_active())
    self->fullscreen_on();
  else if (!fullScreen && self->fullscreen_active())
    self->fullscreen_off();
}

void DesktopWindow::handleFullscreenTimeout(void *data)
{
  DesktopWindow *self = (DesktopWindow *)data;

  assert(self);

  self->delayedFullscreen = false;

  if (self->delayedDesktopSize) {
    self->handleDesktopSize();
    self->delayedDesktopSize = false;
  }
}

void DesktopWindow::scrollTo(int x, int y)
{
  x = hscroll->clamp(x);
  y = vscroll->clamp(y);

  hscroll->value(x);
  vscroll->value(y);

  if (!hscroll->visible())
    x = -viewport->x();
  if (!vscroll->visible())
    y = -viewport->y();

  // Scrollbar position results in inverse movement of
  // the viewport widget
  x = -x;
  y = -y;

  if ((viewport->x() == x) && (viewport->y() == y))
    return;

  viewport->position(x, y);
  damage(FL_DAMAGE_SCROLL);
}

void DesktopWindow::handleScroll(Fl_Widget *widget, void *data)
{
  DesktopWindow *self = (DesktopWindow *)data;

  self->scrollTo(self->hscroll->value(), self->vscroll->value());
}

void DesktopWindow::handleEdgeScroll(void *data)
{
  DesktopWindow *self = (DesktopWindow *)data;

  int mx, my;
  int dx, dy;

  assert(self);

  if (!self->fullscreen_active())
    return;

  mx = Fl::event_x();
  my = Fl::event_y();

  dx = dy = 0;

  // Clamp mouse position in case it is outside the window
  if (mx < 0)
    mx = 0;
  if (mx > self->w())
    mx = self->w();
  if (my < 0)
    my = 0;
  if (my > self->h())
    my = self->h();

  if ((self->viewport->x() < 0) && (mx < EDGE_SCROLL_SIZE))
    dx = EDGE_SCROLL_SPEED -
         EDGE_SCROLL_SPEED * mx / EDGE_SCROLL_SIZE;
  if ((self->viewport->x() + self->viewport->w() > self->w()) &&
      (mx > self->w() - EDGE_SCROLL_SIZE))
    dx = EDGE_SCROLL_SPEED * (self->w() - mx) / EDGE_SCROLL_SIZE -
         EDGE_SCROLL_SPEED;
  if ((self->viewport->y() < 0) && (my < EDGE_SCROLL_SIZE))
    dy = EDGE_SCROLL_SPEED -
         EDGE_SCROLL_SPEED * my / EDGE_SCROLL_SIZE;
  if ((self->viewport->y() + self->viewport->h() > self->h()) &&
      (my > self->h() - EDGE_SCROLL_SIZE))
    dy = EDGE_SCROLL_SPEED * (self->h() - my) / EDGE_SCROLL_SIZE -
         EDGE_SCROLL_SPEED;

  if ((dx == 0) && (dy == 0))
    return;

  self->scrollTo(self->hscroll->value() + dx, self->vscroll->value() + dy);

  Fl::repeat_timeout(0.1, handleEdgeScroll, data);
}