/*
  QtCurve (C) Craig Drummond, 2007 - 2010 craig.p.drummond@gmail.com

  ----

  This program is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public
  License version 2 as published by the Free Software Foundation.

  This program 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 program; see the file COPYING.  If not, write to
  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  Boston, MA 02110-1301, USA.
*/

#include "shortcuthandler.h"
#include <qpopupmenu.h>
#include <qapplication.h>
#include <qobjectlist.h>
#include <qmainwindow.h>
#include <qdialog.h>
#include <qstyle.h>

ShortcutHandler::ShortcutHandler(QObject *parent)
  : QObject(parent)
  , itsAltDown(false)
{
}

ShortcutHandler::~ShortcutHandler()
{
}

bool ShortcutHandler::hasSeenAlt(const QWidget *widget) const
{
  if (widget && !widget->isEnabled())
    return false;

  if (::qt_cast<const QPopupMenu *>(widget))
    return itsOpenMenus.count() && itsOpenMenus.last() == widget;
  //     {
  //         const QWidget *w=widget;
  //
  //         while(w)
  //         {
  //             if(itsSeenAlt.contains((QWidget *)w))
  //                 return true;
  //             w=w->parentWidget();
  //         }
  //     }
  else
    return itsOpenMenus.isEmpty() &&  itsSeenAlt.contains((QWidget *)(widget->topLevelWidget()));
  return false;
}

bool ShortcutHandler::showShortcut(const QWidget *widget) const
{
  return itsAltDown && hasSeenAlt(widget);
}

void ShortcutHandler::widgetDestroyed(QObject *o)
{
  itsUpdated.remove(static_cast<QWidget *>(o));
  itsOpenMenus.remove(static_cast<QWidget *>(o));
}

void ShortcutHandler::updateWidget(QWidget *w)
{
  if (!itsUpdated.contains(w)) {
    connect(w, SIGNAL(destroyed(QObject *)), this, SLOT(widgetDestroyed(QObject *)));
    itsUpdated.append(w);
    w->repaint(TRUE);
  }
}

void ShortcutHandler::setSeenAlt(QWidget *w)
{
  if (!itsSeenAlt.contains(w))
    itsSeenAlt.append(w);
}

bool ShortcutHandler::eventFilter(QObject *o, QEvent *e)
{
  if (!o->isWidgetType())
    return QObject::eventFilter(o, e);

  QWidget *widget = ::qt_cast<QWidget *>(o);
  switch (e->type()) {
    case QEvent::KeyPress:
      if (Key_Alt == ((QKeyEvent *)e)->key()) {
        itsAltDown = true;

        if (::qt_cast<QPopupMenu *>(widget)) {
          setSeenAlt(widget);
          updateWidget(widget);
          if (widget->parentWidget() && widget->parentWidget()->topLevelWidget())
            itsSeenAlt.append(widget->parentWidget()->topLevelWidget());
        } else {
          widget = widget->topLevelWidget();
          setSeenAlt(widget);

          // Alt has been pressed - find all widgets that care
          QObjectList *l = widget->queryList("QWidget");
          QObjectListIt it(*l);
          QWidget *w;
          while ((w = (QWidget *)it.current()) != 0) {
            ++it;
            if (!(w->isTopLevel() || !w->isVisible())) // || w->style().styleHint(QStyle::SH_UnderlineAccelerator, w)))
              updateWidget(w);
          }
          delete l;
        }
      }
      break;
    case QEvent::WindowDeactivate:
    case QEvent::KeyRelease:
      if (QEvent::WindowDeactivate == e->type() || Key_Alt == static_cast<QKeyEvent *>(e)->key()) {
        itsAltDown = false;
        QValueList<QWidget *>::const_iterator it(itsUpdated.begin()),
                   end(itsUpdated.end());

        for (; it != end; ++it)
          (*it)->repaint(TRUE);
        if (!itsUpdated.contains(widget))
          widget->repaint(TRUE);
        itsSeenAlt.clear();
        itsUpdated.clear();
      }
      break;
    case QEvent::Show:
      if (::qt_cast<QPopupMenu *>(widget)) {
        QWidget *prev = itsOpenMenus.count() ? itsOpenMenus.last() : 0L;
        itsOpenMenus.append(widget);
        if (itsAltDown && prev)
          prev->repaint(TRUE);
        connect(widget, SIGNAL(destroyed(QObject *)), this, SLOT(widgetDestroyed(QObject *)));
      }
      break;
    case QEvent::Hide:
      if (::qt_cast<QPopupMenu *>(widget)) {
        itsSeenAlt.remove(widget);
        itsUpdated.remove(widget);
        itsOpenMenus.remove(widget);
        if (itsAltDown) {
          if (itsOpenMenus.count())
            itsOpenMenus.last()->repaint(TRUE);
          else if (widget->parentWidget() && widget->parentWidget()->topLevelWidget())
            widget->parentWidget()->topLevelWidget()->repaint(TRUE);
        }
      }
      break;
    case QEvent::Close:
      // Reset widget when closing
      itsSeenAlt.remove(widget);
      itsUpdated.remove(widget);
      itsSeenAlt.remove(widget->topLevelWidget());
      itsOpenMenus.remove(widget);
      if (itsAltDown && itsOpenMenus.count())
        itsOpenMenus.last()->repaint(TRUE);
      break;
    default:
      break;
  }
  return QObject::eventFilter(o, e);
}

//#include "shortcuthandler.moc"