////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2013-2024 The Octave Project Developers
//
// See the file COPYRIGHT.md in the top-level directory of this
// distribution or <https://octave.org/copyright/>.
//
// This file is part of Octave.
//
// Octave 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 3 of the License, or
// (at your option) any later version.
//
// Octave 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 Octave; see the file COPYING.  If not, see
// <https://www.gnu.org/licenses/>.
//
////////////////////////////////////////////////////////////////////////

/* This is the main window derived from QMainWindow for being used
   as the main window in dock widgets like the variable editor or
   the file editor
*/

#if defined (HAVE_CONFIG_H)
#  include "config.h"
#endif

#include <QDockWidget>
#include <QEvent>
#include <QMenu>

#include "dw-main-window.h"
#include "gui-preferences-sc.h"
#include "gui-settings.h"

OCTAVE_BEGIN_NAMESPACE(octave)

dw_main_window::dw_main_window (QWidget *p)
  : QMainWindow (p)
{
  gui_settings settings;

  // Adding the actions for closing the dock widgets
  m_close_action
    = add_action (nullptr, settings.icon ("window-close", false),
                  tr ("&Close"), SLOT (request_close ()), this);

  m_close_all_action
    = add_action (nullptr, settings.icon ("window-close", false),
                  tr ("Close &All"), SLOT (request_close_all ()), this);

  m_close_others_action
    = add_action (nullptr, settings.icon ("window-close", false),
                  tr ("Close &Other"), SLOT (request_close_other ()), this);

  m_switch_left_action
    = add_action (nullptr, QIcon (), tr ("Switch to &Left Widget"),
                  SLOT (request_switch_left ()), this);

  m_switch_right_action
    = add_action (nullptr, QIcon (), tr ("Switch to &Right Widget"),
                  SLOT (request_switch_right ()), this);

  // The list of actions for floating widgets
  m_actions_list << m_close_action;
  m_actions_list << m_close_others_action;
  m_actions_list << m_close_all_action;
  m_actions_list << m_switch_left_action;
  m_actions_list << m_switch_right_action;

  notice_settings ();
}

// Re-implementing the popup menu of the main window
QMenu *dw_main_window::createPopupMenu ()
{
  QList<QAction *> new_actions = QList<QAction *> ();
  new_actions.append (m_close_action);
  new_actions.append (m_close_others_action);
  new_actions.append (m_close_all_action);

  QMenu *menu = QMainWindow::createPopupMenu ();
  QList<QAction *> actions = menu->actions();

  if (actions.length () > 0)
    {
      QAction *sep = menu->insertSeparator (actions.at (0));
      menu->insertActions (sep, new_actions);
    }
  else
    menu->addActions (new_actions);

  return menu;
}

// Adding an action to the main window
QAction * dw_main_window::add_action (QMenu *menu, const QIcon& icon,
                                      const QString& text, const char *member,
                                      QWidget *receiver)
{
  QAction *a;
  QWidget *r = this;

  if (receiver != nullptr)
    r = receiver;

  if (menu)
    a = menu->addAction (icon, text, r, member);
  else
    {
      a = new QAction (icon, text, this);
      a->setEnabled (true);
      connect (a, SIGNAL (triggered ()), r, member);
    }

  addAction (a);  // important for shortcut context
  a->setShortcutContext (Qt::WidgetWithChildrenShortcut);

  return a;
}

// Update the settings
void dw_main_window::notice_settings ()
{
  gui_settings settings;

  settings.set_shortcut (m_close_action, sc_edit_file_close);
  settings.set_shortcut (m_close_all_action, sc_edit_file_close_all);
  settings.set_shortcut (m_close_others_action, sc_edit_file_close_other);

  settings.set_shortcut (m_switch_left_action, sc_edit_tabs_switch_left_tab);
  settings.set_shortcut (m_switch_right_action, sc_edit_tabs_switch_right_tab);
}

// Slots for handling actions

// Close current widget
void dw_main_window::request_close ()
{
  for (int i = 0; i < m_dw_list.length (); i++)
    {
      if (m_dw_list.at (i)->hasFocus ())
        {
          m_dw_list.at (i)->close ();
          if (i > 0)
            m_dw_list.at (i-1)->setFocus ();
          break;
        }
    }
}

// Close other widgets
void dw_main_window::request_close_other ()
{
  for (int i = m_dw_list.length () - 1; i >= 0; i--)
    {
      if (! m_dw_list.at (i)->hasFocus ())
        m_dw_list.at (i)->close ();
    }
}

// Close all widgets
void dw_main_window::request_close_all ()
{
  for (int i = m_dw_list.length () - 1; i >= 0; i--)
    m_dw_list.at (i)->close ();
}

// Switch to left widget
void dw_main_window::request_switch_left ()
{
  request_switch (-1);
}

// Switch to right widget
void dw_main_window::request_switch_right ()
{
  request_switch (1);
}

// Switch to left/right widget
void dw_main_window::request_switch (int direction)
{
  int active = -1, next;

  for (int i = m_dw_list.length () - 1; i >= 0; i--)
    {
      if (m_dw_list.at (i)->hasFocus ())
        {
          active = i;
          break;
        }
    }

  if (active == -1)
    return;

  if (direction == -1 && active == 0)
    next = m_dw_list.length () - 1;
  else if (direction == 1 && active == m_dw_list.length () - 1)
    next = 0;
  else
    next = active + direction;

  m_dw_list.at (next)->raise ();
  m_dw_list.at (next)->activateWindow ();
  m_dw_list.at (next)->setFocus ();
}

// Reimplemented Event
bool dw_main_window::event (QEvent *ev)
{
  if (ev->type () == QEvent::ChildAdded
      || ev->type () == QEvent::ChildRemoved)
    {
      // Adding or Removing a child indicates that a dock widget was
      // created or removed.
      // In all cases, the list of dock widgets has to be updated.
      m_dw_list = findChildren<QDockWidget *>();
    }

  if (ev->type () == QEvent::StyleChange)
    {
      // This might indicate un- or re-docking a widget: Make sure
      // floating widgets get a copy of our actions
      for (int i = m_dw_list.length () - 1; i >= 0; i--)
        {
          // First remove possibly existing actions
          for (int j = m_actions_list.length () - 1; j >0; j--)
            m_dw_list.at (i)->removeAction (m_actions_list.at (j));

          // Then add our actions for floating widgets
          if (m_dw_list.at (i)->isFloating ())
            m_dw_list.at (i)->addActions (m_actions_list);
        }
    }

  return QMainWindow::event (ev);
}

OCTAVE_END_NAMESPACE(octave)
