////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2011-2022 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/>.
//
////////////////////////////////////////////////////////////////////////

// Programming Note: this file has many lines longer than 80 characters
// due to long function, variable, and property names.  Please don't
// break those lines as it tends to make this code even harder to read.

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

#include <QButtonGroup>
#include <QDir>
#include <QFileDialog>
#include <QFileInfo>
#include <QHash>
#include <QMessageBox>
#include <QScrollBar>
#include <QStyleFactory>
#include <QTextCodec>
#include <QVector>

#if defined (HAVE_QSCINTILLA)
#  include "octave-qscintilla.h"
#  include "octave-txt-lexer.h"
#  include <QScrollArea>

#  if defined (HAVE_QSCI_QSCILEXEROCTAVE_H)
#    define HAVE_LEXER_OCTAVE 1
#    include <Qsci/qscilexeroctave.h>
#  elif defined (HAVE_QSCI_QSCILEXERMATLAB_H)
#    define HAVE_LEXER_MATLAB 1
#    include <Qsci/qscilexermatlab.h>
#  endif

#  include <Qsci/qscilexercpp.h>
#  include <Qsci/qscilexerjava.h>
#  include <Qsci/qscilexerbash.h>
#  include <Qsci/qscilexerperl.h>
#  include <Qsci/qscilexerbatch.h>
#  include <Qsci/qscilexerdiff.h>
#endif

#include "gui-preferences-all.h"
#include "octave-qobject.h"
#include "octave-qtutils.h"
#include "settings-dialog.h"
#include "variable-editor.h"
#include "workspace-model.h"

OCTAVE_BEGIN_NAMESPACE(octave)

  settings_dialog::settings_dialog (QWidget *p, base_qobject& oct_qobj,
                                    const QString& desired_tab)
    : QDialog (p), Ui::settings_dialog (), m_octave_qobj (oct_qobj)
  {
    setupUi (this);

    gui_settings settings;

    // look for available language files and the actual settings
    resource_manager& rmgr = m_octave_qobj.get_resource_manager ();
    QString qm_dir_name = rmgr.get_gui_translation_dir ();

    QDir qm_dir (qm_dir_name);
    QFileInfoList qm_files = qm_dir.entryInfoList (QStringList ("*.qm"),
                             QDir::Files | QDir::Readable, QDir::Name);

    for (int i = 0; i < qm_files.length (); i++)   // insert available languages
      comboBox_language->addItem (qm_files.at (i).baseName ());
    // System at beginning
    comboBox_language->insertItem (0, tr ("System setting"));
    comboBox_language->insertSeparator (1);    // separator after System
    QString language = settings.value (global_language.key,
                                        global_language.def).toString ();
    if (language == global_language.def.toString ())
      language = tr ("System setting");
    int selected = comboBox_language->findText (language);
    if (selected >= 0)
      comboBox_language->setCurrentIndex (selected);
    else
      comboBox_language->setCurrentIndex (0);  // System is default

    // Global style
    QStringList styles = QStyleFactory::keys();
    styles.append (global_extra_styles);
    combo_styles->addItems (styles);
    combo_styles->insertItem (0, global_style.def.toString ());
    combo_styles->insertSeparator (1);
    QString current_style = settings.value (global_style).toString ();
    if (current_style == global_style.def.toString ())
      current_style = global_style.def.toString ();
    selected = combo_styles->findText (current_style);
    if (selected >= 0)
      combo_styles->setCurrentIndex (selected);
    else
      combo_styles->setCurrentIndex (0);

    // icon size and theme
    QButtonGroup *icon_size_group = new QButtonGroup (this);
    icon_size_group->addButton (icon_size_small);
    icon_size_group->addButton (icon_size_normal);
    icon_size_group->addButton (icon_size_large);
    int icon_size = settings.value (global_icon_size).toInt ();
    icon_size_normal->setChecked (true);  // the default
    icon_size_small->setChecked (icon_size < 0);
    icon_size_large->setChecked (icon_size > 0);
    combo_box_icon_theme->addItems (global_all_icon_theme_names);
    int theme = settings.value (global_icon_theme_index.key).toInt ();
    combo_box_icon_theme->setCurrentIndex (theme);

    // which icon has to be selected
    QButtonGroup *icon_group = new QButtonGroup (this);
    icon_group->addButton (general_icon_octave);
    icon_group->addButton (general_icon_graphic);
    icon_group->addButton (general_icon_letter);
    QString widget_icon_set =
      settings.value (dw_icon_set).toString ();
    general_icon_octave->setChecked (true);  // the default (if invalid set)
    general_icon_octave->setChecked (widget_icon_set == "NONE");
    general_icon_graphic->setChecked (widget_icon_set == "GRAPHIC");
    general_icon_letter->setChecked (widget_icon_set == "LETTER");

    // custom title bar of dock widget
    QColor bg_color = settings.value (dw_title_bg_color).value<QColor> ();
    m_widget_title_bg_color = new color_picker (bg_color);
    m_widget_title_bg_color->setEnabled (false);
    layout_widget_bgtitle->addWidget (m_widget_title_bg_color, 0);

    connect (cb_widget_custom_style, &QCheckBox::toggled,
             m_widget_title_bg_color, &color_picker::setEnabled);

    QColor bg_color_active = settings.value (dw_title_bg_color_active).value<QColor> ();
    m_widget_title_bg_color_active = new color_picker (bg_color_active);
    m_widget_title_bg_color_active->setEnabled (false);
    layout_widget_bgtitle_active->addWidget (m_widget_title_bg_color_active, 0);

    connect (cb_widget_custom_style, &QCheckBox::toggled,
             m_widget_title_bg_color_active, &color_picker::setEnabled);

    QColor fg_color = settings.value (dw_title_fg_color).value<QColor> ();
    m_widget_title_fg_color = new color_picker (fg_color);
    m_widget_title_fg_color->setEnabled (false);
    layout_widget_fgtitle->addWidget (m_widget_title_fg_color, 0);

    connect (cb_widget_custom_style, &QCheckBox::toggled,
             m_widget_title_fg_color, &color_picker::setEnabled);

    QColor fg_color_active = settings.value (dw_title_fg_color_active).value<QColor> ();
    m_widget_title_fg_color_active = new color_picker (fg_color_active);
    m_widget_title_fg_color_active->setEnabled (false);
    layout_widget_fgtitle_active->addWidget (m_widget_title_fg_color_active, 0);

    connect (cb_widget_custom_style, &QCheckBox::toggled,
             m_widget_title_fg_color_active, &color_picker::setEnabled);

    sb_3d_title->setValue (settings.value (dw_title_3d.key,
                                            dw_title_3d.def).toInt ());
    cb_widget_custom_style->setChecked (settings.value (dw_title_custom_style).toBool ());

    // Native file dialogs.
    // FIXME: This preference can be deprecated / removed if all display
    //       managers, especially KDE, run those dialogs without hangs or
    //       delays from the start (bug #54607).
    cb_use_native_file_dialogs->setChecked (settings.value (global_use_native_dialogs).toBool ());

    // Cursor blinking: consider old terminal related setting if not yet set
    // FIXME: This pref. can be deprecated / removed if Qt adds support for
    //       getting the cursor blink preferences from all OS environments
    if (settings.contains (global_cursor_blinking.key))
      {
        // Preference exists, read its value
        cb_cursor_blinking->setChecked (settings.value
            (global_cursor_blinking.key, global_cursor_blinking.def).toBool ());
      }
    else
      {
        // Pref. does not exist, so take old terminal related pref.
        cb_cursor_blinking->setChecked (settings.value
                    (cs_cursor_blinking.key, cs_cursor_blinking.def).toBool ());
      }

    // focus follows mouse
    cb_focus_follows_mouse->setChecked (
      settings.value (dw_focus_follows_mouse).toBool ());

    // prompt on exit
    cb_prompt_to_exit->setChecked (
      settings.value (global_prompt_to_exit.key, global_prompt_to_exit.def).toBool ());

    // Main status bar
    cb_status_bar->setChecked (
      settings.value (global_status_bar.key, global_status_bar.def).toBool ());

    // Octave startup
    cb_restore_octave_dir->setChecked (
      settings.value (global_restore_ov_dir.key, global_restore_ov_dir.def).toBool ());
    le_octave_dir->setText (settings.value (global_ov_startup_dir.key,
                                             global_ov_startup_dir.def).toString ());

    connect (pb_octave_dir, &QPushButton::pressed,
             this, &settings_dialog::get_octave_dir);

    //
    // editor
    //
    useCustomFileEditor->setChecked (
      settings.value (global_use_custom_editor.key, global_use_custom_editor.def).toBool ());
    customFileEditor->setText (
      settings.value (global_custom_editor.key, global_custom_editor.def).toString ());
    editor_showLineNumbers->setChecked (settings.value (ed_show_line_numbers).toBool ());
    editor_linenr_size->setValue (settings.value (ed_line_numbers_size).toInt ());

    rmgr.combo_encoding (editor_combo_encoding);

    editor_highlightCurrentLine->setChecked (settings.value (ed_highlight_current_line).toBool ());
    editor_long_line_marker->setChecked (settings.value (ed_long_line_marker).toBool ());
    bool long_line =
      settings.value (ed_long_line_marker_line).toBool ();
    editor_long_line_marker_line->setChecked (long_line);
    bool long_back =
      settings.value (ed_long_line_marker_background).toBool ();
    editor_long_line_marker_background->setChecked (long_back);
    if (! (long_line || long_back))
      editor_long_line_marker_line->setChecked (true);
    editor_long_line_column->setValue (settings.value (ed_long_line_column).toInt ());
    editor_break_checkbox->setChecked (settings.value (ed_break_lines).toBool ());
    editor_break_comments_checkbox->setChecked (settings.value (ed_break_lines_comments).toBool ());
    editor_wrap_checkbox->setChecked (settings.value (ed_wrap_lines).toBool ());
    cb_edit_status_bar->setChecked (settings.value (ed_show_edit_status_bar).toBool ());
    cb_edit_tool_bar->setChecked (settings.value (ed_show_toolbar).toBool ());
    cb_code_folding->setChecked (settings.value (ed_code_folding).toBool ());
    editor_highlight_all_occurrences->setChecked (settings.value (ed_highlight_all_occurrences).toBool ());

    editor_auto_endif->setCurrentIndex (settings.value (ed_auto_endif).toInt () );
    editor_codeCompletion->setChecked (settings.value (ed_code_completion).toBool ());
    editor_spinbox_ac_threshold->setValue (settings.value (ed_code_completion_threshold).toInt ());
    editor_checkbox_ac_keywords->setChecked (settings.value (ed_code_completion_keywords).toBool ());
    editor_checkbox_ac_builtins->setEnabled (editor_checkbox_ac_keywords->isChecked ());
    editor_checkbox_ac_functions->setEnabled (editor_checkbox_ac_keywords->isChecked ());
    editor_checkbox_ac_builtins->setChecked (settings.value (ed_code_completion_octave_builtins).toBool ());
    editor_checkbox_ac_functions->setChecked (settings.value (ed_code_completion_octave_functions).toBool ());
    editor_checkbox_ac_document->setChecked (settings.value (ed_code_completion_document).toBool ());
    editor_checkbox_ac_case->setChecked (settings.value (ed_code_completion_case).toBool ());
    editor_checkbox_ac_replace->setChecked (settings.value (ed_code_completion_replace).toBool ());
    editor_ws_checkbox->setChecked (settings.value (ed_show_white_space).toBool ());
    editor_ws_indent_checkbox->setChecked (settings.value (ed_show_white_space_indent).toBool ());
    cb_show_eol->setChecked (settings.value (ed_show_eol_chars).toBool ());
    cb_show_hscrollbar->setChecked (settings.value (ed_show_hscroll_bar).toBool ());

    for (int i = 0; i < ed_tab_position_names.length (); i++)
      editor_combox_tab_pos->insertItem (i,
              tr (ed_tab_position_names.at (i).toStdString ().data ()));
    editor_combox_tab_pos->setCurrentIndex
      (settings.value (ed_tab_position).toInt ());

    editor_cb_tabs_rotated->setChecked (settings.value (ed_tabs_rotated).toBool ());
    editor_sb_tabs_max_width->setValue (settings.value (ed_tabs_max_width).toInt ());

    int selected_comment_string, selected_uncomment_string;

    if (settings.contains (ed_comment_str.key))   // new version (radio buttons)
      selected_comment_string = settings.value (ed_comment_str).toInt ();
    else                                         // old version (combo box)
      selected_comment_string = settings.value (ed_comment_str_old.key,                                                 ed_comment_str.def).toInt ();

    selected_uncomment_string = settings.value (ed_uncomment_str).toInt ();

    for (int i = 0; i < ed_comment_strings_count; i++)
      {
        m_rb_comment_strings[i] = new QRadioButton ();
        m_rb_uncomment_strings[i] = new QCheckBox ();

        connect (m_rb_comment_strings[i], &QRadioButton::clicked,
                 m_rb_uncomment_strings[i], &QCheckBox::setChecked);
        connect (m_rb_comment_strings[i], &QRadioButton::toggled,
                 m_rb_uncomment_strings[i], &QCheckBox::setDisabled);

        m_rb_comment_strings[i]->setText (ed_comment_strings.at(i));
        m_rb_comment_strings[i]->setChecked (i == selected_comment_string);
        layout_comment_strings->addWidget (m_rb_comment_strings[i]);

        m_rb_uncomment_strings[i]->setText (ed_comment_strings.at(i));
        m_rb_uncomment_strings[i]->setAutoExclusive (false);
        m_rb_uncomment_strings[i]->setChecked ( 1 << i & selected_uncomment_string);
        layout_uncomment_strings->addWidget (m_rb_uncomment_strings[i]);
      }

    combo_eol_mode->setCurrentIndex (settings.value (ed_default_eol_mode).toInt ());
    editor_auto_ind_checkbox->setChecked (settings.value (ed_auto_indent).toBool ());
    editor_tab_ind_checkbox->setChecked (settings.value (ed_tab_indents_line).toBool ());
    editor_bs_unind_checkbox->setChecked (settings.value (ed_backspace_unindents_line).toBool ());
    editor_ind_guides_checkbox->setChecked (settings.value (ed_show_indent_guides).toBool ());
    editor_ind_width_spinbox->setValue (settings.value (ed_indent_width).toInt ());
    editor_ind_uses_tabs_checkbox->setChecked (settings.value (ed_indent_uses_tabs).toBool ());
    editor_tab_width_spinbox->setValue (settings.value (ed_tab_width).toInt ());
    editor_restoreSession->setChecked (settings.value (ed_restore_session).toBool ());
    editor_create_new_file->setChecked (settings.value (ed_create_new_file).toBool ());
    editor_reload_changed_files->setChecked (settings.value (ed_always_reload_changed_files).toBool ());
    editor_force_newline->setChecked (settings.value (ed_force_newline).toBool ());
    editor_remove_trailing_spaces->setChecked (settings.value (ed_rm_trailing_spaces).toBool ());
    editor_hiding_closes_files->setChecked (settings.value (ed_hiding_closes_files).toBool ());
    editor_show_dbg_file->setChecked (settings.value (ed_show_dbg_file).toBool ());

    // terminal
    QString default_font = settings.value (global_mono_font).toString ();
    terminal_fontName->setCurrentFont (QFont (settings.value (cs_font.key, default_font).toString ()));
    terminal_fontSize->setValue (settings.value (cs_font_size).toInt ());
    terminal_history_buffer->setValue (settings.value (cs_hist_buffer).toInt ());
    terminal_cursorUseForegroundColor->setChecked (settings.value (cs_cursor_use_fgcol).toBool ());
    terminal_focus_command->setChecked (settings.value (cs_focus_cmd).toBool ());
    terminal_print_dbg_location->setChecked (settings.value (cs_dbg_location).toBool ());

    QString cursor_type
      = settings.value (cs_cursor).toString ();

    QStringList items;
    items << QString ("0") << QString ("1") << QString ("2");
    terminal_cursorType->addItems (items);
    terminal_cursorType->setItemText (0, tr ("IBeam Cursor"));
    terminal_cursorType->setItemText (1, tr ("Block Cursor"));
    terminal_cursorType->setItemText (2, tr ("Underline Cursor"));

    for (unsigned int i = 0; i < cs_cursor_types.size (); i++)
      {
        if (cursor_type.toStdString () == cs_cursor_types[i])
          {
            terminal_cursorType->setCurrentIndex (i);
            break;
          }
      }

    read_terminal_colors ();

    // file browser
    connect (sync_octave_directory, &QCheckBox::toggled,
             this, &settings_dialog::set_disabled_pref_file_browser_dir);

    sync_octave_directory->setChecked (settings.value (fb_sync_octdir).toBool ());
    cb_restore_file_browser_dir->setChecked (settings.value (fb_restore_last_dir).toBool ());
    le_file_browser_dir->setText (settings.value (fb_startup_dir.key).toString ());

    connect (pb_file_browser_dir, &QPushButton::pressed,
             this, &settings_dialog::get_file_browser_dir);

    le_file_browser_extensions->setText (settings.value (fb_txt_file_ext).toString ());

    checkbox_allow_web_connect->setChecked (settings.value (nr_allow_connection).toBool ());

    // Proxy
    bool use_proxy = settings.value (global_use_proxy.key, global_use_proxy.def).toBool ();
    use_proxy_server->setChecked (use_proxy);
    // Fill combo box and activate current one
    QString proxy_type_string = settings.value (global_proxy_type.key, global_proxy_type.def).toString ();
    proxy_type->addItems (global_proxy_all_types);
    for (int i = 0; i < global_proxy_all_types.length (); i++)
      {
        if (proxy_type->itemText (i) == proxy_type_string)
          {
            proxy_type->setCurrentIndex (i);
            break;
          }
      }
    // Fill all line edits
    proxy_host_name->setText (settings.value (global_proxy_host.key, global_proxy_host.def).toString ());
    proxy_port->setText (settings.value (global_proxy_port.key, global_proxy_port.def).toString ());
    proxy_username->setText (settings.value (global_proxy_user.key, global_proxy_user.def).toString ());
    proxy_password->setText (settings.value (global_proxy_pass.key, global_proxy_pass.def).toString ());
    // Connect relevant signals for dis-/enabling some elements
    connect (proxy_type, QOverload<int>::of (&QComboBox::currentIndexChanged),
             this, &settings_dialog::proxy_items_update);
    connect (use_proxy_server, &QCheckBox::toggled,
             this, &settings_dialog::proxy_items_update);
    // Check whehter line edits have to be enabled
    proxy_items_update ();

    // Workspace
    read_workspace_colors ();

    // variable editor
    varedit_columnWidth->setValue (settings.value (ve_column_width).toInt ());
    varedit_rowHeight->setValue (settings.value (ve_row_height).toInt ());

    varedit_font->setCurrentFont (QFont (settings.value (ve_font_name.key,
                                                          settings.value (cs_font.key, default_font)).toString ()));
    varedit_fontSize->setValue (settings.value (ve_font_size).toInt ());
    connect (varedit_useTerminalFont, &QCheckBox::toggled,
             varedit_font, &QFontComboBox::setDisabled);
    connect (varedit_useTerminalFont, &QCheckBox::toggled,
             varedit_fontSize, &QSpinBox::setDisabled);
    varedit_useTerminalFont->setChecked (settings.value (ve_use_terminal_font).toBool ());
    varedit_font->setDisabled (varedit_useTerminalFont->isChecked ());
    varedit_fontSize->setDisabled (varedit_useTerminalFont->isChecked ());

    varedit_alternate->setChecked (settings.value (ve_alternate_rows).toBool ());

    // variable editor colors
    read_varedit_colors ();

    // shortcuts

    shortcut_manager& scmgr = m_octave_qobj.get_shortcut_manager ();

    cb_prevent_readline_conflicts->setChecked (
          settings.value (sc_prevent_rl_conflicts.key,
                           sc_prevent_rl_conflicts.def).toBool ());
    cb_prevent_readline_conflicts_menu->setChecked (
          settings.value (sc_prevent_rl_conflicts_menu.key,
                           sc_prevent_rl_conflicts_menu.def).toBool ());

    // initialize the tree view with all shortcut data
    scmgr.fill_treewidget (shortcuts_treewidget);

    // connect the buttons for import/export of the shortcut sets
    connect (btn_import_shortcut_set, &QPushButton::clicked,
             this, &settings_dialog::import_shortcut_set);

    connect (btn_export_shortcut_set, &QPushButton::clicked,
             this, &settings_dialog::export_shortcut_set);

    connect (btn_default_shortcut_set, &QPushButton::clicked,
             this, &settings_dialog::default_shortcut_set);

#if defined (HAVE_QSCINTILLA)

    int mode = settings.value (ed_color_mode).toInt ();

    QCheckBox *cb_color_mode = new QCheckBox (tr (settings_color_modes.toStdString ().data ()),
                                              group_box_editor_styles);
    cb_color_mode->setToolTip (tr (settings_color_modes_tooltip.toStdString ().data ()));
    cb_color_mode->setChecked (mode > 0);
    cb_color_mode->setObjectName (ed_color_mode.key);

    QPushButton *pb_reload_default_colors = new QPushButton (tr (settings_reload_styles.toStdString ().data ()));
    pb_reload_default_colors->setToolTip (tr (settings_reload_styles_tooltip.toStdString ().data ()));

    color_picker *current_line_color = new color_picker (
      settings.value (ed_highlight_current_line_color.key +
                       settings_color_modes_ext[mode],
                       ed_highlight_current_line_color.def).value<QColor> (), this);
    current_line_color->setObjectName (ed_highlight_current_line_color.key);
    QLabel *current_line_color_label = new QLabel(
      tr ("Color of highlighted current line (magenta (255,0,255) for automatic color)")
    );

    QHBoxLayout *color_mode = new QHBoxLayout ();
    color_mode->addWidget (cb_color_mode);
    color_mode->addItem (new QSpacerItem (5, 5, QSizePolicy::Expanding));
    color_mode->addWidget (pb_reload_default_colors);

    QHBoxLayout *current_line = new QHBoxLayout ();
    current_line->addWidget (current_line_color_label);
    current_line->addWidget (current_line_color);
    current_line->addItem (new QSpacerItem (5, 5, QSizePolicy::Expanding));

    editor_styles_layout->addLayout (color_mode);
    editor_styles_layout->addLayout (current_line);

    // update colors depending on second theme selection
    connect (cb_color_mode, &QCheckBox::stateChanged,
             this, &settings_dialog::update_editor_lexers);
    connect (pb_reload_default_colors, &QPushButton::clicked,
             [=] () { update_editor_lexers (settings_reload_default_colors_flag); });

    // finally read the lexer colors using the update slot
    update_editor_lexers ();

#endif

    // which tab is the desired one?
    show_tab (desired_tab);

    // connect button box signal
    connect (button_box, &QDialogButtonBox::clicked,
             this, &settings_dialog::button_clicked);

    // restore last geometry
    if (settings.contains (sd_geometry.key))
      restoreGeometry (settings.value (sd_geometry).toByteArray ());
    else
      setGeometry (QRect (10, 50, 1000, 600));
  }

  void settings_dialog::show_tab (const QString& tab)
  {
    if (tab.isEmpty ())
      {
        gui_settings settings;

        tabWidget->setCurrentIndex (settings.value (sd_last_tab).toInt ());
      }
    else
      {
        QHash <QString, QWidget *> tab_hash;
        tab_hash["editor"] = tab_editor;
        tab_hash["editor_styles"] = tab_editor;
        tabWidget->setCurrentIndex (tabWidget->indexOf (tab_hash.value (tab)));
        if (tab == "editor_styles")
          tab_editor_scroll_area->ensureWidgetVisible (group_box_editor_styles);
      }
  }

  void settings_dialog::get_octave_dir (void)
  {
    get_dir (le_octave_dir, tr ("Set Octave Startup Directory"));
  }

  void settings_dialog::get_file_browser_dir (void)
  {
    get_dir (le_file_browser_dir, tr ("Set File Browser Startup Directory"));
  }

  void settings_dialog::get_dir (QLineEdit *line_edit, const QString& title)
  {
    // FIXME: Remove, if for all common KDE versions (bug #54607) is resolved.
    int opts = QFileDialog::ShowDirsOnly | QFileDialog::DontResolveSymlinks;

    gui_settings settings;

    if (! settings.value (global_use_native_dialogs).toBool ())
      opts |= QFileDialog::DontUseNativeDialog;

    QString dir = QFileDialog::getExistingDirectory
      (this, title, line_edit->text (), QFileDialog::Option (opts));

    line_edit->setText (dir);
  }

  void settings_dialog::button_clicked (QAbstractButton *button)
  {
    QDialogButtonBox::ButtonRole button_role = button_box->buttonRole (button);

    if (button_role == QDialogButtonBox::ApplyRole
        || button_role == QDialogButtonBox::AcceptRole)
      {
        write_changed_settings (button_role == QDialogButtonBox::AcceptRole);
        emit apply_new_settings ();
      }

    if (button_role == QDialogButtonBox::RejectRole
        || button_role == QDialogButtonBox::AcceptRole)
      {
        // save last settings dialog's geometry and close

        gui_settings settings;

        settings.setValue (sd_last_tab.key, tabWidget->currentIndex ());
        settings.setValue (sd_geometry.key, saveGeometry ());
        settings.sync ();

        close ();
      }
  }

  void settings_dialog::set_disabled_pref_file_browser_dir (bool disable)
  {
    cb_restore_file_browser_dir->setDisabled (disable);

    if (! disable)
      {
        le_file_browser_dir->setDisabled (cb_restore_file_browser_dir->isChecked ());
        pb_file_browser_dir->setDisabled (cb_restore_file_browser_dir->isChecked ());
      }
    else
      {
        le_file_browser_dir->setDisabled (disable);
        pb_file_browser_dir->setDisabled (disable);
      }
  }

  // slot for updating enabled state of proxy settings
  void settings_dialog::proxy_items_update (void)
  {
    bool use_proxy = use_proxy_server->isChecked ();

    bool manual = false;
    for (int i = 0; i < global_proxy_manual_types.length (); i++)
      {
        if (proxy_type->currentIndex () == global_proxy_manual_types.at (i))
          {
            manual = true;
            break;
          }
      }

    proxy_type->setEnabled (use_proxy);
    proxy_host_name_label->setEnabled (use_proxy && manual);
    proxy_host_name->setEnabled (use_proxy && manual);
    proxy_port_label->setEnabled (use_proxy && manual);
    proxy_port->setEnabled (use_proxy && manual);
    proxy_username_label->setEnabled (use_proxy && manual);
    proxy_username->setEnabled (use_proxy && manual);
    proxy_password_label->setEnabled (use_proxy && manual);
    proxy_password->setEnabled (use_proxy && manual);
  }

  // slots for import/export of shortcut sets

  void settings_dialog::import_shortcut_set (void)
  {
    shortcut_manager& scmgr = m_octave_qobj.get_shortcut_manager ();

    scmgr.import_export (shortcut_manager::OSC_IMPORT);
  }

  void settings_dialog::export_shortcut_set (void)
  {
    shortcut_manager& scmgr = m_octave_qobj.get_shortcut_manager ();

    scmgr.import_export (shortcut_manager::OSC_EXPORT);
  }

  void settings_dialog::default_shortcut_set (void)
  {
    shortcut_manager& scmgr = m_octave_qobj.get_shortcut_manager ();

    scmgr.import_export (shortcut_manager::OSC_DEFAULT);
  }

  void settings_dialog::update_editor_lexers (int def)
  {
#if defined (HAVE_QSCINTILLA)

    gui_settings settings;

    QCheckBox *cb_color_mode
      = group_box_editor_styles->findChild <QCheckBox *> (ed_color_mode.key);

    int m = 0;
    if (cb_color_mode && cb_color_mode->isChecked ())
      m = 1;

    color_picker *c_picker = findChild <color_picker *> (ed_highlight_current_line_color.key);
    if (c_picker)
      {
        if (def != settings_reload_default_colors_flag)
          {
            // Get current value from settings or the default
            c_picker->set_color (settings.color_value (ed_highlight_current_line_color, m));
          }
        else
          {
            // Get the default value
            c_picker->set_color (settings.get_color_value (ed_highlight_current_line_color.def, m));
          }
      }

    // editor styles: create lexer, read settings, and
    // create or update dialog elements
    QsciLexer *lexer;

#  if defined (HAVE_LEXER_OCTAVE)
    lexer = new QsciLexerOctave ();
    update_lexer (lexer, m, def);
    delete lexer;
#  elif defined (HAVE_LEXER_MATLAB)
    lexer = new QsciLexerMatlab ();
    update_lexer (lexer, m, def);
    delete lexer;
#  endif

    lexer = new QsciLexerCPP ();
    update_lexer (lexer, m, def);
    delete lexer;

    lexer = new QsciLexerJava ();
    update_lexer (lexer, m, def);
    delete lexer;

    lexer = new QsciLexerPerl ();
    update_lexer (lexer, m, def);
    delete lexer;

    lexer = new QsciLexerBatch ();
    update_lexer (lexer, m, def);
    delete lexer;

    lexer = new QsciLexerDiff ();
    update_lexer (lexer, m, def);
    delete lexer;

    lexer = new QsciLexerBash ();
    update_lexer (lexer, m, def);
    delete lexer;

    lexer = new octave_txt_lexer ();
    update_lexer (lexer, m, def);
    delete lexer;

#else

    octave_unused_parameter (def);

#endif
  }

#if defined (HAVE_QSCINTILLA)

  void settings_dialog::update_lexer (QsciLexer *lexer, int mode, int def)
  {
    // Get lexer settings and copy from default settings if not yet
    // available in normal settings file
    resource_manager& rmgr = m_octave_qobj.get_resource_manager ();
    rmgr.read_lexer_settings (lexer, mode, def);

    // When reloading default styles, the style tabs do already exists.
    // Otherwise, check if they exist or not.
    QString lexer_name = lexer->language ();

    int index = -1;
    for (int i = 0; i < tabs_editor_lexers->count (); i++)
      {
        if (tabs_editor_lexers->tabText (i) == lexer_name)
          {
            index = i;
            break;
          }
      }

    if (index == -1)
      {
        // This is not an update, call get_lexer_settings for building
        // the settings tab
        get_lexer_settings (lexer);
        return;
      }

    // Update the styles elements in all styles
    int styles[ed_max_lexer_styles];  // array for saving valid styles
    int max_style = rmgr.get_valid_lexer_styles (lexer, styles);
    QWidget *tab = tabs_editor_lexers->widget (index);
    int default_size = 0;
    QString default_family;

    for (int i = 0; i < max_style; i++)  // create dialog elements for all styles
      {
        QString actual_name = lexer->description (styles[i]);
        color_picker *bg_color
          = tab->findChild <color_picker *> (actual_name + "_bg_color");
        if (bg_color)
          {
            // Update
            if (styles[i] == 0)
              bg_color->set_color (lexer->defaultPaper ());
            else
              {
                if (lexer->paper (styles[i]) == lexer->defaultPaper ())
                  bg_color->set_color (settings_color_no_change);
                else
                  bg_color->set_color (lexer->paper (styles[i]));
              }
          }

        color_picker *color = tab->findChild <color_picker *> (actual_name + "_color");
        if (color)
          color->set_color (lexer->color (styles[i]));

        QFont font = lexer->font (styles[i]);

        QCheckBox *cb = tab->findChild <QCheckBox *> (actual_name + "_bold");
        if (cb)
          cb->setChecked (font.bold ());
        cb = tab->findChild <QCheckBox *> (actual_name + "_italic");
        if (cb)
          cb->setChecked (font.italic ());
        cb = tab->findChild <QCheckBox *> (actual_name + "_underline");
        if (cb)
          cb->setChecked (font.underline ());

        QFontComboBox *fcb = tab->findChild <QFontComboBox *> (actual_name + "_font");
        if (fcb)
          {
            if (styles[i] == 0)
              {
                default_family = font.family ();
                fcb->setEditText (default_family);
              }
            else
              {
                if (font.family () == default_family)
                  fcb->setEditText (lexer->description (0));
                else
                  fcb->setEditText (font.family ());
              }
          }
        QSpinBox *fs = tab->findChild <QSpinBox *> (actual_name + "_size");
        if (fs)
          {
            if (styles[i] == 0)
              {
                default_size = font.pointSize ();
                fs->setValue (default_size);
              }
            else
              fs->setValue (font.pointSize () - default_size);
          }
      }

  }

  void settings_dialog::get_lexer_settings (QsciLexer *lexer)
  {
    resource_manager& rmgr = m_octave_qobj.get_resource_manager ();

    int styles[ed_max_lexer_styles];  // array for saving valid styles
    // (enum is not continuous)
    int max_style = rmgr.get_valid_lexer_styles (lexer, styles);
    QGridLayout *style_grid = new QGridLayout ();
    QVector<QLabel *> description (max_style);
    QVector<QFontComboBox *> select_font (max_style);
    QVector<QSpinBox *> font_size (max_style);
    QVector<QCheckBox *> attrib_font (3 * max_style);
    QVector<color_picker *> color (max_style);
    QVector<color_picker *> bg_color (max_style);
    int default_size = 10;
    QFont default_font = QFont ();
    int label_width;
    QColor default_color = QColor ();

    for (int i = 0; i < max_style; i++)  // create dialog elements for all styles
      {
        QString actual_name = lexer->description (styles[i]);
        QFont   actual_font = lexer->font (styles[i]);
        description[i] = new QLabel (actual_name);
        description[i]->setWordWrap (true);
        label_width = 24*description[i]->fontMetrics ().averageCharWidth ();
        description[i]->setMaximumSize (label_width, QWIDGETSIZE_MAX);
        description[i]->setMinimumSize (label_width, 1);
        select_font[i] = new QFontComboBox ();
        select_font[i]->setObjectName (actual_name + "_font");
        select_font[i]->setMaximumSize (label_width, QWIDGETSIZE_MAX);
        select_font[i]->setMinimumSize (label_width, 1);
        font_size[i] = new QSpinBox ();
        font_size[i]->setObjectName (actual_name + "_size");
        if (styles[i] == 0) // the default
          {
            select_font[i]->setCurrentFont (actual_font);
            default_font = actual_font;
            font_size[i]->setRange (6, 24);
            default_size = actual_font.pointSize ();
            font_size[i]->setValue (default_size);
            default_color = lexer->defaultPaper ();
            bg_color[i] = new color_picker (default_color);
          }
        else   // other styles
          {
            select_font[i]->setCurrentFont (actual_font);
            if (actual_font.family () == default_font.family ())
              select_font[i]->setEditText (lexer->description (0));
            font_size[i]->setRange (-4, 4);
            font_size[i]->setValue (actual_font.pointSize ()-default_size);
            font_size[i]->setToolTip (QObject::tr ("Difference to the default size"));
            if (lexer->paper (styles[i]) == default_color)
              bg_color[i] = new color_picker (settings_color_no_change);
            else
              bg_color[i] = new color_picker (lexer->paper (styles[i]));
            bg_color[i]->setToolTip
              (QObject::tr ("Background color, magenta (255, 0, 255) means default"));
          }
        attrib_font[0+3*i] = new QCheckBox (QObject::tr ("b", "short form for bold"));
        attrib_font[1+3*i] = new QCheckBox (QObject::tr ("i", "short form for italic"));
        attrib_font[2+3*i] = new QCheckBox (QObject::tr ("u", "short form for underlined"));
        attrib_font[0+3*i]->setChecked (actual_font.bold ());
        attrib_font[0+3*i]->setObjectName (actual_name + "_bold");
        attrib_font[1+3*i]->setChecked (actual_font.italic ());
        attrib_font[1+3*i]->setObjectName (actual_name + "_italic");
        attrib_font[2+3*i]->setChecked (actual_font.underline ());
        attrib_font[2+3*i]->setObjectName (actual_name + "_underline");
        color[i] = new color_picker (lexer->color (styles[i]));
        color[i]->setObjectName (actual_name + "_color");
        bg_color[i]->setObjectName (actual_name + "_bg_color");
        int column = 1;
        style_grid->addWidget (description[i], i, column++);
        style_grid->addWidget (select_font[i], i, column++);
        style_grid->addWidget (font_size[i], i, column++);
        style_grid->addWidget (attrib_font[0+3*i], i, column++);
        style_grid->addWidget (attrib_font[1+3*i], i, column++);
        style_grid->addWidget (attrib_font[2+3*i], i, column++);
        style_grid->addWidget (color[i], i, column++);
        style_grid->addWidget (bg_color[i], i, column++);
      }

    // place grid with elements into the tab
    QScrollArea *scroll_area = new QScrollArea ();
    QWidget *scroll_area_contents = new QWidget ();
    scroll_area_contents->setObjectName (QString (lexer->language ()) + "_styles");
    scroll_area_contents->setLayout (style_grid);
    scroll_area->setWidget (scroll_area_contents);
    tabs_editor_lexers->addTab (scroll_area, lexer->language ());

    gui_settings settings;

    tabs_editor_lexers->setCurrentIndex (settings.value (sd_last_editor_styles_tab).toInt ());
  }

  void settings_dialog::write_lexer_settings (QsciLexer *lexer)
  {
    gui_settings settings;

    QCheckBox *cb_color_mode
      = group_box_editor_styles->findChild <QCheckBox *> (ed_color_mode.key);
    int mode = 0;
    if (cb_color_mode && cb_color_mode->isChecked ())
      mode = 1;

    settings.setValue (ed_color_mode.key, mode);

    QWidget *tab = tabs_editor_lexers->
      findChild <QWidget *> (QString (lexer->language ()) + "_styles");
    int styles[ed_max_lexer_styles];  // array for saving valid styles
    // (enum is not continuous)

    resource_manager& rmgr = m_octave_qobj.get_resource_manager ();
    int max_style = rmgr.get_valid_lexer_styles (lexer, styles);

    QFontComboBox *select_font;
    QSpinBox *font_size;
    QCheckBox *attrib_font[3];
    color_picker *color;
    color_picker *bg_color;
    int default_size = 10;

    color = findChild <color_picker *> (ed_highlight_current_line_color.key);
    if (color)
      settings.setValue (ed_highlight_current_line_color.key
                          + settings_color_modes_ext[mode], color->color ());

    QString default_font_name
      = settings.value (global_mono_font).toString ();
    QFont default_font = QFont (default_font_name, 10, -1, 0);
    QColor default_color = QColor ();

    for (int i = 0; i < max_style; i++)  // get dialog elements and their contents
      {
        QString actual_name = lexer->description (styles[i]);
        select_font = tab->findChild <QFontComboBox *> (actual_name + "_font");
        font_size = tab->findChild <QSpinBox *> (actual_name + "_size");
        attrib_font[0] = tab->findChild <QCheckBox *> (actual_name + "_bold");
        attrib_font[1] = tab->findChild <QCheckBox *> (actual_name + "_italic");
        attrib_font[2] = tab->findChild <QCheckBox *> (actual_name + "_underline");
        color = tab->findChild <color_picker *> (actual_name + "_color");
        bg_color = tab->findChild <color_picker *> (actual_name + "_bg_color");
        QFont new_font = default_font;
        if (select_font)
          {
            new_font = select_font->currentFont ();
            if (styles[i] == 0)
              default_font = new_font;
            else if (select_font->currentText () == lexer->description (0))
              new_font = default_font;
          }
        if (font_size)
          {
            if (styles[i] == 0)
              {
                default_size = font_size->value ();
                new_font.setPointSize (font_size->value ());
              }
            else
              new_font.setPointSize (font_size->value ()+default_size);
          }
        if (attrib_font[0])
          new_font.setBold (attrib_font[0]->isChecked ());
        if (attrib_font[1])
          new_font.setItalic (attrib_font[1]->isChecked ());
        if (attrib_font[2])
          new_font.setUnderline (attrib_font[2]->isChecked ());
        lexer->setFont (new_font, styles[i]);
        if (styles[i] == 0)
          lexer->setDefaultFont (new_font);
        if (color)
          lexer->setColor (color->color (), styles[i]);
        if (bg_color)
          {
            if (styles[i] == 0)
              {
                default_color = bg_color->color ();
                lexer->setPaper (default_color, styles[i]);
                lexer->setDefaultPaper (default_color);
              }
            else
              {
                if (bg_color->color () == settings_color_no_change)
                  lexer->setPaper (default_color, styles[i]);
                else
                  lexer->setPaper (bg_color->color (), styles[i]);
              }
          }
      }

    const std::string group =
      QString ("Scintilla" + settings_color_modes_ext[mode]).toStdString ();

    lexer->writeSettings (settings, group.c_str ());

    settings.setValue (sd_last_editor_styles_tab.key,
                       tabs_editor_lexers->currentIndex ());
    settings.sync ();
  }

#endif

  void settings_dialog::write_changed_settings (bool closing)
  {
    gui_settings settings;

    // the icon set
    QString widget_icon_set = "NONE";
    if (general_icon_letter->isChecked ())
      widget_icon_set = "LETTER";
    else if (general_icon_graphic->isChecked ())
      widget_icon_set = "GRAPHIC";
    settings.setValue (dw_icon_set.key, widget_icon_set);

    // language
    QString language = comboBox_language->currentText ();
    if (language == tr ("System setting"))
      language = global_language.def.toString ();
    settings.setValue (global_language.key, language);

    // style
    QString selected_style = combo_styles->currentText ();
    if (selected_style == global_style.def.toString ())
      selected_style = global_style.def.toString ();
    settings.setValue (global_style.key, selected_style);

    // dock widget title bar
    settings.setValue (dw_title_custom_style.key, cb_widget_custom_style->isChecked ());
    settings.setValue (dw_title_3d.key, sb_3d_title->value ());
    settings.setValue (dw_title_bg_color.key, m_widget_title_bg_color->color ());
    settings.setValue (dw_title_bg_color_active.key, m_widget_title_bg_color_active->color ());
    settings.setValue (dw_title_fg_color.key, m_widget_title_fg_color->color ());
    settings.setValue (dw_title_fg_color_active.key, m_widget_title_fg_color_active->color ());

    // icon size and theme
    int icon_size = icon_size_large->isChecked () - icon_size_small->isChecked ();
    settings.setValue (global_icon_size.key, icon_size);
    settings.setValue (global_icon_theme_index.key, combo_box_icon_theme->currentIndex ());

    // native file dialogs
    settings.setValue (global_use_native_dialogs.key, cb_use_native_file_dialogs->isChecked ());

    // cursor blinking
    settings.setValue (global_cursor_blinking.key, cb_cursor_blinking->isChecked ());

    // focus follows mouse
    settings.setValue (dw_focus_follows_mouse.key, cb_focus_follows_mouse->isChecked ());

    // promp to exit
    settings.setValue (global_prompt_to_exit.key, cb_prompt_to_exit->isChecked ());

    // status bar
    settings.setValue (global_status_bar.key, cb_status_bar->isChecked ());

    // Octave startup
    settings.setValue (global_restore_ov_dir.key, cb_restore_octave_dir->isChecked ());
    settings.setValue (global_ov_startup_dir.key, le_octave_dir->text ());

    //editor
    settings.setValue (global_use_custom_editor.key, useCustomFileEditor->isChecked ());
    settings.setValue (global_custom_editor.key, customFileEditor->text ());
    settings.setValue (ed_show_line_numbers.key, editor_showLineNumbers->isChecked ());
    settings.setValue (ed_line_numbers_size.key, editor_linenr_size->value ());
    settings.setValue (ed_highlight_current_line.key, editor_highlightCurrentLine->isChecked ());
    settings.setValue (ed_long_line_marker.key, editor_long_line_marker->isChecked ());
    settings.setValue (ed_long_line_marker_line.key, editor_long_line_marker_line->isChecked ());
    settings.setValue (ed_long_line_marker_background.key, editor_long_line_marker_background->isChecked ());
    settings.setValue (ed_long_line_column.key, editor_long_line_column->value ());
    settings.setValue (ed_break_lines.key, editor_break_checkbox->isChecked ());
    settings.setValue (ed_break_lines_comments.key, editor_break_comments_checkbox->isChecked ());
    settings.setValue (ed_wrap_lines.key, editor_wrap_checkbox->isChecked ());
    settings.setValue (ed_code_folding.key, cb_code_folding->isChecked ());
    settings.setValue (ed_show_edit_status_bar.key, cb_edit_status_bar->isChecked ());
    settings.setValue (ed_show_toolbar.key, cb_edit_tool_bar->isChecked ());
    settings.setValue (ed_highlight_all_occurrences.key, editor_highlight_all_occurrences->isChecked ());
    settings.setValue (ed_code_completion.key, editor_codeCompletion->isChecked ());
    settings.setValue (ed_code_completion_threshold.key, editor_spinbox_ac_threshold->value ());
    settings.setValue (ed_code_completion_keywords.key, editor_checkbox_ac_keywords->isChecked ());
    settings.setValue (ed_code_completion_octave_builtins.key, editor_checkbox_ac_builtins->isChecked ());
    settings.setValue (ed_code_completion_octave_functions.key, editor_checkbox_ac_functions->isChecked ());
    settings.setValue (ed_code_completion_document.key, editor_checkbox_ac_document->isChecked ());
    settings.setValue (ed_code_completion_case.key, editor_checkbox_ac_case->isChecked ());
    settings.setValue (ed_code_completion_replace.key, editor_checkbox_ac_replace->isChecked ());
    settings.setValue (ed_auto_endif.key, editor_auto_endif->currentIndex ());
    settings.setValue (ed_show_white_space.key, editor_ws_checkbox->isChecked ());
    settings.setValue (ed_show_white_space_indent.key, editor_ws_indent_checkbox->isChecked ());
    settings.setValue (ed_show_eol_chars.key, cb_show_eol->isChecked ());
    settings.setValue (ed_show_hscroll_bar.key, cb_show_hscrollbar->isChecked ());
    settings.setValue (ed_default_eol_mode.key, combo_eol_mode->currentIndex ());

    settings.setValue (ed_tab_position.key, editor_combox_tab_pos->currentIndex ());
    settings.setValue (ed_tabs_rotated.key, editor_cb_tabs_rotated->isChecked ());
    settings.setValue (ed_tabs_max_width.key, editor_sb_tabs_max_width->value ());

    // Comment strings
    int rb_uncomment = 0;
    for (int i = 0; i < ed_comment_strings_count; i++)
      {
        if (m_rb_comment_strings[i]->isChecked ())
          {
            settings.setValue (ed_comment_str.key, i);
            if (i < 3)
              settings.setValue (ed_comment_str_old.key, i);
            else
              settings.setValue (ed_comment_str_old.key, ed_comment_str.def);
          }
        if (m_rb_uncomment_strings[i]->isChecked ())
          rb_uncomment = rb_uncomment + (1 << i);
      }
    settings.setValue (ed_uncomment_str.key, rb_uncomment);

    settings.setValue (ed_default_enc.key, editor_combo_encoding->currentText ());
    settings.setValue (ed_auto_indent.key, editor_auto_ind_checkbox->isChecked ());
    settings.setValue (ed_tab_indents_line.key, editor_tab_ind_checkbox->isChecked ());
    settings.setValue (ed_backspace_unindents_line.key, editor_bs_unind_checkbox->isChecked ());
    settings.setValue (ed_show_indent_guides.key, editor_ind_guides_checkbox->isChecked ());
    settings.setValue (ed_indent_width.key, editor_ind_width_spinbox->value ());
    settings.setValue (ed_indent_uses_tabs.key, editor_ind_uses_tabs_checkbox->isChecked ());
    settings.setValue (ed_tab_width.key, editor_tab_width_spinbox->value ());
    settings.setValue (ed_restore_session.key, editor_restoreSession->isChecked ());
    settings.setValue (ed_create_new_file.key, editor_create_new_file->isChecked ());
    settings.setValue (ed_hiding_closes_files.key, editor_hiding_closes_files->isChecked ());
    settings.setValue (ed_always_reload_changed_files.key, editor_reload_changed_files->isChecked ());
    settings.setValue (ed_force_newline.key, editor_force_newline->isChecked ());
    settings.setValue (ed_rm_trailing_spaces.key, editor_remove_trailing_spaces->isChecked ());
    settings.setValue (ed_show_dbg_file.key, editor_show_dbg_file->isChecked ());

    // file browser
    settings.setValue (fb_sync_octdir.key, sync_octave_directory->isChecked ());
    settings.setValue (fb_restore_last_dir.key, cb_restore_file_browser_dir->isChecked ());
    settings.setValue (fb_startup_dir.key, le_file_browser_dir->text ());
    settings.setValue (fb_txt_file_ext.key, le_file_browser_extensions->text ());

    // network
    settings.setValue (nr_allow_connection.key, checkbox_allow_web_connect->isChecked ());
    settings.setValue (global_use_proxy.key, use_proxy_server->isChecked ());
    settings.setValue (global_proxy_type.key, proxy_type->currentText ());
    settings.setValue (global_proxy_host.key, proxy_host_name->text ());
    settings.setValue (global_proxy_port.key, proxy_port->text ());
    settings.setValue (global_proxy_user.key, proxy_username->text ());
    settings.setValue (global_proxy_pass.key, proxy_password->text ());

    // command window
    settings.setValue (cs_font_size.key, terminal_fontSize->value ());
    settings.setValue (cs_font.key, terminal_fontName->currentFont ().family ());
    settings.setValue (cs_cursor_use_fgcol.key, terminal_cursorUseForegroundColor->isChecked ());
    settings.setValue (cs_focus_cmd.key, terminal_focus_command->isChecked ());
    settings.setValue (cs_dbg_location.key, terminal_print_dbg_location->isChecked ());
    settings.setValue (cs_hist_buffer.key, terminal_history_buffer->value ());
    write_terminal_colors ();

    // the cursor
    QString cursor_type;
    unsigned int cursor_int = terminal_cursorType->currentIndex ();
    if ((cursor_int > 0) && (cursor_int < cs_cursor_types.size ()))
      cursor_type = QString (cs_cursor_types[cursor_int].data ());
    else
      cursor_type = cs_cursor.def.toString ();

    settings.setValue (cs_cursor.key, cursor_type);

#if defined (HAVE_QSCINTILLA)
    // editor styles: create lexer, get dialog contents, and write settings
    QsciLexer *lexer;

#if defined (HAVE_LEXER_OCTAVE)

    lexer = new QsciLexerOctave ();
    write_lexer_settings (lexer);
    delete lexer;

#elif defined (HAVE_LEXER_MATLAB)

    lexer = new QsciLexerMatlab ();
    write_lexer_settings (lexer);
    delete lexer;

#endif

    lexer = new QsciLexerCPP ();
    write_lexer_settings (lexer);
    delete lexer;

    lexer = new QsciLexerJava ();
    write_lexer_settings (lexer);
    delete lexer;

    lexer = new QsciLexerPerl ();
    write_lexer_settings (lexer);
    delete lexer;

    lexer = new QsciLexerBatch ();
    write_lexer_settings (lexer);
    delete lexer;

    lexer = new QsciLexerDiff ();
    write_lexer_settings (lexer);
    delete lexer;

    lexer = new QsciLexerBash ();
    write_lexer_settings (lexer);
    delete lexer;

    lexer = new octave_txt_lexer ();
    write_lexer_settings (lexer);
    delete lexer;

#endif

    // Workspace
    write_workspace_colors ();

    // Variable editor
    settings.setValue (ve_column_width.key, varedit_columnWidth->value ());
    settings.setValue (ve_row_height.key, varedit_rowHeight->value ());
    settings.setValue (ve_use_terminal_font.key, varedit_useTerminalFont->isChecked ());
    settings.setValue (ve_alternate_rows.key, varedit_alternate->isChecked ());
    settings.setValue (ve_font_name.key, varedit_font->currentFont ().family ());
    settings.setValue (ve_font_size.key, varedit_fontSize->value ());
    write_varedit_colors ();

    // shortcuts

    settings.setValue (sc_prevent_rl_conflicts.key, cb_prevent_readline_conflicts->isChecked ());
    settings.setValue (sc_prevent_rl_conflicts_menu.key, cb_prevent_readline_conflicts_menu->isChecked ());

    shortcut_manager& scmgr = m_octave_qobj.get_shortcut_manager ();
    scmgr.write_shortcuts (settings, closing);

    settings.sync ();
  }

  void settings_dialog::read_workspace_colors (void)
  {
    gui_settings settings;

    // Construct the grid with all color related settings
    QGridLayout *style_grid = new QGridLayout ();
    QVector<QLabel *> description (ws_colors_count);
    QVector<color_picker *> color (ws_colors_count);

    int column = 0;
    const int color_columns = 3;  // place colors in so many columns
    int row = 0;
    int mode = settings.value (ws_color_mode).toInt ();

    m_ws_enable_colors = new QCheckBox (tr ("Enable attribute colors"));
    style_grid->addWidget (m_ws_enable_colors, row++, column, 1, 4);

    m_ws_hide_tool_tips = new QCheckBox (tr ("Hide tools tips"));
    style_grid->addWidget (m_ws_hide_tool_tips, row++, column, 1, 4);
    connect (m_ws_enable_colors, &QCheckBox::toggled,
             m_ws_hide_tool_tips, &QCheckBox::setEnabled);
    m_ws_hide_tool_tips->setChecked
      (settings.value (ws_hide_tool_tips).toBool ());

    QCheckBox *cb_color_mode = new QCheckBox (tr (settings_color_modes.toStdString ().data ()));
    cb_color_mode->setToolTip (tr (settings_color_modes_tooltip.toStdString ().data ()));
    cb_color_mode->setChecked (mode == 1);
    cb_color_mode->setObjectName (ws_color_mode.key);
    connect (m_ws_enable_colors, &QCheckBox::toggled,
             cb_color_mode, &QCheckBox::setEnabled);
    style_grid->addWidget (cb_color_mode, row, column);

    QPushButton *pb_reload_default_colors = new QPushButton (tr (settings_reload_colors.toStdString ().data ()));
    pb_reload_default_colors->setToolTip (tr (settings_reload_colors_tooltip.toStdString ().data ()));
    connect (m_ws_enable_colors, &QCheckBox::toggled,
             pb_reload_default_colors, &QPushButton::setEnabled);
    style_grid->addWidget (pb_reload_default_colors, row+1, column++);

    bool colors_enabled = settings.value (ws_enable_colors).toBool ();

    for (int i = 0; i < ws_colors_count; i++)
      {
        description[i] = new QLabel ("    "
          + tr (ws_color_names.at (i).toStdString ().data ()));
        description[i]->setAlignment (Qt::AlignRight);
        description[i]->setEnabled (colors_enabled);
        connect (m_ws_enable_colors, &QCheckBox::toggled,
                 description[i], &QLabel::setEnabled);

        QColor setting_color = settings.color_value (ws_colors[i], mode);
        color[i] = new color_picker (setting_color);
        color[i]->setObjectName (ws_colors[i].key);
        color[i]->setMinimumSize (30, 10);
        color[i]->setEnabled (colors_enabled);
        connect (m_ws_enable_colors, &QCheckBox::toggled,
                 color[i], &color_picker::setEnabled);

        style_grid->addWidget (description[i], row, 3*column);
        style_grid->addWidget (color[i], row, 3*column+1);
        if (++column > color_columns)
          {
            style_grid->setColumnStretch (4*column, 10);
            row++;
            column = 1;
          }
      }

    // Load enable settings at the end for having signals already connected
    m_ws_enable_colors->setChecked (colors_enabled);
    m_ws_hide_tool_tips->setEnabled (colors_enabled);
    cb_color_mode->setEnabled (colors_enabled);
    pb_reload_default_colors->setEnabled (colors_enabled);

    // place grid with elements into the tab
    workspace_colors_box->setLayout (style_grid);

    // update colors depending on second theme selection or reloading
    // the dfault values
    connect (cb_color_mode, &QCheckBox::stateChanged,
             this, &settings_dialog::update_workspace_colors);
    connect (pb_reload_default_colors, &QPushButton::clicked,
             [=] () { update_workspace_colors (settings_reload_default_colors_flag); });
  }

  void settings_dialog::update_workspace_colors (int def)
  {
    QCheckBox *cb_color_mode
      = workspace_colors_box->findChild <QCheckBox *> (ws_color_mode.key);

    int m = 0;
    if (cb_color_mode && cb_color_mode->isChecked ())
      m = 1;

    gui_settings settings;

    color_picker *c_picker;

    for (unsigned int i = 0; i < ws_colors_count; i++)
      {
        c_picker = workspace_colors_box->findChild <color_picker *> (ws_colors[i].key);
        if (c_picker)
          {
            if (def != settings_reload_default_colors_flag)
              {
                // Get current value from settings or the default
                c_picker->set_color (settings.color_value (ws_colors[i], m));
              }
            else
              {
                // Get the default value
                c_picker->set_color (settings.get_color_value (ws_colors[i].def, m));
              }
          }
      }
  }

  void settings_dialog::write_workspace_colors (void)
  {
    gui_settings settings;

    settings.setValue (ws_enable_colors.key, m_ws_enable_colors->isChecked ());
    settings.setValue (ws_hide_tool_tips.key, m_ws_hide_tool_tips->isChecked ());

    QCheckBox *cb_color_mode
      = workspace_colors_box->findChild <QCheckBox *> (ws_color_mode.key);

    int mode = 0;
    if (cb_color_mode && cb_color_mode->isChecked ())
      mode = 1;

    color_picker *color;

    for (int i = 0; i < ws_colors_count; i++)
      {
        color = workspace_colors_box->findChild <color_picker *> (ws_colors[i].key);
        if (color)
          settings.set_color_value (ws_colors[i], color->color (), mode);
      }

    settings.setValue (ws_color_mode.key, mode);

    settings.sync ();
  }

  void settings_dialog::read_terminal_colors (void)
  {
    gui_settings settings;

    QGridLayout *style_grid = new QGridLayout ();
    QVector<QLabel *> description (cs_colors_count);
    QVector<color_picker *> color (cs_colors_count);

    int mode = settings.value (cs_color_mode).toInt ();

    QCheckBox *cb_color_mode = new QCheckBox (tr (settings_color_modes.toStdString ().data ()));
    cb_color_mode->setToolTip (tr (settings_color_modes_tooltip.toStdString ().data ()));
    cb_color_mode->setChecked (mode == 1);
    cb_color_mode->setObjectName (cs_color_mode.key);
    style_grid->addWidget (cb_color_mode, 0, 0);

    QPushButton *pb_reload_default_colors = new QPushButton (tr (settings_reload_colors.toStdString ().data ()));
    pb_reload_default_colors->setToolTip (tr (settings_reload_colors_tooltip.toStdString ().data ()));
    style_grid->addWidget (pb_reload_default_colors, 1, 0);

    int column = 1;               // column 0 is for the color mode checkbox
    const int color_columns = 2;  // place colors in so many columns
    int row = 0;
    for (unsigned int i = 0; i < cs_colors_count; i++)
      {
        description[i] = new QLabel ("    "
            + tr (cs_color_names.at (i).toStdString ().data ()));
        description[i]->setAlignment (Qt::AlignRight);
        QColor setting_color = settings.color_value (cs_colors[i], mode);
        color[i] = new color_picker (setting_color);
        color[i]->setObjectName (cs_colors[i].key);
        color[i]->setMinimumSize (30, 10);
        style_grid->addWidget (description[i], row, 2*column);
        style_grid->addWidget (color[i], row, 2*column+1);
        if (++column > color_columns)
          {
            style_grid->setColumnStretch (3*column, 10);
            row++;
            column = 1;
          }
      }

    // place grid with elements into the tab
    terminal_colors_box->setLayout (style_grid);

    // update colors depending on second theme selection
    connect (cb_color_mode, &QCheckBox::stateChanged,
             this, &settings_dialog::update_terminal_colors);
    connect (pb_reload_default_colors, &QPushButton::clicked,
             [=] () { update_terminal_colors (settings_reload_default_colors_flag); });
  }

  void settings_dialog::update_terminal_colors (int def)
  {
    QCheckBox *cb_color_mode
      = terminal_colors_box->findChild <QCheckBox *> (cs_color_mode.key);

    int m = 0;
    if (cb_color_mode && cb_color_mode->isChecked ())
      m = 1;

    gui_settings settings;

    color_picker *c_picker;

    for (unsigned int i = 0; i < cs_colors_count; i++)
      {
        c_picker = terminal_colors_box->findChild <color_picker *> (cs_colors[i].key);
        if (c_picker)
          {
            if (def != settings_reload_default_colors_flag)
              {
                // Get current value from settings or the default
                c_picker->set_color (settings.color_value (cs_colors[i], m));
              }
            else
              {
                // Get the default value
                c_picker->set_color (settings.get_color_value (cs_colors[i].def, m));
              }
          }
      }
  }

  void settings_dialog::write_terminal_colors (void)
  {
    QCheckBox *cb_color_mode
      = terminal_colors_box->findChild <QCheckBox *> (cs_color_mode.key);

    int mode = 0;
    if (cb_color_mode && cb_color_mode->isChecked ())
      mode = 1;

    gui_settings settings;

    color_picker *color;

    for (int i = 0; i < cs_color_names.size (); i++)
      {
        color = terminal_colors_box->findChild <color_picker *> (cs_colors[i].key);
        if (color)
          settings.set_color_value (cs_colors[i], color->color (), mode);
      }

    settings.setValue (cs_color_mode.key, mode);

    settings.sync ();
  }

  void settings_dialog::read_varedit_colors (void)
  {
    gui_settings settings;

    QGridLayout *style_grid = new QGridLayout ();
    QVector<QLabel *> description (ve_colors_count);
    QVector<color_picker *> color (ve_colors_count);

    int mode = settings.value (ve_color_mode).toInt ();

    QCheckBox *cb_color_mode = new QCheckBox (tr (settings_color_modes.toStdString ().data ()));
    cb_color_mode->setToolTip (tr (settings_color_modes_tooltip.toStdString ().data ()));
    cb_color_mode->setChecked (mode == 1);
    cb_color_mode->setObjectName (ve_color_mode.key);
    style_grid->addWidget (cb_color_mode, 0, 0);

    QPushButton *pb_reload_default_colors = new QPushButton (tr (settings_reload_colors.toStdString ().data ()));
    pb_reload_default_colors->setToolTip (tr (settings_reload_colors_tooltip.toStdString ().data ()));
    style_grid->addWidget (pb_reload_default_colors, 1, 0);

    int column = 1;
    int color_columns = 2;
    int row = 0;
    for (int i = 0; i < ve_colors_count; i++)
      {
        description[i] = new QLabel ("    "
            + tr (ve_color_names.at (i).toStdString ().data ()));
        description[i]->setAlignment (Qt::AlignRight);

        QColor setting_color = settings.color_value (ve_colors[i], mode);
        color[i] = new color_picker (setting_color);
        color[i]->setObjectName (ve_colors[i].key);
        color[i]->setMinimumSize (30, 10);
        style_grid->addWidget (description[i], row, 2*column);
        style_grid->addWidget (color[i], row, 2*column+1);
        if (++column > color_columns)
          {
            style_grid->setColumnStretch (3*column, 10);
            row++;
            column = 1;
          }
      }

    // place grid with elements into the tab
    varedit_colors_box->setLayout (style_grid);

    // update colors depending on second theme selection
    connect (cb_color_mode, &QCheckBox::stateChanged,
             this, &settings_dialog::update_varedit_colors);
    connect (pb_reload_default_colors, &QPushButton::clicked,
             [=] () { update_varedit_colors (settings_reload_default_colors_flag); });
  }

  void settings_dialog::update_varedit_colors (int def)
  {
    QCheckBox *cb_color_mode
      = varedit_colors_box->findChild <QCheckBox *> (ve_color_mode.key);

    int m = 0;
    if (cb_color_mode && cb_color_mode->isChecked ())
      m = 1;

    gui_settings settings;

    color_picker *c_picker;

    for (unsigned int i = 0; i < ve_colors_count; i++)
      {
        c_picker = varedit_colors_box->findChild <color_picker *> (ve_colors[i].key);
        if (c_picker)
          {
            if (def != settings_reload_default_colors_flag)
              {
                // Get current value from settings or the default
                c_picker->set_color (settings.color_value (ve_colors[i], m));
              }
            else
              {
                // Get the default value
                c_picker->set_color (settings.get_color_value (ve_colors[i].def, m));
              }
          }
      }
  }

  void settings_dialog::write_varedit_colors (void)
  {
    QCheckBox *cb_color_mode
      = varedit_colors_box->findChild <QCheckBox *> (ve_color_mode.key);

    int mode = 0;
    if (cb_color_mode && cb_color_mode->isChecked ())
      mode = 1;

    gui_settings settings;

    color_picker *color;

    for (int i = 0; i < ve_colors_count; i++)
      {
        color = varedit_colors_box->findChild <color_picker *> (ve_colors[i].key);
        if (color)
          settings.set_color_value (ve_colors[i], color->color (), mode);
      }

    settings.setValue (ve_color_mode.key, mode);

    settings.sync ();
  }

OCTAVE_END_NAMESPACE(octave)