/* This file is part of the KDE project
   Copyright (C) 2004  Esben Mose Hansen <kde@mosehansen.dk>
   Copyright (C) by Andrew Stanley-Jones <asj@cban.com>
   Copyright (C) 2000 by Carsten Pfeiffer <pfeiffer@kde.org>

   This program 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 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 "klipperpopup.h"

#include <QApplication>
#include "klipper_debug.h"
#include <QDesktopWidget>
#include <QKeyEvent>
#include <QWidgetAction>

#include <KHelpMenu>
#include <KLineEdit>
#include <KLocalizedString>
#include <KWindowInfo>

#include "history.h"
#include "klipper.h"
#include "popupproxy.h"

namespace {
    static const int TOP_HISTORY_ITEM_INDEX = 2;
}

// #define DEBUG_EVENTS__

#ifdef DEBUG_EVENTS__
kdbgstream& operator<<( kdbgstream& stream, const QKeyEvent& e ) {
    stream << "(QKeyEvent(text=" << e.text() << ",key=" << e.key() << ( e.isAccepted()?",accepted":",ignored)" ) << ",count=" << e.count();
    if ( e.modifiers() & Qt::AltModifier ) {
        stream << ",ALT";
    }
    if ( e.modifiers() & Qt::ControlModifier ) {
        stream << ",CTRL";
    }
    if ( e.modifiers() & Qt::MetaModifier ) {
        stream << ",META";
    }
    if ( e.modifiers() & Qt::ShiftModifier ) {
        stream << ",SHIFT";
    }
    if ( e.isAutoRepeat() ) {
        stream << ",AUTOREPEAT";
    }
    stream << ")";

    return stream;
}
#endif

KlipperPopup::KlipperPopup( History* history )
    : m_dirty( true ),
      m_textForEmptyHistory( i18n( "<empty clipboard>" ) ),
      m_textForNoMatch( i18n( "<no matches>" ) ),
      m_history( history ),
      m_helpMenu( nullptr ),
      m_popupProxy( nullptr ),
      m_filterWidget( nullptr ),
      m_filterWidgetAction( nullptr ),
      m_nHistoryItems( 0 ),
      m_showHelp(true),
      m_lastEvent(nullptr)
{
    ensurePolished();
    KWindowInfo windowInfo( winId(), NET::WMGeometry );
    QRect geometry = windowInfo.geometry();
    QRect screen = qApp->desktop()->screenGeometry(geometry.center());
    int menuHeight = ( screen.height() ) * 3/4;
    int menuWidth = ( screen.width() )  * 1/3;

    m_popupProxy = new PopupProxy( this, menuHeight, menuWidth );

    connect(this, &KlipperPopup::aboutToShow, this, &KlipperPopup::slotAboutToShow);
}

KlipperPopup::~KlipperPopup() {

}

void KlipperPopup::slotAboutToShow() {
    if ( m_filterWidget ) {
        if ( !m_filterWidget->text().isEmpty() ) {
            m_dirty = true;
            m_filterWidget->clear();
        }
    }
    ensureClean();

}

void KlipperPopup::ensureClean() {
    // If the history is unchanged since last menu build, the is no reason
    // to rebuild it,
    if ( m_dirty ) {
        rebuild();
    }

}

void KlipperPopup::buildFromScratch() {
    addSection(QIcon::fromTheme(QStringLiteral("klipper")), i18n("Klipper - Clipboard Tool"));

    m_filterWidget = new KLineEdit(this);
    m_filterWidget->setFocusPolicy( Qt::NoFocus );
    m_filterWidget->setPlaceholderText(i18n("Search..."));
    m_filterWidgetAction = new QWidgetAction(this);
    m_filterWidgetAction->setDefaultWidget(m_filterWidget);
    addAction(m_filterWidgetAction);

    addSeparator();
    for (int i = 0; i < m_actions.count(); i++) {

        if (i + 1 == m_actions.count() && m_showHelp) {
            if (!m_helpMenu) {
                m_helpMenu = new KHelpMenu( this, i18n("KDE cut & paste history utility"), false );
            }
            addMenu(m_helpMenu->menu())->setIcon(QIcon::fromTheme(QStringLiteral("help-contents")));
            addSeparator();
        }

        addAction(m_actions.at(i));
    }
}

void KlipperPopup::rebuild( const QString& filter ) {
    if (actions().isEmpty()) {
        buildFromScratch();
    } else {
        for ( int i=0; i<m_nHistoryItems; i++ ) {
            Q_ASSERT(TOP_HISTORY_ITEM_INDEX < actions().count());
            removeAction(actions().at(TOP_HISTORY_ITEM_INDEX));
        }
    }

    // We search case insensitive until one uppercased character appears in the search term
    QRegularExpression filterexp( filter, filter.toLower() == filter ?
                                          QRegularExpression::CaseInsensitiveOption
                                          : QRegularExpression::NoPatternOption );

    QPalette palette = m_filterWidget->palette();
    if ( filterexp.isValid() ) {
        palette.setColor( m_filterWidget->foregroundRole(), palette.color(foregroundRole()) );
    } else {
        palette.setColor( m_filterWidget->foregroundRole(), Qt::red );
    }
    m_nHistoryItems = m_popupProxy->buildParent( TOP_HISTORY_ITEM_INDEX, filterexp );
    if ( m_nHistoryItems == 0 ) {
        if ( m_history->empty() ) {
            insertAction(actions().at(TOP_HISTORY_ITEM_INDEX), new QAction(m_textForEmptyHistory, this));
        } else {
            palette.setColor( m_filterWidget->foregroundRole(), Qt::red );
            insertAction(actions().at(TOP_HISTORY_ITEM_INDEX), new QAction(m_textForNoMatch, this));
        }
        m_nHistoryItems++;
    } else {
        if ( history()->topIsUserSelected() ) {
            actions().at(TOP_HISTORY_ITEM_INDEX)->setCheckable(true);
            actions().at(TOP_HISTORY_ITEM_INDEX)->setChecked(true);
        }
    }
    m_filterWidget->setPalette( palette );
    m_dirty = false;
}

void KlipperPopup::slotTopIsUserSelectedSet() {
    if ( !m_dirty && m_nHistoryItems > 0 && history()->topIsUserSelected() ) {
        actions().at(TOP_HISTORY_ITEM_INDEX)->setCheckable(true);
        actions().at(TOP_HISTORY_ITEM_INDEX)->setChecked(true);
    }
}

void KlipperPopup::plugAction( QAction* action ) {
    m_actions.append(action);
}


/* virtual */
void KlipperPopup::keyPressEvent( QKeyEvent* e ) {
    // Most events are send down directly to the m_filterWidget. 
    // If the m_filterWidget does not handle the event, it will 
    // come back to this method. Remembering the last event stops
    // the infinite event loop
    if (m_lastEvent == e) {
        m_lastEvent= nullptr;
        return;
    }
    m_lastEvent= e;
    // If alt-something is pressed, select a shortcut
    // from the menu. Do this by sending a keyPress
    // without the alt-modifier to the superobject.
    if ( e->modifiers() & Qt::AltModifier ) {
        QKeyEvent ke( QEvent::KeyPress,
                      e->key(),
                      e->modifiers() ^ Qt::AltModifier,
                      e->text(),
                      e->isAutoRepeat(),
                      e->count() );
        QMenu::keyPressEvent( &ke );
#ifdef DEBUG_EVENTS__
        qCDebug(KLIPPER_LOG) << "Passing this event to ancestor (KMenu): " << e << "->" << ke;
#endif
        if (ke.isAccepted()) {
            e->accept();
            return;
        } else {
            e->ignore();
        }
    }

    // Otherwise, send most events to the search
    // widget, except a few used for navigation:
    // These go to the superobject.
    switch( e->key() ) {
    case Qt::Key_Up:
    case Qt::Key_Down:
    case Qt::Key_Right:
    case Qt::Key_Left:
    case Qt::Key_Tab:
    case Qt::Key_Backtab:
    case Qt::Key_Escape:
    {
#ifdef DEBUG_EVENTS__
        qCDebug(KLIPPER_LOG) << "Passing this event to ancestor (KMenu): " << e;
#endif
        QMenu::keyPressEvent(e);

        break;
    }
    case Qt::Key_Return:
    case Qt::Key_Enter:
    {
        QMenu::keyPressEvent(e);
        this->hide();

        if (activeAction() ==  m_filterWidgetAction)
            setActiveAction(actions().at(TOP_HISTORY_ITEM_INDEX));

        break;
    }
    default:
    {
#ifdef DEBUG_EVENTS__
        qCDebug(KLIPPER_LOG) << "Passing this event down to child (KLineEdit): " << e;
#endif
        setActiveAction(actions().at(actions().indexOf(m_filterWidgetAction)));
        QString lastString = m_filterWidget->text();

        QApplication::sendEvent(m_filterWidget, e);
        if (m_filterWidget->text() != lastString) {
            m_dirty = true;
            rebuild(m_filterWidget->text());
        }

        break;
    } //default:
    } //case
    m_lastEvent= nullptr;
}


void KlipperPopup::slotSetTopActive()
{
  if (actions().size() > TOP_HISTORY_ITEM_INDEX) {
    setActiveAction(actions().at(TOP_HISTORY_ITEM_INDEX));
  }
}