/* This file is part of the KDE libraries
   Copyright (C) 2000 Reginald Stadlbauer <reggie@kde.org>

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

   This library 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public License
   along with this library; see the file COPYING.LIB.  If not, write to
   the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
   Boston, MA 02110-1301, USA.
*/

#include "klistwidget.h"

#include <kglobalsettings.h>
#include <kdebug.h>

#include <QtCore/QTimer>
#include <QKeyEvent>
#include <QApplication>

class KListWidget::KListWidgetPrivate
{
public:
    KListWidgetPrivate(KListWidget *q)
        : q(q),
          m_pCurrentItem(nullptr),
          m_eventPos()
    {
    }

    void _k_slotItemEntered(QListWidgetItem *);
    void _k_slotOnViewport();
    void _k_slotSettingsChanged(int);
    void _k_slotAutoSelect();
    void _k_slotEmitExecute(QListWidgetItem *item);

    KListWidget *q;
    bool m_bUseSingle : 1;
    bool m_bChangeCursorOverItem : 1;

    QListWidgetItem *m_pCurrentItem;
    QTimer *m_pAutoSelect;
    int m_autoSelectDelay;
    QPoint m_eventPos;
};

KListWidget::KListWidget(QWidget *parent)
    : QListWidget(parent), d(new KListWidgetPrivate(this))
{
    connect(this, SIGNAL(viewportEntered()),
            this, SLOT(_k_slotOnViewport()));
    connect(this, SIGNAL(itemEntered(QListWidgetItem*)),
            this, SLOT(_k_slotItemEntered(QListWidgetItem*)));
    d->_k_slotSettingsChanged(KGlobalSettings::SETTINGS_MOUSE);
    connect(KGlobalSettings::self(), SIGNAL(settingsChanged(int)), SLOT(_k_slotSettingsChanged(int)));

    d->m_pAutoSelect = new QTimer(this);
    connect(d->m_pAutoSelect, SIGNAL(timeout()),
            this, SLOT(_k_slotAutoSelect()));
}

KListWidget::~KListWidget()
{
    delete d;
}

void KListWidget::KListWidgetPrivate::_k_slotItemEntered(QListWidgetItem *item)
{
    if (item && m_bChangeCursorOverItem && m_bUseSingle) {
        q->viewport()->setCursor(QCursor(Qt::OpenHandCursor));
    }

    if (item && (m_autoSelectDelay > -1) && m_bUseSingle) {
        m_pAutoSelect->setSingleShot(true);
        m_pAutoSelect->start(m_autoSelectDelay);
        m_pCurrentItem = item;
    }
}

void KListWidget::KListWidgetPrivate::_k_slotOnViewport()
{
    if (m_bChangeCursorOverItem) {
        q->viewport()->unsetCursor();
    }

    m_pAutoSelect->stop();
    m_pCurrentItem = nullptr;
}

void KListWidget::KListWidgetPrivate::_k_slotSettingsChanged(int category)
{
    if (category != KGlobalSettings::SETTINGS_MOUSE) {
        return;
    }
    m_bUseSingle = q->style()->styleHint(QStyle::SH_ItemView_ActivateItemOnSingleClick);

    q->disconnect(q, SIGNAL(itemClicked(QListWidgetItem*)));
    q->disconnect(q, SIGNAL(itemDoubleClicked(QListWidgetItem*)));

    if (m_bUseSingle) {
        q->connect(q, SIGNAL(itemClicked(QListWidgetItem*)),
                   SLOT(_k_slotEmitExecute(QListWidgetItem*)));
    } else {
        q->connect(q, SIGNAL(itemDoubleClicked(QListWidgetItem*)),
                   SLOT(_k_slotEmitExecute(QListWidgetItem*)));
    }

    m_bChangeCursorOverItem = KGlobalSettings::changeCursorOverIcon();
    m_autoSelectDelay = KGlobalSettings::autoSelectDelay();

    if (!m_bUseSingle || !m_bChangeCursorOverItem) {
        q->viewport()->unsetCursor();
    }
}

void KListWidget::KListWidgetPrivate::_k_slotAutoSelect()
{
    // check that the item still exists
    if (q->row(m_pCurrentItem) == -1) {
        return;
    }

    //Give this widget the keyboard focus.
    if (!q->hasFocus()) {
        q->setFocus();
    }

    Qt::KeyboardModifiers keybstate = QApplication::keyboardModifiers();

    QListWidgetItem *previousItem = q->currentItem();
    q->setCurrentItem(m_pCurrentItem);

    if (m_pCurrentItem) {
        //Shift pressed?
        if ((keybstate & Qt::ShiftModifier)) {
            bool block = q->signalsBlocked();
            q->blockSignals(true);

            //No Ctrl? Then clear before!
            if (!(keybstate & Qt::ControlModifier)) {
                q->clearSelection();
            }

            bool select = !m_pCurrentItem->isSelected();
            bool update = q->viewport()->updatesEnabled();
            q->viewport()->setUpdatesEnabled(false);

            bool down = q->row(previousItem) < q->row(m_pCurrentItem);
            QListWidgetItem *it = down ? previousItem : m_pCurrentItem;

            for (int i = q->row(it); i < q->count(); i++) {
                if (down && q->item(i) == m_pCurrentItem) {
                    m_pCurrentItem->setSelected(select);
                    break;
                }

                if (!down && q->item(i) == previousItem) {
                    previousItem->setSelected(select);
                    break;
                }
                it->setSelected(select);
            }

            q->blockSignals(block);
            q->viewport()->setUpdatesEnabled(update);

            emit q->itemSelectionChanged();

            if (q->selectionMode() == QAbstractItemView::SingleSelection) {
                q->emit itemSelectionChanged();
            }
        } else if ((keybstate & Qt::ControlModifier)) {
            m_pCurrentItem->setSelected(!m_pCurrentItem->isSelected());
        } else {
            bool block = q->signalsBlocked();
            q->blockSignals(true);

            if (!m_pCurrentItem->isSelected()) {
                q->clearSelection();
            }

            q->blockSignals(block);

            m_pCurrentItem->setSelected(true);
        }
    } else {
        kDebug() << "That's not supposed to happen!!!!";
    }
}

void KListWidget::KListWidgetPrivate::_k_slotEmitExecute(QListWidgetItem *item)
{
    Qt::KeyboardModifiers keybstate = QApplication::keyboardModifiers();

    m_pAutoSelect->stop();

    //Don't emit executed if in SC mode and Shift or Ctrl are pressed
    if (!(m_bUseSingle && ((keybstate & Qt::ShiftModifier) || (keybstate & Qt::ControlModifier)))) {
        emit q->executed(item);
        if (!m_eventPos.isNull()) {
            emit q->executed(item, m_eventPos);
        }
    }
}

//
// 2000-16-01 Espen Sand
// This widget is used in dialogs. It should ignore
// F1 (and combinations) and Escape since these are used
// to start help or close the dialog. This functionality
// should be done in QListView but it is not (at least now)
//
void KListWidget::keyPressEvent(QKeyEvent *e)
{
    if (e->key() == Qt::Key_Escape) {
        e->ignore();
    } else if (e->key() == Qt::Key_F1) {
        e->ignore();
    } else {
        QListWidget::keyPressEvent(e);
    }
}

void KListWidget::focusOutEvent(QFocusEvent *fe)
{
    d->m_pAutoSelect->stop();

    QListWidget::focusOutEvent(fe);
}

void KListWidget::leaveEvent(QEvent *e)
{
    d->m_pAutoSelect->stop();

    QListWidget::leaveEvent(e);
}

void KListWidget::mousePressEvent(QMouseEvent *e)
{
    if ((selectionMode() == QAbstractItemView::ExtendedSelection) && (e->modifiers() & Qt::ShiftModifier) && !(e->modifiers() & Qt::ControlModifier)) {
        bool block = signalsBlocked();
        blockSignals(true);

        clearSelection();

        blockSignals(block);
    }

    QListWidget::mousePressEvent(e);
}

void KListWidget::mouseDoubleClickEvent(QMouseEvent *e)
{
    QPoint oldPos = d->m_eventPos;
    d->m_eventPos = e->globalPos();
    QListWidget::mouseDoubleClickEvent(e);
    d->m_eventPos = oldPos;
}

void KListWidget::mouseReleaseEvent(QMouseEvent *e)
{
    QPoint oldPos = d->m_eventPos;
    d->m_eventPos = e->globalPos();
    QListWidget::mouseReleaseEvent(e);
    d->m_eventPos = oldPos;
}

#include "moc_klistwidget.cpp"
