/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtWidgets module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
** https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/

#ifndef QABSTRACTITEMDELEGATE_H
#define QABSTRACTITEMDELEGATE_H

#include <QtWidgets/qtwidgetsglobal.h>
#include <QtCore/qobject.h>
#include <QtWidgets/qstyleoption.h>

QT_BEGIN_NAMESPACE


#ifndef QT_NO_ITEMVIEWS

class QPainter;
class QModelIndex;
class QAbstractItemModel;
class QAbstractItemView;
class QHelpEvent;
class QAbstractItemDelegatePrivate;

class Q_WIDGETS_EXPORT QAbstractItemDelegate : public QObject
{
    Q_OBJECT

public:

    enum EndEditHint {
        NoHint,
        EditNextItem,
        EditPreviousItem,
        SubmitModelCache,
        RevertModelCache
    };

    explicit QAbstractItemDelegate(QObject *parent = Q_NULLPTR);
    virtual ~QAbstractItemDelegate();

    // painting
    virtual void paint(QPainter *painter,
                       const QStyleOptionViewItem &option,
                       const QModelIndex &index) const = 0;

    virtual QSize sizeHint(const QStyleOptionViewItem &option,
                           const QModelIndex &index) const = 0;

    // editing
    virtual QWidget *createEditor(QWidget *parent,
                                  const QStyleOptionViewItem &option,
                                  const QModelIndex &index) const;

    virtual void destroyEditor(QWidget *editor, const QModelIndex &index) const;

    virtual void setEditorData(QWidget *editor, const QModelIndex &index) const;

    virtual void setModelData(QWidget *editor,
                              QAbstractItemModel *model,
                              const QModelIndex &index) const;

    virtual void updateEditorGeometry(QWidget *editor,
                                      const QStyleOptionViewItem &option,
                                      const QModelIndex &index) const;

    // for non-widget editors
    virtual bool editorEvent(QEvent *event,
                             QAbstractItemModel *model,
                             const QStyleOptionViewItem &option,
                             const QModelIndex &index);

    static QString elidedText(const QFontMetrics &fontMetrics, int width,
                              Qt::TextElideMode mode, const QString &text);

    virtual bool helpEvent(QHelpEvent *event,
                           QAbstractItemView *view,
                           const QStyleOptionViewItem &option,
                           const QModelIndex &index);

    virtual QVector<int> paintingRoles() const;

Q_SIGNALS:
    void commitData(QWidget *editor);
    void closeEditor(QWidget *editor, QAbstractItemDelegate::EndEditHint hint = NoHint);
    void sizeHintChanged(const QModelIndex &);

protected:
    QAbstractItemDelegate(QObjectPrivate &, QObject *parent = Q_NULLPTR);
private:
    Q_DECLARE_PRIVATE(QAbstractItemDelegate)
    Q_DISABLE_COPY(QAbstractItemDelegate)
    Q_PRIVATE_SLOT(d_func(), void _q_commitDataAndCloseEditor(QWidget*))
};

#endif // QT_NO_ITEMVIEWS

QT_END_NAMESPACE

#endif // QABSTRACTITEMDELEGATE_H