// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only

#ifndef QABSTRACTITEMDELEGATE_H
#define QABSTRACTITEMDELEGATE_H

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

QT_REQUIRE_CONFIG(itemviews);

QT_BEGIN_NAMESPACE

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 = 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);
    // for widget editors
    bool handleEditorEvent(QObject *object, QEvent *event);

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

    virtual QList<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 = nullptr);

private:
    Q_DECLARE_PRIVATE(QAbstractItemDelegate)
    Q_DISABLE_COPY(QAbstractItemDelegate)
    Q_PRIVATE_SLOT(d_func(), void _q_commitDataAndCloseEditor(QWidget*))
};

QT_END_NAMESPACE

#endif // QABSTRACTITEMDELEGATE_H
