/*  -*- C++ -*-
    This file is part of the KDE libraries
    Copyright (C) 1997 Tim D. Gilman (tdgilman@best.org)
              (C) 1998-2001 Mirko Boehm (mirko@kde.org)
              (C) 2007 John Layt <john@layt.net>
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    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.
*/

#ifndef KDATEPICKER_H
#define KDATEPICKER_H

#include <kwidgetsaddons_export.h>

#include <QtCore/QDateTime>
#include <QFrame>

class QLineEdit;
class KDateTable;

/**
 * @class KDatePicker kdatepicker.h KDatePicker
 *
 * @short A date selection widget.
 *
 * Provides a widget for calendar date input.
 *
 *     Different from the
 *     previous versions, it now emits two types of signals, either
 * dateSelected() or dateEntered() (see documentation for both
 *     signals).
 *
 *     A line edit has been added in the newer versions to allow the user
 *     to select a date directly by entering numbers like 19990101
 *     or 990101.
 *
 * \image html kdatepicker.png "KDatePicker Widget"
 *
 *     @author Tim Gilman, Mirko Boehm
 *
 **/
class KWIDGETSADDONS_EXPORT KDatePicker: public QFrame
{
    Q_OBJECT
    Q_PROPERTY(QDate date READ date WRITE setDate NOTIFY dateChanged USER true)
    Q_PROPERTY(bool closeButton READ hasCloseButton WRITE setCloseButton)
    Q_PROPERTY(int fontSize READ fontSize WRITE setFontSize)

public:
    /**
     * The constructor. The current date will be displayed initially.
     **/
    explicit KDatePicker(QWidget *parent = nullptr);

    /**
     * The constructor. The given date will be displayed initially.
     **/
    explicit KDatePicker(const QDate &dt, QWidget *parent = nullptr);

    /**
     * The destructor.
     **/
    virtual ~KDatePicker();

    /** The size hint for date pickers. The size hint recommends the
     *   minimum size of the widget so that all elements may be placed
     *  without clipping. This sometimes looks ugly, so when using the
     *  size hint, try adding 28 to each of the reported numbers of
     *  pixels.
     **/
    QSize sizeHint() const Q_DECL_OVERRIDE;

    /**
     * Sets the date.
     *
     *  @returns @p false and does not change anything if the date given is invalid.
     **/
    bool setDate(const QDate &date);

    /**
     * @returns the selected date.
     */
    const QDate &date() const;

    /**
     * @returns the KDateTable widget child of this KDatePicker
     * widget.
     */

    /**
     * Sets the font size of the widgets elements.
     **/
    void setFontSize(int);

    /**
     * Returns the font size of the widget elements.
     */
    int fontSize() const;

    /**
     * By calling this method with @p enable = true, KDatePicker will show
     * a little close-button in the upper button-row. Clicking the
     * close-button will cause the KDatePicker's topLevelWidget()'s close()
     * method being called. This is mostly useful for toplevel datepickers
     * without a window manager decoration.
     * @see hasCloseButton
     */
    void setCloseButton(bool enable);

    /**
     * @returns true if a KDatePicker shows a close-button.
     * @see setCloseButton
     */
    bool hasCloseButton() const;

protected:
    /// to catch move keyEvents when QLineEdit has keyFocus
    bool eventFilter(QObject *o, QEvent *e) Q_DECL_OVERRIDE;
    /// the resize event
    void resizeEvent(QResizeEvent *) Q_DECL_OVERRIDE;
    void changeEvent(QEvent *event) Q_DECL_OVERRIDE;

protected Q_SLOTS:
    void dateChangedSlot(const QDate &date);
    void tableClickedSlot();
    void monthForwardClicked();
    void monthBackwardClicked();
    void yearForwardClicked();
    void yearBackwardClicked();
    void selectMonthClicked();
    void selectYearClicked();
    void uncheckYearSelector();
    void lineEnterPressed();
    void todayButtonClicked();
    void weekSelected(int);

Q_SIGNALS:
    /** This signal is emitted each time the selected date is changed.
     *  Usually, this does not mean that the date has been entered,
     *  since the date also changes, for example, when another month is
     *  selected.
     *  @see dateSelected
     */
    void dateChanged(const QDate &date);

    /** This signal is emitted each time a day has been selected by
     *  clicking on the table (hitting a day in the current month). It
     *  has the same meaning as dateSelected() in older versions of
     *  KDatePicker.
     */
    void dateSelected(const QDate &date);

    /** This signal is emitted when enter is pressed and a VALID date
     *  has been entered before into the line edit. Connect to both
     *  dateEntered() and dateSelected() to receive all events where the
     *  user really enters a date.
     */
    void dateEntered(const QDate &date);

    /** This signal is emitted when the day has been selected by
     *  clicking on it in the table.
     */
    void tableClicked();

private:
    KDateTable *dateTable() const;
    void initWidget(const QDate &date);
    class KDatePickerPrivate;
    friend class KDatePickerPrivate;
    KDatePickerPrivate *const d;
};

#endif //  KDATEPICKER_H
