/*
    This file is part of the KDE libraries
    SPDX-FileCopyrightText: 1997 Martin Jones <mjones@kde.org>

    SPDX-License-Identifier: LGPL-2.0-or-later
*/
//-----------------------------------------------------------------------------
// Selector widgets for KDE Color Selector, but probably useful for other
// stuff also.

#ifndef KSELECTOR_H
#define KSELECTOR_H

#include <kwidgetsaddons_export.h>

#include <QAbstractSlider>
#include <QGradient>
#include <QWidget>
#include <memory>

/**
 * @class KSelector kselector.h KSelector
 *
 * KSelector is the base class for other widgets which
 * provides the ability to choose from a one-dimensional
 * range of values. An example is the KGradientSelector
 * which allows to choose from a range of colors.
 *
 * A custom drawing routine for the widget surface has
 * to be provided by the subclass.
 */
class KWIDGETSADDONS_EXPORT KSelector : public QAbstractSlider
{
    Q_OBJECT
    Q_PROPERTY(int value READ value WRITE setValue)
    Q_PROPERTY(int minValue READ minimum WRITE setMinimum)
    Q_PROPERTY(int maxValue READ maximum WRITE setMaximum)
    Q_PROPERTY(bool indent READ indent WRITE setIndent)
    Q_PROPERTY(Qt::ArrowType arrowDirection READ arrowDirection WRITE setArrowDirection)
public:
    /**
     * Constructs a horizontal one-dimensional selection widget.
     */
    explicit KSelector(QWidget *parent = nullptr);
    /**
     * Constructs a one-dimensional selection widget with
     * a given orientation.
     */
    explicit KSelector(Qt::Orientation o, QWidget *parent = nullptr);
    /*
     * Destructs the widget.
     */
    ~KSelector() override;

    /**
     * @return the rectangle on which subclasses should draw.
     */
    QRect contentsRect() const;

    /**
     * Sets the indent option of the widget to i.
     * This determines whether a shaded frame is drawn.
     */
    void setIndent(bool i);

    /**
     * @return whether the indent option is set.
     */
    bool indent() const;

    /**
     * Sets the arrow direction.
     */
    void setArrowDirection(Qt::ArrowType direction);

    /**
     * @return the current arrow direction
     */
    Qt::ArrowType arrowDirection() const;

protected:
    /**
     * Override this function to draw the contents of the control.
     * The default implementation does nothing.
     *
     * Draw only within contentsRect().
     */
    virtual void drawContents(QPainter *);
    /**
     * Override this function to draw the cursor which
     * indicates the current value.
     */
    virtual void drawArrow(QPainter *painter, const QPoint &pos);

    void paintEvent(QPaintEvent *) override;
    void mousePressEvent(QMouseEvent *e) override;
    void mouseMoveEvent(QMouseEvent *e) override;
    void mouseReleaseEvent(QMouseEvent *e) override;
    void wheelEvent(QWheelEvent *) override;

private:
    KWIDGETSADDONS_NO_EXPORT QPoint calcArrowPos(int val);
    KWIDGETSADDONS_NO_EXPORT void moveArrow(const QPoint &pos);

private:
    friend class KSelectorPrivate;
    std::unique_ptr<class KSelectorPrivate> const d;

    Q_DISABLE_COPY(KSelector)
};

/**
 * @class KGradientSelector kselector.h KGradientSelector
 *
 * The KGradientSelector widget allows the user to choose
 * from a one-dimensional range of colors which is given as a
 * gradient between two colors provided by the programmer.
 *
 * \image html kgradientselector.png "KGradientSelector Widget"
 */
class KWIDGETSADDONS_EXPORT KGradientSelector : public KSelector
{
    Q_OBJECT

    Q_PROPERTY(QColor firstColor READ firstColor WRITE setFirstColor)
    Q_PROPERTY(QColor secondColor READ secondColor WRITE setSecondColor)
    Q_PROPERTY(QString firstText READ firstText WRITE setFirstText)
    Q_PROPERTY(QString secondText READ secondText WRITE setSecondText)

public:
    /**
     * Constructs a horizontal color selector which
     * contains a gradient between white and black.
     */
    explicit KGradientSelector(QWidget *parent = nullptr);
    /**
     * Constructs a colors selector with orientation o which
     * contains a gradient between white and black.
     */
    explicit KGradientSelector(Qt::Orientation o, QWidget *parent = nullptr);
    /**
     * Destructs the widget.
     */
    ~KGradientSelector() override;

    /**
     * Sets the colors that make up the gradient. Any previously set colors
     * are removed.
     * @since 4.5
     */
    void setStops(const QGradientStops &stops);

    /**
     * Get the colors that make up the gradient.
     * @since 4.5
     */
    QGradientStops stops() const;

    /**
     * Sets the two colors which span the gradient.
     */
    void setColors(const QColor &col1, const QColor &col2);
    void setText(const QString &t1, const QString &t2);

    /**
     * Set each color on its own.
     */
    void setFirstColor(const QColor &col);
    void setSecondColor(const QColor &col);

    /**
     * Set each description on its own
     */
    void setFirstText(const QString &t);
    void setSecondText(const QString &t);

    QColor firstColor() const;
    QColor secondColor() const;

    QString firstText() const;
    QString secondText() const;

protected:
    void drawContents(QPainter *) override;
    virtual QSize minimumSize() const;

private:
    friend class KGradientSelectorPrivate;
    std::unique_ptr<class KGradientSelectorPrivate> const d;

    Q_DISABLE_COPY(KGradientSelector)
};

#endif // KSELECTOR_H