/*
    nanogui/imagepanel.h -- Image panel widget which shows a number of
    square-shaped icons

    NanoGUI was developed by Wenzel Jakob <wenzel.jakob@epfl.ch>.
    The widget drawing code is based on the NanoVG demo application
    by Mikko Mononen.

    All rights reserved. Use of this source code is governed by a
    BSD-style license that can be found in the LICENSE.txt file.
*/
/** \file */

#pragma once

#include <nanogui/widget.h>

NAMESPACE_BEGIN(nanogui)

/**
 * \class ImagePanel imagepanel.h nanogui/imagepanel.h
 *
 * \brief Image panel widget which shows a number of square-shaped icons.
 */
class NANOGUI_EXPORT ImagePanel : public Widget {
public:
    typedef std::vector<std::pair<int, std::string>> Images;
public:
    ImagePanel(Widget *parent);

    void set_images(const Images &data) { m_images = data; }
    const Images& images() const { return m_images; }

    const std::function<void(int)> &callback() const { return m_callback; }
    void set_callback(const std::function<void(int)> &callback) { m_callback = callback; }

    virtual bool mouse_motion_event(const Vector2i &p, const Vector2i &rel, int button,
                                    int modifiers) override;
    virtual bool mouse_button_event(const Vector2i &p, int button, bool down,
                                    int modifiers) override;
    virtual Vector2i preferred_size(NVGcontext *ctx) const override;
    virtual void draw(NVGcontext *ctx) override;

protected:
    Vector2i grid_size() const;
    int index_for_position(const Vector2i &p) const;
protected:
    Images m_images;
    std::function<void(int)> m_callback;
    int m_thumb_size;
    int m_spacing;
    int m_margin;
    int m_mouse_index;
};

NAMESPACE_END(nanogui)
