// SPDX-FileCopyrightText: 2025 Filip Leonarski, Paul Scherrer Institute <filip.leonarski@psi.ch>
// SPDX-License-Identifier: GPL-3.0-only

#pragma once

#include <QToolBar>
#include <QElapsedTimer>
#include <QTimer>
#include "../widgets/SliderPlusBox.h"
#include <QButtonGroup>
#include <QToolButton>
#include <QComboBox>
#include "../../reader/JFJochReaderImage.h"

// Display toolbar: how the image is rendered — foreground (white-point) and background
// (black-point) sliders, auto-contrast, HDR (full dynamic range), and the colour map; at its right
// end the font size and the light/dark switch, which are also in the View menu but easy to miss there.
class JFJochViewerToolbarDisplay : public QToolBar {
    Q_OBJECT

    bool auto_foreground = false;

    SliderPlusBox *foreground_slider;
    SliderPlusBox *background_slider;
    // The background slider is rarely needed, so it is hidden unless this toggle (View menu) is on.
    // A non-zero black point switches it on, so an active background is never invisible.
    QAction *background_label_action;
    QAction *background_slider_action;
    QAction *show_background_action;
    QToolButton *auto_foreground_button;
    QToolButton *hdr_mode_button;
    QComboBox *color_map_select;
    QButtonGroup *font_zoom_group;   // three "A" buttons; the id is the zoom in per cent
    QToolButton *theme_button;       // light/dark switch; its tooltip names the theme it switches to
    void UpdateThemeButton();

    // A ctrl-wheel or auto-foreground burst reports a new foreground per event, and on a remote
    // display each slider update is a repaint of its own. Hold the readback to the remote
    // cadence; the tail run shows the final value. The background readback (held B + wheel)
    // gets the same treatment.
    void ApplyPendingForeground();
    float pending_foreground_ = 0.0f;
    QElapsedTimer foreground_rate_;
    QTimer *foreground_tail_timer_ = nullptr;
    void ApplyPendingBackground();
    float pending_background_ = 0.0f;
    QElapsedTimer background_rate_;
    QTimer *background_tail_timer_ = nullptr;
public:
    JFJochViewerToolbarDisplay(QWidget *parent = nullptr);

    // Current display settings, for persisting them across sessions (see JFJochViewerWindow).
    [[nodiscard]] int colorMap() const { return color_map_select->currentIndex(); }
    [[nodiscard]] bool autoForeground() const { return auto_foreground_button->isChecked(); }
    [[nodiscard]] bool hdrMode() const { return hdr_mode_button->isChecked(); }
    [[nodiscard]] bool backgroundSliderShown() const { return show_background_action->isChecked(); }
    [[nodiscard]] QAction *backgroundSliderAction() const { return show_background_action; }

signals:
    void setForeground(float val);
    void setBackground(float val);
    void colorMapChanged(int val);
    void setAutoForeground(bool val);
    void setHDRMode(bool val);
    void fontZoomSelected(int percent);

public slots:
    void updateForeground(float val);
    void updateBackground(float val);
    void updateAutoForeground(bool val);
    void updateColorMap(int val);
    void updateHDRMode(bool val);
    void showBackgroundSlider(bool val);
    void updateFontZoom(int percent);
    void imageLoaded(std::shared_ptr<const JFJochReaderImage> image);
private slots:
    void foregroundSet(double val);
    void backgroundSet(double val);
    void colorComboBoxSet(int val);
    void autoForegroundButtonPressed();
    void HDRModeButtonPressed();
};