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

#include "JFJochViewerToolbarDisplay.h"
#include "../ViewerTheme.h"
#include <QLabel>
#include "../../common/ColorScale.h"
#include "../RemoteDisplayMode.h"
#include "../widgets/ToolbarIcons.h"

constexpr double MAX_SLIDER_NO_IMAGE = 65000;

JFJochViewerToolbarDisplay::JFJochViewerToolbarDisplay(QWidget *parent)
    : QToolBar(parent) {
    setWindowTitle("Display");   // shown in the toolbar/dock context menu

    foreground_tail_timer_ = new QTimer(this);
    foreground_tail_timer_->setSingleShot(true);
    connect(foreground_tail_timer_, &QTimer::timeout,
            this, &JFJochViewerToolbarDisplay::ApplyPendingForeground);

    background_tail_timer_ = new QTimer(this);
    background_tail_timer_->setSingleShot(true);
    connect(background_tail_timer_, &QTimer::timeout,
            this, &JFJochViewerToolbarDisplay::ApplyPendingBackground);

    // Two sliders share the strip, so each is capped rather than expanding across the window.
    const int slider_cap = fontMetrics().averageCharWidth() * 36;

    addWidget(new QLabel(" Foreground  ", this));

    foreground_slider = new SliderPlusBox(1, MAX_SLIDER_NO_IMAGE, 1.0, 1, this,
                                          SliderPlusBox::ScaleType::Logarithmic);
    foreground_slider->setValue(10);
    foreground_slider->setToolTip("White point of the color map (image contrast); hold F and use"
                                  " the mouse wheel, Ctrl+wheel for coarse steps");
    SetThemedStyleSheet(foreground_slider, SliderStyle);
    foreground_slider->setMaximumWidth(slider_cap);
    addWidget(foreground_slider);

    addWidget(new QLabel("   Background  ", this));

    background_slider = new SliderPlusBox(0, MAX_SLIDER_NO_IMAGE, 1.0, 1, this,
                                          SliderPlusBox::ScaleType::Logarithmic);
    background_slider->setValue(0);
    background_slider->setToolTip("Black point of the color map (0 = off); hold B and use"
                                  " the mouse wheel");
    SetThemedStyleSheet(background_slider, SliderStyle);
    background_slider->setMaximumWidth(slider_cap);
    addWidget(background_slider);

    auto makeToggle = [this](const QString &text, const QString &tip) {
        auto *b = new QToolButton(this);
        b->setText(text);
        b->setToolButtonStyle(Qt::ToolButtonTextOnly);
        b->setCheckable(true);
        b->setToolTip(tip);
        b->setCursor(Qt::PointingHandCursor);
        SetThemedStyleSheet(b, ToolbarIcons::buttonStyle);
        return b;
    };
    auto_foreground_button = makeToggle("Auto", "Auto-contrast to the current image");
    addWidget(auto_foreground_button);
    hdr_mode_button = makeToggle("HDR", "High dynamic range: show the full intensity range unclipped");
    addWidget(hdr_mode_button);

    addWidget(new QLabel("   Color map  ", this));

    // Initialize QComboBox with the options
    color_map_select = new QComboBox(this);
    color_map_select->addItem("Indigo", static_cast<int>(ColorScaleEnum::Indigo));
    color_map_select->addItem("Viridis", static_cast<int>(ColorScaleEnum::Viridis));
    color_map_select->addItem("Magma", static_cast<int>(ColorScaleEnum::Magma));
    color_map_select->addItem("Inferno", static_cast<int>(ColorScaleEnum::Inferno));
    color_map_select->addItem("Heat", static_cast<int>(ColorScaleEnum::Heat));
    color_map_select->addItem("Black on white", static_cast<int>(ColorScaleEnum::BW));
    color_map_select->addItem("White on black", static_cast<int>(ColorScaleEnum::WB));
    color_map_select->addItem("Green", static_cast<int>(ColorScaleEnum::Green));

    color_map_select->setCurrentIndex(static_cast<int>(ColorScaleEnum::Indigo));
    addWidget(color_map_select);

    connect(foreground_slider, &SliderPlusBox::valueChanged, this, &JFJochViewerToolbarDisplay::foregroundSet);
    connect(background_slider, &SliderPlusBox::valueChanged, this, &JFJochViewerToolbarDisplay::backgroundSet);
    connect(color_map_select, QOverload<int>::of(&QComboBox::currentIndexChanged),
            this, &JFJochViewerToolbarDisplay::colorComboBoxSet);
    connect(auto_foreground_button, &QToolButton::clicked, this, &JFJochViewerToolbarDisplay::autoForegroundButtonPressed);
    connect(hdr_mode_button, &QToolButton::clicked, this, &JFJochViewerToolbarDisplay::HDRModeButtonPressed);
    auto *stretch = new QWidget(this);
    stretch->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Preferred);
    addWidget(stretch);

    auto makeIconButton = [this](const QIcon &icon, const QString &tip, bool checkable) {
        auto *b = new QToolButton(this);
        b->setIcon(icon);
        b->setIconSize(QSize(20, 20));
        b->setToolTip(tip);
        b->setCheckable(checkable);
        b->setCursor(Qt::PointingHandCursor);
        SetThemedStyleSheet(b, ToolbarIcons::buttonStyle);
        return b;
    };
    font_zoom_group = new QButtonGroup(this);
    font_zoom_group->setExclusive(true);
    for (int step = 0; step < 3; step++) {
        const int percent = 100 + 25 * step;
        auto *b = makeIconButton(ToolbarIcons::letterA(step), QString("Font size %1 %").arg(percent), true);
        font_zoom_group->addButton(b, percent);
        addWidget(b);
    }
    connect(font_zoom_group, &QButtonGroup::idClicked, this, &JFJochViewerToolbarDisplay::fontZoomSelected);
    addSeparator();

    theme_button = makeIconButton(ToolbarIcons::halfSun(), QString(), false);
    addWidget(theme_button);
    connect(theme_button, &QToolButton::clicked, this,
            [] { SetThemeChoice(DarkTheme() ? ThemeChoice::Light : ThemeChoice::Dark); });
    connect(ThemeNotifier::Instance(), &ThemeNotifier::changed, this, &JFJochViewerToolbarDisplay::UpdateThemeButton);
    UpdateThemeButton();
}

void JFJochViewerToolbarDisplay::UpdateThemeButton() {
    theme_button->setToolTip(DarkTheme() ? "Switch to the light theme" : "Switch to the dark theme");
}

void JFJochViewerToolbarDisplay::updateFontZoom(int percent) {
    if (auto *b = font_zoom_group->button(percent))
        b->setChecked(true);
}

void JFJochViewerToolbarDisplay::foregroundSet(double val) {
    emit setForeground(static_cast<float>(val));
}

void JFJochViewerToolbarDisplay::backgroundSet(double val) {
    emit setBackground(static_cast<float>(val));
}

void JFJochViewerToolbarDisplay::updateBackground(float val) {
    pending_background_ = val;
    if (RemoteDisplayMode() && background_rate_.isValid()
        && background_rate_.elapsed() < kRemoteRepaintIntervalMs) {
        background_tail_timer_->start(kRemoteRepaintIntervalMs);
        return;
    }
    background_tail_timer_->stop();
    ApplyPendingBackground();
}

void JFJochViewerToolbarDisplay::ApplyPendingBackground() {
    background_rate_.restart();
    QSignalBlocker blocker(background_slider);
    background_slider->setValue(pending_background_);
}

void JFJochViewerToolbarDisplay::updateForeground(float val) {
    pending_foreground_ = val;
    if (RemoteDisplayMode() && foreground_rate_.isValid()
        && foreground_rate_.elapsed() < kRemoteRepaintIntervalMs) {
        foreground_tail_timer_->start(kRemoteRepaintIntervalMs);
        return;
    }
    foreground_tail_timer_->stop();
    ApplyPendingForeground();
}

void JFJochViewerToolbarDisplay::ApplyPendingForeground() {
    foreground_rate_.restart();
    QSignalBlocker blocker(foreground_slider);
    foreground_slider->setValue(pending_foreground_);
}

void JFJochViewerToolbarDisplay::colorComboBoxSet(int val) {
    emit colorMapChanged(val);
}

void JFJochViewerToolbarDisplay::autoForegroundButtonPressed() {
    emit setAutoForeground(auto_foreground_button->isChecked());
}

void JFJochViewerToolbarDisplay::updateAutoForeground(bool val) {
    QSignalBlocker blocker(auto_foreground_button);
    auto_foreground_button->setChecked(val);
}

void JFJochViewerToolbarDisplay::updateColorMap(int val) {
    QSignalBlocker blocker(color_map_select);
    color_map_select->setCurrentIndex(val);
}

void JFJochViewerToolbarDisplay::updateHDRMode(bool val) {
    QSignalBlocker blocker(hdr_mode_button);
    hdr_mode_button->setChecked(val);
}

void JFJochViewerToolbarDisplay::HDRModeButtonPressed() {
    emit setHDRMode(hdr_mode_button->isChecked());
}

void JFJochViewerToolbarDisplay::imageLoaded(std::shared_ptr<const JFJochReaderImage> image) {
    if (image) {
        auto valid = image->ValidMinMax();
        if (valid.has_value() && valid->second > 1) {
            foreground_slider->setMax(valid->second);
            background_slider->setMax(valid->second);
        } else {
            foreground_slider->setMax(MAX_SLIDER_NO_IMAGE);
            background_slider->setMax(MAX_SLIDER_NO_IMAGE);
        }
    } else {
        foreground_slider->setMax(MAX_SLIDER_NO_IMAGE);
        background_slider->setMax(MAX_SLIDER_NO_IMAGE);
    }
}