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

#include "JFJochAzIntWindow.h"
#include <QGroupBox>
#include <QButtonGroup>
#include <QFormLayout>

JFJochAzIntWindow::JFJochAzIntWindow(
        const AzimuthalIntegrationSettings &settings,
        QWidget *parent)
    : JFJochHelperWindow(parent),
      m_settings(settings)
{
    setWindowTitle("Azimuthal integration settings");
    QWidget *centralWidget = new QWidget(this);
    setCentralWidget(centralWidget);

    auto mainLayout = new QVBoxLayout(centralWidget);

    // Group box similar to TS Paper + stacked inputs
    auto group = new QGroupBox("Azimuthal integration", this);
    auto formLayout = new QFormLayout(group);

    // Q spacing
    m_qSpacing = new SliderPlusBox(0.01, 1.0, 0.001, 3, this);
    m_qSpacing->setValue(m_settings.GetQSpacing_recipA());
    formLayout->addRow(tr("Q spacing [Å⁻¹]:"), m_qSpacing);

    // Low Q
    m_lowQ = new SliderPlusBox(0.001, 10.0, 0.001, 3, this);
    m_lowQ->setValue(m_settings.GetLowQ_recipA());
    formLayout->addRow(tr("Low Q [Å⁻¹]:"), m_lowQ);

    // High Q
    m_highQ = new SliderPlusBox(0.001, 10.0, 0.001, 3, this);
    m_highQ->setValue(m_settings.GetHighQ_recipA());
    formLayout->addRow(tr("High Q [Å⁻¹]:"), m_highQ);

    // Solid angle / polarization correction checkboxes
    m_solidAngleCheckBox = new QCheckBox(tr("Solid angle correction"), this);
    m_solidAngleCheckBox->setChecked(m_settings.IsSolidAngleCorrection());
    formLayout->addRow(QString(), m_solidAngleCheckBox);

    m_polarizationCheckBox = new QCheckBox(tr("Polarization correction"), this);
    m_polarizationCheckBox->setChecked(m_settings.IsPolarizationCorrection());
    formLayout->addRow(QString(), m_polarizationCheckBox);

    // Azimuthal bins (radio buttons like TS frontend)
    auto azimGroupBox = new QGroupBox(tr("Azimuthal bins"), this);
    auto azimLayout   = new QHBoxLayout(azimGroupBox);
    m_azimuthalBinsGroup = new QButtonGroup(this);

    const QList<int> binOptions = {1, 2, 4, 8, 16, 32, 64, 128};
    const int currentBins = m_settings.GetAzimuthalBinCount();

    for (int bins : binOptions) {
        auto *btn = new QRadioButton(QString::number(bins), azimGroupBox);
        m_azimuthalBinsGroup->addButton(btn, bins);
        m_azimuthalBinButtons.push_back(btn);
        azimLayout->addWidget(btn);
        if (bins == currentBins) {
            btn->setChecked(true);
        }
    }

    group->setLayout(formLayout);
    mainLayout->addWidget(group);
    mainLayout->addWidget(azimGroupBox);

    // Error label at bottom (no buttons)
    m_errorLabel = new QLabel(this);
    m_errorLabel->setStyleSheet("color: rgb(200, 0, 0);"); // red-ish text for errors
    m_errorLabel->setWordWrap(true);
    mainLayout->addWidget(m_errorLabel);

    // Connections – on change, update errors, settings, and emit
    connect(m_qSpacing, &SliderPlusBox::valueChanged, [this](double val) {
        m_qSpacingError = (val < 0.01);
        Update();
    });

    connect(m_lowQ, &SliderPlusBox::valueChanged, [this](double val) {
        m_lowQError = (val < 0.001 || val > 10.0);
        Update();
    });

    connect(m_highQ, &SliderPlusBox::valueChanged, [this](double val) {
        m_highQError = (val < 0.001 || val > 10.0);
        Update();
    });

    connect(m_solidAngleCheckBox, &QCheckBox::toggled, [this](bool /*checked*/) {
        Update();
    });

    connect(m_polarizationCheckBox, &QCheckBox::toggled, [this](bool /*checked*/) {
        Update();
    });

    connect(m_azimuthalBinsGroup,
            QOverload<QAbstractButton *>::of(&QButtonGroup::buttonClicked),
            [this](QAbstractButton * /*btn*/) {
                Update();
            });

    Update();
}


void JFJochAzIntWindow::UpdateErrorLabel() {
    const double lowQ  = m_lowQ->value();
    const double highQ = m_highQ->value();

    QStringList messages;

    if (m_qSpacingError) {
        messages << tr("Q spacing must be ≥ 0.01 Å⁻¹.");
    }
    if (m_lowQError) {
        messages << tr("Low Q must be between 0.001 and 10 Å⁻¹.");
    }
    if (m_highQError) {
        messages << tr("High Q must be between 0.001 and 10 Å⁻¹.");
    }
    if (highQ <= lowQ) {
        messages << tr("High Q must be greater than Low Q.");
    }

    if (messages.isEmpty()) {
        m_errorLabel->clear();
    } else {
        m_errorLabel->setText(messages.join(' '));
    }
}

void JFJochAzIntWindow::ApplyToSettings() {
    const float lowQ     = static_cast<float>(m_lowQ->value());
    const float highQ    = static_cast<float>(m_highQ->value());
    const float qSpacing = static_cast<float>(m_qSpacing->value());

    m_settings.SolidAngleCorrection(m_solidAngleCheckBox->isChecked());
    m_settings.PolarizationCorrection(m_polarizationCheckBox->isChecked());
    m_settings.QRange_recipA(lowQ, highQ);
    m_settings.QSpacing_recipA(qSpacing);

    const int bins = m_azimuthalBinsGroup->checkedId();
    if (bins > 0) {
        m_settings.AzimuthalBinCount(bins);
    }
}

void JFJochAzIntWindow::Update() {
    // Update error label first
    UpdateErrorLabel();

    // If there are validation errors, do not update settings / emit
    const double lowQ  = m_lowQ->value();
    const double highQ = m_highQ->value();
    const bool rangeError = (highQ <= lowQ);
    const bool anyError   = m_lowQError || m_highQError || m_qSpacingError || rangeError;

    if (anyError)
        return;

    // Update internal settings from widgets
    ApplyToSettings();

    // Emit updated settings when valid
    emit settingsChanged(m_settings);
}