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

#include "JFJochSimpleChartView.h"

#include <QMenu>
#include <QClipboard>
#include <QApplication>
#include <QCategoryAxis>

JFJochSimpleChartView::JFJochSimpleChartView(QWidget *parent)
        : QChartView(new QChart(), parent) {
    chart()->legend()->hide();
    setFixedHeight(200);
    setRenderHint(QPainter::Antialiasing);
    //setRubberBand(QChartView::RubberBand::HorizontalRubberBand);
}

void JFJochSimpleChartView::UpdateData(const std::vector<float> &in_x, const std::vector<float> &in_y, bool one_over_x) {
    x = in_x; y = in_y;
    chart()->removeAllSeries();
    // Remove all axes to avoid duplicates
    for (auto ax : chart()->axes()) chart()->removeAxis(ax);

    if (x.empty() || x.size() != y.size()) return;

    auto* series = new QLineSeries(this);
    for (size_t i = 0; i < x.size(); ++i) series->append(x[i], y[i]);
    chart()->addSeries(series);

    auto* axY = new QValueAxis();
    chart()->addAxis(axY, Qt::AlignLeft);
    series->attachAxis(axY);

    // Build X range
    auto [minXIt, maxXIt] = std::minmax_element(x.begin(), x.end());
    const double xmin = *minXIt, xmax = *maxXIt;

    if (one_over_x) {
        // Hidden X value axis on top for grid/range
        auto* axXTop = new QValueAxis();
        axXTop->setRange(xmin, xmax);
        axXTop->setTickCount(5);
        axXTop->setLabelsVisible(false);
        chart()->addAxis(axXTop, Qt::AlignTop);
        series->attachAxis(axXTop);

        // Visible category axis at bottom for 1/x labels
        auto* axXcat = new QCategoryAxis();
        axXcat->setLabelsPosition(QCategoryAxis::AxisLabelsPositionOnValue);
        axXcat->setGridLineVisible(false);
        axXcat->setMinorGridLineVisible(false);

        const int tickCount = axXTop->tickCount();
        const double step = (tickCount > 1) ? (xmax - xmin) / (tickCount - 1) : 0.0;
        for (int i = 0; i < tickCount; ++i) {
            const double xv = xmin + i * step;
            const QString lab = (std::abs(xv) < 1e-12)
                                ? QStringLiteral("∞")
                                : QString::number(1.0 / xv, 'g', 4);
            axXcat->append(lab, xv);
        }
        chart()->addAxis(axXcat, Qt::AlignBottom);
        series->attachAxis(axXcat);
    } else {
        // Normal value axis at bottom
        auto* axX = new QValueAxis();
        axX->setRange(xmin, xmax);
        chart()->addAxis(axX, Qt::AlignBottom);
        series->attachAxis(axX);
    }
}

void JFJochSimpleChartView::ClearData() {
    chart()->removeAllSeries();
}

void JFJochSimpleChartView::contextMenuEvent(QContextMenuEvent *event) {
    QMenu menu(this);
    QAction *copyXY = menu.addAction("Copy (x y) points");
    copyXY->setEnabled(!x.empty() && x.size() == y.size());

    QAction *chosen = menu.exec(event->globalPos());
    if (chosen == copyXY) {
        QString out;
        out.reserve(static_cast<int>(x.size() * 16)); // rough prealloc
        for (size_t i = 0; i < x.size() && i < y.size(); ++i) {
            out.append(QString::number(x[i], 'g', 10));
            out.append(' ');
            out.append(QString::number(y[i], 'g', 10));
            if (i + 1 < x.size()) out.append('\n');
        }
        QClipboard *cb = QApplication::clipboard();
        cb->setText(out);
    }
}

void JFJochSimpleChartView::applyInverseXLabels(QValueAxis* axX, QLineSeries* s) {
    axX->setTickCount(5); // adjust as needed
    axX->setLabelsVisible(false); // hide default numeric labels

    auto* axXcat = new QCategoryAxis();
    axXcat->setLabelsPosition(QCategoryAxis::AxisLabelsPositionOnValue);
    axXcat->setGridLineVisible(false);
    axXcat->setMinorGridLineVisible(false);

    const int tickCount = axX->tickCount();
    const double min = axX->min();
    const double max = axX->max();
    const double step = (tickCount > 1) ? (max - min) / (tickCount - 1) : 0.0;

    for (int i = 0; i < tickCount; ++i) {
        const double xv = min + i * step;
        if (std::abs(xv) < 1e-12) {
            axXcat->append("∞", xv);
        } else {
            const double inv = 1.0 / xv;
            axXcat->append(QString::number(inv, 'g', 4), xv);
        }
    }

    chart()->addAxis(axXcat, Qt::AlignBottom);
    s->attachAxis(axXcat);
}