#include "PanelsPanel.h"

#include <QLabel>
#include <QPainter>
#include <QPainterPath>
#include <QVBoxLayout>
#include <QtMath>

PanelsPanel::PanelsPanel(QWidget *parent) : QWidget(parent)
{
    auto *layout = new QVBoxLayout(this);
    layout->setContentsMargins(4, 4, 4, 4);

    m_statusLabel = new QLabel("Connect to load panels...", this);
    m_statusLabel->setAlignment(Qt::AlignHCenter | Qt::AlignTop);
    m_statusLabel->setStyleSheet("color: #888; font-style: italic;");
    layout->addWidget(m_statusLabel);
    layout->addStretch(1);

    setMinimumSize(200, 200);
}

void PanelsPanel::setRnpCount(int count)
{
    m_count = count;
    m_colors.clear();
    m_statusLabel->setText(count > 0
        ? QString("%1 panel%2").arg(count).arg(count == 1 ? "" : "s")
        : "No panels reported");
    update();
}

void PanelsPanel::setPanelColor(int index, const QColor &color)
{
    m_colors[index] = color;
    update();
}

void PanelsPanel::reset()
{
    m_count = 0;
    m_colors.clear();
    m_statusLabel->setText("Connect to load panels...");
    update();
}

void PanelsPanel::paintEvent(QPaintEvent *)
{
    if (m_count <= 0) return;

    QPainter p(this);
    p.setRenderHint(QPainter::Antialiasing, true);

    const QRectF bounds   = rect();
    const QRectF drawArea = bounds.adjusted(0, 28, 0, 0);
    const double side     = qMin(drawArea.width(), drawArea.height()) * 0.88;
    const double cx       = drawArea.center().x();
    const double cy       = drawArea.center().y();
    const double outerR   = side / 2.0;
    const double innerR   = outerR * 0.44;

    const QRectF outerRect(cx - outerR, cy - outerR, side,        side);
    const QRectF innerRect(cx - innerR, cy - innerR, innerR * 2,  innerR * 2);

    const double gapDeg  = (m_count > 1) ? 3.0 : 0.0;
    const double segSpan = (360.0 - m_count * gapDeg) / m_count;

    static const QColor kDefault(100, 140, 180);

    for (int i = 0; i < m_count; ++i) {
        const double startAngle = 90.0 - i * (segSpan + gapDeg);
        const double sweep      = -segSpan;

        QPainterPath path;
        path.arcMoveTo(outerRect, startAngle);
        path.arcTo(outerRect, startAngle, sweep);
        path.arcTo(innerRect, startAngle + sweep, -sweep);
        path.closeSubpath();

        p.setBrush(m_colors.value(i, kDefault));
        p.setPen(QPen(Qt::white, 2));
        p.drawPath(path);

        // Label at segment midpoint
        const double midAngle    = startAngle + sweep / 2.0;
        const double midAngleRad = qDegreesToRadians(midAngle);
        const double midR        = (outerR + innerR) / 2.0;
        const QPointF tc(cx + midR * qCos(midAngleRad),
                         cy - midR * qSin(midAngleRad));

        QFont font = p.font();
        font.setBold(true);
        font.setPointSize(qMax(7, qMin(12, static_cast<int>(outerR / (m_count * 0.55 + 2)))));
        p.setFont(font);
        p.setPen(Qt::white);
        p.drawText(QRectF(tc.x() - 22, tc.y() - 11, 44, 22), Qt::AlignCenter, QString::number(i));
    }

    // Centre hole: total count
    QFont cf = p.font();
    cf.setBold(true);
    cf.setPointSize(qMax(8, static_cast<int>(innerR * 0.45)));
    p.setFont(cf);
    p.setPen(palette().text().color());
    p.drawText(innerRect, Qt::AlignCenter, QString::number(m_count));
}