// tabbar.cpp - CONTROLLER 1 / 2 / 3 tabs (see tabbar.h)

#include "tabbar.h"

#include "style.h"

#include <QMouseEvent>
#include <QPainter>

#include <algorithm>

namespace {

const int BarH = 46;       // height of the bar
const int TabW = 200;      // tab width (less when the window is narrow)
const int Gap = 10;        // between the tabs
const int DotR = 7;        // link dot radius

QColor dotColour(AdvCtrl::ControllerLink::State state)
{
    switch (state) {
    case AdvCtrl::ControllerLink::Link:   return Style::Green;
    case AdvCtrl::ControllerLink::NoLink: return Style::LedOn;
    default:                              return Style::Grey;
    }
}

} // namespace

TabBar::TabBar(int count, QWidget *parent)
    : QWidget(parent)
{
    for (int i = 0; i < count; ++i)
        m_states.append(AdvCtrl::ControllerLink::Closed);
    setFixedHeight(BarH);
}

void TabBar::setActive(int index)
{
    m_active = index;
    update();
}

void TabBar::setState(int index, AdvCtrl::ControllerLink::State state)
{
    if (index < 0 || index >= m_states.size())
        return;
    m_states[index] = state;
    update();
}

QRectF TabBar::tabRect(int index) const
{
    const int n = int(m_states.size());
    const double w = std::max(width(), 1);
    const double tabW = std::min<double>(TabW, std::max(90.0, (w - (n - 1) * Gap) / n));
    const double x = (w - (n * tabW + (n - 1) * Gap)) / 2;
    return QRectF(x + index * (tabW + Gap), 4, tabW, BarH - 8);
}

void TabBar::paintEvent(QPaintEvent *)
{
    QPainter painter(this);
    painter.setRenderHint(QPainter::Antialiasing);
    painter.fillRect(rect(), Style::Background);

    QFont font(QStringLiteral("Arial"));
    font.setStyleHint(QFont::SansSerif);
    font.setBold(true);
    font.setPointSize(11);
    painter.setFont(font);

    for (int i = 0; i < m_states.size(); ++i) {
        const bool active = (i == m_active);
        const QRectF r = tabRect(i);
        painter.setPen(QPen(active ? Style::Line : Style::Grey, active ? 2 : 1));
        painter.setBrush(active ? Style::TabActive : Style::Panel);
        painter.drawRect(r);
        if (active)
            painter.fillRect(QRectF(r.left(), r.bottom() - 2, r.width(), 4), Style::Line);

        const double cy = r.center().y();
        painter.setPen(Qt::NoPen);
        painter.setBrush(dotColour(m_states.at(i)));
        painter.drawEllipse(QPointF(r.left() + 16 + DotR, cy), DotR, DotR);

        painter.setPen(active ? QColor(Qt::white) : Style::Text);
        const QRectF textRect(r.left() + 16 + 2 * DotR + 12, r.top(), r.width() - (16 + 2 * DotR + 12), r.height());
        painter.drawText(textRect, Qt::AlignLeft | Qt::AlignVCenter, QStringLiteral("CONTROLLER %1").arg(i + 1));
    }
}

void TabBar::mousePressEvent(QMouseEvent *event)
{
    if (event->button() != Qt::LeftButton)
        return;
    for (int i = 0; i < m_states.size(); ++i) {
        if (tabRect(i).contains(event->position())) {
            emit selected(i);
            return;
        }
    }
}