#include <QPainter>
#include <QStringList>
#include "font.h"
#include "sliderinfoitem.h"

#define SIZE 5

SliderInfoItem::SliderInfoItem(QGraphicsItem *parent) : QGraphicsItem(parent)
{
    _side = Right;
    _color = Qt::red;

    _font.setPixelSize(FONT_SIZE);
    _font.setFamily(FONT_FAMILY);
}

void SliderInfoItem::updateBoundingRect()
{
    QFontMetrics fm(_font);
    qreal width;
    qreal height;

    if (_yLines.size() > 1) {
        width = (qreal)fm.boundingRect(_x).width();
        for (int i = 0; i < _yLines.size(); i++)
            width = qMax(width, (qreal)fm.boundingRect(_yLines.at(i)).width());
        height = (_yLines.size() + 1) * fm.height() - 2*fm.descent();
    } else {
        width = qMax(fm.boundingRect(_x).width(),
                     fm.boundingRect(_y).width());
        height = 2 * fm.height() - 2*fm.descent();
    }

    _boundingRect = (_side == Right)
                        ? QRectF(-SIZE/2, -height/2, width + 1.5*SIZE, height)
                        : QRectF(-(width + SIZE), -height/2, width + 1.5*SIZE, height);
}

void SliderInfoItem::paint(QPainter *painter, const QStyleOptionGraphicsItem
                                                  *option, QWidget *widget)
{
    Q_UNUSED(option);
    Q_UNUSED(widget);
    QFontMetrics fm(_font);

    painter->setFont(_font);
    painter->setRenderHint(QPainter::Antialiasing, false);

    QColor bc(painter->background().color());
    bc.setAlpha(196);

    if (_yLines.size() > 1) {
        int lineCount = _yLines.size();
        qreal totalHeight = (lineCount + 1) * fm.height() - 2*fm.descent();
        qreal width = (qreal)fm.boundingRect(_x).width();
        for (int i = 0; i < lineCount; i++)
            width = qMax(width, (qreal)fm.boundingRect(_yLines.at(i)).width());

        qreal xLeft = (_side == Right) ? SIZE : -(width + SIZE);
        qreal yTop = -totalHeight / 2;

        painter->setPen(Qt::NoPen);
        painter->setBrush(QBrush(bc));
        painter->drawRect(QRectF(xLeft, yTop, width, totalHeight));
        painter->setBrush(Qt::NoBrush);

        painter->setPen(_color);
        for (int i = 0; i < lineCount; i++) {
            qreal textY = yTop + (i + 1) * fm.height() - fm.descent();
            painter->drawText(QPointF(xLeft, textY), _yLines.at(i));
        }

        qreal xTextY = yTop + (lineCount + 1) * fm.height() - fm.descent();
        painter->drawText(QPointF(xLeft, xTextY), _x);
    } else {
        qreal width = qMax(fm.boundingRect(_x).width(),
                           fm.boundingRect(_y).width());
        QRectF rx, ry;

        if (_side == Right) {
            ry = QRectF(SIZE, -fm.height() + fm.descent(),
                        fm.boundingRect(_y).width(), fm.height() - fm.descent());
            rx = QRectF(SIZE, 0, fm.boundingRect(_x).width(),
                        fm.height() - fm.descent());
        } else {
            ry = QRectF(-(width + SIZE), -fm.height() + fm.descent(),
                        fm.boundingRect(_y).width(), fm.height() - fm.descent());
            rx = QRectF(-(width + SIZE), 0, fm.boundingRect(_x).width(),
                        fm.height() - fm.descent());
        }

        painter->setPen(Qt::NoPen);
        painter->setBrush(QBrush(bc));
        painter->drawRect(ry);
        painter->drawRect(rx);
        painter->setBrush(Qt::NoBrush);

        painter->setPen(_color);
        if (_side == Right) {
            painter->drawText(SIZE, -fm.descent()/2, _y);
            painter->drawText(SIZE, fm.height() - fm.descent()*1.5, _x);
        } else {
            painter->drawText(-(width + SIZE), -fm.descent()/2, _y);
            painter->drawText(-(width + SIZE),
                              fm.height() - fm.descent()*1.5, _x);
        }
    }

    painter->drawLine(QPointF(-SIZE/2, 0), QPointF(SIZE/2, 0));

    //painter->drawRect(boundingRect());
}

void SliderInfoItem::setText(const QString &x, const QString &y)
{
    prepareGeometryChange();
    _x = x; _y = y;
    _yLines.clear();
    updateBoundingRect();
}

void SliderInfoItem::setText(const QString &x, const QStringList &yLines)
{
    prepareGeometryChange();
    _x = x;
    _y = yLines.isEmpty() ? QString() : yLines.first();
    _yLines = yLines;
    updateBoundingRect();
}

void SliderInfoItem::setSide(Side side)
{
    if (side == _side)
        return;

    prepareGeometryChange();
    _side = side;
    updateBoundingRect();
}

void SliderInfoItem::setColor(const QColor &color)
{
    _color = color;
    update();
}