#include "slider.h"

#include <QMouseEvent>
#include <QPainter>
#include <QDebug>

Slider::Slider(QWidget *parent) : QWidget(parent),
    isSliderDown_(false), sliderPosition_(0), value_(0), minimum_(0), maximum_(1)
{
    groove.load(":/images/slider/groove.png");
    sub.load(":/images/slider/humidity.png");
    handle.load(":/images/slider/handle_big.png");
    updatePixmapPosition();

}

void Slider::setSubPixmap(const QPixmap &pixmap)
{
    sub = pixmap;
}

void Slider::setSubPixmap(const QString &fileName)
{
    setSubPixmap(QPixmap(fileName));
}

void Slider::setRange(int min, int max)
{
    minimum_ = min;
    maximum_ = max;

    if (value_ < min)
        setValue(min);
    else if (value_ > max)
        setValue(max);
}

void Slider::setMinimum(int min)
{
    minimum_ = min;

    if (value_ < min)
        setValue(min);
}

void Slider::setMaximum(int max)
{
    maximum_ = max;

    if (value_ > max)
        setValue(max);
}

bool Slider::isSliderDown()
{
    return isSliderDown_;
}

int Slider::sliderPosition()
{
    return sliderPosition_;
}

void Slider::setSliderPosition(int value)
{
    if (sliderPosition_ == value)
        return;

    sliderPosition_ = value;

    emit sliderMoved(value);

    update();
}

void Slider::mouseMoveEvent(QMouseEvent *event)
{
    if (!isSliderDown_)
        return;

    setSliderPosition(calcSliderPosition(event->x()));
}

void Slider::mousePressEvent(QMouseEvent */*event*/)
{
    isSliderDown_ = true;
}

void Slider::mouseReleaseEvent(QMouseEvent */*event*/)
{
    isSliderDown_ = false;

    if (sliderPosition_ == value_)
        return;

    setValue(sliderPosition_);
}

void Slider::paintEvent(QPaintEvent */*event*/)
{
    QPainter painter(this);

    painter.drawPixmap(groovePoint, groove);

    int subLength = calcSubLength(sliderPosition_);
    if (subLength > 0)
        painter.drawPixmap(subPoint, sub, QRect(0, 0, subLength, sub.height()));

    QPen tickPen(QColor(71, 71, 71));
    tickPen.setWidth(2);
    painter.setPen(tickPen);
    foreach (int tick, ticks)
    {
        int x = subPoint.x() + calcSubLength(tick);
        painter.drawLine(x, groovePoint.y() + 22, x, groovePoint.y() + 28);
    }

    foreach (int tick, bigTicks)
    {
        int x = subPoint.x() + calcSubLength(tick);
        painter.drawLine(x, groovePoint.y() + 22, x, groovePoint.y() + 33);
    }

    QPoint handlePoint(subPoint.x() + subLength - handle.width() / 2, (height() - handle.height()) / 2);
    painter.drawPixmap(handlePoint, handle);
}

void Slider::resizeEvent(QResizeEvent */*event*/)
{
    updatePixmapPosition();
}

int Slider::calcSliderPosition(int mouseX)
{
    int x = qBound(grooveMin, mouseX, grooveMax);
    qreal pos = (qreal) (x - grooveMin) / (grooveMax - grooveMin) * (maximum_ - minimum_) + minimum_;
    return qRound(pos);
}

int Slider::calcSubLength(int value)
{
    return handle.width() / 4 + (sub.width() - handle.width() / 2) * (value - minimum_) / (maximum_ - minimum_);
}

void Slider::updatePixmapPosition()
{
    grooveMin = (width() - sub.width()) / 2;
    grooveMax = width() - grooveMin;

    groovePoint = QPoint((width() - groove.width()) / 2, (height() - groove.height()) / 2);
    subPoint = QPoint((width() - sub.width()) / 2, (height() - sub.height()) / 2);
}

void Slider::setValue(int value)
{
    if (value == value_)
        return;

    setSliderPosition(value);

    value_ = value;

    emit valueChanged(value);
}