#include "ProgressBar.h"
#include <QPainter>

ProgressBar::ProgressBar(const QVector<Tick>& tickList, QWidget *parent) : QWidget(parent), mTickList(tickList) {
    setAttribute(Qt::WA_OpaquePaintEvent, true);
    mTimer = startTimer(30);
}

double ProgressBar::getDrawWidth(double value) {
    int n = mTickList.size();
    int i = 1;
    for(; i < n - 1; ++i) {
        double cur = mTickList[i].mValue;
        if(mValue <  cur || qFuzzyCompare(mValue, cur)) {
            break;
        }
    }
    int lowerOffset = i - 1;
    int upperOffset = i;
    double lower = mTickList[lowerOffset].mValue;
    double upper = mTickList[upperOffset].mValue;
    double w_step = (double)QWidget::width()/(double)(n-1);
    double lastRate = qMax(0.0, (mValue - lower)/(upper - lower));
    double drawWidth = w_step * (lastRate + lowerOffset);
    QString ticks;
    for(Tick& tick : mTickList) {
        ticks.append("  " + QString::number(tick.mValue));
    }
    // qDebug() << QString("%1->[%2,%3]  i=%4 n=%5 drawWidth:%6 width:%7  ticks:%8   w_step:%9 lastRate:%10")
    // .arg(mValue).arg(lower).arg(upper).arg(i).arg(n).arg(drawWidth).arg(width()).arg(ticks)
    // .arg(w_step).arg(lastRate);
    return drawWidth;
}



void ProgressBar::paintEvent(QPaintEvent *event) {
    QPainter painter(this);
    painter.setPen(Qt::NoPen);
    painter.fillRect(rect(), QApplication::style()->standardPalette().brush(QPalette::Window));
    painter.setPen(QPen(Qt::black));
    auto w = (double)QWidget::width();
    auto hh = (double)height()/2;
    int n = mTickList.size();
    int tickW = 1;
    double drawWidth = getDrawWidth(mValue);
    // 背景
    painter.fillRect(0, 0, drawWidth - tickW - 4, height()/2, Qt::black);
    int curX = 0;
    // 进度条
    while(curX + tickW + 4 < drawWidth){
        painter.fillRect(curX, 0, tickW, height()/2, Qt::gray);
        curX += tickW + (int)mTickSpaceW;
    }
    int lineY = (int)hh + 2;
    painter.fillRect(curX -(int)mTickSpaceW , 0, 4, lineY  - 0, Qt::yellow);
    painter.drawLine(0, lineY , (int)w, lineY);
    // 画刻度
    QFont font;
    font.setBold(true);
    QFontMetrics fm(font);
    for(int i = 0; i < n; ++i){
        int tickX = (int)((double)(QWidget::width() * i)/(double)(n - 1));
        int textW = fm.horizontalAdvance( mTickList[i].mText);
        int textX;
        if(i == n - 1) {
            textX = tickX - textW;
            tickX -=1;
        } else if( i == 0) {
            textX = tickX;
        } else {
            textX = tickX - textW/2;
        }
        painter.setPen(Qt::black);
        painter.drawLine(tickX, lineY, tickX, (lineY + 5));
        painter.setPen(mTickList[i].mColor);
        painter.setFont(font);
        painter.drawText(QRectF(textX, lineY, textW, lineY), Qt::AlignCenter, mTickList[i].mText);
    }
}

void ProgressBar::timerEvent(QTimerEvent *event) {
    if(event->timerId() == mTimer) {
        if(mSetValue) mSetValue();
        update();
    }
    QObject::timerEvent(event);
}