//
// Created by Krad on 2021/11/24.
//

#include "SlidePickerBox.h"
#include <QPainter>
#include <QMouseEvent>
#include <QLabel>
#include <QFont>
#include <qdebug.h>
const int fontSize = 80;
SlidePickerBox::SlidePickerBox(QWidget *parent):QWidget(parent) {
    this->setFixedHeight(360);

    QLabel* label = new QLabel(this);
    label->setText("1");
    label->setFixedHeight(110);
    label->setAlignment(Qt::AlignCenter);
    label->setObjectName("sliderPickerLabel");
    label->setFixedHeight(fontSize);
    label->setFixedWidth(320);
    QPoint p = this->mapToGlobal({this->contentsMargins().left(),50-fontSize/2});
    label->move(p);
    lbls.push_back(label);
    QLabel* label1 = new QLabel(this);
    label1->setText("2");
    label1->setFixedHeight(110);
    label1->setAlignment(Qt::AlignCenter);
    label1->setObjectName("sliderPickerLabel");
    label1->setFixedHeight(fontSize);
    label1->setFixedWidth(320);
    QPoint p1 = this->mapToGlobal({this->contentsMargins().left(),150-fontSize/2});
    label1->move(p1);
    lbls.push_back(label1);
    QLabel* label2 = new QLabel(this);
    label2->setText("3");
    label2->setFixedHeight(110);
    label2->setAlignment(Qt::AlignCenter);
    label2->setObjectName("sliderPickerLabel");
    label2->setFixedHeight(fontSize);
    label2->setFixedWidth(320);
    QPoint p2 = this->mapToGlobal({this->contentsMargins().left(),250-fontSize/2});
    label2->move(p2);
    lbls.push_back(label2);

    selectedLbl = label1;
    label1->setStyleSheet("color:white");
    label->setStyleSheet("background:transparent");
    label2->setStyleSheet("background:transparent" );
    QWidget* line1 = new QWidget(this);
    line1->setFixedSize(320,100);
    line1->setObjectName("topBottomLine");
    line1->raise();
    QPoint lp = this->mapToGlobal({this->contentsMargins().left(),100});
    line1->move(lp);

    selectedIndex = 1;
}

void SlidePickerBox::mousePressEvent(QMouseEvent * ev) {
    isDragging = true;
    o_x = ev->pos().x();
    o_y = ev->pos().y();
    QWidget::mousePressEvent( ev);
}

void SlidePickerBox::mouseMoveEvent(QMouseEvent *ev) {
    if(lbls.count()<2) return;
    if(isDragging)
    {
        int offset = (ev->pos().y()-o_y);
        //防止速度过快
        while(abs(offset)>50)
        {
            offset=offset/2;
        }
        //防止拉过头
        int selectItemCenter = selectedLbl->geometry().center().y();
        if (selectedLbl == lbls.last() && selectItemCenter<=150 && offset<0) return;
        if (selectedLbl == lbls.first() && selectItemCenter>=150 && offset>0) return;
        int i = 0;
        for (auto item : lbls)
        {
            //不需要横向
            //int nx = item->geometry().left()+(ev->pos().x()-o_x);
            int ny = item->geometry().top() + offset;

            item->move(item->geometry().left(),ny);
            int nc = item->geometry().center().y();

            if (nc<=200 && nc>100)
            {
                item->setStyleSheet("color:white");
                selectedLbl = item;
                selectedIndex = i;
            } else{
                item->setStyleSheet("background:transparent");
            }
            i++;
        }
        o_x = ev->pos().x();
        o_y = ev->pos().y();
        repaint();
    }
    QWidget::mouseMoveEvent(ev);
}

void SlidePickerBox::mouseReleaseEvent(QMouseEvent *ev) {
    isDragging = false;
    adjustPositon();
    QWidget::mouseReleaseEvent(ev);
}

void SlidePickerBox::adjustPositon() const {
    if (selectedLbl->geometry().center().y() != 150)
    {
        //选择完毕，选中项回归正位

        int offset = 150 - selectedLbl->geometry().center().y();
        for (auto item : lbls)
        {
            int ny = item->geometry().top()+offset;
            item->move(item->geometry().left(),ny);
        }
    }
}

void SlidePickerBox::paintEvent(QPaintEvent *ev) {
    QWidget::paintEvent(ev);
}

void SlidePickerBox::paintText(QString txt, int x, int y, const QColor& color) {
    QPainter painter(this);
    painter.setRenderHint(QPainter::TextAntialiasing, true);
    QFont f;
    f.setPixelSize(30);
    painter.setFont(f);
    painter.setPen(color);
    painter.drawText(x,y,txt);
}

void SlidePickerBox::setItems(QStringList itemsList) {
    this->items = itemsList;
    hideLabel(selectedLbl);
    hideLabel(prevLbl);
    hideLabel(nextLbl);
    for (auto item : lbls)
    {
        delete item;
    }
    selectedLbl = nullptr;
    prevLbl = nullptr;
    nextLbl = nullptr;
    lbls.clear();

    for (QString str : this->items)
    {
        QLabel* lbl = new QLabel(this);
        lbl->setText(str);
        lbl->setFixedHeight(110);
        lbl->setAlignment(Qt::AlignCenter);
        lbl->setObjectName("sliderPickerLabel");
        lbl->setFixedHeight(fontSize);
        lbl->setFixedWidth(320);
        lbls.push_back(lbl);
        QPoint p = this->mapToGlobal({this->contentsMargins().left(),-150});
        lbl->move(p);
    }
    selectedIndex = lbls.count()-1;
    setSelectedValue(this->items.last());
}

QString SlidePickerBox::getSelectedValue() {
    if (!selectedLbl) return "";
    return selectedLbl->text();
}

void SlidePickerBox::setCurrentLabel(QLabel *label) {
    if (selectedLbl)hideLabel(selectedLbl);
    if (label) {
        QPoint lp = this->mapToGlobal({this->contentsMargins().left(), 100});
        label->move(lp);
        label->show();
        selectedLbl = label;
    }
}

void SlidePickerBox::setNextLabel(QLabel *label) {
    if (nextLbl)hideLabel(nextLbl);
    if (label){
        QPoint lp = this->mapToGlobal({this->contentsMargins().left(),200});
        label->move(lp);
        label->show();
        nextLbl = label;
    }
}

void SlidePickerBox::setPrevLabel(QLabel *label) {
    if (prevLbl)hideLabel(prevLbl);
    if (label) {
        QPoint lp = this->mapToGlobal({this->contentsMargins().left(), 0});
        label->move(lp);
        label->show();
        prevLbl = label;
    }
}

void SlidePickerBox::hideLabel(QLabel *label) {
    if (!label) return;
    QPoint lp = this->mapToGlobal({this->contentsMargins().left(), -150});
    label->move(lp);
}

void SlidePickerBox::setSelectedValue(const QString& val) {
    qDebug()<<"set value:"<<val;
    for (int i = 0; i < lbls.count() ; ++i) {
        if(lbls[i]->text() == val) {
            selectedIndex = i;
            break;
        }
    }
    int first_y = -100 * (selectedIndex-1);
    for (int i = 0; i < lbls.count() ; ++i) {
        QPoint lp = {this->contentsMargins().left(), first_y+i*100};
        lbls[i]->move(lp);
        lbls[i]->show();
        lbls[i]->setStyleSheet("background:transparent");
        lbls[i]->lower();
    }
    selectedLbl = lbls[selectedIndex];
    lbls[selectedIndex]->setStyleSheet("color:white");
    adjustPositon();
}