#include "ImageWidget.h"
#include "ui_ImageWidget.h"
#include <QPainter>
#include <QDebug>
ImageWidget::ImageWidget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::ImageWidget)
{
    ui->setupUi(this);
}

ImageWidget::~ImageWidget()
{
    delete ui;
}

void ImageWidget::setPixmap(const QPixmap& newPixmap) {
    this->pixmap = newPixmap;
    imageOffset = QPoint(0, 0); // 重置图片偏移量为(0, 0)
    setCursor(Qt::ArrowCursor);
    update(); // 触发重绘
}
void ImageWidget::setPixmapAndPoint(const QPixmap& pixmap, double previousScaleFactor, qreal scaleFactor, QPoint mousePos) {
    this->pixmap = pixmap;
    QPointF imagePos = (mousePos - imageOffset) / previousScaleFactor;
    imageOffset = mousePos - imagePos * scaleFactor;
    update();
}
void ImageWidget::clearPixmap() {
    this->pixmap = QPixmap(); // 将 pixmap 设置为空
    update(); // 触发重绘
}
void ImageWidget::paintEvent(QPaintEvent *event) 
{
    QPainter painter(this);
    if (!pixmap.isNull())
    {
        // 限制图片偏移量，确保图片不会被拖动到视图外
        int pixmapWidth = pixmap.width();
        int pixmapHeight = pixmap.height();
        int widgetWidth = width();
        int widgetHeight = height();

        // 限制横向偏移量，确保图片不会超出左边或右边
        if (pixmapWidth < widgetWidth)
        {
            imageOffset.setX(0); // 如果图片宽度小于控件宽度，居中显示
        } 
        else 
        {
            // 图片左边界不能超出控件左边，右边界不能超出控件右边
            imageOffset.setX(qMin(0.0, qMax(static_cast<qreal>(widgetWidth - pixmapWidth), imageOffset.x())));
        }

        // 限制纵向偏移量，确保图片不会超出上边或下边
        if (pixmapHeight < widgetHeight)
        {
            imageOffset.setY(0); // 如果图片高度小于控件高度，居中显示
        } 
        else 
        {
            // 图片上边界不能超出控件上边，下边界不能超出控件下边
            imageOffset.setY(qMin(0.0, qMax(static_cast<qreal>(widgetHeight - pixmapHeight), imageOffset.y())));
        }
        painter.drawPixmap(imageOffset.x(), imageOffset.y(), pixmap);

        QRect targetRect = { 476,476,476,476 };
        if (m_nSingleCameraOperationWnd)
        {
            targetRect = { 794,794,794,794 };
        }

        drawCross(&painter, targetRect);
        //DrawCrossWithScale(&painter, pixmapWidth, pixmapHeight, { 476,300 }, { 300,300 });
    }
}

void ImageWidget::mousePressEvent(QMouseEvent *event) {
    if (event->button() == Qt::LeftButton) {
        lastMousePos = event->pos(); // 记录鼠标按下时的位置
        isDragging = true; // 设置正在拖动的标志
        setCursor(Qt::OpenHandCursor);
    }
}

void ImageWidget::mouseMoveEvent(QMouseEvent *event) {
    if (isDragging && (event->buttons() & Qt::LeftButton)) {
        QPoint delta = event->pos() - lastMousePos; // 计算鼠标移动的偏移量
        imageOffset += delta; // 更新图片的偏移量
        lastMousePos = event->pos(); // 更新鼠标位置
        update();
    }
}

void ImageWidget::mouseReleaseEvent(QMouseEvent *event) {
    if (event->button() == Qt::LeftButton) {
        isDragging = false; // 重置正在拖动的标志
        setCursor(Qt::ArrowCursor);
    }
}
void ImageWidget::mouseDoubleClickEvent(QMouseEvent *event){
    if (event->type() == QEvent::MouseButtonDblClick) {
        // 恢复原始图像
        sendDoubleClicksignal();
    }
    QWidget::mouseDoubleClickEvent(event);
}

void ImageWidget::DrawCrossWithScale(QPainter* painter, double dImgWidth, double dImgHeight, const QSize& sourceImageSize, const QPointF& sourceImagePosition)
{
    QPen pen;
    pen.setWidth(1);
    pen.setBrush(Qt::yellow);
    painter->setPen(pen);

    const double drX = dImgWidth / 2;
    const double drY = dImgHeight / 2;
    const int nLineSpace = 20;
    const int shortLineLen = 15;
    const int longLineLen = 35;

    // 计算缩放比例
    double power = 1.0;
    auto drawLines = [&, power](double start, double end, int step, bool horizontal) {
        for (int i = 0; ; ++i) { // 使用无限循环，并通过条件跳出
            int increase = i * nLineSpace;
            if (increase > std::abs(end)) break; // 检查是否超过边界

            int lineLength = (i % 5 == 0 && i != 0) ? longLineLen : shortLineLen;

            QPointF ptX1, ptY1, ptX2, ptY2;

            if (horizontal) {
                // Horizontal lines
                ptX1 = QPointF((start + increase - sourceImagePosition.x()) * power, (drY - lineLength - sourceImagePosition.y()) * power);
                ptY1 = QPointF((start + increase - sourceImagePosition.x()) * power, (drY + lineLength - sourceImagePosition.y()) * power);

                ptX2 = QPointF((start - increase - sourceImagePosition.x()) * power, (drY - lineLength - sourceImagePosition.y()) * power);
                ptY2 = QPointF((start - increase - sourceImagePosition.x()) * power, (drY + lineLength - sourceImagePosition.y()) * power);
            }
            else {
                // Vertical lines
                ptX1 = QPointF((drX - lineLength - sourceImagePosition.x()) * power, (start + increase - sourceImagePosition.y()) * power);
                ptY1 = QPointF((drX + lineLength - sourceImagePosition.x()) * power, (start + increase - sourceImagePosition.y()) * power);

                ptX2 = QPointF((drX - lineLength - sourceImagePosition.x()) * power, (start - increase - sourceImagePosition.y()) * power);
                ptY2 = QPointF((drX + lineLength - sourceImagePosition.x()) * power, (start - increase - sourceImagePosition.y()) * power);
            }

            painter->drawLine(ptX1, ptY1);
            painter->drawLine(ptX2, ptY2);
        }
    };

    // Draw the cross with scale on both sides of the center
    drawLines(dImgWidth / 2.0, dImgWidth, nLineSpace, true);  // Right and Left side
    drawLines(dImgHeight / 2.0, dImgHeight, nLineSpace, false); // Top and Bottom side
}

void ImageWidget::drawCross(QPainter* painter, QRect rect)
{
    QPen pen;
    pen.setWidth(3);
    pen.setBrush(Qt::yellow);
    painter->setPen(pen);
    painter->drawLine(rect.width() / 2, 0, rect.width() / 2, rect.height());
    painter->drawLine(0, rect.height() / 2, rect.width(), rect.height() / 2);
}