screencapture.cpp

#include "screencapture.h"
#include <QApplication>
#include <QScreen>
#include <QKeyEvent>
#include <QDateTime>

ScreenCapture::ScreenCapture(QWidget *parent) : QWidget(parent), isCapturing(false), isCloseButtonHovered(false)
{
    // 设置窗口属性 - 确保完全覆盖屏幕且在最顶层
    setWindowFlags(Qt::FramelessWindowHint | Qt::WindowStaysOnTopHint | Qt::Tool | Qt::X11BypassWindowManagerHint);
    setAttribute(Qt::WA_TranslucentBackground);
    setAttribute(Qt::WA_NoSystemBackground);
    setMouseTracking(true);
    
    // 获取全屏截图 - 冻结屏幕
    QScreen *screen = QApplication::primaryScreen();
    qreal screenScale = screen->devicePixelRatio();
    
    // 获取全屏截图并设置正确的设备像素比例
    fullScreen = screen->grabWindow(0);
    fullScreen.setDevicePixelRatio(screenScale); // 显式告诉 QPixmap 它的比例
    
    // 获取屏幕几何信息并设置窗口大小
    QRect screenGeometry = screen->geometry();
    resize(screenGeometry.size());
    move(screenGeometry.topLeft());
    
    // 初始化关闭按钮区域
    closeButtonRect = QRect(width() - 50, 10, 40, 40);
    
    // 显示窗口 - 全屏蒙层
    showFullScreen();
    raise();
    activateWindow();
    
    qDebug() << "屏幕几何信息:" << screenGeometry;
    qDebug() << "屏幕缩放比例:" << screenScale;
    qDebug() << "截图尺寸:" << fullScreen.size();
    qDebug() << "截图设备像素比例:" << fullScreen.devicePixelRatio();
    qDebug() << "窗口尺寸:" << size();
    qDebug() << "窗口位置:" << pos();
}

ScreenCapture::~ScreenCapture()
{
}

void ScreenCapture::mousePressEvent(QMouseEvent *event)
{
    if (event->button() == Qt::LeftButton) {
        // 检查是否点击了关闭按钮
        if (closeButtonRect.contains(event->pos())) {
            emit captureCanceled();
            close();
            return;
        }
        
        startPoint = event->pos();
        captureRect.setTopLeft(startPoint);
        isCapturing = true;
    }
}

void ScreenCapture::mouseMoveEvent(QMouseEvent *event)
{
    if (isCapturing) {
        captureRect.setBottomRight(event->pos());
        update();
    }
    
    // 检测关闭按钮的悬停状态
    bool wasHovered = isCloseButtonHovered;
    isCloseButtonHovered = closeButtonRect.contains(event->pos());
    if (wasHovered != isCloseButtonHovered) {
        update(closeButtonRect);
    }
}

void ScreenCapture::mouseReleaseEvent(QMouseEvent *event)
{
    if (event->button() == Qt::LeftButton && isCapturing) {
        isCapturing = false;
        
        // 确保矩形有效
        if (captureRect.width() > 10 && captureRect.height() > 10) {
            // 调整矩形为正方向
            QRect normalizedRect = captureRect.normalized();
            
            // 确保矩形在屏幕范围内
            normalizedRect = normalizedRect.intersected(rect());
            
            // 核心修正：利用逻辑坐标直接裁切
            // 如果 fullScreen 已经设置了正确的 DevicePixelRatio，
            // 我们可以通过这种方式获取"物理像素级"的矩形：
            qreal dpr = fullScreen.devicePixelRatio();
            QRect realRect(
                normalizedRect.x() * dpr,
                normalizedRect.y() * dpr,
                normalizedRect.width() * dpr,
                normalizedRect.height() * dpr
            );
            
            // 添加调试信息
            qDebug() << "原始捕获矩形:" << captureRect;
            qDebug() << "规范化后矩形:" << normalizedRect;
            qDebug() << "物理像素矩形:" << realRect;
            qDebug() << "窗口矩形:" << rect();
            qDebug() << "截图尺寸:" << fullScreen.size();
            qDebug() << "截图设备像素比例:" << dpr;
            
            // 截取选定区域 - 从全屏截图中复制对应区域
            // 确保矩形在截图范围内
            QRect screenshotRect(0, 0, fullScreen.width() * dpr, fullScreen.height() * dpr);
            realRect = realRect.intersected(screenshotRect);
            QPixmap screenshot = fullScreen.copy(realRect);
            
            // 发送完成信号
            emit captureCompleted(screenshot);
        }
        
        // 关闭窗口
        close();
    }
}

void ScreenCapture::paintEvent(QPaintEvent *event)
{
    Q_UNUSED(event);
    
    QPainter painter(this);
    painter.setRenderHint(QPainter::Antialiasing);
    
    // 绘制全屏截图 - 作为底层图像
    painter.drawPixmap(0, 0, fullScreen);
    
    // 绘制半透明蒙层 - 覆盖整个屏幕
    painter.setBrush(QColor(0, 0, 0, 100));
    painter.drawRect(rect());
    
    // 绘制右上角关闭按钮
    painter.setRenderHint(QPainter::Antialiasing);
    
    // 按钮背景
    if (isCloseButtonHovered) {
        painter.setBrush(QColor(255, 100, 100));
    } else {
        painter.setBrush(QColor(255, 255, 255, 200));
    }
    painter.setPen(QColor(200, 200, 200));
    painter.drawRoundedRect(closeButtonRect, 20, 20);
    
    // 按钮文字 ×
    painter.setPen(QColor(51, 51, 51));
    QFont font = painter.font();
    font.setPointSize(18);
    font.setBold(true);
    painter.setFont(font);
    painter.drawText(closeButtonRect, Qt::AlignCenter, "×");
    
    // 绘制说明标签
    QRect labelRect(width() - 200, 60, 180, 30);
    painter.setBrush(QColor(0, 0, 0, 150));
    painter.setPen(Qt::NoPen);
    painter.drawRoundedRect(labelRect, 4, 4);
    
    painter.setPen(Qt::white);
    font.setPointSize(12);
    font.setBold(false);
    painter.setFont(font);
    painter.drawText(labelRect, Qt::AlignCenter, "按ESC或点击×取消");
    
    // 绘制选中区域
    if (isCapturing) {
        QRect rect = captureRect.normalized();
        
        // 绘制选中区域的边框
        painter.setPen(QPen(QColor(90, 138, 90), 2));
        painter.setBrush(QBrush(QColor(90, 138, 90, 50)));
        painter.drawRect(rect);
        
        // 绘制选中区域的文字提示
        painter.setPen(Qt::white);
        painter.drawText(rect.topLeft() - QPoint(0, 20), "拖动鼠标选择截图区域");
    } else {
        // 绘制提示文字
        painter.setPen(Qt::white);
        painter.drawText(rect(), Qt::AlignCenter, "按鼠标左键拖动选择截图区域，按ESC或点击×取消");
    }
}

void ScreenCapture::keyPressEvent(QKeyEvent *event)
{
    if (event->key() == Qt::Key_Escape) {
        // 发送取消信号
        emit captureCanceled();
        
        // 关闭窗口
        close();
    }
}