#include "camera_streamer.h"

#include <QDebug>
#include <QHostAddress>
#include <opencv2/imgproc.hpp>
#include <opencv2/imgcodecs.hpp>

CameraStreamer::CameraStreamer(QObject *parent)
    : QObject(parent)
{
}

CameraStreamer::~CameraStreamer()
{
    stopStreaming();
}

bool CameraStreamer::startStreaming(const QString &remoteUser,
                                    const QString &remoteHost,
                                    const QString &remoteCommand,
                                    int localPort)
{
    if (m_running.load())
        return true; // already running

    // 启动 ssh 进程，在远端开始推流
    if (!m_sshProcess) {
        m_sshProcess = new QProcess(this);
        // 使 ssh 保持会话 & 不读取stdin，-T 禁用伪终端
        QStringList args;
        args << QString("%1@%2").arg(remoteUser, remoteHost)
             << "-T" << remoteCommand;
        m_sshProcess->start("ssh", args);
        if (!m_sshProcess->waitForStarted(3000)) {
            qWarning() << "Failed to start ssh process:" << m_sshProcess->errorString();
            delete m_sshProcess;
            m_sshProcess = nullptr;
            return false;
        }
    }

    // 启动本地接收线程
    m_running = true;
    m_captureThread = std::thread(&CameraStreamer::captureLoop, this, localPort);
    return true;
}

void CameraStreamer::stopStreaming()
{
    if (!m_running.load())
        return;

    // 停止读取线程
    m_running = false;
    if (m_captureThread.joinable())
        m_captureThread.join();

    // 结束远端 ssh 进程
    if (m_sshProcess) {
        m_sshProcess->terminate();
        if (!m_sshProcess->waitForFinished(3000)) {
            m_sshProcess->kill();
            m_sshProcess->waitForFinished();
        }
        delete m_sshProcess;
        m_sshProcess = nullptr;
    }
}

void CameraStreamer::captureLoop(int localPort)
{
    // GStreamer UDP pipeline
    QString pipeline = QString("udpsrc address=0.0.0.0 port=%1 ! application/x-rtp,media=video,encoding-name=H264 ! rtph264depay ! h264parse ! avdec_h264 ! videoconvert ! appsink max-buffers=1 drop=true").arg(localPort);

    cv::VideoCapture cap(pipeline.toStdString(), cv::CAP_GSTREAMER);
    if (!cap.isOpened()) {
        qWarning() << "Failed to open capture pipeline" << pipeline;
        return;
    }

    cv::Mat frame;
    while (m_running.load()) {
        if (!cap.read(frame) || frame.empty()) {
            std::this_thread::sleep_for(std::chrono::milliseconds(10));
            continue;
        }

        cv::Mat rgb;
        if (frame.channels() == 3) {
            cv::cvtColor(frame, rgb, cv::COLOR_BGR2RGB);
        } else if (frame.channels() == 4) {
            cv::cvtColor(frame, rgb, cv::COLOR_BGRA2RGB);
        } else {
            rgb = frame;
        }

        QImage image(rgb.data, rgb.cols, rgb.rows, static_cast<int>(rgb.step), QImage::Format_RGB888);
        emit newFrame(image.copy()); // copy to detach from cv::Mat memory

        // 控制帧率：根据需要调整
        std::this_thread::sleep_for(std::chrono::milliseconds(1));
    }

    cap.release();
}