/*
本程序用于视频分流
1.推流摄像头画面至RTSP服务器,交由YOLO模型进行处理
2.接收YOLO传来的坐标,深度,警报等级等等数据
3.根据获取到的数据绘制边框和相应数据
4.将绘制完毕的视频流继续推流至RTSP服务器用于输出
*/

#include <iostream>
#include <opencv4/opencv2/opencv.hpp>
#include <mqtt/async_client.h>
#include <nlohmann/json.hpp>

using namespace std;
using namespace cv;
using namespace chrono_literals;

// 全局变量
VideoCapture cap(0);
Mat handleFrame;
const string mqtt_url = "tcp://192.168.12.1:1883";
const string clientId = "video_subData";
const string Topic = "/video/Data";
const int Qos = 1;
mqtt::async_client client(mqtt_url, clientId);

// 函数声明
// mqtt初始化
void MqttInit();
// 摄像头管道初始化
bool videoInit(VideoCapture &cap);
// ffmpeg管道初始化
FILE *pipeInit();
// 对单个帧进行处理
bool processFrame(VideoCapture &cap, FILE *pipe, Mat &frame, int64 &count, chrono::steady_clock::time_point &t0);
// 资源清理
void cleanup(FILE *pipe, VideoCapture &cap);
// 主循环
void mainLoop(VideoCapture &cap, FILE *pipe);
// mqtt接收订阅消息的回调
void getMsgCallback(mqtt::const_message_ptr msg);
// 绘制矩形方框和深度信息
void drawRect(int x, int y, int w, int h, double distance);

int main()
{
    // 初始化摄像头
    if (!videoInit(cap))
    {
        return -1;
    }

    // 初始化FFmpeg管道
    FILE *pipe = pipeInit();
    if (!pipe)
    {
        return -1;
    }

    // 主处理循环
    mainLoop(cap, pipe);

    // 清理资源
    cleanup(pipe, cap);

    return 0;
}

// 绘制矩形方框和深度信息
void drawRect(int x, int y, int w, int h, double distance)
{
    Rect r(x, y, w, h);
    rectangle(handleFrame, r, Scalar(0, 255, 0), 2);
}

// mqtt初始化
void MqttInit()
{
    // 设置回调
    client.set_connected_handler([](const string &cause)
                                 { cout << "连接成功" << endl; });

    client.set_message_callback(getMsgCallback);

    client.connect()->wait();
    client.subscribe(Topic, Qos)->wait();
}

// mqtt接收订阅消息的回调
void getMsgCallback(mqtt::const_message_ptr msg)
{
    string payload = msg->to_string();

    cout << payload << endl;
}

// 摄像头初始化
bool videoInit(VideoCapture &cap)
{
    if (!cap.isOpened())
    {
        cerr << "摄像头打开失败,请重试" << endl;
        return false;
    }

    //  降低分辨率,固定MJPG编码
    cap.set(CAP_PROP_FOURCC, VideoWriter::fourcc('M', 'J', 'P', 'G'));
    cap.set(CAP_PROP_FRAME_WIDTH, 640);
    cap.set(CAP_PROP_FRAME_HEIGHT, 480);
    cap.set(CAP_PROP_FPS, 30);
    cap.set(CAP_PROP_BUFFERSIZE, 1);

    cout << "摄像头初始化成功" << endl;
    return true;
}

// FFmpeg管道初始化
FILE *pipeInit()
{
    FILE *pipe = popen(
        "ffmpeg "
        "-f rawvideo -pixel_format bgr24 -video_size 640x480 -framerate 30 "
        "-i - "
        "-c:v h264_rkmpp "
        "-rc_mode 2 -qp_init 32 "
        "-profile baseline -coder cavlc "
        "-g 1 -bf 0 "
        "-fflags nobuffer -flags low_delay "
        "-f h264 udp://192.168.12.1:8888?pkt_size=1316",
        "w");

    if (!pipe)
    {
        cerr << "FFmpeg管道打开失败" << endl;
        return nullptr;
    }

    // 设置无缓冲模式
    setvbuf(pipe, NULL, _IONBF, 0);
    cout << "FFmpeg管道初始化成功" << endl;

    return pipe;
}

// 处理单帧
bool processFrame(VideoCapture &cap, FILE *pipe, Mat &frame, int64 &count, chrono::steady_clock::time_point &t0)
{
    // 读取帧
    cap.read(frame);
    if (frame.empty())
    {
        cerr << "读取帧失败" << endl;
        return false;
    }

    // 拷贝视频帧
    handleFrame = frame;

    // 添加提示文本
    putText(frame, "press 'q' to quit", Point(0, 20),
            FONT_HERSHEY_SIMPLEX, 1.0, Scalar(0, 255, 0), 2, LINE_8);

    // FPS计算与显示
    ++count;
    auto now = chrono::steady_clock::now();
    if (chrono::duration_cast<chrono::milliseconds>(now - t0).count() / 1000.0 > 1.0)
    {
        string fps = "FPS:" + to_string(count);
        count = 0;
        t0 = now;
    }

    // 写入管道
    fwrite(frame.data, 1, frame.total() * frame.elemSize(), pipe);
    fflush(pipe);

    // 可选：显示窗口
    // imshow("测试画面", frame);

    return true;
}

// 主处理循环
void mainLoop(VideoCapture &cap, FILE *pipe)
{
    int64 count = 0;
    auto t0 = chrono::steady_clock::now();
    Mat frame;
    cout << "开始视频处理循环..." << endl;

    // 创建全屏窗口
    namedWindow("处理后的画面", WINDOW_NORMAL);
    setWindowProperty("处理后的画面", WND_PROP_FULLSCREEN, WINDOW_FULLSCREEN);
    
    // 获取屏幕尺寸（通过获取全屏窗口的实际大小）
    cv::Rect windowRect = getWindowImageRect("处理后的画面");
    int screenWidth = windowRect.width > 0 ? windowRect.width : 1920;
    int screenHeight = windowRect.height > 0 ? windowRect.height : 1080;
    
    Mat displayFrame;  // 用于存储缩放后的画面

    while (true)
    {
        if (!processFrame(cap, pipe, frame, count, t0))
        {
            break;
        }
        
        // 将 handleFrame 缩放到全屏尺寸
        resize(handleFrame, displayFrame, Size(screenWidth, screenHeight));
        imshow("处理后的画面", displayFrame);
        // 检测退出键
        if (cv::waitKey(1) == 'q')
        {
            cout << "用户请求退出" << endl;
            break;
        }
    }
}

// 资源清理
void cleanup(FILE *pipe, VideoCapture &cap)
{
    if (pipe)
    {
        pclose(pipe);
        cout << "FFmpeg管道已关闭" << endl;
    }

    if (cap.isOpened())
    {
        cap.release();
        cout << "摄像头已释放" << endl;
    }

    destroyAllWindows();
    cout << "所有资源已清理完毕" << endl;
}