//=============================================================================
// fc2view — minimal live viewer for Point Grey / FLIR FlyCapture2 cameras.
//
// The vendor GUI (FlyCap2) can't run on Ubuntu 24.04 (dead GTK2 deps), so
// this is a small native replacement built on OpenCV. It connects to the
// first camera on the bus, streams frames into a window, and lets you save
// snapshots.
//
//   Keys:  q or Esc  quit
//          s          save a snapshot (PNG, native bit depth) to $PWD
//
// Build:  g++ fc2view.cpp -I/usr/include/flycapture \
//             $(pkg-config --cflags --libs opencv4) -lflycapture -o fc2view
//=============================================================================

#include "FlyCapture2.h"
#include <opencv2/opencv.hpp>

#include <ctime>
#include <iomanip>
#include <iostream>
#include <sstream>

using namespace FlyCapture2;

static void printError(const Error &e) { e.PrintErrorTrace(); }

// Timestamped filename like fc2-<serial>-20260929-142530.png
static std::string snapshotName(unsigned int serial)
{
    std::time_t t = std::time(nullptr);
    std::tm tm = *std::localtime(&t);
    std::ostringstream s;
    s << "fc2-" << serial << "-"
      << std::put_time(&tm, "%Y%m%d-%H%M%S") << ".png";
    return s.str();
}

int main()
{
    BusManager busMgr;
    unsigned int numCameras = 0;
    Error error = busMgr.GetNumOfCameras(&numCameras);
    if (error != PGRERROR_OK) { printError(error); return 1; }
    if (numCameras == 0)
    {
        std::cerr << "No FlyCapture2 cameras detected. Check `lsusb` for "
                     "1e10:xxxx and your 'flirimaging' group membership.\n";
        return 1;
    }

    PGRGuid guid;
    error = busMgr.GetCameraFromIndex(0, &guid);
    if (error != PGRERROR_OK) { printError(error); return 1; }

    Camera cam;
    error = cam.Connect(&guid);
    if (error != PGRERROR_OK) { printError(error); return 1; }

    CameraInfo camInfo;
    if (cam.GetCameraInfo(&camInfo) == PGRERROR_OK)
    {
        std::cout << "Connected: " << camInfo.modelName
                  << "  serial " << camInfo.serialNumber
                  << "  (" << camInfo.sensorResolution << ")\n";
    }

    error = cam.StartCapture();
    if (error != PGRERROR_OK) { printError(error); cam.Disconnect(); return 1; }

    const std::string win = "fc2view";
    cv::namedWindow(win, cv::WINDOW_NORMAL);
    std::cout << "Streaming. Keys: 'q'/Esc quit, 's' save snapshot.\n";

    Image rawImage, bgrImage;
    while (true)
    {
        error = cam.RetrieveBuffer(&rawImage);
        if (error != PGRERROR_OK) { printError(error); continue; }

        // Convert whatever the sensor delivers (mono, Bayer, ...) to 8-bit BGR
        // so it maps straight onto an OpenCV CV_8UC3 Mat with no reordering.
        error = rawImage.Convert(PIXEL_FORMAT_BGR, &bgrImage);
        if (error != PGRERROR_OK) { printError(error); continue; }

        cv::Mat frame(bgrImage.GetRows(), bgrImage.GetCols(), CV_8UC3,
                      bgrImage.GetData(), bgrImage.GetStride());
        if (frame.empty()) continue;

        cv::imshow(win, frame);

        int key = cv::waitKey(1) & 0xFF;
        if (key == 'q' || key == 27) break;          // q or Esc
        if (key == 's')
        {
            // Save the raw frame so native bit depth (e.g. Mono16 on a SWIR
            // sensor) is preserved, not the 8-bit display copy.
            std::string name = snapshotName(camInfo.serialNumber);
            PNGOption png;
            if (rawImage.Save(name.c_str(), &png) == PGRERROR_OK)
                std::cout << "Saved " << name << "\n";
            else
                std::cerr << "Failed to save " << name << "\n";
        }
    }

    cam.StopCapture();
    cam.Disconnect();
    cv::destroyAllWindows();
    return 0;
}