#include <fmt/core.h>
#include <nlohmann/json.hpp>
#include <fstream>
#include "dbc.hpp"

#define BUF_MAX 1024 * 10
using namespace fmt;
using namespace nlohmann;

FILE *run_ffmpeg(const string listen_at, const string bitrate, const string send_to) {
  string ffmpeg_cmd = format("ffmpeg -listen 1 -i {} -bufsize 3000k  -maxrate {} -flags +global_header  -c:v libx264  -preset veryfast -tune zerolatency  -g:v 60  -vb {} -c:a copy -f flv {}",
      listen_at, bitrate, bitrate, send_to);

  println("RUNNING: {}", ffmpeg_cmd);

  FILE *handle = popen(ffmpeg_cmd.c_str(), "r");
  dbc::check(handle != nullptr, "failed to start ffmpeg");
  return handle;
}

json load_config(const string file_name) {
  std::ifstream infile(file_name);
  return json::parse(infile);
}

int main() {
  FILE *handle = nullptr;
  char buffer[BUF_MAX];
  char *res = nullptr;
  json config = load_config("config.json");

  const string listen_at = config["listen_at"].template get<string>();
  const string bitrate = config["bitrate"].template get<string>();
  const string send_to = config["send_to"].template get<string>();

  handle = run_ffmpeg(listen_at, bitrate, send_to);

  do {
    res = fgets(buffer, BUF_MAX, handle);
    print("OUT: {}", res);
  } while(res != nullptr);

  int rc = pclose(handle);
  dbc::check(rc == 0, "error closing ffmpeg");
}