#include <iostream>
#include <sys/socket.h>
#include <stdlib.h>
#include <netinet/in.h>
#include <string.h>
#include <arpa/inet.h>
#include <unistd.h>
#include <errno.h>
#include <functional>
#include <fstream>
#include <chrono>
#include <thread>
#include <ctime>
#include <iomanip>
#include <csignal>
#include <loguru.hpp>

const char * HOST = "192.168.30.89";
const uint32_t PORT = 9999;
const size_t MAX_EVENT_SIZE = 33484; // in bytes
const size_t MIN_EVENT_SIZE = 204; // in bytes
const bool verbose = true;

int sock = 0;
bool running = true;
int open_socket();
void signalHandler( int signum );

bool bad_data = true;

int main(int argc, char const* argv[])
{
   signal(SIGINT, signalHandler);
   int ret = open_socket();
   if (ret != 0)
      return -1;

   char char_buffer[MAX_EVENT_SIZE];
   uint32_t * wordData = (uint32_t*) char_buffer;
   ssize_t nread;

   fd_set select_fds;                // fd's used by select
   struct timeval timeout;           // Time value for time out
   //Timeout set for 0 sec + 200 millisec
   timeout.tv_sec = 0;         
   timeout.tv_usec = 200*1000;
   std::chrono::duration<int, std::milli> polling_period(2);

   while (running) {
      // Setup the descriptor set for select()
      FD_ZERO(&select_fds);            
      FD_SET(sock, &select_fds);           
      if ( select(sock + 1, &select_fds, NULL, NULL, &timeout) == 0 ){
         std::this_thread::sleep_for(polling_period);
      }
      else{
         // read in first 4 bytes
         nread = recv(sock, char_buffer, 4, 0);
         LOG_IF_F(INFO, verbose, "read in %u bytes: 0x%08X", nread, wordData[0]);
         // if not A5 marker, go to next iteration (read in 4 more bytes)
         if ((char_buffer[0] & 0xFF) != 0xA5){
            bad_data = true;
            continue;
         }
         else {
            bad_data = false;
            size_t frameSize = 4 * (wordData[0] >> 8);
            nread = recv(sock, char_buffer, frameSize - 4, 0);
            // nread + 4 must be between MIN_EVENT_SIZE and MAX_EVENT_SIZE, and equal to frameSize.
            if ((nread != frameSize - 4) || (frameSize < MIN_EVENT_SIZE)|| (frameSize > MAX_EVENT_SIZE)){
               bad_data = true;
               continue;
            }
            else {
               // ok, this seems to be good data
               LOG_IF_F(INFO, verbose, "next %u bytes (expecting %u): 0x%08X",
                     nread, frameSize - 4, wordData[0]);
               uint8_t board_id = (wordData[0] >> 24) & 0xFF;
               uint8_t version = wordData[0] & 0xFF;
               uint16_t spill_id = (wordData[1] & 0x00FFFF00) >> 8;
               uint8_t channel_count = (wordData[1]) & 0x000000FF;
               LOG_IF_F(INFO, verbose, "board %u, version %u, spill %u, channel_count %u",
                     static_cast<uint32_t>(board_id),
                     static_cast<uint32_t>(version),
                     static_cast<uint32_t>(spill_id),
                     static_cast<uint32_t>(channel_count));

               if ((board_id > 4) || (board_id < 1) || (version != 1) || (channel_count > 8) || (channel_count < 1)) {
                  bad_data = true;
                  continue;
               }
               else {

               }

            }
         }
      }
   }

   close(sock);
   return 0;
}

void signalHandler( int signum ) {
   LOG_F(WARNING, "Interrupt signal (%d) received, exiting...", signum);
   running = false;
}

int open_socket(){
   struct sockaddr_in serv_addr;
   if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0) {
      std::cerr << "Cannot create socket" << std::endl;
      return -1;
   }

   memset(&serv_addr, '0', sizeof(serv_addr));
   serv_addr.sin_family = AF_INET;
   serv_addr.sin_port = htons(PORT);

   if(inet_pton(AF_INET, HOST, &serv_addr.sin_addr)<=0) {
      std::cerr << "Invalid address or Address not supported" << std::endl;
      return -1;
   }

   if (connect(sock, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0) {
      std::cerr << "Cannot connect to " << HOST << ":" << PORT << std::endl;
      return -1;
   }

   return 0;
}