#include <cstring>
#include <fcntl.h>
#include <filesystem>
#include <fstream>
#include <iostream>
#include <ostream>
#include <pthread.h>
#include <string>
#include <unistd.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <netinet/in.h>

#include <logger.hpp>
#ifdef __SWITCH__
#include <switch.h>
#include <client.hpp>
namespace fs = std::filesystem;
#else
namespace fs = std::__fs::filesystem;
#endif
#define PORT 8080
#define BUFFER_SIZE 1024
#define MULTICAST_PORT 8081
#define MULTICAST_GROUP "239.0.0.1" // Multicast group IP

struct ThreadArgs
{
  char **filenames;
  int file_count;
  int sock;
  fs::path directory;
};

bool receiveAck(int sock)
{
  char ack[4] = {0};
  int bytes_received = read(sock, ack, 3);
  return bytes_received > 0 && std::string(ack) == "ACK";
}

// Отправка строки с учетом её длины
void send_string(int sock, const std::string &str)
{
  size_t length = str.size();
  send(sock, &length, sizeof(length), 0);
  send(sock, str.c_str(), length, 0);
}

void *send_files_thread(void *args)
{
  ThreadArgs *thread_args = static_cast<ThreadArgs *>(args);
  char **filenames = thread_args->filenames;
  int file_count = thread_args->file_count;
  int sock = thread_args->sock;
  fs::path cwd = thread_args->directory;
  delete thread_args;

  char buffer[BUFFER_SIZE];

  // Send the directory length

  std::cout << Logger::INFO << "cwd.filename is: " << cwd.filename().c_str() << std::endl; // Get the parent directory
  std::string dirname = cwd.parent_path().filename();
  uint32_t directory_len = dirname.size();
  send(sock, &directory_len, sizeof(directory_len), 0);

  // Send the dirname
  send(sock, dirname.c_str(), directory_len, 0);

  for (int i = 0; i < file_count; ++i)
  {
    std::string path = filenames[i];  
    std::size_t found = path.find_last_of("/\\");
    std::string filename = path.substr(found+1);
    std::ifstream infile(path, std::ios::binary | std::ios::ate);
    if (!infile.is_open())
    {
      std::cout << Logger::ERROR << "File not found: " << filename.c_str() << std::endl;
      return nullptr;
    }

    // Get the size of the file
    std::streamsize file_size = infile.tellg();
    infile.seekg(0, std::ios::beg);

    // Send the filename length
    uint32_t filename_len = filename.size();
    std::cout << Logger::INFO << "Send filename length: " << filename_len << std::endl;
    send(sock, &filename_len, sizeof(filename_len), 0);

    // Send the filename
    std::cout << Logger::INFO << "Send file name: " << filename.c_str() << std::endl;
    send(sock, filename.c_str(), filename_len, 0);

    // Send the file size
    std::cout << Logger::INFO << "Send file size: " << file_size << std::endl;
    send(sock, &file_size, sizeof(file_size), 0);

    char buffer[BUFFER_SIZE];
    // Send the file data
    while (file_size > 0)
    {
      infile.read(buffer, BUFFER_SIZE);
      send(sock, buffer, infile.gcount(), 0);
      file_size -= infile.gcount();
      std::cout << Logger::INFO << "wait for ACK" << std::endl;
      // Wait for acknowledgment after each chunk
      if (!receiveAck(sock))
      {
        std::cout << Logger::ERROR << "Failed to receive acknowledgment" << std::endl;;
      }
    }

    send(sock, 0, 0, 0);

    std::cout << Logger::INFO << "File sent successfully: " << filename.c_str() << std::endl;

    infile.close();
  }

  close(sock);
  pthread_exit(nullptr);
}

int find_server(char *server_ip)
{
  std::cout << Logger::INFO << "Init find_server" << std::endl;;
  int sockfd;
  struct sockaddr_in multicast_addr;

  std::cout << Logger::INFO << "Create socket" << std::endl;

  if ((sockfd = socket(AF_INET, SOCK_DGRAM, 0)) < 0)
  {
    std::cout << Logger::ERROR << "Socket creation error" << std::endl;
    return -1;
  }

  memset(&multicast_addr, 0, sizeof(multicast_addr));

  multicast_addr.sin_family = AF_INET;
  multicast_addr.sin_port = htons(MULTICAST_PORT);
  multicast_addr.sin_addr.s_addr = inet_addr(MULTICAST_GROUP);

  std::cout << Logger::INFO << "Send DISCOVER_SERVER" << std::endl;

  const char *multicast_message = "DISCOVER_SERVER";
  if (sendto(sockfd, multicast_message, strlen(multicast_message), 0, (struct sockaddr *)&multicast_addr, sizeof(multicast_addr)) < 0)
  {
    std::cout << Logger::ERROR << "sendto failed" << std::endl;
    close(sockfd);
    return -1;
  }
  else
  {
    std::cout << Logger::INFO << "send multicast message success" << std::endl;
  }

  struct sockaddr_in cliaddr;
  socklen_t len = sizeof(cliaddr);
  char buffer[BUFFER_SIZE];

  ssize_t n = recvfrom(sockfd, buffer, BUFFER_SIZE, 0, (struct sockaddr *)&cliaddr, &len);
  std::cout << Logger::INFO << "recvfrom n: %i" << n << std::endl;
  if (n < 0)
  {
    std::cout << Logger::ERROR << "recvfrom failed" << std::endl;
    close(sockfd);
    return -1;
  }
  std::cout << Logger::INFO << "buffer: " << buffer << std::endl;
  buffer[n] = '\0';
  if (strcmp(buffer, "SERVER_HERE") == 0)
  {
    std::cout << Logger::INFO << "Server found"  << std::endl;
    inet_ntop(AF_INET, &cliaddr.sin_addr, server_ip, INET_ADDRSTRLEN);
  }
  else
  {
    std::cout << Logger::ERROR << "Unable to find server, close socket" << std::endl;;
    close(sockfd);
    return -1;
  }

  close(sockfd);
  return 0;
}

int transfer_files(fs::path directory, char **filenames, int file_count) {
  std::cout << Logger::INFO << "Init transfer_files" << std::endl;
  char server_ip[INET_ADDRSTRLEN];
  if (find_server(server_ip) != 0)
  {
    std::cout << Logger::ERROR << "Failed to find server" << std::endl;
    return -1;
  }

  int sock = 0;
  struct sockaddr_in serv_addr;

  if ((sock = socket(AF_INET, SOCK_STREAM, 0)) < 0)
  {
    std::cout << Logger::ERROR << "Socket creation error" << std::endl;
    return -1;
  }

  serv_addr.sin_family = AF_INET;
  serv_addr.sin_port = htons(PORT);

  if (inet_pton(AF_INET, server_ip, &serv_addr.sin_addr) <= 0)
  {
    std::cout << Logger::ERROR << "Invalid address / Address not supported" << std::endl;
    return -1;
  }

  if (connect(sock, (struct sockaddr *)&serv_addr, sizeof(serv_addr)) < 0)
  {
    std::cout << Logger::ERROR << "Connection failed" << std::endl;
    return -1;
  }

  pthread_t file_thread;
  ThreadArgs *thread_args = new ThreadArgs{filenames, file_count, sock, directory};
  if (pthread_create(&file_thread, nullptr, send_files_thread,
                     (void *)thread_args) < 0)
  {
    std::cout << Logger::ERROR << "Thread creation failed" << std::endl;
    close(sock);
    delete thread_args;
    return -1;
  }
  else
  {
    std::cout << Logger::INFO << "Wait for file_thread" << std::endl;
    pthread_join(file_thread, nullptr);
  }
  return 0;
}

#ifndef __SWITCH__ // for desktop
int main(int argc, char *argv[])
{
  if (argc < 2)
  {
    std::cerr << "Usage: " << argv[0] << " <filename1> <filename2> ..." << std::endl;
    return 1;
  }

  char **filenames = const_cast<char **>(&argv[1]);
  int file_count = argc - 1;

  transfer_files(filenames, file_count);

  return 0;
}
#endif