#pragma once

#include <asio.hpp>
#include <cstdint>
#include <functional>
#include <memory>
#include <string>

#include "secsgem/hsms/connection.hpp"
#include "secsgem/hsms/header.hpp"

namespace secsgem {

using hsms::Connection;
using hsms::Timers;

// Passive (equipment) endpoint: listens for inbound TCP connections and turns
// each into a passive HSMS Connection. The connection handler is invoked once
// per accepted session so the application can install message/selected handlers
// before the session starts.
class Server {
 public:
  struct Config {
    uint16_t port = 5000;
    uint16_t device_id = 0;
    Timers timers{};
  };

  using ConnectionHandler = std::function<void(std::shared_ptr<Connection>)>;
  using LogHandler = std::function<void(const std::string&)>;

  Server(asio::io_context& io, Config cfg);

  void on_connection(ConnectionHandler h) { on_connection_ = std::move(h); }
  void on_log(LogHandler h) { on_log_ = std::move(h); }

  void start();

 private:
  void do_accept();
  void log(const std::string& msg);

  asio::io_context& io_;
  asio::ip::tcp::acceptor acceptor_;
  Config cfg_;
  ConnectionHandler on_connection_;
  LogHandler on_log_;
};

// Active (host) endpoint: connects out to a passive peer, retrying every T5 on
// failure, and turns the socket into an active HSMS Connection (which initiates
// SELECT). The connection handler is invoked once the TCP connection is up.
class Client {
 public:
  struct Config {
    std::string host = "127.0.0.1";
    uint16_t port = 5000;
    uint16_t device_id = 0;
    Timers timers{};
  };

  using ConnectionHandler = std::function<void(std::shared_ptr<Connection>)>;
  using LogHandler = std::function<void(const std::string&)>;

  Client(asio::io_context& io, Config cfg);

  void on_connection(ConnectionHandler h) { on_connection_ = std::move(h); }
  void on_log(LogHandler h) { on_log_ = std::move(h); }

  void start();

 private:
  void do_connect();
  void schedule_retry();
  void log(const std::string& msg);

  asio::io_context& io_;
  asio::ip::tcp::resolver resolver_;
  asio::steady_timer retry_timer_;
  Config cfg_;
  ConnectionHandler on_connection_;
  LogHandler on_log_;
};

}  // namespace secsgem