// Simple HTTP server that tells the time.

#include "caf/actor_system.hpp"
#include "caf/actor_system_config.hpp"
#include "caf/caf_main.hpp"
#include "caf/deep_to_string.hpp"
#include "caf/event_based_actor.hpp"
#include "caf/net/http/serve.hpp"
#include "caf/net/middleman.hpp"
#include "caf/net/stream_transport.hpp"
#include "caf/net/tcp_accept_socket.hpp"
#include "caf/net/tcp_stream_socket.hpp"
#include "caf/scheduled_actor/flow.hpp"

#include <iostream>
#include <utility>

static constexpr uint16_t default_port = 8080;

struct config : caf::actor_system_config {
  config() {
    opt_group{custom_options_, "global"} //
      .add<uint16_t>("port,p", "port to listen for incoming connections");
  }
};

int caf_main(caf::actor_system& sys, const config& cfg) {
  using namespace caf;
  // Open up a TCP port for incoming connections.
  auto port = caf::get_or(cfg, "port", default_port);
  net::tcp_accept_socket fd;
  if (auto maybe_fd = net::make_tcp_accept_socket({ipv4_address{}, port},
                                                  true)) {
    std::cout << "*** started listening for incoming connections on port "
              << port << '\n';
    fd = std::move(*maybe_fd);
  } else {
    std::cerr << "*** unable to open port " << port << ": "
              << to_string(maybe_fd.error()) << '\n';
    return EXIT_FAILURE;
  }
  // Create buffers to signal events from the WebSocket server to the worker.
  auto [worker_pull, server_push] = net::http::make_request_resource();
  // Spin up the HTTP server.
  net::http::serve(sys, fd, std::move(server_push));
  // Spin up a worker to handle the HTTP requests.
  auto worker = sys.spawn([wres = worker_pull](event_based_actor* self) {
    // For each incoming request ...
    wres
      .observe_on(self) //
      .for_each([](const net::http::request& req) {
        // ... we simply return the current time as string.
        // Note: we cannot respond more than once to a request.
        auto str = caf::deep_to_string(make_timestamp());
        req.respond(net::http::status::ok, "text/plain", str);
      });
  });
  sys.await_all_actors_done();
  return EXIT_SUCCESS;
}

CAF_MAIN(caf::net::middleman)
