open Types

let create_udp_socket (net : _ Eio.Net.t) ~sw ~addr ~port :
    _ Eio.Net.datagram_socket_ty Eio.Resource.t =
  let bind_addr =
    match Eio.Net.Ipaddr.of_raw addr with ip -> `Udp (ip, port)
  in
  Eio.Net.datagram_socket ~sw net bind_addr

let send_udp sock dst buf = Eio.Net.send sock ~dst [ buf ]

let recv_udp sock buf =
  let dst, n = Eio.Net.recv sock buf in
  (n, dst)

let create_tcp_listener (net : _ Eio.Net.t) ~sw ~addr ~port ~backlog =
  let bind_addr =
    match Eio.Net.Ipaddr.of_raw addr with ip -> `Tcp (ip, port)
  in
  Eio.Net.listen ~sw ~backlog net bind_addr

let connect_tcp (net : _ Eio.Net.t) ~sw ~addr ~timeout ~clock =
  try
    Ok
      (Eio.Time.with_timeout_exn clock timeout (fun () ->
           Eio.Net.connect ~sw net addr))
  with
  | Eio.Time.Timeout -> Error Timeout
  | Eio.Io (Eio.Net.E (Connection_failure _), _) -> Error Node_unreachable
  | Eio.Io (Eio.Net.E (Connection_reset _), _) -> Error Connection_reset

let send_tcp sock buf =
  try
    Eio.Flow.write sock [ buf ];
    Ok ()
  with
  | Eio.Io (Eio.Net.E (Connection_reset _), _) -> Error Connection_reset
  | End_of_file -> Error Connection_reset

let recv_tcp sock buf =
  try
    let n = Eio.Flow.single_read sock buf in
    Ok n
  with
  | Eio.Io (Eio.Net.E (Connection_reset _), _) -> Error Connection_reset
  | End_of_file -> Error Connection_reset

let parse_addr_port s =
  match String.rindex_opt s ':' with
  | None -> Error `Invalid_addr
  | Some idx -> (
      let host = String.sub s 0 idx in
      let port_str = String.sub s (idx + 1) (String.length s - idx - 1) in
      match int_of_string_opt port_str with
      | None -> Error `Invalid_addr
      | Some port ->
          if port < 0 || port > 65535 then Error `Invalid_addr
          else Ok (host, port))

let parse_udp_addr s =
  match parse_addr_port s with
  | Error e -> Error e
  | Ok (host, port) -> (
      try
        let ip = Eio.Net.Ipaddr.of_raw host in
        Ok (`Udp (ip, port))
      with _ -> Error `Invalid_addr)

let parse_tcp_addr s =
  match parse_addr_port s with
  | Error e -> Error e
  | Ok (host, port) -> (
      try
        let ip = Eio.Net.Ipaddr.of_raw host in
        Ok (`Tcp (ip, port))
      with _ -> Error `Invalid_addr)