open Bos.OS
open Syntax
open Crypto

let read fname =
  let* b = File.exists fname |> Syntax.unwrap_err_msg in
  match b with
  | false -> Ok None
  | true ->
      let+ content = File.read fname |> Syntax.unwrap_err_msg in
      Some content

let write_eddsa fname priv =
  EddsaPrivateKey.to_octets priv |> File.write fname |> Syntax.unwrap_err_msg

let write_rsa fname priv =
  RsaPrivateKey.to_octets priv |> File.write fname |> Syntax.unwrap_err_msg

let read_eddsa fname =
  let* opt = read fname in
  match opt with
  | None -> Ok None
  | Some data -> (
      EddsaPrivateKey.of_octets data |> function
      | Error e -> Error e
      | Ok v -> Ok (Some v))

let read_rsa fname =
  let* opt = read fname in
  match opt with
  | None -> Ok None
  | Some data -> (
      RsaPrivateKey.of_octets data |> function
      | Error e -> Error e
      | Ok v -> Ok (Some v))