fio

-module(fio@json).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/fio/json.gleam").
-export([read_json/2, write_json_atomic/3]).
-export_type([json_error/1]).

-if(?OTP_RELEASE >= 27).
-define(MODULEDOC(Str), -moduledoc(Str)).
-define(DOC(Str), -doc(Str)).
-else.
-define(MODULEDOC(Str), -compile([])).
-define(DOC(Str), -compile([])).
-endif.

-type json_error(FAB) :: {io_error, fio@error:fio_error()} | {parse_error, FAB}.

-file("src/fio/json.gleam", 49).
?DOC(
    " Read a file and decode its content with `decoder`.\n"
    "\n"
    " Returns `Error(IoError(_))` on I/O failure and\n"
    " `Error(ParseError(_))` when the decoder rejects the content.\n"
    "\n"
    " ```gleam\n"
    " fjson.read_json(\"settings.json\", my_decoder)\n"
    " // Ok(settings) | Error(IoError(Enoent)) | Error(ParseError(...))\n"
    " ```\n"
).
-spec read_json(binary(), fun((binary()) -> {ok, FAC} | {error, FAD})) -> {ok,
        FAC} |
    {error, json_error(FAD)}.
read_json(Path, Decoder) ->
    case fio:read(Path) of
        {error, E} ->
            {error, {io_error, E}};

        {ok, Content} ->
            case Decoder(Content) of
                {error, E@1} ->
                    {error, {parse_error, E@1}};

                {ok, Value} ->
                    {ok, Value}
            end
    end.

-file("src/fio/json.gleam", 71).
?DOC(
    " Encode `value` with `encoder` and write the result atomically to `path`.\n"
    "\n"
    " Uses `fio.write_atomic` under the hood, so readers never observe\n"
    " partial content.\n"
    "\n"
    " ```gleam\n"
    " fjson.write_json_atomic(\"settings.json\", settings, my_encoder)\n"
    " ```\n"
).
-spec write_json_atomic(binary(), FAJ, fun((FAJ) -> binary())) -> {ok, nil} |
    {error, fio@error:fio_error()}.
write_json_atomic(Path, Value, Encoder) ->
    fio:write_atomic(Path, Encoder(Value)).