-module(yodel@format).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/yodel/format.gleam").
-export([get_format/4]).
-export_type([format_detector/0]).

-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 format_detector() :: {format_detector,
        binary(),
        fun((yodel@input:input()) -> yodel@options:format())}.

-file("src/yodel/format.gleam", 32).
-spec detect_format(yodel@input:input(), list(format_detector())) -> yodel@options:format().
detect_format(Input, Formats) ->
    gleam@list:fold(Formats, auto, fun(Acc, Format) -> case Acc of
                auto ->
                    (erlang:element(3, Format))(Input);

                _ ->
                    Acc
            end end).

-file("src/yodel/format.gleam", 16).
?DOC(
    " if the user specified a format, use it\n"
    " otherwise, try to detect the format from the input\n"
    " if that fails, try to detect the format from the content\n"
    " and if that fails, return `Auto` because we didn't figure it out\n"
).
-spec get_format(
    binary(),
    binary(),
    yodel@options:options(),
    list(format_detector())
) -> yodel@options:format().
get_format(Input, Content, Options, Formats) ->
    case yodel@options:get_format(Options) of
        auto ->
            case begin
                _pipe = Input,
                _pipe@1 = yodel@input:detect_input(_pipe),
                detect_format(_pipe@1, Formats)
            end of
                auto ->
                    _pipe@2 = Content,
                    _pipe@3 = yodel@input:detect_input(_pipe@2),
                    detect_format(_pipe@3, Formats);

                Format ->
                    Format
            end;

        Format@1 ->
            Format@1
    end.