apiculture

-module(apiculture@alphabet).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/apiculture/alphabet.gleam").
-export([new_alphabet/1, characters/1, size/1]).
-export_type([alphabet/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.

?MODULEDOC(
    " Alphabet representation and validation.\n"
    "\n"
    " An alphabet is a validated set of graphemes for direct random character\n"
    " sampling. It is deliberately separate from an encoding, which transforms\n"
    " arbitrary bytes into text.\n"
).

-type alphabet() :: {alphabet, binary()}.

-file("src/apiculture/alphabet.gleam", 50).
-spec has_duplicates(list(binary())) -> boolean().
has_duplicates(Items) ->
    case Items of
        [] ->
            false;

        [First | Rest] ->
            case gleam@list:contains(Rest, First) of
                true ->
                    true;

                false ->
                    has_duplicates(Rest)
            end
    end.

-file("src/apiculture/alphabet.gleam", 21).
?DOC(
    " Creates a new alphabet from a string of characters.\n"
    "\n"
    " Returns an error if the alphabet is empty, has only one character,\n"
    " or contains duplicate characters.\n"
).
-spec new_alphabet(binary()) -> {ok, alphabet()} |
    {error, apiculture@error:error()}.
new_alphabet(Chars) ->
    Char_list = gleam@string:to_graphemes(Chars),
    case gleam@list:is_empty(Char_list) of
        true ->
            {error, empty_alphabet};

        false ->
            case erlang:length(Char_list) of
                1 ->
                    {error, single_character_alphabet};

                _ ->
                    case has_duplicates(Char_list) of
                        true ->
                            {error, duplicate_characters};

                        false ->
                            {ok, {alphabet, Chars}}
                    end
            end
    end.

-file("src/apiculture/alphabet.gleam", 41).
?DOC(" Returns the characters in the alphabet as a list of graphemes.\n").
-spec characters(alphabet()) -> list(binary()).
characters(Alphabet) ->
    gleam@string:to_graphemes(erlang:element(2, Alphabet)).

-file("src/apiculture/alphabet.gleam", 46).
?DOC(" Returns the size (number of characters) in the alphabet.\n").
-spec size(alphabet()) -> integer().
size(Alphabet) ->
    string:length(erlang:element(2, Alphabet)).