-module(fio@recursive).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/fio/recursive.gleam").
-export([list_recursive/1, copy_directory/2]).

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

-file("src/fio/recursive.gleam", 13).
-spec inode_key(fio@types:file_info(), binary()) -> binary().
inode_key(Info, Fallback_path) ->
    case erlang:element(5, Info) of
        0 ->
            Fallback_path;

        _ ->
            <<<<<<"dev:"/utf8,
                        (erlang:integer_to_binary(erlang:element(8, Info)))/binary>>/binary,
                    ";ino:"/utf8>>/binary,
                (erlang:integer_to_binary(erlang:element(5, Info)))/binary>>
    end.

-file("src/fio/recursive.gleam", 45).
-spec do_list_recursive(
    binary(),
    binary(),
    gleam@set:set(binary()),
    list(binary())
) -> {ok, list(binary())} | {error, fio@error:fio_error()}.
do_list_recursive(Root, Current_rel, Visited, Acc) ->
    Current_dir = case Current_rel of
        <<""/utf8>> ->
            Root;

        Rel ->
            fio@path:join(Root, Rel)
    end,
    gleam@result:'try'(
        fio@internal@io:list_directory(Current_dir),
        fun(Items) ->
            gleam@list:try_fold(
                Items,
                Acc,
                fun(Inner_acc, Item) ->
                    Item_rel = case Current_rel of
                        <<""/utf8>> ->
                            Item;

                        Rel@1 ->
                            fio@path:join(Rel@1, Item)
                    end,
                    Full_path = fio@path:join(Root, Item_rel),
                    gleam@result:'try'(
                        fio@internal@io:is_directory(Full_path),
                        fun(Is_dir) -> case Is_dir of
                                false ->
                                    {ok, [Item_rel | Inner_acc]};

                                true ->
                                    gleam@result:'try'(
                                        fio@internal@io:file_info(Full_path),
                                        fun(Info) ->
                                            Key = inode_key(Info, Full_path),
                                            case gleam@set:contains(
                                                Visited,
                                                Key
                                            ) of
                                                true ->
                                                    {ok, [Item_rel | Inner_acc]};

                                                false ->
                                                    do_list_recursive(
                                                        Root,
                                                        Item_rel,
                                                        gleam@set:insert(
                                                            Visited,
                                                            Key
                                                        ),
                                                        [Item_rel | Inner_acc]
                                                    )
                                            end
                                        end
                                    )
                            end end
                    )
                end
            )
        end
    ).

-file("src/fio/recursive.gleam", 29).
?DOC(
    " Recursively list files and directories (paths relative to `path`).\n"
    "\n"
    " Uses a flat string accumulator for O(n) traversal.\n"
    "\n"
    " **Symlink loop safety**: before descending into any directory, its real\n"
    " `(dev, inode)` pair (obtained via `stat`, which follows symlinks) is\n"
    " checked against the `visited` set. If already seen, the entry is listed\n"
    " but not descended into, breaking any A->B->A or deeper circular chains.\n"
).
-spec list_recursive(binary()) -> {ok, list(binary())} |
    {error, fio@error:fio_error()}.
list_recursive(Path) ->
    gleam@result:'try'(
        fio@internal@io:is_directory(Path),
        fun(Is_dir) -> case Is_dir of
                true ->
                    gleam@result:'try'(
                        fio@internal@io:file_info(Path),
                        fun(Root_info) ->
                            Visited = gleam@set:from_list(
                                [inode_key(Root_info, Path)]
                            ),
                            gleam@result:'try'(
                                do_list_recursive(
                                    Path,
                                    <<""/utf8>>,
                                    Visited,
                                    []
                                ),
                                fun(Acc) -> {ok, lists:reverse(Acc)} end
                            )
                        end
                    );

                false ->
                    {error, enotdir}
            end end
    ).

-file("src/fio/recursive.gleam", 102).
-spec do_copy_directory(binary(), binary(), gleam@set:set(binary())) -> {ok,
        nil} |
    {error, fio@error:fio_error()}.
do_copy_directory(Src, Dest, Visited) ->
    gleam@result:'try'(
        fio@internal@io:create_directory_all(Dest),
        fun(_) ->
            gleam@result:'try'(
                fio@internal@io:list_directory(Src),
                fun(Items) ->
                    gleam@list:try_each(
                        Items,
                        fun(Item) ->
                            Src_path = fio@path:join(Src, Item),
                            Dest_path = fio@path:join(Dest, Item),
                            gleam@result:'try'(
                                fio@internal@io:is_directory(Src_path),
                                fun(Is_dir_item) -> case Is_dir_item of
                                        false ->
                                            fio@internal@io:copy_file(
                                                Src_path,
                                                Dest_path
                                            );

                                        true ->
                                            gleam@result:'try'(
                                                fio@internal@io:file_info(
                                                    Src_path
                                                ),
                                                fun(Info) ->
                                                    Key = inode_key(
                                                        Info,
                                                        Src_path
                                                    ),
                                                    case gleam@set:contains(
                                                        Visited,
                                                        Key
                                                    ) of
                                                        true ->
                                                            {ok, nil};

                                                        false ->
                                                            do_copy_directory(
                                                                Src_path,
                                                                Dest_path,
                                                                gleam@set:insert(
                                                                    Visited,
                                                                    Key
                                                                )
                                                            )
                                                    end
                                                end
                                            )
                                    end end
                            )
                        end
                    )
                end
            )
        end
    ).

-file("src/fio/recursive.gleam", 90).
?DOC(
    " Recursively copy `src` directory into `dest` (creates parents).\n"
    "\n"
    " **Symlink loop safety**: directory symlinks whose resolved inode has\n"
    " already been visited are skipped silently rather than followed forever.\n"
).
-spec copy_directory(binary(), binary()) -> {ok, nil} |
    {error, fio@error:fio_error()}.
copy_directory(Src, Dest) ->
    gleam@result:'try'(
        fio@internal@io:is_directory(Src),
        fun(Is_dir) -> case Is_dir of
                false ->
                    {error, enotdir};

                true ->
                    gleam@result:'try'(
                        fio@internal@io:file_info(Src),
                        fun(Root_info) ->
                            Visited = gleam@set:from_list(
                                [inode_key(Root_info, Src)]
                            ),
                            do_copy_directory(Src, Dest, Visited)
                        end
                    )
            end end
    ).