-module(gleam@result).
-compile(no_auto_import).

-export([is_ok/1, is_error/1, map/2, map_error/2, flatten/1, then/2, unwrap/2, lazy_unwrap/2, nil_error/1, 'or'/2, lazy_or/2, all/1, replace_error/2]).

-spec is_ok({ok, any()} | {error, any()}) -> boolean().
is_ok(Result) ->
    case Result of
        {error, _} ->
            false;

        {ok, _} ->
            true
    end.

-spec is_error({ok, any()} | {error, any()}) -> boolean().
is_error(Result) ->
    case Result of
        {ok, _} ->
            false;

        {error, _} ->
            true
    end.

-spec map({ok, BZS} | {error, BZT}, fun((BZS) -> BZW)) -> {ok, BZW} |
    {error, BZT}.
map(Result, Fun) ->
    case Result of
        {ok, X} ->
            {ok, Fun(X)};

        {error, E} ->
            {error, E}
    end.

-spec map_error({ok, BZZ} | {error, CAA}, fun((CAA) -> CAD)) -> {ok, BZZ} |
    {error, CAD}.
map_error(Result, Fun) ->
    case Result of
        {ok, X} ->
            {ok, X};

        {error, Error} ->
            {error, Fun(Error)}
    end.

-spec flatten({ok, {ok, CAG} | {error, CAH}} | {error, CAH}) -> {ok, CAG} |
    {error, CAH}.
flatten(Result) ->
    case Result of
        {ok, X} ->
            X;

        {error, Error} ->
            {error, Error}
    end.

-spec then({ok, CAO} | {error, CAP}, fun((CAO) -> {ok, CAS} | {error, CAP})) -> {ok,
                                                                                 CAS} |
    {error, CAP}.
then(Result, Fun) ->
    case Result of
        {ok, X} ->
            Fun(X);

        {error, E} ->
            {error, E}
    end.

-spec unwrap({ok, CAX} | {error, any()}, CAX) -> CAX.
unwrap(Result, Default) ->
    case Result of
        {ok, V} ->
            V;

        {error, _} ->
            Default
    end.

-spec lazy_unwrap({ok, CBB} | {error, any()}, fun(() -> CBB)) -> CBB.
lazy_unwrap(Result, Default) ->
    case Result of
        {ok, V} ->
            V;

        {error, _} ->
            Default()
    end.

-spec nil_error({ok, CBF} | {error, any()}) -> {ok, CBF} | {error, nil}.
nil_error(Result) ->
    map_error(Result, fun(_) -> nil end).

-spec 'or'({ok, CBL} | {error, CBM}, {ok, CBL} | {error, CBM}) -> {ok, CBL} |
    {error, CBM}.
'or'(First, Second) ->
    case First of
        {ok, _} ->
            First;

        {error, _} ->
            Second
    end.

-spec lazy_or({ok, CBT} | {error, CBU}, fun(() -> {ok, CBT} | {error, CBU})) -> {ok,
                                                                                 CBT} |
    {error, CBU}.
lazy_or(First, Second) ->
    case First of
        {ok, _} ->
            First;

        {error, _} ->
            Second()
    end.

-spec all(list({ok, CCB} | {error, CCC})) -> {ok, list(CCB)} | {error, CCC}.
all(Results) ->
    gleam@list:try_map(Results, fun(X) -> X end).

-spec replace_error({ok, CCJ} | {error, any()}, CCN) -> {ok, CCJ} | {error, CCN}.
replace_error(Result, Error) ->
    map_error(Result, fun(_) -> Error end).