playground

-module(robot_simulator).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch]).

-export([create/2, move/3]).
-export_type([direction/0, position/0, robot/0]).

-type direction() :: north | east | south | west.

-type position() :: {position, integer(), integer()}.

-type robot() :: {robot, direction(), position()}.

-file("/Users/bradleymehder/Developer/Frameworks/Gleam/playground/src/robot_simulator.gleam", 19).
-spec create(direction(), position()) -> robot().
create(Direction, Position) ->
    {robot, Direction, Position}.

-file("/Users/bradleymehder/Developer/Frameworks/Gleam/playground/src/robot_simulator.gleam", 44).
-spec turn_right(robot()) -> robot().
turn_right(Robot) ->
    case erlang:element(2, Robot) of
        north ->
            erlang:setelement(2, Robot, east);

        east ->
            erlang:setelement(2, Robot, south);

        south ->
            erlang:setelement(2, Robot, west);

        west ->
            erlang:setelement(2, Robot, north)
    end.

-file("/Users/bradleymehder/Developer/Frameworks/Gleam/playground/src/robot_simulator.gleam", 53).
-spec turn_left(robot()) -> robot().
turn_left(Robot) ->
    case erlang:element(2, Robot) of
        north ->
            erlang:setelement(2, Robot, west);

        east ->
            erlang:setelement(2, Robot, north);

        south ->
            erlang:setelement(2, Robot, east);

        west ->
            erlang:setelement(2, Robot, south)
    end.

-file("/Users/bradleymehder/Developer/Frameworks/Gleam/playground/src/robot_simulator.gleam", 62).
-spec advance(robot()) -> robot().
advance(Robot) ->
    {position, X, Y} = erlang:element(3, Robot),
    case erlang:element(2, Robot) of
        north ->
            erlang:setelement(3, Robot, {position, X, Y + 1});

        east ->
            erlang:setelement(3, Robot, {position, X + 1, Y});

        south ->
            erlang:setelement(3, Robot, {position, X, Y - 1});

        west ->
            erlang:setelement(3, Robot, {position, X - 1, Y})
    end.

-file("/Users/bradleymehder/Developer/Frameworks/Gleam/playground/src/robot_simulator.gleam", 23).
-spec move(direction(), position(), binary()) -> robot().
move(Direction, Position, Instructions) ->
    Robot = create(Direction, Position),
    Move_folder = fun(Robot@1, Instruction) -> case Instruction of
            <<"R"/utf8>> ->
                turn_right(Robot@1);

            <<"L"/utf8>> ->
                turn_left(Robot@1);

            <<"A"/utf8>> ->
                advance(Robot@1);

            _ ->
                erlang:error(#{gleam_error => panic,
                        message => <<"unreachable"/utf8>>,
                        module => <<"robot_simulator"/utf8>>,
                        function => <<"move"/utf8>>,
                        line => 35})
        end end,
    _pipe = Instructions,
    _pipe@1 = gleam@string:to_graphemes(_pipe),
    gleam@list:fold(_pipe@1, Robot, Move_folder).