-module(handles@internal@tokenizer).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch]).

-export([run/3]).
-export_type([token/0]).

-type token() :: {constant, integer(), binary()} |
    {property, integer(), list(binary())} |
    {partial, integer(), binary(), list(binary())} |
    {if_block_start, integer(), list(binary())} |
    {if_block_end, integer()} |
    {unless_block_start, integer(), list(binary())} |
    {unless_block_end, integer()} |
    {each_block_start, integer(), list(binary())} |
    {each_block_end, integer()}.

-spec split_body(binary()) -> list(binary()).
split_body(Body) ->
    _pipe = Body,
    _pipe@1 = gleam@string:trim(_pipe),
    _pipe@2 = gleam@string:split(_pipe@1, <<" "/utf8>>),
    gleam@list:filter(
        _pipe@2,
        fun(It) ->
            begin
                _pipe@3 = It,
                _pipe@4 = gleam@string:trim(_pipe@3),
                gleam@string:length(_pipe@4)
            end
            > 0
        end
    ).

-spec split_arg(binary()) -> list(binary()).
split_arg(Arg) ->
    case begin
        _pipe = Arg,
        gleam@string:trim(_pipe)
    end of
        <<"."/utf8>> ->
            [];

        Arg@1 ->
            gleam@string:split(Arg@1, <<"."/utf8>>)
    end.

-spec capture_tag_body(binary(), integer()) -> {ok, {binary(), binary()}} |
    {error, handles@error:tokenizer_error()}.
capture_tag_body(Input, Index) ->
    _pipe = Input,
    _pipe@1 = gleam@string:split_once(_pipe, <<"}}"/utf8>>),
    gleam@result:map_error(_pipe@1, fun(_) -> {unbalanced_tag, Index + 2} end).

-spec run(binary(), integer(), list(token())) -> {ok, list(token())} |
    {error, handles@error:tokenizer_error()}.
run(Input, Index, Tokens) ->
    case Input of
        <<"{{>"/utf8, Rest/binary>> ->
            gleam@result:'try'(
                capture_tag_body(Rest, Index),
                fun(_use0) ->
                    {Body, Rest@1} = _use0,
                    case split_body(Body) of
                        [] ->
                            {error, {missing_partial_id, Index + 2}};

                        [_] ->
                            {error, {missing_argument, Index + 2}};

                        [Id, Arg] ->
                            run(
                                Rest@1,
                                (Index + gleam@string:length(<<"{{>}}"/utf8>>))
                                + gleam@string:length(Body),
                                [{partial, Index + 2, Id, split_arg(Arg)} |
                                    Tokens]
                            );

                        _ ->
                            {error, {unexpected_multiple_arguments, Index + 2}}
                    end
                end
            );

        <<"{{#"/utf8, Rest@2/binary>> ->
            gleam@result:'try'(
                capture_tag_body(Rest@2, Index),
                fun(_use0@1) ->
                    {Body@1, Rest@3} = _use0@1,
                    case split_body(Body@1) of
                        [] ->
                            {error, {missing_block_kind, Index + 2}};

                        [_] ->
                            {error, {missing_argument, Index + 2}};

                        [Kind, Arg@1] ->
                            case Kind of
                                <<"if"/utf8>> ->
                                    run(
                                        Rest@3,
                                        (Index + 5) + gleam@string:length(
                                            Body@1
                                        ),
                                        [{if_block_start,
                                                Index + 2,
                                                split_arg(Arg@1)} |
                                            Tokens]
                                    );

                                <<"unless"/utf8>> ->
                                    run(
                                        Rest@3,
                                        (Index + 5) + gleam@string:length(
                                            Body@1
                                        ),
                                        [{unless_block_start,
                                                Index + 2,
                                                split_arg(Arg@1)} |
                                            Tokens]
                                    );

                                <<"each"/utf8>> ->
                                    run(
                                        Rest@3,
                                        (Index + 5) + gleam@string:length(
                                            Body@1
                                        ),
                                        [{each_block_start,
                                                Index + 2,
                                                split_arg(Arg@1)} |
                                            Tokens]
                                    );

                                _ ->
                                    {error, {unexpected_block_kind, Index}}
                            end;

                        _ ->
                            {error, {unexpected_multiple_arguments, Index + 2}}
                    end
                end
            );

        <<"{{/"/utf8, Rest@4/binary>> ->
            gleam@result:'try'(
                capture_tag_body(Rest@4, Index),
                fun(_use0@2) ->
                    {Body@2, Rest@5} = _use0@2,
                    case split_body(Body@2) of
                        [] ->
                            {error, {missing_block_kind, Index + 2}};

                        [_, _] ->
                            {error, {unexpected_argument, Index + 2}};

                        [Kind@1] ->
                            case Kind@1 of
                                <<"if"/utf8>> ->
                                    run(
                                        Rest@5,
                                        (Index + 5) + gleam@string:length(
                                            Body@2
                                        ),
                                        [{if_block_end, Index + 2} | Tokens]
                                    );

                                <<"unless"/utf8>> ->
                                    run(
                                        Rest@5,
                                        (Index + 5) + gleam@string:length(
                                            Body@2
                                        ),
                                        [{unless_block_end, Index + 2} | Tokens]
                                    );

                                <<"each"/utf8>> ->
                                    run(
                                        Rest@5,
                                        (Index + 5) + gleam@string:length(
                                            Body@2
                                        ),
                                        [{each_block_end, Index + 2} | Tokens]
                                    );

                                _ ->
                                    {error, {unexpected_block_kind, Index}}
                            end;

                        _ ->
                            {error, {unexpected_argument, Index + 2}}
                    end
                end
            );

        <<"{{"/utf8, Rest@6/binary>> ->
            gleam@result:'try'(
                capture_tag_body(Rest@6, Index),
                fun(_use0@3) ->
                    {Body@3, Rest@7} = _use0@3,
                    case split_body(Body@3) of
                        [] ->
                            {error, {missing_argument, Index + 2}};

                        [Arg@2] ->
                            run(
                                Rest@7,
                                (Index + 4) + gleam@string:length(Body@3),
                                [{property, Index + 2, split_arg(Arg@2)} |
                                    Tokens]
                            );

                        _ ->
                            {error, {unexpected_multiple_arguments, Index + 2}}
                    end
                end
            );

        _ ->
            case begin
                _pipe = Input,
                gleam@string:split_once(_pipe, <<"{{"/utf8>>)
            end of
                {ok, {Str, Rest@8}} ->
                    run(
                        <<"{{"/utf8, Rest@8/binary>>,
                        Index + gleam@string:length(Str),
                        [{constant, Index, Str} | Tokens]
                    );

                _ ->
                    case Input of
                        <<""/utf8>> ->
                            {ok, lists:reverse(Tokens)};

                        Str@1 ->
                            {ok,
                                lists:reverse(
                                    [{constant, Index, Str@1} | Tokens]
                                )}
                    end
            end
    end.