-module(gleeth@rpc@batch).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/gleeth/rpc/batch.gleam").
-export([new/0, add/3, add_method/3, execute_strings/2, execute_raw/2]).
-export_type([batch/0, batch_request/0, parsed_response/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(
    " Batch JSON-RPC requests into a single HTTP call.\n"
    "\n"
    " Reduces HTTP overhead when making multiple independent queries by sending\n"
    " them as a JSON array per the JSON-RPC batch specification.\n"
    "\n"
    " ## Examples\n"
    "\n"
    " ```gleam\n"
    " let assert Ok(results) =\n"
    "   batch.new()\n"
    "   |> batch.add(\"eth_blockNumber\", [])\n"
    "   |> batch.add(\"eth_gasPrice\", [])\n"
    "   |> batch.execute_strings(provider)\n"
    "\n"
    " // results: [Ok(\"0x1234\"), Ok(\"0x3b9aca00\")]\n"
    " ```\n"
).

-type batch() :: {batch, list(batch_request())}.

-opaque batch_request() :: {batch_request,
        binary(),
        list(gleam@json:json()),
        integer()}.

-type parsed_response() :: {parsed_response,
        integer(),
        binary(),
        binary(),
        boolean()}.

-file("src/gleeth/rpc/batch.gleam", 38).
?DOC(" Create an empty batch.\n").
-spec new() -> batch().
new() ->
    {batch, []}.

-file("src/gleeth/rpc/batch.gleam", 43).
?DOC(" Add a raw method name and params to the batch.\n").
-spec add(batch(), binary(), list(gleam@json:json())) -> batch().
add(Batch, Method, Params) ->
    Id = erlang:length(erlang:element(2, Batch)) + 1,
    {batch, [{batch_request, Method, Params, Id} | erlang:element(2, Batch)]}.

-file("src/gleeth/rpc/batch.gleam", 52).
?DOC(" Add a request using an EthMethod value.\n").
-spec add_method(
    batch(),
    gleeth@rpc@types:eth_method(),
    list(gleam@json:json())
) -> batch().
add_method(Batch, Method, Params) ->
    add(Batch, gleeth@rpc@types:method_to_string(Method), Params).

-file("src/gleeth/rpc/batch.gleam", 111).
-spec encode_batch(list(batch_request())) -> binary().
encode_batch(Requests) ->
    gleam@json:to_string(
        gleam@json:array(
            Requests,
            fun(Req) ->
                gleam@json:object(
                    [{<<"jsonrpc"/utf8>>, gleam@json:string(<<"2.0"/utf8>>)},
                        {<<"method"/utf8>>,
                            gleam@json:string(erlang:element(2, Req))},
                        {<<"params"/utf8>>,
                            gleam@json:array(
                                erlang:element(3, Req),
                                fun(X) -> X end
                            )},
                        {<<"id"/utf8>>, gleam@json:int(erlang:element(4, Req))}]
                )
            end
        )
    ).

-file("src/gleeth/rpc/batch.gleam", 173).
-spec error_message_decoder() -> gleam@dynamic@decode:decoder(binary()).
error_message_decoder() ->
    gleam@dynamic@decode:one_of(
        begin
            gleam@dynamic@decode:field(
                <<"message"/utf8>>,
                {decoder, fun gleam@dynamic@decode:decode_string/1},
                fun(Msg) -> gleam@dynamic@decode:success(Msg) end
            )
        end,
        [gleam@dynamic@decode:map(
                {decoder, fun gleam@dynamic@decode:decode_string/1},
                fun(S) -> S end
            )]
    ).

-file("src/gleeth/rpc/batch.gleam", 144).
-spec response_decoder() -> gleam@dynamic@decode:decoder(parsed_response()).
response_decoder() ->
    gleam@dynamic@decode:field(
        <<"id"/utf8>>,
        {decoder, fun gleam@dynamic@decode:decode_int/1},
        fun(Id) ->
            gleam@dynamic@decode:optional_field(
                <<"result"/utf8>>,
                <<""/utf8>>,
                gleam@dynamic@decode:one_of(
                    {decoder, fun gleam@dynamic@decode:decode_string/1},
                    [gleam@dynamic@decode:map(
                            {decoder, fun gleam@dynamic@decode:decode_int/1},
                            fun(N) -> gleam@string:inspect(N) end
                        ),
                        gleam@dynamic@decode:map(
                            {decoder, fun gleam@dynamic@decode:decode_bool/1},
                            fun(B) -> case B of
                                    true ->
                                        <<"true"/utf8>>;

                                    false ->
                                        <<"false"/utf8>>
                                end end
                        ),
                        gleam@dynamic@decode:success(<<""/utf8>>)]
                ),
                fun(Result) ->
                    gleam@dynamic@decode:optional_field(
                        <<"error"/utf8>>,
                        <<""/utf8>>,
                        error_message_decoder(),
                        fun(Error_msg) ->
                            Has_result = Error_msg =:= <<""/utf8>>,
                            gleam@dynamic@decode:success(
                                {parsed_response,
                                    Id,
                                    Result,
                                    Error_msg,
                                    Has_result}
                            )
                        end
                    )
                end
            )
        end
    ).

-file("src/gleeth/rpc/batch.gleam", 133).
-spec parse_batch_response(binary()) -> {ok, list(parsed_response())} |
    {error, gleeth@rpc@types:gleeth_error()}.
parse_batch_response(Body) ->
    Decoder = gleam@dynamic@decode:list(response_decoder()),
    case gleam@json:parse(Body, Decoder) of
        {ok, Results} ->
            {ok, Results};

        {error, _} ->
            {error,
                {parse_error,
                    <<"Failed to parse batch JSON-RPC response"/utf8>>}}
    end.

-file("src/gleeth/rpc/batch.gleam", 234).
-spec find_response(list(parsed_response()), integer()) -> {ok,
        parsed_response()} |
    {error, nil}.
find_response(Responses, Id) ->
    gleam@list:find(Responses, fun(R) -> erlang:element(2, R) =:= Id end).

-file("src/gleeth/rpc/batch.gleam", 191).
-spec match_and_decode_strings(list(parsed_response()), list(batch_request())) -> list({ok,
        binary()} |
    {error, gleeth@rpc@types:gleeth_error()}).
match_and_decode_strings(Responses, Requests) ->
    gleam@list:map(
        Requests,
        fun(Req) -> case find_response(Responses, erlang:element(4, Req)) of
                {ok, Parsed} ->
                    case erlang:element(5, Parsed) of
                        true ->
                            {ok, erlang:element(3, Parsed)};

                        false ->
                            {error,
                                {rpc_error,
                                    <<"RPC Error: "/utf8,
                                        (erlang:element(4, Parsed))/binary>>}}
                    end;

                {error, _} ->
                    {error,
                        {parse_error, <<"No response for batch request"/utf8>>}}
            end end
    ).

-file("src/gleeth/rpc/batch.gleam", 63).
?DOC(
    " Execute the batch and decode each response as a string.\n"
    " Returns one `Result(String, GleethError)` per request, in order.\n"
    " This is the most common use case - batching simple hex-returning RPC calls.\n"
).
-spec execute_strings(batch(), gleeth@provider:provider()) -> {ok,
        list({ok, binary()} | {error, gleeth@rpc@types:gleeth_error()})} |
    {error, gleeth@rpc@types:gleeth_error()}.
execute_strings(Batch, Provider) ->
    Requests = lists:reverse(erlang:element(2, Batch)),
    case Requests of
        [] ->
            {ok, []};

        _ ->
            Batch_json = encode_batch(Requests),
            Rpc_url = gleeth@provider:rpc_url(Provider),
            gleam@result:'try'(
                gleeth@rpc@client:make_batch_request(Rpc_url, Batch_json),
                fun(Response_body) ->
                    gleam@result:'try'(
                        parse_batch_response(Response_body),
                        fun(Parsed) ->
                            {ok, match_and_decode_strings(Parsed, Requests)}
                        end
                    )
                end
            )
    end.

-file("src/gleeth/rpc/batch.gleam", 207).
-spec match_raw(list(parsed_response()), list(batch_request())) -> list({ok,
        binary()} |
    {error, gleeth@rpc@types:gleeth_error()}).
match_raw(Responses, Requests) ->
    gleam@list:map(
        Requests,
        fun(Req) -> case find_response(Responses, erlang:element(4, Req)) of
                {ok, Parsed} ->
                    case erlang:element(5, Parsed) of
                        true ->
                            Body = gleam@json:to_string(
                                gleam@json:object(
                                    [{<<"jsonrpc"/utf8>>,
                                            gleam@json:string(<<"2.0"/utf8>>)},
                                        {<<"id"/utf8>>,
                                            gleam@json:int(
                                                erlang:element(2, Parsed)
                                            )},
                                        {<<"result"/utf8>>,
                                            gleam@json:string(
                                                erlang:element(3, Parsed)
                                            )}]
                                )
                            ),
                            {ok, Body};

                        false ->
                            {error,
                                {rpc_error,
                                    <<"RPC Error: "/utf8,
                                        (erlang:element(4, Parsed))/binary>>}}
                    end;

                {error, _} ->
                    {error,
                        {parse_error, <<"No response for batch request"/utf8>>}}
            end end
    ).

-file("src/gleeth/rpc/batch.gleam", 87).
?DOC(
    " Execute the batch and return raw JSON response bodies per request.\n"
    " Each string is the full `{\"jsonrpc\":\"2.0\",\"id\":N,\"result\":...}` for that\n"
    " request, suitable for passing to `response_utils.decode_rpc_response`\n"
    " with a custom decoder.\n"
).
-spec execute_raw(batch(), gleeth@provider:provider()) -> {ok,
        list({ok, binary()} | {error, gleeth@rpc@types:gleeth_error()})} |
    {error, gleeth@rpc@types:gleeth_error()}.
execute_raw(Batch, Provider) ->
    Requests = lists:reverse(erlang:element(2, Batch)),
    case Requests of
        [] ->
            {ok, []};

        _ ->
            Batch_json = encode_batch(Requests),
            Rpc_url = gleeth@provider:rpc_url(Provider),
            gleam@result:'try'(
                gleeth@rpc@client:make_batch_request(Rpc_url, Batch_json),
                fun(Response_body) ->
                    gleam@result:'try'(
                        parse_batch_response(Response_body),
                        fun(Parsed) -> {ok, match_raw(Parsed, Requests)} end
                    )
                end
            )
    end.