-module(gleeth@multicall).
-compile([no_auto_import, nowarn_unused_vars, nowarn_unused_function, nowarn_nomatch, inline]).
-define(FILEPATH, "src/gleeth/multicall.gleam").
-export([new/0, add/3, try_add/3, execute_at/3, execute/2]).
-export_type([multicall/0, call/0, call_result/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(
    " Multicall3 batching for efficient contract reads.\n"
    "\n"
    " Batches multiple contract read calls into a single `eth_call` using the\n"
    " canonical Multicall3 contract (deployed at the same address on all major\n"
    " chains). This reduces RPC round trips when reading state from multiple\n"
    " contracts.\n"
    "\n"
    " ## Examples\n"
    "\n"
    " ```gleam\n"
    " // Read 3 balances in a single RPC call\n"
    " let assert Ok(results) =\n"
    "   multicall.new()\n"
    "   |> multicall.add(usdc_address, balance_of_calldata_1)\n"
    "   |> multicall.add(usdc_address, balance_of_calldata_2)\n"
    "   |> multicall.add(dai_address, balance_of_calldata_3)\n"
    "   |> multicall.execute(provider)\n"
    " ```\n"
).

-type multicall() :: {multicall, list(call())}.

-type call() :: {call, binary(), binary(), boolean()}.

-type call_result() :: {call_success, binary()} | {call_failure, binary()}.

-file("src/gleeth/multicall.gleam", 52).
?DOC(" Create an empty multicall batch.\n").
-spec new() -> multicall().
new() ->
    {multicall, []}.

-file("src/gleeth/multicall.gleam", 64).
?DOC(
    " Add a call that must succeed (reverts the whole batch on failure).\n"
    "\n"
    " ## Examples\n"
    "\n"
    " ```gleam\n"
    " multicall.new()\n"
    " |> multicall.add(\"0xA0b8...\", \"0x70a08231...\")\n"
    " ```\n"
).
-spec add(multicall(), binary(), binary()) -> multicall().
add(Batch, Target, Calldata) ->
    {multicall, [{call, Target, Calldata, false} | erlang:element(2, Batch)]}.

-file("src/gleeth/multicall.gleam", 79).
?DOC(
    " Add a call that is allowed to fail without reverting the batch.\n"
    "\n"
    " ## Examples\n"
    "\n"
    " ```gleam\n"
    " multicall.new()\n"
    " |> multicall.try_add(\"0xA0b8...\", \"0x70a08231...\")\n"
    " ```\n"
).
-spec try_add(multicall(), binary(), binary()) -> multicall().
try_add(Batch, Target, Calldata) ->
    {multicall, [{call, Target, Calldata, true} | erlang:element(2, Batch)]}.

-file("src/gleeth/multicall.gleam", 145).
-spec encode_aggregate3(list(call())) -> {ok, binary()} |
    {error, gleeth@rpc@types:gleeth_error()}.
encode_aggregate3(Calls) ->
    gleam@result:'try'(
        gleam@list:try_map(
            Calls,
            fun(C) -> case gleeth@utils@hex:decode(erlang:element(3, C)) of
                    {ok, Calldata_bytes} ->
                        {ok,
                            {tuple_value,
                                [{address_value, erlang:element(2, C)},
                                    {bool_value, erlang:element(4, C)},
                                    {bytes_value, Calldata_bytes}]}};

                    {error, _} ->
                        {error,
                            {parse_error,
                                <<"Invalid calldata hex: "/utf8,
                                    (erlang:element(3, C))/binary>>}}
                end end
        ),
        fun(Call_values) ->
            Call_type = {tuple, [address, bool, bytes]},
            Array_type = {array, Call_type},
            case gleeth@ethereum@abi@encode:encode(
                [{Array_type, {array_value, Call_values}}]
            ) of
                {ok, Encoded} ->
                    Encoded_hex = string:lowercase(
                        gleam_stdlib:base16_encode(Encoded)
                    ),
                    {ok, <<"0x82ad56cb"/utf8, Encoded_hex/binary>>};

                {error, Err} ->
                    {error, {abi_err, Err}}
            end
        end
    ).

-file("src/gleeth/multicall.gleam", 183).
-spec decode_aggregate3_result(binary()) -> {ok, list(call_result())} |
    {error, gleeth@rpc@types:gleeth_error()}.
decode_aggregate3_result(Result_hex) ->
    case gleeth@utils@hex:decode(Result_hex) of
        {ok, Bytes} ->
            Result_type = {array, {tuple, [bool, bytes]}},
            case gleeth@ethereum@abi@decode:decode([Result_type], Bytes) of
                {ok, [{array_value, Items}]} ->
                    {ok, gleam@list:map(Items, fun(Item) -> case Item of
                                    {tuple_value,
                                        [{bool_value, Success},
                                            {bytes_value, Data}]} ->
                                        Data_hex = <<"0x"/utf8,
                                            (string:lowercase(
                                                gleam_stdlib:base16_encode(Data)
                                            ))/binary>>,
                                        case Success of
                                            true ->
                                                {call_success, Data_hex};

                                            false ->
                                                {call_failure, Data_hex}
                                        end;

                                    _ ->
                                        {call_failure, <<"0x"/utf8>>}
                                end end)};

                {ok, _} ->
                    {error,
                        {parse_error,
                            <<"Unexpected multicall result shape"/utf8>>}};

                {error, Err} ->
                    {error, {abi_err, Err}}
            end;

        {error, _} ->
            {error, {parse_error, <<"Invalid hex in multicall result"/utf8>>}}
    end.

-file("src/gleeth/multicall.gleam", 119).
?DOC(
    " Execute using a custom Multicall3 address (for chains where it's deployed\n"
    " at a non-standard address).\n"
).
-spec execute_at(multicall(), gleeth@provider:provider(), binary()) -> {ok,
        list(call_result())} |
    {error, gleeth@rpc@types:gleeth_error()}.
execute_at(Batch, Provider, Address) ->
    Calls = lists:reverse(erlang:element(2, Batch)),
    case Calls of
        [] ->
            {ok, []};

        _ ->
            gleam@result:'try'(
                encode_aggregate3(Calls),
                fun(Calldata) ->
                    gleam@result:'try'(
                        gleeth@rpc@methods:call_contract(
                            Provider,
                            Address,
                            Calldata
                        ),
                        fun(Result_hex) ->
                            decode_aggregate3_result(Result_hex)
                        end
                    )
                end
            )
    end.

-file("src/gleeth/multicall.gleam", 98).
?DOC(
    " Execute the multicall batch using `aggregate3`.\n"
    " Returns one `CallResult` per call in the order they were added.\n"
    "\n"
    " ## Examples\n"
    "\n"
    " ```gleam\n"
    " let assert Ok(results) =\n"
    "   multicall.new()\n"
    "   |> multicall.add(usdc, calldata1)\n"
    "   |> multicall.add(usdc, calldata2)\n"
    "   |> multicall.execute(provider)\n"
    " ```\n"
).
-spec execute(multicall(), gleeth@provider:provider()) -> {ok,
        list(call_result())} |
    {error, gleeth@rpc@types:gleeth_error()}.
execute(Batch, Provider) ->
    Calls = lists:reverse(erlang:element(2, Batch)),
    case Calls of
        [] ->
            {ok, []};

        _ ->
            gleam@result:'try'(
                encode_aggregate3(Calls),
                fun(Calldata) ->
                    gleam@result:'try'(
                        gleeth@rpc@methods:call_contract(
                            Provider,
                            <<"0xcA11bde05977b3631167028862bE2a173976CA11"/utf8>>,
                            Calldata
                        ),
                        fun(Result_hex) ->
                            decode_aggregate3_result(Result_hex)
                        end
                    )
                end
            )
    end.