// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity >=0.5.0;
pragma experimental ABIEncoderV2;

/// @title Multicall2 - Aggregate results from multiple read-only function calls
/// @author Michael Elliot <mike@makerdao.com>
/// @author Joshua Levine <joshua@makerdao.com>
/// @author Nick Johnson <arachnid@notdot.net>

contract Multicall2 {
    struct Call {
        address target;
        bytes callData;
    }
    struct Result {
        bool success;
        bytes returnData;
    }

    function aggregate(Call[] memory calls) public returns (uint256 blockNumber, bytes[] memory returnData) {
        blockNumber = block.number;
        returnData = new bytes[](calls.length);
        for (uint256 i = 0; i < calls.length; i++) {
            (bool success, bytes memory ret) = calls[i].target.call(calls[i].callData);
            require(success, "Multicall aggregate: call failed");
            returnData[i] = ret;
        }
    }

    function tryAggregate(bool requireSuccess, Call[] memory calls) public returns (Result[] memory returnData) {
        returnData = new Result[](calls.length);
        for (uint256 i = 0; i < calls.length; i++) {
            (bool success, bytes memory ret) = calls[i].target.call(calls[i].callData);

            if (requireSuccess) {
                require(success, "Multicall2 aggregate: call failed");
            }

            returnData[i] = Result(success, ret);
        }
    }
}