// SPDX-License-Identifier: MIT
pragma solidity 0.8.17;

import {MulticallFailed} from "../libs/Errors.sol";

/// @notice Collection of Multicall utilities. Fork of Multicall3:
/// https://github.com/mds1/multicall/blob/master/src/Multicall3.sol
abstract contract MultiCallable {
    struct Call {
        bool allowFailure;
        bytes callData;
    }

    struct Result {
        bool success;
        bytes returnData;
    }

    /// @notice Aggregates a few calls to this contract into one multicall without modifying `msg.sender`.
    function multicall(Call[] calldata calls) external returns (Result[] memory callResults) {
        uint256 amount = calls.length;
        callResults = new Result[](amount);
        Call calldata call_;
        for (uint256 i = 0; i < amount;) {
            call_ = calls[i];
            Result memory result = callResults[i];
            // We perform a delegate call to ourselves here. Delegate call does not modify `msg.sender`, so
            // this will have the same effect as if `msg.sender` performed all the calls themselves one by one.
            // solhint-disable-next-line avoid-low-level-calls
            (result.success, result.returnData) = address(this).delegatecall(call_.callData);
            // solhint-disable-next-line no-inline-assembly
            assembly {
                // Revert if the call fails and failure is not allowed
                // `allowFailure := calldataload(call_)` and `success := mload(result)`
                if iszero(or(calldataload(call_), mload(result))) {
                    // Revert with `0x4d6a2328` (function selector for `MulticallFailed()`)
                    mstore(0x00, 0x4d6a232800000000000000000000000000000000000000000000000000000000)
                    revert(0x00, 0x04)
                }
            }
            unchecked {
                ++i;
            }
        }
    }
}