// SPDX-License-Identifier: MIT

/* solhint-disable var-name-mixedcase */

pragma solidity >=0.7.0 <0.9.0;
pragma experimental ABIEncoderV2;

import "../defaults/WitnetOracleTrustableDefault.sol";

// solhint-disable-next-line
interface OVM_GasPriceOracle {
    function getL1Fee(bytes calldata _data) external view returns (uint256);
}

/// @title Witnet Request Board "trustable" implementation contract.
/// @notice Contract to bridge requests to Witnet Decentralized Oracle Network.
/// @dev This contract enables posting requests that Witnet bridges will insert into the Witnet network.
/// The result of the requests will be posted back to this contract by the bridge nodes too.
/// @author The Witnet Foundation
contract WitnetOracleTrustableOvm2
    is 
        WitnetOracleTrustableDefault
{
    using WitnetV2 for WitnetV2.RadonSLA;

    function class() virtual override public view returns (string memory) {
        return type(WitnetOracleTrustableOvm2).name;
    }

    constructor(
            WitnetRequestFactory _factory,
            WitnetRequestBytecodes _registry,
            bool _upgradable,
            bytes32 _versionTag,
            uint256 _reportResultGasBase,
            uint256 _reportResultWithCallbackGasBase,
            uint256 _reportResultWithCallbackRevertGasBase,
            uint256 _sstoreFromZeroGas
        )
        WitnetOracleTrustableDefault(
            _factory,
            _registry,
            _upgradable,
            _versionTag,
            _reportResultGasBase,
            _reportResultWithCallbackGasBase,
            _reportResultWithCallbackRevertGasBase,
            _sstoreFromZeroGas
        )
    {
        __gasPriceOracleL1 = OVM_GasPriceOracle(0x420000000000000000000000000000000000000F);
    }

    OVM_GasPriceOracle immutable internal __gasPriceOracleL1;

    function _getCurrentL1Fee(uint16 _resultMaxSize) virtual internal view returns (uint256) {
        return __gasPriceOracleL1.getL1Fee(
            abi.encodePacked(
                hex"06eb2c42000000000000000000000000000000000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000020000000000000000000000000000000000000000000000000000000ffffffffff00000000000000000000000000000000000000000000000000000000fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff00000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000000000000000ff",
                _resultMaxBuffer(_resultMaxSize)
            )
        );
    }

    function _resultMaxBuffer(uint16 _resultMaxSize) private pure returns (bytes memory) {
        unchecked {
            uint256[] memory _buffer = new uint256[](_resultMaxSize / 32);
            for (uint _ix = 0; _ix < _buffer.length; _ix ++) {
                _buffer[_ix] = type(uint256).max;
            }
            return abi.encodePacked(
                _buffer,
                uint256((1 << (_resultMaxSize % 32)) - 1)
            );
        }
    }

    // ================================================================================================================
    // --- Overrides 'IWitnetOracle' ----------------------------------------------------------------------------

    /// @notice Estimate the minimum reward required for posting a data request.
    /// @dev Underestimates if the size of returned data is greater than `_resultMaxSize`. 
    /// @param _gasPrice Expected gas price to pay upon posting the data request.
    /// @param _resultMaxSize Maximum expected size of returned data (in bytes).
    function estimateBaseFee(uint256 _gasPrice, uint16 _resultMaxSize)
        public view 
        virtual override
        returns (uint256)
    {
        return _getCurrentL1Fee(_resultMaxSize) + WitnetOracleTrustableDefault.estimateBaseFee(_gasPrice, _resultMaxSize);
    }

    /// @notice Estimate the minimum reward required for posting a data request with a callback.
    /// @param _gasPrice Expected gas price to pay upon posting the data request.
    /// @param _callbackGasLimit Maximum gas to be spent when reporting the data request result.
    function estimateBaseFeeWithCallback(uint256 _gasPrice, uint24 _callbackGasLimit)
        public view
        virtual override
        returns (uint256)
    {
        return _getCurrentL1Fee(32) + WitnetOracleTrustableDefault.estimateBaseFeeWithCallback(_gasPrice, _callbackGasLimit);
    }

    // ================================================================================================================
    // --- Overrides 'IWitnetOracleReporter' --------------------------------------------------------------------------

    /// @notice Estimates the actual earnings (or loss), in WEI, that a reporter would get by reporting result to given query,
    /// @notice based on the gas price of the calling transaction. Data requesters should consider upgrading the reward on 
    /// @notice queries providing no actual earnings.
    function estimateReportEarnings(
            uint256[] calldata _witnetQueryIds, 
            bytes calldata _reportTxMsgData,
            uint256 _reportTxGasPrice, 
            uint256 _nanoWitPrice
        )
        external view
        virtual override
        returns (uint256 _revenues, uint256 _expenses)
    {
        for (uint _ix = 0; _ix < _witnetQueryIds.length; _ix ++) {
            if (WitnetOracleDataLib.seekQueryStatus(_witnetQueryIds[_ix]) == WitnetV2.QueryStatus.Posted) {
                WitnetV2.Request storage __request = WitnetOracleDataLib.seekQueryRequest(_witnetQueryIds[_ix]);
                if (__request.gasCallback > 0) {
                    _expenses += WitnetOracleTrustableDefault.estimateBaseFeeWithCallback(
                        _reportTxGasPrice, 
                        __request.gasCallback
                    );
                } else {
                    if (__request.witnetRAD != bytes32(0)) {
                        _expenses += WitnetOracleTrustableDefault.estimateBaseFee(
                            _reportTxGasPrice, 
                            registry.lookupRadonRequestResultMaxSize(__request.witnetRAD)
                        );
                    } else {
                        // todo: improve profit estimation accuracy if reporting on deleted query
                        _expenses += WitnetOracleTrustableDefault.estimateBaseFee(
                            _reportTxGasPrice, 
                            uint16(0)
                        ); 
                    }
                }
                _expenses += __request.witnetSLA.nanoWitTotalFee() * _nanoWitPrice;
                _revenues += __request.evmReward;
            }
        }
        _expenses += __gasPriceOracleL1.getL1Fee(_reportTxMsgData);
    }
}