// SPDX-License-Identifier: MIT

pragma solidity >=0.8.0 <0.9.0;

import "../base/WitOracleBaseQueriableTrustable.sol";

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

/// @title Queriable WitOracle "trustable" implementation contract for OVM2 chains. 
/// @author The Witnet Foundation
contract WitOracleTrustableOvm2
    is 
        WitOracleBaseQueriableTrustable
{
    function class() virtual override public view returns (string memory) {
        return type(WitOracleTrustableOvm2).name;
    }

    constructor(
            EvmImmutables memory _immutables,
            WitOracleRadonRegistry _registry,
            bytes32 _versionTag
        )
        WitOracleBaseQueriable(
            _immutables,
            _registry
        )
        WitOracleBaseQueriableTrustable(_versionTag)
    {
        __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 'IWitOracle' -------------------------------------------------------------------------------------

    /// @notice Estimate the minimum reward required for posting a data request.
    /// @param _evmGasPrice Expected gas price to pay upon posting the data request.
    function estimateBaseFee(uint256 _evmGasPrice)
        public view
        virtual override
        returns (uint256)
    {
        return _getCurrentL1Fee(32) + WitOracleBaseQueriable.estimateBaseFee(_evmGasPrice);
    }

    /// @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 _callbackGas Maximum gas to be spent when reporting the data request result.
    function estimateBaseFeeWithCallback(uint256 _gasPrice, uint24 _callbackGas)
        public view
        virtual override
        returns (uint256)
    {
        return _getCurrentL1Fee(32) + WitOracleBaseQueriable.estimateBaseFeeWithCallback(_gasPrice, _callbackGas);
    }

    /// @notice Estimate the extra reward (i.e. over the base fee) to be paid when posting a new
    /// @notice data query in order to avoid getting provable "too low incentives" results from
    /// @notice the Wit/Oracle blockchain. 
    /// @dev The extra fee gets calculated in proportion to:
    /// @param _evmGasPrice Tentative EVM gas price at the moment the query result is ready.
    /// @param _evmWitPrice Tentative nanoWit price in Wei at the moment the query is solved on the Wit/Oracle blockchain.
    /// @param _querySLA The query SLA data security parameters as required for the Wit/Oracle blockchain. 
    function estimateExtraFee(
            uint256 _evmGasPrice, 
            uint256 _evmWitPrice, 
            Witnet.QuerySLA memory _querySLA
        )
        public view
        virtual override
        returns (uint256)
    {
        return (
            _getCurrentL1Fee(_querySLA.witResultMaxSize)
                + WitOracleBaseQueriable.estimateExtraFee(
                    _evmGasPrice,
                    _evmWitPrice,
                    _querySLA
                )
        );
    }


    // ================================================================================================================
    // --- Overrides 'IWitOracleLegacy' -------------------------------------------------------------------------------

    /// @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) + WitOracleBaseQueriableTrustable.estimateBaseFee(_gasPrice, _resultMaxSize);
    }


    // ================================================================================================================
    // --- Overrides 'IWitOracleQueriableTrustableReporter' --------------------------------------------------------------------------

    /// @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 _queryIds, 
            bytes calldata _evmMsgData,
            uint256 _evmGasPrice, 
            uint256 _evmWitPrice
        )
        external view
        virtual override
        returns (uint256 _revenues, uint256 _expenses)
    {
        for (uint _ix = 0; _ix < _queryIds.length; _ix ++) {
            uint256 _queryId = _queryIds[_ix];
            if (
                getQueryStatus(_queryId) == Witnet.QueryStatus.Posted
            ) {
                WitOracleDataLib.Query storage __query = WitOracleDataLib.seekQuery(_queryId);
                if (__query.request.callbackGas > 0) {
                    _expenses += (
                        WitOracleBaseQueriable.estimateBaseFeeWithCallback(_evmGasPrice, __query.request.callbackGas)
                            + WitOracleBaseQueriable.estimateExtraFee(
                                _evmGasPrice, _evmWitPrice,
                                Witnet.QuerySLA({
                                    witResultMaxSize: uint16(0),
                                    witCommitteeSize: __query.slaParams.witCommitteeSize,
                                    witUnitaryReward: __query.slaParams.witUnitaryReward
                                })
                            )
                    );
                } else {
                    _expenses += (
                        WitOracleBaseQueriable.estimateBaseFee(_evmGasPrice)
                            + WitOracleBaseQueriable.estimateExtraFee(
                                _evmGasPrice, _evmWitPrice,
                                __query.slaParams
                            )
                    );
                }
                _expenses += __query.slaParams.witUnitaryReward * _evmWitPrice;
                _revenues += Witnet.QueryEvmReward.unwrap(__query.reward);
            }
        }
        _expenses += __gasPriceOracleL1.getL1Fee(_evmMsgData);
    }
}