// SPDX-License-Identifier: BUSL-1.1

pragma solidity ^0.8.0;

import "../data/Keys.sol";
import "../data/DataStore.sol";

abstract contract GlobalReentrancyGuard {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.
    uint256 private constant NOT_ENTERED = 0;
    uint256 private constant ENTERED = 1;

    DataStore public immutable dataStore;

    constructor(DataStore _dataStore) {
        dataStore = _dataStore;
    }

    modifier globalNonReentrant() {
        _globalNonReentrantBefore();
        _;
        _globalNonReentrantAfter();
    }

    function _globalNonReentrantBefore() private {
        uint256 status = dataStore.getUint(Keys.REENTRANCY_GUARD_STATUS);

        require(status == NOT_ENTERED, "ReentrancyGuard: reentrant call");

        dataStore.setUint(Keys.REENTRANCY_GUARD_STATUS, ENTERED);
    }

    function _globalNonReentrantAfter() private {
        dataStore.setUint(Keys.REENTRANCY_GUARD_STATUS, NOT_ENTERED);
    }
}