// File: @openzeppelin/contracts/access/Ownable.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

import "../utils/Context.sol";

/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor() {
        _setOwner(_msgSender());
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        _setOwner(address(0));
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        _setOwner(newOwner);
    }

    function _setOwner(address newOwner) private {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}

// File: @openzeppelin/contracts/utils/Context.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.0;

/**
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes calldata) {
        return msg.data;
    }
}

// File: /contracts/infrastructure/authentication/IAuthenticator.sol



// SPDX-License-Identifier: ISC
pragma solidity ^0.8.0 <0.9.0;


/// @title IAuthenticator
/// @dev Authenticator interface
/// @author Frank Bonnet - <frankbonnet@outlook.com>
interface IAuthenticator {
    

    /// @dev Authenticate 
    /// Returns whether `_account` is authenticated
    /// @param _account The account to authenticate
    /// @return whether `_account` is successfully authenticated
    function authenticate(address _account) external view returns (bool);
}
// File: /contracts/infrastructure/authentication/whitelist/IWhitelist.sol



// SPDX-License-Identifier: ISC
pragma solidity ^0.8.0 <0.9.0;

import "../IAuthenticator.sol";


/// @title IWhitelist 
/// @dev Whitelist authentication interface
/// @author Frank Bonnet - <frankbonnet@outlook.com>
interface IWhitelist is IAuthenticator {
    

    /// @dev Add `_accounts` to the whitelist
    /// @param _accounts The accounts to add
    function add(address[] calldata _accounts) external;


    /// @dev Remove `_accounts` from the whitelist
    /// @param _accounts The accounts to remove
    function remove(address[] calldata _accounts) external;
}
// File: /contracts/infrastructure/authentication/whitelist/Whitelist.sol



// SPDX-License-Identifier: ISC
pragma solidity ^0.8.0 <0.9.0;

import "@openzeppelin/contracts/access/Ownable.sol";

import "./IWhitelist.sol";


/// @title Whitelist 
/// @dev Whitelist authentication
/// @author Frank Bonnet - <frankbonnet@outlook.com>
contract Whitelist is Ownable, IWhitelist {
    

    /// Whitelist
    mapping (address => bool) internal list;


    /// @dev Add `_accounts` to the whitelist
    /// @param _accounts The accounts to add
    function add(address[] calldata _accounts) override public onlyOwner {
        for (uint i = 0; i < _accounts.length; i++) {
            list[_accounts[i]] = true;
        }
    }


    /// @dev Remove `_accounts` from the whitelist
    /// @param _accounts The accounts to remove
    function remove(address[] calldata _accounts) override public onlyOwner {
       for (uint i = 0; i < _accounts.length; i++) {
            list[_accounts[i]] = false;
        }
    }

    /// @dev Authenticate 
    /// Returns whether `_account` is on the whitelist
    /// @param _account The account to authenticate
    /// @return whether `_account` is successfully authenticated
    function authenticate(address _account) override public view returns (bool) {
        return list[_account];
    }
}