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/**
 *     NOTICE
 *
 *     The T-REX software is licensed under a proprietary license or the GPL v.3.
 *     If you choose to receive it under the GPL v.3 license, the following applies:
 *     T-REX is a suite of smart contracts implementing the ERC-3643 standard and
 *     developed by Tokeny to manage and transfer financial assets on EVM blockchains
 *
 *     Copyright (C) 2023, Tokeny sàrl.
 *
 *     This program is free software: you can redistribute it and/or modify
 *     it under the terms of the GNU General Public License as published by
 *     the Free Software Foundation, either version 3 of the License, or
 *     (at your option) any later version.
 *
 *     This program is distributed in the hope that it will be useful,
 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *     GNU General Public License for more details.
 *
 *     You should have received a copy of the GNU General Public License
 *     along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

pragma solidity 0.8.17;

import "@openzeppelin/contracts/access/Ownable.sol";

import "./Roles.sol";

contract AgentRole is Ownable {
    using Roles for Roles.Role;

    Roles.Role private _agents;

    event AgentAdded(address indexed _agent);
    event AgentRemoved(address indexed _agent);

    modifier onlyAgent() {
        require(isAgent(msg.sender), "AgentRole: caller does not have the Agent role");
        _;
    }

    function addAgent(address _agent) public onlyOwner {
        require(_agent != address(0), "invalid argument - zero address");
        _agents.add(_agent);
        emit AgentAdded(_agent);
    }

    function removeAgent(address _agent) public onlyOwner {
        require(_agent != address(0), "invalid argument - zero address");
        _agents.remove(_agent);
        emit AgentRemoved(_agent);
    }

    function isAgent(address _agent) public view returns (bool) {
        return _agents.has(_agent);
    }
}