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HotelRoom.sol

pragma solidity ^0.6.0;

contract HotelRoom {
     
    enum Statuses { Vacant, Occupied }
    Statuses currentStatus;
    
    event Occupy(address _occupant, uint _amount);
    
    address payable public owner;
    
    constructor() public {
        owner = msg.sender;
        currentStatus = Statuses.Vacant;
    }
    
    modifier onlyWhileVacant {
        require(currentStatus == Statuses.Vacant, "Currently occupied");
        _;
    }
    
    modifier costs(uint _amount) {
        require(msg.value >= _amount, "Not enough Ether provided");
        _;
    }
    
    receive() external payable onlyWhileVacant costs(2 ether) {
        //require(msg.value >= 2 ether, "Not enough Ether provided");
        currentStatus = Statuses.Occupied;
        owner.transfer(msg.value);
        emit Occupy(msg.sender, msg.value);
    }
}