axionEthBank.sol

// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.4.0 <0.5.0;

/* Developed By Salman Haider
   Date: 20 May 2021
*/
// interface Aion
contract Aion {
    uint256 public serviceFee;
    function ScheduleCall(uint256 blocknumber, address to, uint256 value, uint256 gaslimit, uint256 gasprice, bytes data, bool schedType) public payable returns (uint,address);

}

contract EtherBank {
    Aion aion;
    address public owner;
    address public user;
    address[] public depositers;
    
    mapping(address => uint) public depositedBalance;
    mapping(address => bool) public hasDeposited;

    event etherDeposited(address depositer, uint ethAmount);
    event etherReturned(address depositer, uint ethAmount);

    constructor() public {
        owner = msg.sender;
    }
    // modifier onlyOwner {
    //     require(msg.sender == owner);
    //     _;
    // }
    
    function schedule_rqsr() public {
        aion = Aion(0xFcFB45679539667f7ed55FA59A15c8Cad73d9a4E);
        bytes memory data = abi.encodeWithSelector(bytes4(keccak256('returnEth()')));
        uint callCost = 200000*1e9 + aion.serviceFee();
        aion.ScheduleCall.value(callCost)( block.number+10, address(this), 0, 200000, 1e9, data, false);
    }


    function () public payable {}

/* 
    1. Anyone can depositEther to the EtherBank 
    2. DepositEther() function will deposit the Ether from user address 
    3. DepositEther() will save the balance and address of the depositers
*/

    function depositEther() public payable {
        user = msg.sender;
        uint amount = msg.value;
           
            depositers.push(user);
            // Eth is deposited to the contract 
            depositedBalance[user] += amount;
            hasDeposited[user] = true; 
            emit etherDeposited(user, amount);
    }
    
/*
    1. OnlyOwner can call returnEth() in order to return ethers to all the addresses
    2. returnEth() should be automated and can only be called from inside the contract
    3. If the etherBank Contract is deployed on rinkeby at Block : 0 
       Then 
       after 10 blocks are mined  ( 0 + 10 ) on the rinkeby testnet 
          => An automated scheduler should call the returnEth() function 
                from inside the deployed EtherBank smartContract
          => To return ethers deposited by the depositers
*/
    
    
    
    function returnEth() public {
        
        for (uint i=0; i<depositers.length; i++) {
            user = depositers[i];
            uint refundedAmount = depositedBalance[user];
            
            user.transfer(refundedAmount);
            depositedBalance[user] = 0;
            hasDeposited[user] = false;
            emit etherReturned(user, refundedAmount);
        }
    }                
}