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//SPDX-License-Identifier: Unlicense
pragma solidity ^0.8.0;

contract DepositLock {

enum Stages {
    AcceptingDeposits,
    FreezingDeposits,
    ReleasingDeposits
  }

Stages public stage = Stages.AcceptingDeposits;

uint public creationTime = block.timestamp;

mapping (address => uint) public balances;    
  
  modifier atStage(Stages _stage) {
    require(stage == _stage, "Action not allowed Now");
    _;
  }

modifier timedTransitions() {
    if (stage == Stages.AcceptingDeposits && block.timestamp >= creationTime + 1 days)
      nextStage();
    if (stage == Stages.FreezingDeposits && block.timestamp >= creationTime + 8 days)
      nextStage();
    _;
  }
    
  function nextStage() internal {
    stage = Stages(uint(stage) + 1);
  }

function deposit() public payable timedTransitions atStage(Stages.AcceptingDeposits) {
    balances[msg.sender] += msg.value; 
  }
  
  function withdraw() public timedTransitions atStage(Stages.ReleasingDeposits) { 
    uint amount = balances[msg.sender];
    balances[msg.sender] = 0;
    payable(msg.sender).transfer(amount);
  }
}