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@@ -1,174 +0,0 @@
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-pragma solidity ^0.6.0;
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-
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-import "../token/ERC20/SafeERC20.sol";
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-import "../access/Ownable.sol";
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-import "../math/SafeMath.sol";
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-
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-/**
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- * @title TokenVesting
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- * @dev A token holder contract that can release its token balance gradually like a
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- * typical vesting scheme, with a cliff and vesting period. Optionally revocable by the
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- * owner.
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- */
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-contract TokenVesting is Ownable {
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- // The vesting schedule is time-based (i.e. using block timestamps as opposed to e.g. block numbers), and is
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- // therefore sensitive to timestamp manipulation (which is something miners can do, to a certain degree). Therefore,
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- // it is recommended to avoid using short time durations (less than a minute). Typical vesting schemes, with a
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- // cliff period of a year and a duration of four years, are safe to use.
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- // solhint-disable not-rely-on-time
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-
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- using SafeMath for uint256;
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- using SafeERC20 for IERC20;
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-
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- event TokensReleased(address token, uint256 amount);
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- event TokenVestingRevoked(address token);
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-
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- // beneficiary of tokens after they are released
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- address private _beneficiary;
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-
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- // Durations and timestamps are expressed in UNIX time, the same units as block.timestamp.
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- uint256 private _cliff;
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- uint256 private _start;
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- uint256 private _duration;
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-
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- bool private _revocable;
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-
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- mapping (address => uint256) private _released;
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- mapping (address => bool) private _revoked;
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-
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- /**
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- * @dev Creates a vesting contract that vests its balance of any ERC20 token to the
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- * beneficiary, gradually in a linear fashion until start + duration. By then all
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- * of the balance will have vested.
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- * @param beneficiary address of the beneficiary to whom vested tokens are transferred
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- * @param cliffDuration duration in seconds of the cliff in which tokens will begin to vest
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- * @param start the time (as Unix time) at which point vesting starts
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- * @param duration duration in seconds of the period in which the tokens will vest
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- * @param revocable whether the vesting is revocable or not
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- */
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- constructor (address beneficiary, uint256 start, uint256 cliffDuration, uint256 duration, bool revocable) public {
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- require(beneficiary != address(0), "TokenVesting: beneficiary is the zero address");
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- // solhint-disable-next-line max-line-length
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- require(cliffDuration <= duration, "TokenVesting: cliff is longer than duration");
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- require(duration > 0, "TokenVesting: duration is 0");
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- // solhint-disable-next-line max-line-length
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- require(start.add(duration) > block.timestamp, "TokenVesting: final time is before current time");
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-
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- _beneficiary = beneficiary;
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- _revocable = revocable;
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- _duration = duration;
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- _cliff = start.add(cliffDuration);
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- _start = start;
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- }
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-
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- /**
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- * @return the beneficiary of the tokens.
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- */
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- function beneficiary() public view returns (address) {
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- return _beneficiary;
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- }
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-
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- /**
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- * @return the cliff time of the token vesting.
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- */
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- function cliff() public view returns (uint256) {
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- return _cliff;
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- }
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-
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- /**
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- * @return the start time of the token vesting.
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- */
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- function start() public view returns (uint256) {
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- return _start;
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- }
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-
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- /**
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- * @return the duration of the token vesting.
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- */
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- function duration() public view returns (uint256) {
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- return _duration;
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- }
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-
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- /**
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- * @return true if the vesting is revocable.
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- */
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- function revocable() public view returns (bool) {
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- return _revocable;
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- }
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-
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- /**
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- * @return the amount of the token released.
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- */
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- function released(address token) public view returns (uint256) {
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- return _released[token];
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- }
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-
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- /**
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- * @return true if the token is revoked.
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- */
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- function revoked(address token) public view returns (bool) {
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- return _revoked[token];
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- }
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-
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- /**
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- * @notice Transfers vested tokens to beneficiary.
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- * @param token ERC20 token which is being vested
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- */
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- function release(IERC20 token) public {
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- uint256 unreleased = _releasableAmount(token);
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-
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- require(unreleased > 0, "TokenVesting: no tokens are due");
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-
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- _released[address(token)] = _released[address(token)].add(unreleased);
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-
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- token.safeTransfer(_beneficiary, unreleased);
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-
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- emit TokensReleased(address(token), unreleased);
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- }
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-
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- /**
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- * @notice Allows the owner to revoke the vesting. Tokens already vested
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- * remain in the contract, the rest are returned to the owner.
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- * @param token ERC20 token which is being vested
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- */
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- function revoke(IERC20 token) public onlyOwner {
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- require(_revocable, "TokenVesting: cannot revoke");
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- require(!_revoked[address(token)], "TokenVesting: token already revoked");
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-
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- uint256 balance = token.balanceOf(address(this));
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-
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- uint256 unreleased = _releasableAmount(token);
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- uint256 refund = balance.sub(unreleased);
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-
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- _revoked[address(token)] = true;
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-
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- token.safeTransfer(owner(), refund);
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-
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- emit TokenVestingRevoked(address(token));
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- }
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-
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- /**
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- * @dev Calculates the amount that has already vested but hasn't been released yet.
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- * @param token ERC20 token which is being vested
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- */
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- function _releasableAmount(IERC20 token) private view returns (uint256) {
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- return _vestedAmount(token).sub(_released[address(token)]);
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- }
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-
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- /**
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- * @dev Calculates the amount that has already vested.
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- * @param token ERC20 token which is being vested
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- */
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- function _vestedAmount(IERC20 token) private view returns (uint256) {
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- uint256 currentBalance = token.balanceOf(address(this));
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- uint256 totalBalance = currentBalance.add(_released[address(token)]);
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-
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- if (block.timestamp < _cliff) {
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- return 0;
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- } else if (block.timestamp >= _start.add(_duration) || _revoked[address(token)]) {
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- return totalBalance;
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- } else {
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- return totalBalance.mul(block.timestamp.sub(_start)).div(_duration);
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- }
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- }
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-}
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