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LockedNORI.sol
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LockedNORI.sol
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// SPDX-License-Identifier: MIT
pragma solidity =0.8.17;
import "@openzeppelin/contracts-upgradeable/utils/math/MathUpgradeable.sol";
import "./BridgedPolygonNORI.sol";
import "./deprecated/ERC777PresetPausablePermissioned.sol";
import {LockedNORILib, Schedule, Cliff} from "./LockedNORILib.sol";
/**
* @title A wrapped BridgedPolygonNORI token contract for vesting and lockup.
* @author Nori Inc.
* @notice Based on the mechanics of a wrapped ERC-20 token, this contract layers schedules over the withdrawal
* functionality to implement _vesting_ (a revocable grant) and _lockup_ (an irrevocable time-lock on utility).
*
* ##### Additional behaviors and features:
*
* ###### Grants
*
* - _Grants_ define lockup periods and vesting schedules for tokens.
* - A single grant per address is supported.
*
* ###### Vesting
*
* - _Vesting_ is applied in scenarios where the tokens may need to be recaptured by Nori. This could either be due to
* an employee leaving the company before being fully vested or because one of our suppliers incurs a carbon loss so
* their restricted (unvested in the terminology of this contract). Tokens need to be recaptured to mitigate the loss
* and make the original buyer whole by using them to purchases new NRTs on their behalf.
* - Tokens are released linearly from the latest cliff date to the end date of the grant based on the `block.timestamp`
* of each block.
*
* ###### Lockup
*
* - _Lockup_ refers to tokens that are guaranteed to be available to the grantee but are subject to a time delay before
* they are usable / transferrable out of this smart contract. This is a standard mechanism used to avoid sudden floods
* of liquidity in the BridgedPolygonNORI token that could severely depress the price.
* - Unlock is always at the same time or lagging vesting
* - Transfer of LockedNORI under lockup is forbidden
*
* ###### Cliffs
*
* - A _cliff_ refers to a period prior to which no tokens are vested or unlocked. Cliffs are defined by a date and an
* amount which must be <= the overall grant amount.
* - This contract supports a maximum of two distinct cliffs per grant. The effect of fewer cliffs can be achieved by
* setting one of both cliff times to the start time or end time, and/or by setting the cliff amount to zero.
*
* ###### Additional behaviors and features:
*
* - [Upgradeable](https://docs.openzeppelin.com/contracts/4.x/upgradeable)
* - [Initializable](https://docs.openzeppelin.com/contracts/4.x/upgradeable#multiple-inheritance)
* - [Pausable](https://docs.openzeppelin.com/contracts/4.x/api/security#Pausable): all functions that mutate state are
* pausable
* - [Role-based access control](https://docs.openzeppelin.com/contracts/4.x/access-control)
* - `TOKEN_GRANTER_ROLE`: Can create token grants without sending BridgedPolygonNORI to the contract `createGrant`
* - `PAUSER_ROLE`: Can pause and unpause the contract
* - `DEFAULT_ADMIN_ROLE`: This is the only role that can add/revoke other accounts to any of the roles
* - [Can receive BridgedPolygonNORI ERC-777 tokens](https://eips.ethereum.org/EIPS/eip-777#hooks):
* BridgedPolygonNORI is wrapped and grants are created upon receipt
* - [Limited ERC-777 functionality](https://eips.ethereum.org/EIPS/eip-777): The `burn` and `operatorBurn` will revert
* as only the internal variants are expected to be used. Additionally, `mint` is not callable as only the internal
* variants are expected to be used when wrapping BridgedPolygonNORI
* - [Limited ERC-20 functionality](https://docs.openzeppelin.com/contracts/4.x/erc20): `mint` is not callable as only
* the internal variants are expected to be used when wrapping BridgedPolygonNORI. Additionally, `burn` functions are
* not externally callable
* - [Extended Wrapped ERC-20 functionality](https://docs.openzeppelin.com/contracts/4.x/api/token/erc20#ERC20Wrapper):
* In absence of a grant `LockedNORI functions` identically to a standard wrapped token. Additionally, when a grant is
* defined, LockedNORI follows the restrictions noted above.
*
* ##### Inherits:
*
* - [ERC777Upgradeable](https://docs.openzeppelin.com/contracts/4.x/api/token/erc777#ERC777)
* - [PausableUpgradeable](https://docs.openzeppelin.com/contracts/4.x/api/security#Pausable)
* - [AccessControlEnumerableUpgradeable](https://docs.openzeppelin.com/contracts/4.x/api/access)
* - [ContextUpgradeable](https://docs.openzeppelin.com/upgrades-plugins/1.x/writing-upgradeable)
* - [Initializable](https://docs.openzeppelin.com/contracts/4.x/api/proxy#Initializable)
* - [ERC165Upgradeable](https://docs.openzeppelin.com/contracts/4.x/api/utils#ERC165)
*
* ##### Implements:
*
* - [IERC777Upgradeable](https://docs.openzeppelin.com/contracts/4.x/api/token/erc777#IERC777)
* - [IERC20Upgradeable](https://docs.openzeppelin.com/contracts/4.x/api/token/erc20#IERC20)
* - [IAccessControlEnumerable](https://docs.openzeppelin.com/contracts/4.x/api/access#AccessControlEnumerable)
* - [IERC165Upgradeable](https://docs.openzeppelin.com/contracts/4.x/api/utils#IERC165)
*
* ##### Uses:
*
* - [LockedNORILib](./LockedNORILib.md) for `Schedule`
* - [MathUpgradeable](https://docs.openzeppelin.com/contracts/4.x/api/utils#Math)
*/
contract LockedNORI is ERC777PresetPausablePermissioned {
using LockedNORILib for Schedule;
struct TokenGrant {
Schedule vestingSchedule;
Schedule lockupSchedule;
uint256 grantAmount;
uint256 claimedAmount;
uint256 originalAmount;
bool exists;
uint256 lastRevocationTime;
uint256 lastQuantityRevoked;
}
struct TokenGrantDetail {
uint256 grantAmount;
address recipient;
uint256 startTime;
uint256 vestEndTime;
uint256 unlockEndTime;
uint256 cliff1Time;
uint256 cliff2Time;
uint256 vestCliff1Amount;
uint256 vestCliff2Amount;
uint256 unlockCliff1Amount;
uint256 unlockCliff2Amount;
uint256 claimedAmount;
uint256 originalAmount;
uint256 lastRevocationTime;
uint256 lastQuantityRevoked;
bool exists;
}
struct CreateTokenGrantParams {
address recipient;
uint256 startTime;
uint256 vestEndTime;
uint256 unlockEndTime;
uint256 cliff1Time;
uint256 cliff2Time;
uint256 vestCliff1Amount;
uint256 vestCliff2Amount;
uint256 unlockCliff1Amount;
uint256 unlockCliff2Amount;
}
struct DepositForParams {
address recipient;
uint256 startTime;
}
/**
* @notice Role conferring creation and revocation of token grants.
*/
bytes32 public constant TOKEN_GRANTER_ROLE = keccak256("TOKEN_GRANTER_ROLE");
/**
* @notice Used to register the ERC777TokensRecipient recipient interface in the
* ERC-1820 registry. No longer used, retained to maintain storage layout.
*/
bytes32 public constant ERC777_TOKENS_RECIPIENT_HASH =
keccak256("ERC777TokensRecipient");
/**
* @notice A mapping from grantee to grant
*/
mapping(address => TokenGrant) private _grants;
/**
* @notice The BridgedPolygonNORI contract that this contract wraps tokens for
*/
BridgedPolygonNORI private _bridgedPolygonNori;
/**
* @notice The [ERC-1820](https://eips.ethereum.org/EIPS/eip-1820) pseudo-introspection registry
* contract
*/
IERC1820RegistryUpgradeable private _erc1820;
/**
* @notice Emitted on successful batch creation of new grants.
*/
event TokenGrantCreatedBatch(uint256 totalAmount);
/**
* @notice Emitted on successful creation of a new grant.
*/
event TokenGrantCreated(
address indexed recipient,
uint256 indexed amount,
uint256 indexed startTime,
uint256 vestEndTime,
uint256 unlockEndTime
);
/**
* @notice Emitted on when the vesting portion of an active grant is terminated.
*/
event UnvestedTokensRevoked(
uint256 indexed atTime,
address indexed from,
uint256 indexed quantity
);
/**
* @notice Emitted on withdrawl of fully unlocked tokens.
*/
event TokensClaimed(
address indexed from,
address indexed to,
uint256 quantity
);
/**
* @notice Emitted when the underlying token contract address is updated due to migration.
*/
event UnderlyingTokenAddressUpdated(address from, address to);
/**
* @notice Locks the contract, preventing any future re-initialization.
* @dev See more [here](https://docs.openzeppelin.com/contracts/4.x/api/proxy#Initializable-_disableInitializers--).
* @custom:oz-upgrades-unsafe-allow constructor
*/
constructor() {
_disableInitializers();
}
/**
* @notice Mints wrapper token to `recipient` if a grant exists.
*
* @dev If `startTime` is zero no grant is set up. Satisfies situations where funding of the grant happens over time.
*
* @param amount The quantity of bpNORI to deposit.
*/
function depositFor(address recipient, uint256 amount)
external
whenNotPaused
returns (bool)
{
require(_grants[recipient].exists, "lNORI: Cannot deposit without a grant");
if (_bridgedPolygonNori.transferFrom(_msgSender(), address(this), amount)) {
super._mint(recipient, amount, "", "");
return true;
}
revert("lNORI: transferFrom underlying asset failed");
}
/**
* @notice Claim unlocked tokens and withdraw them to the `to` address.
*
* @dev This function burns `amount` of LockedNORI and transfers `amount`
* of BridgedPolygonNORI from the LockedNORI contract's balance to
* `_msgSender()`'s balance.
*
* Enforcement of the availability of wrapped and unlocked tokens
* for the `_burn` call happens in `_beforeTokenTransfer`
*
* ##### Requirements:
*
* - Can only be used when the contract is not paused.
*/
function withdrawTo(address recipient, uint256 amount)
external
whenNotPaused
returns (bool)
{
TokenGrant storage grant = _grants[_msgSender()];
super._burn(_msgSender(), amount, "", "");
grant.claimedAmount += amount;
if (_bridgedPolygonNori.transfer(recipient, amount)) {
emit TokensClaimed(_msgSender(), recipient, amount);
return true;
}
revert("lNORI: Transfer to underlying asset failed");
}
/**
* @notice Batch version of `createGrant` with permit support.
*/
function batchCreateGrants(
uint256[] calldata amounts,
bytes[] calldata grantParams,
uint256 deadline,
uint8 v,
bytes32 r,
bytes32 s
) external whenNotPaused onlyRole(TOKEN_GRANTER_ROLE) {
require(
amounts.length == grantParams.length,
"lNORI: Requires one amount per grant detail"
);
uint256 totalAmount = 0;
for (uint8 i = 0; i < amounts.length; i++) {
totalAmount = totalAmount + amounts[i];
address recipient = _createGrant(amounts[i], grantParams[i]);
super._mint(recipient, amounts[i], "", "");
}
emit TokenGrantCreatedBatch(totalAmount);
_bridgedPolygonNori.permit(
_msgSender(),
address(this),
totalAmount,
deadline,
v,
r,
s
);
_bridgedPolygonNori.transferFrom(_msgSender(), address(this), totalAmount);
}
/**
* @notice Sets up a vesting + lockup schedule for recipient.
*
* @dev This function can be used as an alternative way to set up a grant that doesn't require
* wrapping BridgedPolygonNORI first.
*
* ##### Requirements:
*
* - Can only be used when the contract is not paused.
* - Can only be used when the caller has the `TOKEN_GRANTER_ROLE` role.
*/
function createGrant(
uint256 amount,
address recipient,
uint256 startTime,
uint256 vestEndTime,
uint256 unlockEndTime,
uint256 cliff1Time,
uint256 cliff2Time,
uint256 vestCliff1Amount,
uint256 vestCliff2Amount,
uint256 unlockCliff1Amount,
uint256 unlockCliff2Amount
) external whenNotPaused onlyRole(TOKEN_GRANTER_ROLE) {
bytes memory userData = abi.encode(
recipient,
startTime,
vestEndTime,
unlockEndTime,
cliff1Time,
cliff2Time,
vestCliff1Amount,
vestCliff2Amount,
unlockCliff1Amount,
unlockCliff2Amount
);
_createGrant(amount, userData);
}
/**
* @notice Truncates a batch of vesting grants of amounts in a single go
*
* @dev Transfers any unvested tokens in `fromAccounts`'s grant to `to` and reduces the total grant size. No change
* is made to balances that have vested but not yet been claimed whether locked or not.
*
* The behavior of this function can be used in two specific ways:
* - To revoke all remaining revokable tokens in a batch (regardless of time), set amount to 0 in the `amounts` array.
* - To revoke tokens at the current block timestamp, set `atTimes` to 0 in the `amounts` array.
*
* ##### Requirements:
*
* - Can only be used when the caller has the `TOKEN_GRANTER_ROLE` role.
* - The requirements of `_beforeTokenTransfer` apply to this function.
* - `fromAccounts.length == toAccounts.length == atTimes.length == amounts.length`.
*/
function batchRevokeUnvestedTokenAmounts(
address[] calldata fromAccounts,
address[] calldata toAccounts,
uint256[] calldata atTimes,
uint256[] calldata amounts
) external whenNotPaused onlyRole(TOKEN_GRANTER_ROLE) {
require(
fromAccounts.length == toAccounts.length,
"lNORI: fromAccounts and toAccounts length mismatch"
);
require(
toAccounts.length == atTimes.length,
"lNORI: toAccounts and atTimes length mismatch"
);
require(
atTimes.length == amounts.length,
"lNORI: atTimes and amounts length mismatch"
);
for (uint256 i = 0; i < fromAccounts.length; i++) {
_revokeUnvestedTokens(
fromAccounts[i],
toAccounts[i],
atTimes[i],
amounts[i]
);
}
}
/**
* @notice Number of unvested tokens that were revoked if any.
*/
function quantityRevokedFrom(address account)
external
view
returns (uint256)
{
TokenGrant storage grant = _grants[account];
return grant.originalAmount - grant.grantAmount;
}
/**
* @notice Vested balance less any claimed amount at current block timestamp.
*/
function vestedBalanceOf(address account) external view returns (uint256) {
return _vestedBalanceOf(account, block.timestamp); // solhint-disable-line not-rely-on-time, this is time-dependent
}
/**
* @notice Returns all governing settings for multiple grants
*
* @dev If a grant does not exist for an account, the resulting grant will be zeroed out in the return value
*/
function batchGetGrant(address[] calldata accounts)
public
view
returns (TokenGrantDetail[] memory)
{
TokenGrantDetail[] memory grantDetails = new TokenGrantDetail[](
accounts.length
);
for (uint256 i = 0; i < accounts.length; i++) {
grantDetails[i] = getGrant(accounts[i]);
}
return grantDetails;
}
/**
* @notice Returns all governing settings for a grant.
*/
function getGrant(address account)
public
view
returns (TokenGrantDetail memory)
{
TokenGrant storage grant = _grants[account];
return
TokenGrantDetail(
grant.grantAmount,
account,
grant.lockupSchedule.startTime,
grant.vestingSchedule.endTime,
grant.lockupSchedule.endTime,
grant.lockupSchedule.cliffs[0].time,
grant.lockupSchedule.cliffs[1].time,
grant.vestingSchedule.cliffs[0].amount,
grant.vestingSchedule.cliffs[1].amount,
grant.lockupSchedule.cliffs[0].amount,
grant.lockupSchedule.cliffs[1].amount,
grant.claimedAmount,
grant.originalAmount,
grant.lastRevocationTime,
grant.lastQuantityRevoked,
grant.exists
);
}
function initialize(BridgedPolygonNORI bridgedPolygonNoriAddress)
public
initializer
{
address[] memory operators = new address[](1);
operators[0] = _msgSender();
__Context_init_unchained();
__ERC165_init_unchained();
__AccessControl_init_unchained();
__AccessControlEnumerable_init_unchained();
__Pausable_init_unchained();
__ERC777PresetPausablePermissioned_init_unchained();
__ERC777_init_unchained("Locked NORI", "lNORI", operators);
_bridgedPolygonNori = bridgedPolygonNoriAddress;
_grantRole(TOKEN_GRANTER_ROLE, _msgSender());
}
/**
* @notice Admin function to update the underlying token contract address.
*
* @dev Used in case of major migrations only.
*/
function updateUnderlying(BridgedPolygonNORI newUnderlying)
external
whenNotPaused
onlyRole(DEFAULT_ADMIN_ROLE)
{
address old = address(_bridgedPolygonNori);
require(
old != address(newUnderlying),
"lNORI: updating underlying address to existing address"
);
_bridgedPolygonNori = newUnderlying;
emit UnderlyingTokenAddressUpdated(old, address(newUnderlying));
}
/**
* @notice Overridden standard ERC777.burn that will always revert
*
* @dev This function is not currently supported from external callers, so we override it so that we can revert.
*/
function burn(uint256, bytes memory) public pure override {
revert("lNORI: burning not supported");
}
/**
* @notice Overridden standard ERC777.operatorBurn that will always revert
*
* @dev This function is not currently supported from external callers so we override it so that we can revert.
*/
function operatorBurn(
address,
uint256,
bytes memory,
bytes memory
) public pure override {
revert("lNORI: burning not supported");
}
/**
* @notice Unlocked balance less any claimed amount at current block timestamp.
*/
function unlockedBalanceOf(address account) public view returns (uint256) {
return _unlockedBalanceOf(account, block.timestamp);
}
/**
* @notice Sets up a vesting + lockup schedule for recipient (implementation).
*
* @dev All grants must include a lockup schedule and can optionally *also*
* include a vesting schedule. Tokens are withdrawable once they are
* vested *and* unlocked.
*
* It is also callable externally (see `grantTo`) to handle cases
* where tokens are incrementally deposited after the grant is established.
*/
function _createGrant(uint256 amount, bytes memory userData)
internal
returns (address recipient)
{
CreateTokenGrantParams memory params = abi.decode(
userData,
(CreateTokenGrantParams)
);
require(
address(params.recipient) != address(0),
"lNORI: Recipient cannot be zero address"
);
require(
!hasRole(TOKEN_GRANTER_ROLE, params.recipient),
"lNORI: Recipient cannot be grant admin"
);
require(
params.startTime < params.unlockEndTime,
"lNORI: unlockEndTime cannot be before startTime"
);
require(
block.timestamp < params.unlockEndTime,
"lNORI: unlockEndTime cannot be in the past"
);
require(!_grants[params.recipient].exists, "lNORI: Grant already exists");
TokenGrant storage grant = _grants[params.recipient];
grant.grantAmount = amount;
grant.originalAmount = amount;
grant.exists = true;
if (params.vestEndTime > params.startTime) {
require(
params.vestCliff1Amount >= params.unlockCliff1Amount ||
params.vestCliff2Amount >= params.unlockCliff2Amount,
"lNORI: unlock cliff > vest cliff"
);
grant.vestingSchedule.totalAmount = amount;
grant.vestingSchedule.startTime = params.startTime;
grant.vestingSchedule.endTime = params.vestEndTime;
grant.vestingSchedule.addCliff(
params.cliff1Time,
params.vestCliff1Amount
);
grant.vestingSchedule.addCliff(
params.cliff2Time,
params.vestCliff2Amount
);
}
grant.lockupSchedule.totalAmount = amount;
grant.lockupSchedule.startTime = params.startTime;
grant.lockupSchedule.endTime = params.unlockEndTime;
grant.lockupSchedule.addCliff(params.cliff1Time, params.unlockCliff1Amount);
grant.lockupSchedule.addCliff(params.cliff2Time, params.unlockCliff2Amount);
emit TokenGrantCreated(
params.recipient,
amount,
params.startTime,
params.vestEndTime,
params.unlockEndTime
);
return params.recipient;
}
/**
* @notice Truncates a vesting grant.
* This is an *admin* operation callable only by addresses having `TOKEN_GRANTER_ROLE`
* (enforced in `batchRevokeUnvestedTokenAmounts`)
*
* @dev The implementation never updates underlying schedules (vesting or unlock)
* but only the grant amount. This avoids changing the behavior of the grant
* before the point of revocation. Anytime a vesting or unlock schedule is in
* play the corresponding balance functions need to take care to never return
* more than the grant amount less the claimed amount.
*
* Unlike in the `claim` function, here we burn LockedNORI from the grant holder but
* send that BridgedPolygonNORI back to Nori's treasury or an address of Nori's
* choosing (the `to` address). The `claimedAmount` is not changed because this is
* not a claim operation.
*/
function _revokeUnvestedTokens(
address from,
address to,
uint256 atTime,
uint256 amount
) internal {
require(
(atTime == 0 && amount > 0) || (atTime > 0 && amount == 0),
"lNORI: Must specify a revocation time or an amount not both"
);
TokenGrant storage grant = _grants[from];
require(grant.exists, "lNORI: no grant exists");
require(
_hasVestingSchedule(from),
"lNORI: no vesting schedule for this grant"
);
uint256 revocationTime = atTime == 0 && amount > 0
? block.timestamp
: atTime; // atTime of zero indicates a revocation by amount
require(
revocationTime >= block.timestamp,
"lNORI: Revocation cannot be in the past"
);
uint256 vestedBalance = grant.vestingSchedule.availableAmount(
revocationTime
);
require(vestedBalance < grant.grantAmount, "lNORI: tokens already vested");
uint256 revocableQuantity = grant.grantAmount - vestedBalance;
uint256 quantityRevoked;
// amount of zero indicates revocation by time. Amount becomes all remaining tokens
// at *atTime*
if (amount > 0) {
require(amount <= revocableQuantity, "lNORI: too few unvested tokens");
quantityRevoked = amount;
} else {
quantityRevoked = revocableQuantity;
}
grant.grantAmount = grant.grantAmount - quantityRevoked;
grant.lastRevocationTime = revocationTime;
grant.lastQuantityRevoked = quantityRevoked;
super._burn(from, quantityRevoked, "", "");
if (!_bridgedPolygonNori.transfer(to, quantityRevoked)) {
revert("lNORI: transfer of underlying asset failed.");
}
emit UnvestedTokensRevoked(revocationTime, from, quantityRevoked);
}
/**
* @notice Hook that is called before send, transfer, mint, and burn. Used to disable transferring lNORI.
*
* @dev Follows the rules of hooks defined [here](
* https://docs.openzeppelin.com/contracts/4.x/extending-contracts#rules_of_hooks)
*
* ##### Requirements:
*
* - The contract must not be paused.
* - The recipient cannot be the zero address (e.g., no burning of tokens is allowed).
* - One of the following must be true:
* - The operation is minting (which should ONLY occur when BridgedPolygonNORI is being wrapped via `_depositFor`)
* - The operation is a burn and _all_ the following must be true:
* - The operator has `TOKEN_GRANTER_ROLE`.
* - The operator is not operating on their own balance.
* - The transfer amount is <= the sender's unlocked balance.
*/
function _beforeTokenTransfer(
address operator,
address from,
address to,
uint256 amount
) internal override {
bool isMinting = from == address(0);
bool isBurning = to == address(0);
bool operatorIsGrantAdmin = hasRole(TOKEN_GRANTER_ROLE, operator);
bool operatorIsNotSender = operator != from;
bool ownerHasSufficientUnlockedBalance = amount <= unlockedBalanceOf(from);
bool ownerHasSufficientWrappedToken = amount <= balanceOf(from);
if (isBurning && operatorIsNotSender && operatorIsGrantAdmin) {
// Revocation
require(balanceOf(from) >= amount, "lNORI: insufficient balance");
} else if (!isMinting) {
// Withdrawal
require(
ownerHasSufficientUnlockedBalance && ownerHasSufficientWrappedToken,
"lNORI: insufficient balance"
);
}
return super._beforeTokenTransfer(operator, from, to, amount);
}
/**
* @notice Vested balance less any claimed amount at `atTime` (implementation)
*
* @dev Returns true if the there is a grant for *account* with a vesting schedule.
*/
function _hasVestingSchedule(address account) private view returns (bool) {
TokenGrant storage grant = _grants[account];
return grant.exists && grant.vestingSchedule.startTime > 0;
}
/**
* @notice Vested balance less any claimed amount at `atTime` (implementation)
*
* @dev If any tokens have been revoked then the schedule (which doesn't get updated) may return more than the total
* grant amount. This is done to preserve the behavior of the vesting schedule despite a reduction in the total
* quantity of tokens vesting. i.o.w The rate of vesting does not change after calling `revokeUnvestedTokens`.
*/
function _vestedBalanceOf(address account, uint256 atTime)
internal
view
returns (uint256)
{
TokenGrant storage grant = _grants[account];
uint256 balance = this.balanceOf(account);
if (grant.exists) {
if (_hasVestingSchedule(account)) {
balance =
MathUpgradeable.min(
grant.vestingSchedule.availableAmount(atTime),
grant.grantAmount
) -
grant.claimedAmount;
} else {
balance = grant.grantAmount - grant.claimedAmount;
}
}
return balance;
}
/**
* @notice Unlocked balance less any claimed amount
*
* @dev If any tokens have been revoked then the schedule (which doesn't get updated) may return more than the total
* grant amount. This is done to preserve the behavior of the unlock schedule despite a reduction in the total
* quantity of tokens vesting. i.o.w The rate of unlocking does not change after calling `revokeUnvestedTokens`.
*/
function _unlockedBalanceOf(address account, uint256 atTime)
internal
view
returns (uint256)
{
TokenGrant storage grant = _grants[account];
uint256 balance = this.balanceOf(account);
uint256 vestedBalance = _hasVestingSchedule(account)
? grant.vestingSchedule.availableAmount(atTime)
: grant.grantAmount;
if (grant.exists) {
balance =
MathUpgradeable.min(
MathUpgradeable.min(
vestedBalance,
grant.lockupSchedule.availableAmount(atTime)
),
grant.grantAmount
) -
grant.claimedAmount;
}
return balance;
}
function _beforeOperatorChange(address operator, uint256 value)
internal
pure
override
{
revert("lNORI: operator actions disabled");
}
function send(
address,
uint256,
bytes memory
) public pure override {
revert("lNORI: send disabled");
}
function operatorSend(
address,
address,
uint256,
bytes memory,
bytes memory
) public pure override {
revert("lNORI: operatorSend disabled");
}
function transfer(address, uint256) public pure override returns (bool) {
revert("lNORI: transfer disabled");
}
function transferFrom(
address,
address,
uint256
) public pure override returns (bool) {
revert("lNORI: transferFrom disabled");
}
function _beforeRoleChange(bytes32 role, address account)
internal
virtual
override
{
super._beforeRoleChange(role, account);
if (role == TOKEN_GRANTER_ROLE) {
require(
!_grants[account].exists,
"lNORI: Cannot assign role to a grant holder address"
);
}
}
}