ZivoeRewards.sol

Staking for Native Protocol Token(s)

Introduction

This contract facilitates staking and yield distribution.

This contract has the following responsibilities:

• Allows staking and unstaking of modular "stakingToken".

• Allows claiming yield distributed / "deposited" to this contract.

• Allows multiple assets to be added as "rewardToken" for distributions.

• Vests rewardTokens linearly overtime to stakers.

State Variables

Type	Name	Description
address	GBL	The ZivoeGlobals contract.
address[]	rewardTokens	Array of ERC20 tokens distributed as rewards (if present).
uint256	_totalSupply	Total supply of (non-transferrable) LP tokens for reards contract.
mapping(address => Reward)	rewardData	Contains rewards information for each rewardToken.
mapping(address => mapping(address => (uint256))	accountRewardPerTokenPaid	The order is account -> rewardAsset -> amount.
mapping(address => mapping(address => (uint256))	rewards	The order is account -> rewardAsset -> amount.
mapping(address => uint256)	_balances	Contains LP token balance of each account (is 1:1 ratio with amount deposited).
IERC20	stakingToken	IERC20 wrapper for the stakingToken (deposited to receive LP tokens).

Reward

This struct stores information for reward tokens.

Type	Name	Description
uint256	rewardsDuration	How long rewards take to vest, e.g. 30 days.
uint256	periodFinish	When current rewards will finish vesting.
uint256	rewardRate	Rewards emitted per second.
uint256	lastUpdateTime	Last time this data struct was updated.
uint256	rewardPerTokenStored	Last snapshot of rewardPerToken taken.

Sections

Read Functions

• balanceOf() - Returns the amount of tokens owned by "account", received when depositing via stake().

• getRewardForDuration() - Returns the total amount of rewards being distributed to everyone for current rewardsDuration.

• totalSupply() - Returns the amount of tokens in existence; these are minted and burned when depositing or withdrawing.

• viewAccountRewardPerTokenPaid() - Returns the last snapshot of rewardPerTokenStored taken for a reward asset.

• viewRewards() - Returns the rewards earned of a specific rewardToken for an address.

• earned() - Provides information on the rewards available for claim.

• lastTimeRewardApplicable() - Helper function for assessing distribution timelines.

• rewardPerToken() - Cumulative amount of rewards distributed per LP token.

Write Functions

• addReward() - Adds a new asset as a reward to this contract.

• depositReward() - Deposits a reward to this contract for distribution.

• fullWithdraw() - Simultaneously calls withdraw() and getRewards() for convenience.

• stake() - Stakes the specified amount of stakingToken to this contract.

• stakeFor() - Stakes the specified amount of stakingToken to this contract, awarded to someone else.

• getRewards() - Claim rewards for all possible _rewardTokens.

• withdraw() - Withdraws the specified amount of stakingToken from this contract.

Events

• RewardAdded()

• RewardDeposited()

• RewardDistributed()

• Staked()

• StakedFor()

• Withdrawn()

Read Functions

balanceOf()

Returns the amount of tokens owned by "account", received when depositing via stake().

function balanceOf(
    address account
) external view returns (uint256 amount);

Type	Name	Description
address	account	The account to view information of.

Returns

Type	Name	Description
uint256	amount	The amount of tokens owned by "account".

getRewardForDuration()

Returns the total amount of rewards being distributed to everyone for current rewardsDuration.

function getRewardForDuration(
    address _rewardsToken
) external view returns (uint256 amount);

Type	Name	Description
address	_rewardsToken	The asset that's being distributed.

Returns

Type	Name	Description
uint256	amount	The amount of rewards being distributed.

totalSupply()

Returns the amount of tokens in existence; these are minted and burned when depositing or withdrawing.

function totalSupply() external view returns (uint256 amount);

Returns

Type	Name	Description
uint256	amount	The amount of tokens in existence.

viewAccountRewardPerTokenPaid()

Returns the last snapshot of rewardPerTokenStored taken for a reward asset.

function viewAccountRewardPerTokenPaid(
    address account, 
    address rewardAsset
) external view returns (uint256 amount);

Type	Name	Description
address	account	The account to view information of.
address	rewardAsset	The reward token for which we want to return the rewardPerTokenstored.

Returns

Type	Name	Description
uint256	amount	The latest up-to-date value of rewardPerTokenStored.

viewRewards()

Returns the rewards earned of a specific rewardToken for an address.

function viewRewards(
    address account,
    address rewardAsset
) external view returns (uint256 amount);

Type	Name	Description
address	account	The account to view information of.
address	rewardAsset	The asset earned as a reward.

Returns

Type	Name	Description
uint256	amount	The amount of rewards earned.

earned()

Provides information on the rewards available for claim.

function earned(
    address account, 
    address _rewardsToken
) public view returns (uint256 amount);

Type	Name	Description
address	account	The account to view information of.
address	_rewardsToken	The asset that's being distributed.

Returns

Type	Name	Description
uint256	amount	The amount of rewards earned.

lastTimeRewardApplicable()

Helper function for assessing distribution timelines.

function lastTimeRewardApplicable(
    address _rewardsToken
) public view returns (uint256 timestamp); 

Type	Name	Description
address	_rewardsToken	The asset that's being distributed.

Returns

Type	Name	Description
uint256	timestamp	The most recent time (in UNIX format) at which rewards are available for distribution.

rewardPerToken()

Cumulative amount of rewards distributed per LP token.

function rewardPerToken(
    address _rewardsToken
) public view returns (uint256 amount);

Type	Name	Description
address	_rewardsToken	The asset that's being distributed.

Returns

Type	Name	Description
uint256	amount	The cumulative amount of rewards distributed per LP token.

Write Functions

addReward()

Adds a new asset as a reward to this contract.

function addReward(
    address _rewardsToken, 
    uint256 _rewardsDuration
) external;

Type	Name	Description
address	_rewardsToken	The asset that's being distributed
uint256	_rewardsDuration	How long rewards take to vest, e.g. 30 days (denoted in seconds).

Emits the RewardAdded() event

depositReward()

Deposits a reward to this contract for distribution.

function depositReward(
    address _rewardsToken, 
    uint256 reward
) external updateReward(address(0)) nonReentrant;

Type	Name	Description
address	_rewardsToken	The asset that's being distributed.
uint256	reward	The amount of the _rewardsToken to deposit.

Emits the RewardDeposited() event

fullWithdraw()

Simultaneously calls withdraw() and getRewards() for convenience.

function fullWithdraw() external;

Emits the Withdrawn() and RewardDistributed() event(s)

stake()

Stakes the specified amount of stakingToken to this contract.

function stake(uint256 amount) external nonReentrant updateReward(_msgSender());

Type	Name	Description
uint256	amount	The amount of the _rewardTokens to deposit.

Emits the Staked() event

stakeFor()

Stakes the specified amount of stakingToken to this contract, awarded to someone else.

function stakeFor(
    uint256 amount, 
    address account
) external nonReentrant updateReward(account);

Type	Name	Description
uint256	amount	The amount of the _rewardsToken to deposit.
address	account	The account to stake for (that ultimately receives the stake).

Emits the StakedFor() event

getRewards()

Claim rewards for all possible _rewardTokens.

function getRewards() public updateReward(_msgSender());

Emits the RewardDistributed() event

withdraw()

Withdraws the specified amount of stakingToken from this contract.

function withdraw(uint256 amount) public nonReentrant updateReward(_msgSender());

Type	Name	Description
uint256	amount	The amount of the _rewardsToken to withdraw.

Emits the Withdrawn() event

Events

RewardAdded()

Emitted during addReward()

event RewardAdded(address indexed reward);

Type	Indexed	Name	Description
address	True	reward	The asset that's being distributed.

RewardDeposited()

Emitted during depositReward()

event RewardDeposited(
    address indexed reward, 
    uint256 amount, 
    address indexed depositor
);

Type	Indexed	Name	Description
address	True	reward	The asset that's being deposited.
uint256	False	amount	The amount deposited.
address	True	depositor	The _msgSender() who deposited said reward.

RewardDistributed()

Emitted during ZivoeRewards.sol

event RewardDistributed(
    address indexed account, 
    address indexed rewardsToken, 
    uint256 reward
);

Type	Indexed	Name	Description
address	True	account	The account receiving a reward.
address	True	rewardsToken	The ERC20 asset distributed as a reward.
uint256	False	reward	The amount of "rewardsToken" distributed.

Staked()

Emitted during stake()

event Staked(address indexed account, uint256 amount);

Type	Indexed	Name	Description
address	True	account	The account staking "stakingToken".
uint256	False	amount	The amount of "stakingToken" staked.

StakedFor()

Emitted during stakeFor()

event StakedFor(
    address indexed account, 
    uint256 amount, 
    address indexed by
);

Type	Indexed	Name	Description
address	True	account	The account receiveing the staked position of "stakingToken".
uint256	False	amount	The amount of "stakingToken" staked.
address	True	by	The account facilitating the staking.

Withdrawn()

Emitted during withdraw()

event Withdrawn(address indexed account, uint256 amount);

Type	Indexed	Name	Description
address	True	account	The account withdrawing "stakingToken".
uint256	False	amount	The amount of "stakingToken" to withdraw.