Liquid Staking Contract

This contract allows users on Astar to stake their DOT to receive a share of sDot based on their amount of the total deposited DOT. Every time updateReward(token) is called, we distribute WASTR as rewards to users that are currently staking inside this contract, and they can claim it using harvest, and operator will call withdrawPendingBond with a fixed interval to withdraw all DOTs that are pending to be bonded in order to stake in the relaychain, operator will also call depositUnbonded with a fixed interval to individully distribute to users that have already initiated unstake request in order to claim back their DOT.

Deployed

Environment	Address
Shibuya	0x636F98F63501b72B2916338B903834124845DA81
ASTAR	0xF8d6A9071f54CF9A802De7E2f672A549E089CCD3

Usage

DOT & sDOT

Please note that both DOT & sDOT are haveing only 10 decimals.

Method	Usage
`balanceOf(_account)`	sDOT balance
`totalSupply()`	Total issuance of sDOT
`internalDotBalance()`	Total staked DOT, this gets updated on user `stake()` / `unstake()`

Getter functions

Method	Usage	Return
`getUserInfo(_account, _rewardToken)`	Get user info with reward respective to each reward token(i.e. WASTR)	`uint256 amount, uint256 pendingUnbondAmount, uint256 claimableUnbondedAmount, mapping(IERC20Upgradeable => uint256) rewardDebt, mapping(IERC20Upgradeable => uint256) unclaimedReward`
`getPendingReward(_account, _rewardToken)`	Get pending reward of an user	`uint256 pendingReward`
`getRewardTokensLength()`	Get the number of reward tokens	`uint256 rewardTokensLength`

APY

WASTR APY = Daily WASTR Rate * 365 / internalDOTBalance()

LiquidStaking

Method	Usage
`stake(_amount)`	Stake DOT
`unstake(_amount)`	Unstake DOT(i.e. Unstake instantly/Add up each user's pending unbonding amount and initiate unstake request for operator to withdraw)
`harvest(_rewardToken)`	Harvest particular reward token
`claimDOT()`	Claim back DOT 1:1 + gained DOT and burns sDot

Owner-only functions (with timelock implemented)

Method	Usage
`withdrawPendingBond()`	Withdraw all DOTs that are pending to be bonded in order to stake in the relaychain
`depositUnbonded(_account, _amount)`	Deposit unbonded DOTs to contract and let individual user who initiated unstake request be able to claim back DOTs
`setOperator(_operator)`	Change operator's address
`setTransactionFee(_newTransactionFee)`	Change dot transaction fee
`pause()`	Implement an emergency stop mechanism to the contract
`unpause()`	Unpause the contract to return its state to normal
`addRewardToken(_rewardToken)`	Add token as Reward Token
`removeRewardToken(_rewardToken)`	Remove token from Reward Token List

Event types

Events	Description
`Staked(address indexed user, uint256 amount)`	Emitted when a user stakes DOT
`InstantUnstaked(address indexed user, uint256 amount, uint256 timestamp)`	Emitted only when a user unstakes DOT instanly(i.e. without operator having withdrawn pending bond)
`Unstaked(address indexed user, uint256 amount, uint256 timestamp)`	Emitted when a user unstakes DOT
`ClaimedUnbond(address indexed user, uint256 amount, uint256 timestamp)`	Emitted when a user claims back DOT after unbonding period ends
`Harvested(address indexed user, address indexed rewardToken, uint256 amount)`	Emitted when a user harvests ASTR rewards
`WithdrawedPendingBond(uint256 totalPendingBondAmount, uint256 timestamp)`	Emitted when operator withdraws all pending bond DOT from contract
`DepositedUnbonded(address indexed user, uint256 amount, uint256 timestamp)`	Emitted when operator deposits unbonded DOT to contract
`NewFeeCollectorSet(address newFeeCollector)`	Emitted when owner sets a new feeCollector
`NewOperatorSet(address newOperator)`	Emitted when owner sets a new operator
`NewTransactionFeeSet(uint256 newTransactionFee)`	Emitted when owner sets a new transaction fee
`RewardTokenAdded(address token)`	Emitted when owner adds a token to the reward tokens list
`RewardTokenRemoved(address token)`	Emitted when owner removes a token from the reward tokens list

0xdevant/dot-liquid-staking