Exchange

This is a V2 Pool smart contract to expand ERC20 that is created with every liquidity pair. The Factory deploys this as new pool creation is requested. Although the Factory actually stores the two tokens of a pair and swapping takes place through it, the Exchange Contract must be called for liquidity to be provided or taken.

Code

Github Link: (Will be updated after official launch)

Events, Read-Only Functions, and State-Changing Functions

Events

Events

Transfer

event Transfer(address indexed from, address indexed to, uint amount);

• ERC20 Standard

• Event log of Transfer/Mint/Burn

Approval

event Approval(address indexed holder, address indexed spender, uint256 amount);

• ERC20 Standard

• Event log of Approvals

ChangeMiningRate

event ChangeMiningRate(uint256 _mining);

• Event log of mining rate change

ChangeFee

event ChangeFee(uint256 _fee);

• Event log of trading fee rate changes

UpdateMiningIndex

event UpdateMiningIndex(uint lastMined, uint miningIndex);

• Event log of pairs’ mining index changes

• lastMined : Factory.mined() value at the time index is updated

• miningIndex : pairs’ miningIndex value at the time

GiveReward

event GiveReward(address user, uint amount, uint lastIndex, uint rewardSum);

• Event log of when mined Governance Token is claimed and distributed

• user : address of the user who claimed

• amount : the amount of Governance Token claimed

• lastIndex : index result of the pair of the wallet after claiming

• rewardSum : The amount of Governance Token that has been accrued so far

ExchangePos

event ExchangePos(address token0, uint amount0, address token1, uint amount1);

• Event log of POS transactions

• token0 : token address delivered by the user

• amount0 : the amount of tokens delivered by the user

• token1 : token address received by the user

• amount1 : the amount of tokens received by the user

ExchangeNeg

event ExchangeNeg(address token0, uint amount0, address token1, uint amount1);

• Event log of NEG transactions

• token0 : token address delivered by the user

• amount0 : the amount of tokens delivered by the user

• token1 : token address received by the user

• amount1 : the amount of tokens received by the user

AddLiquidity

event AddLiquidity(address user, address token0, uint amount0, address token1, uint amount1, uint liquidity);

• Event log of liquidity additions

• liquidity : the amount of LP tokens minted due to additional liquidity

RemoveLiquidity

event RemoveLiquidity(address user, address token0, uint amount0, address token1, uint amount1, uint liquidity);

• Event log of liquidity removals

• liquidity : the amount of LP tokens burned due to liquidity removal

Read-Only Functions

Read-Only Functions

name

• KlaySwap LP

symbol

• "KSLP" + " " + symbolA + "-" + symbolB

decimals

• 18

totalSupply

• mint/burn depending on liquidity addition/removal

balanceOf

• Number of LP tokens held by each address

allowance

• Status of approval to spender for each address

factory

• The factory address where the LP smart contract is deployed

tokenA

• The first token address composed of the pair

• When KLAY is one part of the pair, tokenA == 0x0

tokenB

• The second token address composed of the pair

fee

• Transaction fee for the pair

• It is a value between 0 and 100, in units of 0.01%

• 1 == 0.01%, 100 == 1%

mining

• The mining rate of the pair

• It is a value between 0 and 100, in units of 1%

• e.g. If mining is 10, the pair has claim authority for 10% of the quantity mined per block in the factory.

lastMined

• Factory.mined() value at the last time the pair updated the index

miningIndex

• Index value of the last recorded pair

userLastIndex

• mapping(address => uint)

• Stores the index value at the time of last reward for each user

userRewardSum

• mapping(address => uint )

• Stores the cumulatively claimed KSP quantity value for each user

getCurrentPool

function getCurrentPool() public view returns (uint, uint)

• Returns the liquidity quantity of the two assets in the current pool

estimatePos

function estimatePos(address token, uint amount) public view returns (uint)

• When a request is made to sell the amount of the corresponding token through a POS transaction, the expected receiving amount of the opposite token is returned.

estimateNeg

function estimateNeg(address token, uint amount) public view returns (uint)

• When a request is made to purchase the amount of the corresponding token through a NEG transaction, the expected payment amount of the opposite token is returned.

State-Changing Functions

State-Changing Functions

transfer

function transfer(address _to, uint _value) public returns (bool)

• KIP7 Standard

• Method for KSP token transfer

transferFrom

function transferFrom(address _from, address _to, uint _value) public returns (bool)

• KIP7 Standard

• Method to transfer tokens on behalf of the approved wallet

approve

function approve(address _spender, uint _value) public returns (bool)

• KIP7 Standard

• Method to approve transfer as much as value to the spender

updateMiningIndex

function updateMiningIndex() public

• Method to update the value of the pair contract based on the current Factory.mined() value

• Anyone can call in real time. Even if no one calls it, it calls itself if necessary.

claimReward

function claimReward() public

• Method that a user calls to claim the claimable KSP that has accumulated for the pair

• When called, KSP is claimed from the Factory and paid to msg.sender

• Even if the method is not called directly, it is automatically called when the LP token balance of the user’s wallet changes.

  • When liquidity is added

  • When liquidity is removed

  • When LP tokens are sent

  • When LP tokens are received

addKlayLiquidity

function addKlayLiquidity(uint amount) public payable

• Method used to provide liquidity when tokenA is KLAY

• Liquidity of the KLAY msg.value and tokenB amount is provided.

• After liquidity is provided, the LP token corresponding to the pool share is minted in the msg.sender wallet.

• If the pair ratio is wrong, as much liquidity as possible is supplied at the current pair ratio, and the remaining tokens are returned to msg.sender.

• If there is claimable KSP when called, the claim proceeds to msg.sender.

addKlayLiquidityWithLimit

function addKlayLiquidityWithLimit(uint amount, uint minAmountA, uint minAmountB) public payable

• Method used to provide liquidity when tokenA is KLAY

• Liquidity of the KLAY msg.value and tokenB amount is provided.

• Set the minimum amount of tokenA and tokenB to be used for liquidity supply using minAmountA, minAmountB.

• After liquidity is provided, the LP token corresponding to the pool share is minted in the msg.sender wallet.

• If the pair ratio is wrong, as much liquidity as possible is supplied at the current pair ratio, and the remaining tokens are returned to msg.sender.

• If there is claimable KSP when called, the claim proceeds to msg.sender.

addKctLiquidity

function addKctLiquidity(uint amountA, uint amountB) public

• Method used to provide liquidity when tokenA is KIP7 standard token

• Liquidity of the number of tokenA amountA and tokenB amountB is provided.

• After liquidity is provided, the LP token corresponding to the pool share is minted in the msg.sender wallet.

• If the pair ratio is wrong, as much liquidity as possible is supplied at the current pair ratio, and the remaining tokens are returned to msg.sender.

• If there is claimable KSP when called, the claim proceeds to msg.sender.

addKctLiquidityWithLimit

function addKctLiquidityWithLimit(uint amountA, uint amountB, uint minAmountA, uint minAmountB) public

• Method used to provide liquidity when tokenA is KIP7 standard token

• Liquidity of the number of tokenA amountA and tokenB amountB is provided.

• Set the minimum amount of tokenA and tokenB to be used for liquidity supply using minAmountA, minAmountB.

• After liquidity is provided, the LP token corresponding to the pool share is minted in the msg.sender wallet.

• If the pair ratio is wrong, as much liquidity as possible is supplied at the current pair ratio, and the remaining tokens are returned to msg.sender.

• If there is claimable KSP when called, the claim proceeds to msg.sender.

removeLiquidity

function removeLiquidity(uint amount) public

• Returns the amount of LP tokens, and distributes the corresponding tokenA and tokenB to the msg.sender wallet

• The returned LP token amount is burned

• If there is claimable KSP when called, the claim proceeds to msg.sender.

removeLiquidityWithLimit

function removeLiquidityWithLimit(uint amount, uint minAmountA, uint minAmountB) public

• Returns the amount of LP tokens, and distributes the corresponding tokenA and tokenB to the msg.sender wallet

• Set the minimum amount for the returned tokenA and tokenB amounts by using minAmountA, minAmountB.

• The returned LP token amount is burned

• If there is claimable KSP when called, the claim proceeds to msg.sender.