VinuSwapPool

The VinuSwapPool contract implements the concentrated liquidity AMM for a specific token pair and fee tier.

Source: contracts/core/VinuSwapPool.sol

Overview

Each pool is an independent market maker that:

• Allows concentrated liquidity provision within price ranges

• Executes swaps between the paired tokens

• Accumulates and distributes fees to liquidity providers

• Maintains a TWAP oracle for price data

State Variables

Immutables

address public immutable override factory;
address public immutable override token0;
address public immutable override token1;
uint24 public immutable override fee;
int24 public immutable override tickSpacing;
uint128 public immutable override maxLiquidityPerTick;
address public immutable feeManager;

Slot0

The primary state storage packed into a single slot:

struct Slot0 {
    // Current sqrt(price) as Q64.96
    uint160 sqrtPriceX96;
    // Current tick
    int24 tick;
    // Most recent observation index
    uint16 observationIndex;
    // Maximum observations stored
    uint16 observationCardinality;
    // Next maximum observations
    uint16 observationCardinalityNext;
    // Protocol fee (4 bits each for token0/token1)
    uint8 feeProtocol;
    // Reentrancy lock
    bool unlocked;
}

Slot0 public override slot0;

Fee Accumulators

uint256 public override feeGrowthGlobal0X128;
uint256 public override feeGrowthGlobal1X128;

Global fee accumulation per unit of liquidity, in Q128.128 format.

Protocol Fees

struct ProtocolFees {
    uint128 token0;
    uint128 token1;
}
ProtocolFees public override protocolFees;

Liquidity

uint128 public override liquidity;

Currently active liquidity (positions covering the current tick).

Ticks

mapping(int24 => Tick.Info) public override ticks;

Tick Bitmap

mapping(int16 => uint256) public override tickBitmap;

Positions

mapping(bytes32 => Position.Info) public override positions;

Observations

Oracle.Observation[65535] public override observations;

Functions

initialize

function initialize(uint160 sqrtPriceX96) external override onlyFactoryOwner

Sets the initial price for the pool. Can only be called once.

Access Control: Only callable by factory owner

Parameters:

Name	Type	Description
sqrtPriceX96	uint160	Initial √price in Q64.96 format

Requirements:

• Caller must be factory owner

• Pool must not already be initialized

• sqrtPriceX96 must be within valid tick range

Events Emitted:

• Initialize(sqrtPriceX96, tick)

Example:

// Initialize at price 1.0 (token0 = token1)
const sqrtPriceX96 = BigNumber.from(2).pow(96);
await pool.initialize(sqrtPriceX96);

---

mint

function mint(
    address recipient,
    int24 tickLower,
    int24 tickUpper,
    uint128 amount,
    bytes calldata data
) external override lock returns (uint256 amount0, uint256 amount1)

Adds liquidity to a position.

Parameters:

Name	Type	Description
recipient	address	Position owner
tickLower	int24	Lower tick boundary
tickUpper	int24	Upper tick boundary
amount	uint128	Liquidity amount to add
data	bytes	Callback data

Returns:

Name	Type	Description
amount0	uint256	Token0 amount required
amount1	uint256	Token1 amount required

Callback: The pool calls IUniswapV3MintCallback.uniswapV3MintCallback(amount0, amount1, data) on msg.sender. The caller must transfer the required tokens to the pool in this callback.

Note: VinuSwap uses Uniswap V3's callback interfaces for compatibility.

Events Emitted:

• Mint(sender, recipient, tickLower, tickUpper, amount, amount0, amount1)

---

burn

function burn(
    int24 tickLower,
    int24 tickUpper,
    uint128 amount
) external override lock returns (uint256 amount0, uint256 amount1)

Removes liquidity from a position. Does not transfer tokens - use collect to withdraw.

Parameters:

Name	Type	Description
tickLower	int24	Lower tick boundary
tickUpper	int24	Upper tick boundary
amount	uint128	Liquidity amount to remove

Returns:

Name	Type	Description
amount0	uint256	Token0 amount owed
amount1	uint256	Token1 amount owed

Events Emitted:

• Burn(msg.sender, tickLower, tickUpper, amount, amount0, amount1)

---

collect

function collect(
    address recipient,
    int24 tickLower,
    int24 tickUpper,
    uint128 amount0Requested,
    uint128 amount1Requested
) external override lock returns (uint128 amount0, uint128 amount1)

Collects tokens owed from a position (from burns and accumulated fees).

Parameters:

Name	Type	Description
recipient	address	Token recipient
tickLower	int24	Lower tick boundary
tickUpper	int24	Upper tick boundary
amount0Requested	uint128	Max token0 to collect
amount1Requested	uint128	Max token1 to collect

Returns:

Name	Type	Description
amount0	uint128	Token0 amount collected
amount1	uint128	Token1 amount collected

Events Emitted:

• Collect(msg.sender, recipient, tickLower, tickUpper, amount0, amount1)

---

swap

function swap(
    address recipient,
    bool zeroForOne,
    int256 amountSpecified,
    uint160 sqrtPriceLimitX96,
    bytes calldata data
) external override lock returns (int256 amount0, int256 amount1)

Executes a swap.

Parameters:

Name	Type	Description
recipient	address	Recipient of swap output
zeroForOne	bool	Direction: true = token0→token1
amountSpecified	int256	Amount to swap (positive = exact input, negative = exact output)
sqrtPriceLimitX96	uint160	Price limit (stops swap if reached)
data	bytes	Callback data

Returns:

Name	Type	Description
amount0	int256	Token0 delta (negative = sent, positive = received)
amount1	int256	Token1 delta (negative = sent, positive = received)

Price Limit Guidelines:

Direction	sqrtPriceLimitX96
zeroForOne = true	Less than current price, greater than MIN_SQRT_RATIO
zeroForOne = false	Greater than current price, less than MAX_SQRT_RATIO

Callback: The pool calls IUniswapV3SwapCallback.uniswapV3SwapCallback(amount0, amount1, data) on msg.sender. The caller must transfer the required input tokens to the pool.

Events Emitted:

• Swap(sender, recipient, amount0, amount1, sqrtPriceX96, liquidity, tick)

---

observe

function observe(uint32[] calldata secondsAgos)
    external
    view
    override
    returns (int56[] memory tickCumulatives, uint160[] memory secondsPerLiquidityCumulativeX128s)

Returns cumulative values from the oracle for TWAP calculations.

Parameters:

Name	Type	Description
secondsAgos	uint32[]	Seconds ago from current time

Returns:

Name	Type	Description
tickCumulatives	int56[]	Cumulative tick values
secondsPerLiquidityCumulativeX128s	uint160[]	Cumulative seconds per liquidity

Example TWAP Calculation:

// Get tick cumulatives for 30 minutes ago and now
const [tickCumulatives] = await pool.observe([1800, 0]);
const averageTick = (tickCumulatives[1] - tickCumulatives[0]) / 1800;
const twapPrice = Math.pow(1.0001, averageTick);

---

increaseObservationCardinalityNext

function increaseObservationCardinalityNext(uint16 observationCardinalityNext)
    external
    override
    lock

Increases the oracle's capacity to store more observations.

Parameters:

Name	Type	Description
observationCardinalityNext	uint16	New cardinality

Note: This operation has a one-time gas cost proportional to the increase. Call before you need the increased capacity.

---

setFeeProtocol

function setFeeProtocol(uint8 feeProtocol0, uint8 feeProtocol1) external override lock

Sets the protocol fee percentage.

Access Control: Only callable by factory owner

Parameters:

Name	Type	Description
feeProtocol0	uint8	Protocol fee for token0 (0 or 4-10)
feeProtocol1	uint8	Protocol fee for token1 (0 or 4-10)

Protocol Fee Calculation:

• Fee = 1/feeProtocol of swap fees

• feeProtocol = 4 → 25% to protocol

• feeProtocol = 5 → 20% to protocol

• feeProtocol = 10 → 10% to protocol

• feeProtocol = 0 → no protocol fee

Events Emitted:

• SetFeeProtocol(feeProtocol0Old, feeProtocol1Old, feeProtocol0, feeProtocol1)

---

collectProtocol

function collectProtocol(
    address recipient,
    uint128 amount0Requested,
    uint128 amount1Requested
) external override lock returns (uint128 amount0, uint128 amount1)

Collects accumulated protocol fees.

Access Control: Only callable by factory owner

Parameters:

Name	Type	Description
recipient	address	Fee recipient
amount0Requested	uint128	Max token0 to collect
amount1Requested	uint128	Max token1 to collect

Returns:

Name	Type	Description
amount0	uint128	Token0 collected
amount1	uint128	Token1 collected

Events Emitted:

• CollectProtocol(msg.sender, recipient, amount0, amount1)

Events

Initialize

event Initialize(uint160 sqrtPriceX96, int24 tick);

Mint

event Mint(
    address sender,
    address indexed owner,
    int24 indexed tickLower,
    int24 indexed tickUpper,
    uint128 amount,
    uint256 amount0,
    uint256 amount1
);

Burn

event Burn(
    address indexed owner,
    int24 indexed tickLower,
    int24 indexed tickUpper,
    uint128 amount,
    uint256 amount0,
    uint256 amount1
);

Swap

event Swap(
    address indexed sender,
    address indexed recipient,
    int256 amount0,
    int256 amount1,
    uint160 sqrtPriceX96,
    uint128 liquidity,
    int24 tick
);

Collect

event Collect(
    address indexed owner,
    address recipient,
    int24 indexed tickLower,
    int24 indexed tickUpper,
    uint128 amount0,
    uint128 amount1
);

SetFeeProtocol

event SetFeeProtocol(
    uint8 feeProtocol0Old,
    uint8 feeProtocol1Old,
    uint8 feeProtocol0New,
    uint8 feeProtocol1New
);

CollectProtocol

event CollectProtocol(
    address indexed sender,
    address indexed recipient,
    uint128 amount0,
    uint128 amount1
);

Error Codes

Code	Meaning
LOK	Locked - reentrancy detected
TLU	Tick lower >= tick upper
TLM	Tick lower < MIN_TICK
TUM	Tick upper > MAX_TICK
AI	Already initialized
M0	Mint amount is 0
AS	Amount specified is 0
IIA	Invalid input amount
SPL	Invalid sqrt price limit
L	Liquidity overflow

Constants

int24 internal constant MIN_TICK = -887272;
int24 internal constant MAX_TICK = 887272;
uint160 internal constant MIN_SQRT_RATIO = 4295128739;
uint160 internal constant MAX_SQRT_RATIO = 1461446703485210103287273052203988822378723970342;

Related

• VinuSwapFactory

• SwapRouter

• NonfungiblePositionManager