Set Up Your Contract

// SPDX-License-Identifier: GPL-2.0-or-later
pragma solidity =0.7.6;
pragma abicoder v2;

import '@uniswap/v3-core/contracts/interfaces/IUniswapV3Pool.sol';
import '@uniswap/v3-core/contracts/libraries/TickMath.sol';
import '@openzeppelin/contracts/token/ERC721/IERC721Receiver.sol';
import '@uniswap/v3-periphery/contracts/interfaces/ISwapRouter.sol';
import '@uniswap/v3-periphery/contracts/interfaces/IRamsesV3PositionManager.sol';
import '@uniswap/v3-periphery/contracts/libraries/TransferHelper.sol';
import '@uniswap/v3-periphery/contracts/base/LiquidityManagement.sol';

contract LiquidityExamples is IERC721Receiver {

    address public constant DAI = 0x6B175474E89094C44Da98b954EedeAC495271d0F;
    address public constant USDC = 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48;

    uint24 public constant poolFee = 3000;

    IRamsesV3PositionManager public immutable nonfungiblePositionManager;

    struct Deposit {
        address owner;
        uint128 liquidity;
        address token0;
        address token1;
    }

    mapping(uint256 => Deposit) public deposits;

    constructor(
        IRamsesV3PositionManager _nonfungiblePositionManager,
        address _factory,
        address _WETH9
    ) PeripheryImmutableState(_factory, _WETH9) {
        nonfungiblePositionManager = _nonfungiblePositionManager;
    }

    function onERC721Received(
        address operator,
        address,
        uint256 tokenId,
        bytes calldata
    ) external override returns (bytes4) {
        _createDeposit(operator, tokenId);
        return this.onERC721Received.selector;
    }

    function _createDeposit(address owner, uint256 tokenId) internal {
        (, , address token0, address token1, , , , uint128 liquidity, , , , ) =
            nonfungiblePositionManager.positions(tokenId);

        deposits[tokenId] = Deposit({owner: owner, liquidity: liquidity, token0: token0, token1: token1});
    }