SEI DEX MCP

import { ethers } from 'ethers'; import { DragonSwapV1Config } from '../types/dragonswap.js'; const factoryAbi = [ 'function allPairs(uint256) external view returns (address pair)', 'function allPairsLength() external view returns (uint256)', ]; const pairAbi = [ 'function token0() external view returns (address)', 'function token1() external view returns (address)', 'function getReserves() external view returns (uint112 reserve0, uint112 reserve1, uint32 blockTimestampLast)', ]; const erc20Abi = [ 'function symbol() external view returns (string)', 'function decimals() external view returns (uint8)', 'function approve(address spender, uint256 amount) external returns (bool)', ]; const routerAbi = [ 'function getAmountsOut(uint amountIn, address[] memory path) public view returns (uint[] memory amounts)', 'function swapExactTokensForTokens(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline) external returns (uint[] memory amounts)', ]; const wseiAbi = ['function deposit() public payable', 'function withdraw(uint wad) public']; export class DragonSwapV1Service { private provider: ethers.JsonRpcProvider; private factoryContract: ethers.Contract; private routerContractReadOnly: ethers.Contract; // For read operations (quotes) private wallet: ethers.Wallet | undefined; private routerContract: ethers.Contract | undefined; // For write operations (swaps) constructor(private config: DragonSwapV1Config, private privateKey?: string) { this.provider = new ethers.JsonRpcProvider(config.rpcUrl); this.factoryContract = new ethers.Contract(config.factoryAddress, factoryAbi, this.provider); this.routerContractReadOnly = new ethers.Contract(config.routerAddress, routerAbi, this.provider); } private _getWallet(): ethers.Wallet { if (this.wallet) { return this.wallet; } if (!this.privateKey || this.privateKey.length !== 64) { throw new Error('A valid 64-character private key is not configured. Please provide it in your session configuration.'); } this.wallet = new ethers.Wallet(this.privateKey, this.provider); this.routerContract = new ethers.Contract(this.config.routerAddress, routerAbi, this.wallet); return this.wallet; } async getAllPools(): Promise<any[]> { const pairCount = await this.factoryContract.allPairsLength(); const pools: any[] = []; for (let i = 0; i < pairCount; i++) { try { const pairAddress = await this.factoryContract.allPairs(i); if (pairAddress === ethers.ZeroAddress) { continue; } const pairContract = new ethers.Contract(pairAddress, pairAbi, this.provider); const [token0Address, token1Address, reserves] = await Promise.all([ pairContract.token0(), pairContract.token1(), pairContract.getReserves(), ]); const token0Contract = new ethers.Contract(token0Address, erc20Abi, this.provider); const token1Contract = new ethers.Contract(token1Address, erc20Abi, this.provider); const [token0Symbol, token1Symbol, token0Decimals, token1Decimals] = await Promise.all([ token0Contract.symbol(), token1Contract.symbol(), token0Contract.decimals(), token1Contract.decimals(), ]); pools.push({ pairAddress, token0: { address: token0Address, symbol: token0Symbol, decimals: token0Decimals.toString(), }, token1: { address: token1Address, symbol: token1Symbol, decimals: token1Decimals.toString(), }, reserves: { reserve0: reserves.reserve0.toString(), reserve1: reserves.reserve1.toString(), }, }); } catch (error) { console.error(`Failed to fetch details for pair at index ${i}. Skipping.`); } } return pools; } async getQuote(tokenIn: string, tokenOut: string, amountIn: string): Promise<string> { const tokenInContract = new ethers.Contract(tokenIn, erc20Abi, this.provider); const decimals = await tokenInContract.decimals(); const parsedAmountIn = ethers.parseUnits(amountIn, decimals); const amountsOut = await this.routerContractReadOnly.getAmountsOut(parsedAmountIn, [tokenIn, tokenOut]); const tokenOutContract = new ethers.Contract(tokenOut, erc20Abi, this.provider); const outDecimals = await tokenOutContract.decimals(); return ethers.formatUnits(amountsOut[1], outDecimals); } async executeSwap(tokenIn: string, tokenOut: string, amountIn: string): Promise<string> { const wallet = this._getWallet(); const routerContract = this.routerContract!; const tokenInContract = new ethers.Contract(tokenIn, erc20Abi, wallet); const decimals = await tokenInContract.decimals(); const parsedAmountIn = ethers.parseUnits(amountIn, decimals); // Approve the router to spend the tokens const approveTx = await tokenInContract.approve(this.config.routerAddress, parsedAmountIn); await approveTx.wait(); const amountsOut = await this.routerContractReadOnly.getAmountsOut(parsedAmountIn, [tokenIn, tokenOut]); const amountOutMin = (amountsOut[1] * BigInt(99)) / BigInt(100); // 1% slippage tolerance const deadline = Math.floor(Date.now() / 1000) + 60 * 20; // 20 minutes from now const tx = await routerContract.swapExactTokensForTokens( parsedAmountIn, amountOutMin, [tokenIn, tokenOut], wallet.address, deadline ); await tx.wait(); return tx.hash; } async wrapSei(amount: string): Promise<string> { const wallet = this._getWallet(); console.log(`Attempting to wrap ${amount} SEI`); const wseiContract = new ethers.Contract(this.config.wseiAddress, wseiAbi, wallet); const valueToWrap = ethers.parseUnits(amount, 6); console.log(`Calculated value (in wei, 6 decimals): ${valueToWrap.toString()}`); console.log(`wSEI Contract Address: ${this.config.wseiAddress}`); console.log(`Signer Address: ${wallet.address}`); try { const tx = await wseiContract.deposit({ value: valueToWrap, }); console.log('Transaction sent:', tx.hash); await tx.wait(); console.log('Transaction confirmed.'); return tx.hash; } catch (error) { console.error('Error during wrapSei execution:', error); throw error; // Re-throw the error to be caught by the tool handler } } async approveWsei(amount: string): Promise<string> { const wallet = this._getWallet(); const wseiContract = new ethers.Contract(this.config.wseiAddress, erc20Abi, wallet); const decimals = await wseiContract.decimals(); const parsedAmount = ethers.parseUnits(amount, decimals); const approveTx = await wseiContract.approve(this.config.routerAddress, parsedAmount); await approveTx.wait(); return approveTx.hash; } }