如何使用 Kuru Flow 在您的应用中添加代币兑换

const KURU_FLOW_API = "https://ws.kuru.io";

async function generateToken(userAddress: string) {
  const response = await fetch(`${KURU_FLOW_API}/api/generate-token`, {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ user_address: userAddress }),
  });

  return response.json();
  // Returns: { token: string, expires_at: number, rate_limit: { rps: number, burst: number } }
}

const KURU_FLOW_API = "https://ws.kuru.io";

// Your wallet address to receive referral fees
const REFERRER_ADDRESS = "0xYOUR_WALLET_ADDRESS_HERE";
const REFERRER_FEE_BPS = 50; // 0.5%

async function getQuote(
  userAddress: string,
  tokenIn: string,
  tokenOut: string,
  amount: string,
  token: string
) {
  const response = await fetch(`${KURU_FLOW_API}/api/quote`, {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
      Authorization: `Bearer ${token}`,
    },
    body: JSON.stringify({
      userAddress,
      tokenIn,
      tokenOut,
      amount,
      autoSlippage: true,
      referrerAddress: REFERRER_ADDRESS,
      referrerFeeBps: REFERRER_FEE_BPS,
    }),
  });

  return response.json();
}

export interface QuoteResponse {
  type: string;
  status: "success" | "error";
  output: string;           // Expected output amount (in wei)
  minOut: string;           // Minimum output with slippage
  transaction: {
    to: string;             // Router contract address
    calldata: string;       // Transaction calldata (WITHOUT 0x prefix!)
    value: string;          // Native MON amount (non-zero when swapping native MON)
  };
  gasPrices: {
    slow: string;
    standard: string;
    fast: string;
    rapid: string;
    extreme: string;
  };
  message?: string;         // Error message if status is "error"
}

import { useState } from "react";
import { useAccount, useReadContract } from "wagmi";
import { parseUnits } from "viem";
import type { QuoteResponse } from "@/lib/kuru-flow";

// Token addresses
const NATIVE_MON = "0x0000000000000000000000000000000000000000" as const;
const USDC = "0x754704Bc059F8C67012fEd69BC8A327a5aafb603" as const;

const ERC20_ABI = [
  {
    name: "allowance",
    type: "function",
    stateMutability: "view",
    inputs: [
      { name: "owner", type: "address" },
      { name: "spender", type: "address" },
    ],
    outputs: [{ name: "", type: "uint256" }],
  },
] as const;

// Inside your component:
const { address } = useAccount();
const [amount, setAmount] = useState("");
const [quote, setQuote] = useState<QuoteResponse | null>(null);

const tokenIn = USDC; // Example: swapping USDC
const isNativeToken = tokenIn === NATIVE_MON;
const amountWei = amount ? parseUnits(amount, 6) : BigInt(0);

// Check allowance against router address from quote (skip for native MON)
const { data: allowance } = useReadContract({
  address: tokenIn,
  abi: ERC20_ABI,
  functionName: "allowance",
  args: address && quote?.transaction?.to
    ? [address, quote.transaction.to as `0x${string}`]
    : undefined,
  query: {
    enabled: !isNativeToken, // Don't check allowance for native token
  },
});

// Native tokens don't need approval
const needsApproval = !isNativeToken && allowance !== undefined && amountWei > allowance;

import { encodeFunctionData } from "viem";
import { useSendTransaction } from "wagmi";

const APPROVE_ABI = [
  {
    name: "approve",
    type: "function",
    stateMutability: "nonpayable",
    inputs: [
      { name: "spender", type: "address" },
      { name: "amount", type: "uint256" },
    ],
    outputs: [{ name: "", type: "bool" }],
  },
] as const;

// Inside your component:
const { sendTransaction: sendApproveTx } = useSendTransaction();

const handleApprove = () => {
  if (!quote?.transaction?.to) return;

  const data = encodeFunctionData({
    abi: APPROVE_ABI,
    functionName: "approve",
    args: [quote.transaction.to as `0x${string}`, amountWei],
  });

  sendApproveTx({
    to: tokenIn,
    data,
  });
};

// Inside your component:
const { sendTransaction: sendSwapTx } = useSendTransaction();

const handleSwap = () => {
  if (!quote || quote.status !== "success") return;

  // IMPORTANT: Add 0x prefix to calldata
  const calldata = quote.transaction.calldata.startsWith("0x")
    ? quote.transaction.calldata
    : `0x${quote.transaction.calldata}`;

  sendSwapTx({
    to: quote.transaction.to as `0x${string}`,
    data: calldata as `0x${string}`,
    value: BigInt(quote.transaction.value || "0"),
  });
};

// Replace with YOUR wallet address to receive referral fees
export const REFERRER_ADDRESS = "0xYOUR_WALLET_ADDRESS_HERE";

// Fee in basis points (50 = 0.5%, 100 = 1%)
export const REFERRER_FEE_BPS = 50;