/**
 * Uniswap: Universal Router with Permit2 integration
 * 
 * This example demonstrates how to use Universal Router for complex multi-step transactions
 * with Permit2 signature-based approvals.
 * 
 * Universal Router supports:
 * - Token swaps (Uniswap v2/v3)
 * - NFT operations
 * - Permit2 approvals
 * - WETH wrapping/unwrapping
 * - Multiple commands in one transaction
 */

import { createWalletRpcClient } from '../../src/utils/chain-config.js';
import { getUniswapUniversalRouter, getPermit2Address } from '../../src/utils/addresses.js';
import { getTokenMetadata, parseTokenAmount } from '../../src/utils/tokens.js';
import { waitForTransaction } from '../../src/utils/rpc.js';
import type { Address, Hex } from 'viem';

const CHAIN_ID = 1; // Mainnet (change to 8453 for Base, etc.)
const PRIVATE_KEY = process.env.PRIVATE_KEY as `0x${string}`;

// Universal Router ABI
const UNIVERSAL_ROUTER_ABI = [
  {
    name: 'execute',
    type: 'function',
    stateMutability: 'payable',
    inputs: [
      { name: 'commands', type: 'bytes' },
      { name: 'inputs', type: 'bytes[]' },
    ],
    outputs: [],
  },
  {
    name: 'execute',
    type: 'function',
    stateMutability: 'payable',
    inputs: [
      { name: 'commands', type: 'bytes' },
      { name: 'inputs', type: 'bytes[]' },
      { name: 'deadline', type: 'uint256' },
    ],
    outputs: [],
  },
] as const;

/**
 * Universal Router command types
 * See: https://github.com/Uniswap/universal-router/blob/main/contracts/Commands.sol
 */
const COMMANDS = {
  V3_SWAP_EXACT_IN: 0x00,
  V3_SWAP_EXACT_OUT: 0x01,
  PERMIT2_TRANSFER_FROM: 0x02,
  PERMIT2_PERMIT_BATCH: 0x03,
  SWEEP: 0x04,
  TRANSFER: 0x05,
  PAY_PORTION: 0x06,
  V2_SWAP_EXACT_IN: 0x08,
  V2_SWAP_EXACT_OUT: 0x09,
  PERMIT2_PERMIT: 0x0a,
  WRAP_ETH: 0x0b,
  UNWRAP_WETH: 0x0c,
  PERMIT2_TRANSFER_FROM_BATCH: 0x0d,
} as const;

/**
 * Encode V3 swap exact input command
 * 
 * This is a simplified example. In production, use the Universal Router SDK
 * or carefully encode commands according to the Universal Router spec.
 */
function encodeV3SwapExactInput(params: {
  recipient: Address;
  amountIn: bigint;
  amountOutMin: bigint;
  path: Hex;
  payerIsUser: boolean;
}): { command: number; input: Hex } {
  // This is a conceptual example. Actual encoding is more complex.
  // See: https://docs.uniswap.org/contracts/universal-router/technical-reference
  throw new Error('Use Universal Router SDK for proper command encoding');
}

async function universalRouterSwap() {
  const walletClient = createWalletRpcClient(CHAIN_ID, PRIVATE_KEY);
  const publicClient = walletClient as any;
  const account = walletClient.account?.address;
  
  if (!account) {
    throw new Error('No account available');
  }

  const routerAddress = getUniswapUniversalRouter(CHAIN_ID);
  const tokenIn = getTokenMetadata(CHAIN_ID, 'USDC');
  const tokenOut = getTokenMetadata(CHAIN_ID, 'WETH');
  const amountIn = parseTokenAmount('1000', tokenIn.decimals);
  const deadline = BigInt(Math.floor(Date.now() / 1000) + 600);

  console.log(`Universal Router swap: ${amountIn} ${tokenIn.symbol} -> ${tokenOut.symbol}`);
  console.log(`Router: ${routerAddress}`);
  console.log(`Account: ${account}`);

  // Note: Universal Router command encoding is complex.
  // In production, use:
  // 1. Universal Router SDK (when available)
  // 2. Or carefully encode commands according to the spec
  // 3. Or use Protocolink which handles Universal Router integration

  console.log('\n⚠️  This is a conceptual example.');
  console.log('In production, use:');
  console.log('  1. Universal Router SDK for command encoding');
  console.log('  2. Or use Protocolink which integrates Universal Router');
  console.log('  3. Or carefully follow the Universal Router spec:');
  console.log('     https://docs.uniswap.org/contracts/universal-router/technical-reference');
  
  // Example flow:
  // 1. Create Permit2 signature (see uniswap-permit2.ts)
  // 2. Encode Universal Router commands
  // 3. Execute via Universal Router.execute()
  // 4. Universal Router will:
  //    - Use Permit2 to transfer tokens
  //    - Execute swap
  //    - Send output to recipient
  //    - All in one transaction
}

// Run if executed directly
if (import.meta.url === `file://${process.argv[1]}`) {
  universalRouterSwap().catch(console.error);
}

export { universalRouterSwap, COMMANDS };