Merge pull request 'fix: feat: RPC-only staking helpers for red-team agent (#518)' (#523) from fix/issue-518 into master

scripts/harb-evaluator/helpers/stake-rpc.ts

@@ -0,0 +1,253 @@
+/**
+ * RPC-only staking helpers for the red-team agent.
+ *
+ * No browser UI interaction required. Uses ethers + rpcCall directly
+ * (same pattern as market.ts and recenter.ts).
+ *
+ * Note: importing from swap.js would drag in Playwright via its top-level
+ * `import { expect } from '@playwright/test'`. This file avoids that import
+ * by inlining a receipt poller that returns the receipt object.
+ *
+ * stakeViaRpc         — approve KRK to Stake, call snatch() with empty positionsToSnatch
+ * unstakeViaRpc       — call exitPosition()
+ * getStakingPositions — scan PositionCreated events and filter active positions
+ * getStakingState     — read averageTaxRate and percentageStaked from the contract
+ */
+import { Interface, JsonRpcProvider, Wallet, ZeroAddress } from 'ethers';
+import { rpcCall } from './rpc.js';
+
+const STAKE_ABI = [
+  // taxRate param is the index into the TAX_RATES array (0-4), not a raw rate value
+  'function snatch(uint256 assets, address receiver, uint32 taxRate, uint256[] positionsToSnatch) returns (uint256 positionId)',
+  'function exitPosition(uint256 positionId)',
+  'function positions(uint256 positionId) view returns (uint256 share, address owner, uint32 creationTime, uint32 lastTaxTime, uint32 taxRate)',
+  'function getAverageTaxRate() view returns (uint256)',
+  'function getPercentageStaked() view returns (uint256)',
+  'event PositionCreated(uint256 indexed positionId, address indexed owner, uint256 kraikenDeposit, uint256 share, uint32 taxRate)',
+];
+
+const ERC20_ABI = ['function approve(address spender, uint256 amount) returns (bool)'];
+
+export interface StakeRpcConfig {
+  rpcUrl: string;
+  privateKey: string;
+  stakeAddress: string;
+  krkAddress: string;
+  amount: bigint;
+  taxRateIndex: number;
+}
+
+export interface UnstakeRpcConfig {
+  rpcUrl: string;
+  privateKey: string;
+  stakeAddress: string;
+  positionId: bigint;
+}
+
+export interface StakingPosition {
+  positionId: bigint;
+  share: bigint;
+  owner: string;
+  creationTime: number;
+  lastTaxTime: number;
+  taxRate: number;
+}
+
+export interface StakingState {
+  /** Weighted-average tax rate; 1e18 = maximum rate. */
+  averageTaxRate: bigint;
+  /** Fraction of authorised stake currently staked; 1e18 = 100%. */
+  percentageStaked: bigint;
+}
+
+// ── Internal helpers ──────────────────────────────────────────────────────────
+
+const stakeIface = new Interface(STAKE_ABI);
+const erc20Iface = new Interface(ERC20_ABI);
+
+type ReceiptLog = { address: string; topics: string[]; data: string };
+type TxReceipt = { status: string; logs: ReceiptLog[] };
+
+/**
+ * Poll eth_getTransactionReceipt until the transaction is mined.
+ * Returns the receipt so callers can parse logs without a second round-trip.
+ * Throws if the transaction reverts (status 0x0) or times out.
+ */
+async function pollReceipt(rpcUrl: string, txHash: string, maxAttempts = 20): Promise<TxReceipt> {
+  for (let i = 0; i < maxAttempts; i++) {
+    const receipt = (await rpcCall(rpcUrl, 'eth_getTransactionReceipt', [txHash])) as TxReceipt | null;
+    if (receipt !== null) {
+      if (receipt.status === '0x0') throw new Error(`Transaction ${txHash} reverted (status 0x0)`);
+      return receipt;
+    }
+    // eslint-disable-next-line no-restricted-syntax -- Polling with timeout: no push source for tx receipt over HTTP RPC. See AGENTS.md #Engineering Principles.
+    await new Promise(r => setTimeout(r, 500));
+  }
+  throw new Error(`Transaction ${txHash} not mined after ${maxAttempts * 500}ms`);
+}
+
+// ── Exported helpers ──────────────────────────────────────────────────────────
+
+/**
+ * Approve KRK to the Stake contract then call snatch() with an empty
+ * positionsToSnatch array, which is the simple-stake (non-snatching) path.
+ *
+ * @returns The new staking position ID.
+ */
+export async function stakeViaRpc(config: StakeRpcConfig): Promise<bigint> {
+  const provider = new JsonRpcProvider(config.rpcUrl);
+  const wallet = new Wallet(config.privateKey, provider);
+  const account = wallet.address;
+
+  // Step 1: approve KRK spend allowance to the Stake contract
+  console.log(`[stake-rpc] Approving ${config.amount} KRK to Stake contract...`);
+  const approveData = erc20Iface.encodeFunctionData('approve', [config.stakeAddress, config.amount]);
+  const approveTx = await wallet.sendTransaction({ to: config.krkAddress, data: approveData });
+  await pollReceipt(config.rpcUrl, approveTx.hash);
+  console.log('[stake-rpc] Approve mined');
+
+  // Step 2: call snatch() — empty positionsToSnatch = simple stake with no snatching
+  console.log(
+    `[stake-rpc] Calling snatch(${config.amount}, ${account}, taxRateIndex=${config.taxRateIndex}, [])...`,
+  );
+  const snatchData = stakeIface.encodeFunctionData('snatch', [
+    config.amount,
+    account,
+    config.taxRateIndex,
+    [],
+  ]);
+  const snatchTx = await wallet.sendTransaction({ to: config.stakeAddress, data: snatchData });
+  // pollReceipt returns the receipt directly — no second round-trip needed for log parsing
+  const receipt = await pollReceipt(config.rpcUrl, snatchTx.hash);
+  console.log(`[stake-rpc] Stake mined: ${snatchTx.hash}`);
+
+  provider.destroy();
+
+  // Parse positionId from the PositionCreated event in the receipt
+  const positionCreatedTopic = stakeIface.getEvent('PositionCreated')!.topicHash;
+  const log = receipt.logs.find(
+    l =>
+      l.address.toLowerCase() === config.stakeAddress.toLowerCase() &&
+      l.topics[0] === positionCreatedTopic,
+  );
+  if (!log) {
+    throw new Error('[stake-rpc] PositionCreated event not found in receipt');
+  }
+
+  const positionId = BigInt(log.topics[1]);
+  console.log(`[stake-rpc] ✅ Stake complete — positionId: ${positionId}`);
+  return positionId;
+}
+
+/**
+ * Call exitPosition() to unstake a position and return KRK to the owner.
+ * Pays the Harberger tax floor before returning assets.
+ */
+export async function unstakeViaRpc(config: UnstakeRpcConfig): Promise<void> {
+  const provider = new JsonRpcProvider(config.rpcUrl);
+  const wallet = new Wallet(config.privateKey, provider);
+
+  console.log(`[stake-rpc] Calling exitPosition(${config.positionId})...`);
+  const data = stakeIface.encodeFunctionData('exitPosition', [config.positionId]);
+  const tx = await wallet.sendTransaction({ to: config.stakeAddress, data });
+  await pollReceipt(config.rpcUrl, tx.hash);
+  console.log(`[stake-rpc] ✅ Unstake mined: ${tx.hash}`);
+
+  provider.destroy();
+}
+
+/**
+ * Return all active staking positions for `account`.
+ *
+ * Discovers positions by scanning PositionCreated events filtered by owner,
+ * then confirms each one is still active (non-zero share / non-zero owner)
+ * by reading the positions() mapping directly.
+ *
+ * Note: fromBlock '0x0' scans from genesis — acceptable for local Anvil;
+ * would need a deploy-block offset for use against a live node.
+ */
+export async function getStakingPositions(config: {
+  rpcUrl: string;
+  stakeAddress: string;
+  account: string;
+}): Promise<StakingPosition[]> {
+  const positionCreatedTopic = stakeIface.getEvent('PositionCreated')!.topicHash;
+  const ownerPadded = '0x' + config.account.slice(2).padStart(64, '0');
+
+  const logs = (await rpcCall(config.rpcUrl, 'eth_getLogs', [
+    {
+      address: config.stakeAddress,
+      topics: [positionCreatedTopic, null, ownerPadded],
+      fromBlock: '0x0',
+      toBlock: 'latest',
+    },
+  ])) as Array<{ topics: string[]; data: string }>;
+
+  const active: StakingPosition[] = [];
+
+  for (const log of logs) {
+    const positionId = BigInt(log.topics[1]);
+
+    // Read the live position state from the mapping
+    const raw = (await rpcCall(config.rpcUrl, 'eth_call', [
+      {
+        to: config.stakeAddress,
+        data: stakeIface.encodeFunctionData('positions', [positionId]),
+      },
+      'latest',
+    ])) as string;
+
+    const decoded = stakeIface.decodeFunctionResult('positions', raw);
+    const share = BigInt(decoded[0]);
+    const owner = decoded[1] as string;
+
+    // Exited positions have owner reset to zero address
+    if (owner.toLowerCase() !== ZeroAddress && share > 0n) {
+      active.push({
+        positionId,
+        share,
+        owner,
+        creationTime: Number(decoded[2]),
+        lastTaxTime: Number(decoded[3]),
+        taxRate: Number(decoded[4]),
+      });
+    }
+  }
+
+  console.log(`[stake-rpc] ${active.length} active position(s) for ${config.account}`);
+  return active;
+}
+
+/**
+ * Read the current global staking state from the Stake contract.
+ *
+ * @returns averageTaxRate — weighted-average Harberger tax rate (1e18 = max)
+ * @returns percentageStaked — fraction of authorised supply currently staked (1e18 = 100%)
+ */
+export async function getStakingState(config: {
+  rpcUrl: string;
+  stakeAddress: string;
+}): Promise<StakingState> {
+  const [avgRateRaw, pctStakedRaw] = (await Promise.all([
+    rpcCall(config.rpcUrl, 'eth_call', [
+      {
+        to: config.stakeAddress,
+        data: stakeIface.encodeFunctionData('getAverageTaxRate', []),
+      },
+      'latest',
+    ]),
+    rpcCall(config.rpcUrl, 'eth_call', [
+      {
+        to: config.stakeAddress,
+        data: stakeIface.encodeFunctionData('getPercentageStaked', []),
+      },
+      'latest',
+    ]),
+  ])) as [string, string];
+
+  const averageTaxRate = BigInt(avgRateRaw);
+  const percentageStaked = BigInt(pctStakedRaw);
+
+  console.log(`[stake-rpc] averageTaxRate=${averageTaxRate} percentageStaked=${percentageStaked}`);
+  return { averageTaxRate, percentageStaked };
+}