Events and finality

// index.mjs   (Node 18+, npm install viem)
// env: RPC_URL, HOOK_ADDRESS and GENESIS_BLOCK (after deployment)
import { createPublicClient, http, parseAbi } from "viem";

const { RPC_URL, HOOK_ADDRESS } = process.env;
const GENESIS_BLOCK = BigInt(process.env.GENESIS_BLOCK);
const CHUNK = 5000n;

export const geneEvents = parseAbi([
  "event Genesis(bytes32 indexed genomeHash, address token, bytes32 poolId)",
  "event Launched(bytes32 indexed poolId, int24 tickLower, int24 tickUpper, uint128 liquidity, uint256 geneSeeded, uint256 dustBurned)",
  "event EpochClosed(uint32 indexed epoch, (uint96 revenue, uint32 activeBlocks, uint32 pathTicks, uint88 ethCommitted, bool closed) record, int256 netGene, int24 maxTick, int24 minTick)",
  "event FlowBudgets(uint32 indexed epoch, uint256 bidBudget, uint256 immBudget, int24 pLowTick)",
  "event GeneTransition(uint8 indexed gene, uint8 from, uint8 to, uint32 indexed epoch, bytes32 evidenceHash)",
  "event FeesHarvested(uint256 eth, uint256 gene, uint256 positionsPoked)",
  "event MassAdded(uint8 indexed kind, int24 tickLower, int24 tickUpper, uint128 liquidity, uint256 amount, int24 spotTick, int24 anchorTick)",
  "event PlacementSkipped(uint8 indexed kind, int24 tickLower, int24 tickUpper, uint256 liquidity)",
  "event Regenerated(uint256 ethSpent, uint256 geneBurned, int24 spotTick, int24 limitTick)",
]);

const client = createPublicClient({ transport: http(RPC_URL) });

async function fetchLogs(from, to) {
  const out = [];
  for (let a = from; a <= to; a += CHUNK) {
    const b = a + CHUNK - 1n < to ? a + CHUNK - 1n : to;
    const logs = await client.getLogs({ address: HOOK_ADDRESS, events: geneEvents, fromBlock: a, toBlock: b, strict: true });
    out.push(...logs.filter((l) => l.address.toLowerCase() === HOOK_ADDRESS.toLowerCase()));
  }
  return out.sort((x, y) => (x.blockNumber === y.blockNumber ? x.logIndex - y.logIndex : x.blockNumber < y.blockNumber ? -1 : 1));
}

const finalLogs = [];
let finalTo = GENESIS_BLOCK - 1n;

export async function poll() {
  const finalized = (await client.getBlock({ blockTag: "finalized" })).number;
  const latest = await client.getBlockNumber();
  if (finalized > finalTo) {
    finalLogs.push(...(await fetchLogs(finalTo + 1n, finalized)));
    finalTo = finalized;
  }
  // replaced in full on every poll
  const window = latest > finalTo ? await fetchLogs(finalTo + 1n, latest) : [];
  return { finalLogs, window, finalized, latest };
}

const { finalLogs: f, window: w, finalized } = await poll();
console.log(`${f.length} finalized logs up to block ${finalized}; ${w.length} logs in the unfinalized window`);