#!/usr/bin/env node
// Dry Run DR1 verifier. Zero dependencies (Node 18+). Checks one paper record row against its daily
// Merkle root and the root's memo on Solana, without trusting dryrun.space for anything but the data.
//
//   node verify.mjs <row id> [--api https://dryrun.space] [--rpc https://api.mainnet-beta.solana.com]
//   node verify.mjs --vectors        (offline: the published test vectors)
import { createHash } from "node:crypto";

const NODE = Buffer.from("DR1/node");
const MEMO_RE = /^dr1:root:(\d{4}-\d{2}-\d{2}):([0-9a-f]{64}):(\d+)$/;
const sha = (...parts) => createHash("sha256").update(Buffer.concat(parts.map((p) => (typeof p === "string" ? Buffer.from(p, "utf8") : p)))).digest();

/** Canonical JSON: keys sorted, no whitespace. Leaf values are strings and integers only. */
function canonical(v) {
  if (v === null || typeof v !== "object") return JSON.stringify(v);
  if (Array.isArray(v)) return `[${v.map(canonical).join(",")}]`;
  return `{${Object.keys(v).sort().map((k) => `${JSON.stringify(k)}:${canonical(v[k])}`).join(",")}}`;
}

function node(a, b) {
  return Buffer.compare(a, b) <= 0 ? sha(NODE, a, b) : sha(NODE, b, a);
}

function fold(leaf, proof) {
  let h = leaf;
  for (const s of proof) h = node(h, Buffer.from(s, "hex"));
  return h.toString("hex");
}

function rootOf(hashes) {
  let level = hashes;
  while (level.length > 1) {
    const next = [];
    for (let i = 0; i < level.length; i += 2) next.push(node(level[i], level[i + 1] ?? level[i]));
    level = next;
  }
  return level[0].toString("hex");
}

const VECTORS = [
  "{\"candle_t\":1789999800,\"dsl_hash\":\"9f2c2a1b4bd3c0d4ffb2b4d3a7c1e0f5b6a9d8c7e6f5a4b3c2d1e0f9a8b7c6d5\",\"equity_usd\":\"100\",\"fee_usd\":\"0\",\"kind\":\"signal\",\"network_usd\":\"0\",\"pct\":\"0\",\"price\":\"0.00214\",\"reason\":\"rule\",\"recorded_at\":1790000160,\"rule\":1,\"seq\":1,\"side\":\"buy\",\"slippage_usd\":\"0\",\"spec\":\"dr1\",\"strategy_id\":\"s_vector2345\",\"t\":1790000100,\"tokens\":\"0\",\"usd\":\"25\",\"version\":1}",
  "{\"candle_t\":1790000100,\"dsl_hash\":\"9f2c2a1b4bd3c0d4ffb2b4d3a7c1e0f5b6a9d8c7e6f5a4b3c2d1e0f9a8b7c6d5\",\"equity_usd\":\"99.9124271488\",\"fee_usd\":\"0.06245\",\"kind\":\"fill\",\"network_usd\":\"0.02\",\"pct\":\"0\",\"price\":\"0.00213\",\"reason\":\"rule\",\"recorded_at\":1790000460,\"rule\":1,\"seq\":2,\"side\":\"buy\",\"slippage_usd\":\"0.0031228512\",\"spec\":\"dr1\",\"strategy_id\":\"s_vector2345\",\"t\":1790000100,\"tokens\":\"11695.9230932\",\"usd\":\"25\",\"version\":1}",
  "{\"candle_t\":1790003400,\"dsl_hash\":\"9f2c2a1b4bd3c0d4ffb2b4d3a7c1e0f5b6a9d8c7e6f5a4b3c2d1e0f9a8b7c6d5\",\"equity_usd\":\"104.356\",\"fee_usd\":\"0\",\"kind\":\"signal\",\"network_usd\":\"0\",\"pct\":\"100\",\"price\":\"0.00251\",\"reason\":\"take_profit\",\"recorded_at\":1790003760,\"rule\":0,\"seq\":3,\"side\":\"sell\",\"slippage_usd\":\"0\",\"spec\":\"dr1\",\"strategy_id\":\"s_vector2345\",\"t\":1790003700,\"tokens\":\"0\",\"usd\":\"0\",\"version\":1}"
];
const VECTOR_ROOT = "fd5ef3e1c89d1da3d0cb6ff1f0fedc4671d185bc33fbb578fa74b8ccf5a5a6aa";
const EMPTY_ROOT = "356b7d2552be077122a90f18acde60e021624bf900e05da361af9665d61ae8da";

function check(ok, text) {
  console.log(`${ok ? "✓" : "✗"} ${text}`);
  if (!ok) process.exitCode = 1;
  return ok;
}

async function vectors() {
  const hashes = VECTORS.map((j) => sha(j));
  VECTORS.forEach((j, i) => check(canonical(JSON.parse(j)) === j, `vector ${i} is canonical; sha256 ${hashes[i].toString("hex")}`));
  check(rootOf(hashes) === VECTOR_ROOT, `root ${rootOf(hashes)}`);
  check(sha("DR1/empty").toString("hex") === EMPTY_ROOT, `empty root ${EMPTY_ROOT}`);
}

async function main() {
  const args = process.argv.slice(2);
  if (args.includes("--vectors")) return vectors();
  const opt = (k, d) => (args.includes(k) ? args[args.indexOf(k) + 1] : d);
  const id = args.find((a) => /^\d+$/.test(a));
  if (!id) return console.log("usage: node verify.mjs <row id> [--api URL] [--rpc URL] | --vectors");
  const api = opt("--api", "https://dryrun.space");
  const rpc = opt("--rpc", "https://api.mainnet-beta.solana.com");
  const p = await (await fetch(`${api}/api/v1/proof/${id}`)).json();
  if (p.error) return check(false, p.error);
  console.log(`row #${p.signal_id}, ${p.date} UTC, leaf ${p.leaf_index + 1}/${p.leaf_count}\n${p.leaf_json}`);
  check(canonical(JSON.parse(p.leaf_json)) === p.leaf_json, "row is canonical JSON");
  const leaf = sha(p.leaf_json);
  check(leaf.toString("hex") === p.leaf_hash, `sha256(row) = ${leaf.toString("hex")}`);
  const root = fold(leaf, p.proof);
  check(root === p.root, `proof folds to root ${root}`);
  if (!p.root_tx) return console.log(`… root not published on chain yet (${p.status})`);
  const tx = await (await fetch(rpc, { method: "POST", headers: { "content-type": "application/json" }, body: JSON.stringify({ jsonrpc: "2.0", id: 1, method: "getTransaction", params: [p.root_tx.signature, { encoding: "jsonParsed", maxSupportedTransactionVersion: 0, commitment: "confirmed" }] }) })).json();
  const memos = (tx.result?.transaction?.message?.instructions ?? []).filter((i) => i.program === "spl-memo").map((i) => i.parsed);
  const m = memos.map((x) => String(x).match(MEMO_RE)).find(Boolean);
  check(!!m && m[1] === p.date && m[2] === root && Number(m[3]) === p.leaf_count, `memo on chain: ${memos.join(" | ") || "none"} (tx ${p.root_tx.signature})`);
  const signer = tx.result?.transaction?.message?.accountKeys?.find((k) => k.signer)?.pubkey;
  console.log(`  signed by ${signer} (the oracle wallet published on dryrun.space/method)`);
}

main().catch((e) => {
  console.error(e);
  process.exitCode = 1;
});