// Token holders: holder count and concentration for a Solana token. Zero dependencies.
import { pathToFileURL } from "node:url";

const JUP = "https://lite-api.jup.ag";
const MINT_RE = /^[1-9A-HJ-NP-Za-km-z]{32,44}$/;
const num = (v) => (v === null || v === undefined || !Number.isFinite(Number(v)) ? null : Number(v));

async function rpc(url, method, params) {
  const res = await fetch(url, {
    method: "POST",
    headers: { "content-type": "application/json" },
    body: JSON.stringify({ jsonrpc: "2.0", id: 1, method, params }),
  });
  const body = await res.json().catch(() => null);
  if (!res.ok || body?.error) throw new Error(body?.error?.message ?? `RPC answered ${res.status}`);
  return body.result;
}

async function largestAccounts(rpcUrl, mint, supply) {
  const largest = await rpc(rpcUrl, "getTokenLargestAccounts", [mint]);
  const accounts = (largest?.value ?? []).slice(0, 20);
  const infos = await rpc(rpcUrl, "getMultipleAccounts", [accounts.map((a) => a.address), { encoding: "jsonParsed" }]);
  return accounts.map((a, i) => {
    const amount = num(a.uiAmountString ?? a.uiAmount);
    return {
      rank: i + 1,
      tokenAccount: a.address,
      owner: infos?.value?.[i]?.data?.parsed?.info?.owner ?? null,
      amount,
      pctOfSupply: supply && amount !== null ? (amount / supply) * 100 : null,
    };
  });
}

export async function holders(mint, { rpcUrl = process.env.SOLANA_RPC_URL } = {}) {
  if (!MINT_RE.test(String(mint ?? ""))) throw new Error("Usage: holders.mjs <mint address>");
  const res = await fetch(`${JUP}/tokens/v2/search?query=${mint}`, { headers: { accept: "application/json" } });
  if (!res.ok) throw new Error(`Jupiter answered ${res.status}`);
  const list = await res.json();
  const t = (Array.isArray(list) ? list : []).find((x) => x?.id === mint);
  if (!t) throw new Error(`Jupiter has no data for mint ${mint}`);

  let largest = null;
  let largestError = null;
  if (rpcUrl) {
    try {
      largest = await largestAccounts(rpcUrl, mint, num(t.totalSupply));
    } catch (e) {
      largestError = String(e?.message ?? e);
    }
  }
  return {
    source: rpcUrl ? "jupiter + your RPC" : "jupiter",
    fetchedAt: new Date().toISOString(),
    mint,
    symbol: t.symbol ?? null,
    name: t.name ?? null,
    holderCount: num(t.holderCount),
    holderChange24hPct: num(t.stats24h?.holderChange),
    topHoldersPct: num(t.audit?.topHoldersPercentage),
    devMints: num(t.audit?.devMints),
    mintAuthorityDisabled: t.audit?.mintAuthorityDisabled ?? null,
    freezeAuthorityDisabled: t.audit?.freezeAuthorityDisabled ?? null,
    organicScore: num(t.organicScore),
    isVerified: t.isVerified ?? null,
    totalSupply: num(t.totalSupply),
    largest,
    ...(largestError ? { largestError } : {}),
  };
}

if (process.argv[1] && import.meta.url === pathToFileURL(process.argv[1]).href) {
  holders(process.argv[2])
    .then((r) => console.log(JSON.stringify(r, null, 2)))
    .catch((e) => {
      console.log(JSON.stringify({ error: String(e?.message ?? e) }));
      process.exit(1);
    });
}