/**
 * balances.js
 *
 * Reads on-chain balances. Requires the user to configure RPC endpoints
 * (config.json) — we don't bake in a paid provider's API key. Free public
 * endpoints are set as defaults so it works out of the box, but they are
 * rate-limited and not meant for production use.
 */

const { ethers } = require('ethers');
const { Connection, PublicKey, LAMPORTS_PER_SOL } = require('@solana/web3.js');

async function getEthBalance(address, rpcUrl) {
  const provider = new ethers.JsonRpcProvider(rpcUrl);
  const wei = await provider.getBalance(address);
  return ethers.formatEther(wei); // returns a decimal string, e.g. "1.234"
}

async function getSolBalance(address, rpcUrl) {
  const connection = new Connection(rpcUrl);
  const lamports = await connection.getBalance(new PublicKey(address));
  return (lamports / LAMPORTS_PER_SOL).toString();
}

/** Bitcoin: no JSON-RPC by default without running your own node, so we
 * use a block explorer's public REST API (Blockstream) instead. */
async function getBtcBalance(address, apiBase = 'https://blockstream.info/api') {
  const res = await fetch(`${apiBase}/address/${address}`);
  if (!res.ok) throw new Error(`Blockstream API error: ${res.status}`);
  const data = await res.json();
  const sats =
    data.chain_stats.funded_txo_sum -
    data.chain_stats.spent_txo_sum +
    data.mempool_stats.funded_txo_sum -
    data.mempool_stats.spent_txo_sum;
  return (sats / 1e8).toString();
}

module.exports = { getEthBalance, getSolBalance, getBtcBalance };