#!/usr/bin/env node
/**
 * chipnet-asm-multi-reservoir.mjs — one backed asset (ONE category), K reservoir
 * shards, with auto-assignment. The throughput layer on top of the sequencer.
 *
 * Setup: genesis ONE category whose supply is split across K reservoir UTXOs
 * (K minting-NFT shards), all at the same contract address. The claim() covenant
 * is per-UTXO, so each shard is independently claimable — same asset, one listing.
 *
 * Serve: N swap requests arrive; the auto-assigner hands each the next FREE shard.
 * Up to K requests broadcast TRULY IN PARALLEL (different reservoir coins + their
 * own funding → no shared input → no collision). Overflow (N>K) chains within its
 * shard (the per-shard sequencer). Result: K settlements per round instead of 1.
 *
 * Users fund their OWN claim here (each provides its BCH input + signs it), so a
 * round is genuinely parallel with nothing shared. Chipnet only.
 */
import { readFileSync } from 'node:fs';
import { join } from 'node:path';
import { TestNetWallet } from 'mainnet-js';
import { Contract, ElectrumNetworkProvider, TransactionBuilder, SignatureTemplate } from 'cashscript';

const ROOT = join(import.meta.dirname, '..');
const ARTIFACT = JSON.parse(readFileSync(join(ROOT, 'contracts/dist/DeviantOpenMintFT.json'), 'utf8'));
const K = Number(process.env.K ?? '3');                 // reservoir shards
const USERS = (process.env.USERS ?? 'c,e,f,g,b,d').split(',').map((s) => s.trim().toLowerCase());
const FUNDER = (process.env.FUNDER ?? 'd').toLowerCase(); // genesis funder + founder
const RATE = 1000n, FEE_BPS = 100n, MINER = 3000n, AMOUNT = 60n;
const PER_SHARD_SUPPLY = 1_000_000_000n;

const KEY = (w) => join(ROOT, w === 'a' ? '.chipnet-keys.json' : `.chipnet-keys-${w}.json`);
const hexToBin = (h) => { const o = new Uint8Array(h.length / 2); for (let i = 0; i < o.length; i++) o[i] = parseInt(h.slice(i * 2, i * 2 + 2), 16); return o; };
const binToHex = (b) => Array.from(b, (x) => x.toString(16).padStart(2, '0')).join('');
const rev = (h) => { const d = hexToBin(h); const o = new Uint8Array(d.length); for (let i = 0; i < d.length; i++) o[i] = d[d.length - 1 - i]; return o; };
const p2 = (pkh) => { const o = new Uint8Array(25); o[0] = 0x76; o[1] = 0xa9; o[2] = 0x14; o.set(pkh, 3); o[23] = 0x88; o[24] = 0xac; return o; };
const sleep = (ms) => new Promise((r) => setTimeout(r, ms));

async function main() {
  const provider = new ElectrumNetworkProvider('chipnet');
  const { wif } = JSON.parse(readFileSync(KEY(FUNDER), 'utf8'));
  const funder = await TestNetWallet.fromWIF(wif);
  const funderSig = new SignatureTemplate(funder.privateKey);
  const funderLB = p2(funder.publicKeyHash);

  // ── SETUP: genesis ONE category split across K reservoir shards ──
  console.log(`\n── SETUP: genesis 1 category → ${K} reservoir shards ──`);
  // 1) self-send to guarantee a vout=0, token-free UTXO (genesis must spend vout=0).
  const ss = await funder.send([{ cashaddr: funder.cashaddr, value: 40000, unit: 'sat' }]);
  const ssTxid = ss?.txId ?? ss?.txid;
  const category = ssTxid;                     // CHIP-2022-02: category = input[0] prevout txid (vout 0)
  await sleep(1500);
  const contract = new Contract(ARTIFACT, [rev(category), RATE, FEE_BPS, funderLB], { provider });
  console.log(`  category ${category.slice(0, 16)}…  contract ${contract.tokenAddress.slice(0, 24)}…`);

  const genIn = { txid: ssTxid, vout: 0, satoshis: 40000n };
  const genChange = 40000n - BigInt(K) * 1000n - 1500n;
  const gtb = new TransactionBuilder({ provider });
  gtb.addInput(genIn, funderSig.unlockP2PKH());
  for (let k = 0; k < K; k++) {
    gtb.addOutput({ to: contract.tokenAddress, amount: 1000n, token: { amount: PER_SHARD_SUPPLY, category, nft: { capability: 'minting', commitment: '' } } });
  }
  gtb.addOutput({ to: funder.cashaddr, amount: genChange });
  const gsent = await gtb.send();
  const genTxid = typeof gsent === 'string' ? gsent : gsent?.txid ?? gsent?.txId;
  console.log(`  genesis ${genTxid.slice(0, 16)}…  → ${K} shards of ${PER_SHARD_SUPPLY} each`);

  // Derive the K shard reservoir UTXOs locally (outputs 0..K-1 of the genesis tx).
  const shards = [];
  for (let k = 0; k < K; k++) {
    shards.push({ id: k, remaining: PER_SHARD_SUPPLY, reservoir: { txid: genTxid, vout: k, satoshis: 1000n, token: { amount: PER_SHARD_SUPPLY, category, nft: { capability: 'minting', commitment: '' } } } });
    console.log(`    shard ${k}: ${genTxid.slice(0, 10)}…:${k}`);
  }
  await sleep(2000);

  // ── SERVE: N requests, auto-assigned across shards, K in parallel per round ──
  const users = [];
  for (const u of USERS) {
    const { wif: w } = JSON.parse(readFileSync(KEY(u), 'utf8'));
    const wal = await TestNetWallet.fromWIF(w);
    users.push({ label: u.toUpperCase(), wal, sig: new SignatureTemplate(wal.privateKey), lb: p2(wal.publicKeyHash), tokenaddr: wal.tokenaddr, cashaddr: wal.cashaddr });
  }
  const gross = AMOUNT * RATE, fee = (gross * FEE_BPS) / 10_000n;

  console.log(`\n── SERVE: ${users.length} requests arrive at once → auto-assign to ${K} shards ──`);
  console.log(`(single reservoir would settle 1 per round; ${K} shards settle up to ${K} per round, in parallel)\n`);

  // pre-fetch each user's funding UTXO (their own BCH)
  for (const u of users) {
    u.bch = (await provider.getUtxos(u.cashaddr)).filter((x) => !x.token).sort((a, b) => Number(b.satoshis) - Number(a.satoshis))[0];
  }

  const rounds = Math.ceil(users.length / K);
  const settled = [];
  for (let r = 0; r < rounds; r++) {
    const batch = users.slice(r * K, r * K + K).map((u, j) => ({ u, shard: shards[j] })); // auto-assign: request → next free shard
    const t0 = Date.now();
    console.log(`round ${r + 1}: [${batch.map((b) => `${b.u.label}→shard${b.shard.id}`).join(', ')}]  (broadcast in parallel)`);
    const res = await Promise.all(batch.map(async ({ u, shard }) => {
      const at = Date.now() - t0;
      try {
        const change = 1000n + BigInt(u.bch.satoshis) - 1000n - gross - fee - MINER;
        if (change < 546n) throw new Error('user out of BCH');
        const newRemaining = shard.remaining - AMOUNT;
        const tb = new TransactionBuilder({ provider });
        tb.addInput(shard.reservoir, contract.unlock.claim(AMOUNT, u.lb));
        tb.addInput(u.bch, u.sig.unlockP2PKH());
        tb.addOutput({ to: contract.tokenAddress, amount: 1000n, token: { amount: newRemaining, category, nft: { capability: 'minting', commitment: '' } } });
        tb.addOutput({ to: u.tokenaddr, amount: gross, token: { amount: AMOUNT, category } });
        tb.addOutput({ to: funder.cashaddr, amount: fee });
        tb.addOutput({ to: u.cashaddr, amount: change });
        const spent = `${shard.reservoir.txid.slice(0, 10)}…:${shard.reservoir.vout}`;
        const sent = await tb.send();
        const txid = typeof sent === 'string' ? sent : sent?.txid ?? sent?.txId;
        // advance this shard + this user's funding for any later round
        shard.reservoir = { txid, vout: 0, satoshis: 1000n, token: { amount: newRemaining, category, nft: { capability: 'minting', commitment: '' } } };
        shard.remaining = newRemaining;
        u.bch = { txid, vout: 3, satoshis: change };
        return { label: u.label, shard: shard.id, at, txid, spent, err: null };
      } catch (e) {
        return { label: u.label, shard: shard.id, at, txid: null, err: (e?.message ?? String(e)).replace(/\s+/g, ' ').slice(0, 100) };
      }
    }));
    res.forEach((x) => console.log(`   ${x.label} shard${x.shard} +${x.at}ms  spent ${x.spent ?? '—'}  ${x.txid ? '✓ ' + x.txid.slice(0, 16) + '…' : '✗ ' + x.err}`));
    settled.push(...res);
    await sleep(1500);
  }

  const ok = settled.filter((x) => x.txid).length;
  const conflicts = settled.filter((x) => x.err?.includes('mempool-conflict')).length;
  console.log(`\n=== MULTI-RESERVOIR RESULT ===`);
  console.log(`  ${ok}/${settled.length} requests settled across ${K} shards of ONE category — ${conflicts} collisions.`);
  console.log(`  Up to ${K} settled truly in parallel per round (different shard coins + own funding).`);
  console.log(`  Throughput = K shards × ~250 chain-depth per block. Auto-assign spreads load; a new`);
  console.log(`  user is handed the next free shard, so simultaneous swaps never fight over one coin.`);
}
main().then(() => process.exit(0)).catch((e) => { console.error('ERROR:', e?.message ?? e); if (e?.stack) console.error(e.stack.split('\n').slice(0, 3).join('\n')); process.exit(1); });