import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import {
  makePaymentAwareServerTransport,
  PhoenixdProvider,
  LoopLedger,
} from "@loop-xxi/loop-mcp";

const server = new McpServer({ name: "my-server", version: "1.0.0" });
server.tool("get-quote", "Premium market data", { /* schema */ }, async () => ({
  content: [{ type: "text", text: "..." }],
}));

const transport = makePaymentAwareServerTransport(
  "0xYourReceivingAddress",            // x402 / USDC payouts
  { "get-quote": "$0.01" },            // per-tool USD price
  {
    network: "base",
    ledger: new LoopLedger(),
    // The addition — enable the Lightning / L402 rail:
    lightning: {
      provider: new PhoenixdProvider(process.env.PHOENIXD_URL!, process.env.PHOENIXD_PASSWORD!),
      l402Secret: process.env.L402_SECRET!,
      btcUsdPrice: 65000,              // live spot, injected
    },
  }
);

await server.connect(transport);

import { Client } from "@modelcontextprotocol/sdk/client/index.js";
import { makePaymentAwareClientTransport } from "@loop-xxi/loop-mcp";

const transport = makePaymentAwareClientTransport(serverUrl, wallet, {
  preferredRail: "l402",               // or "x402"
  lightningPayer,                      // pays the invoice, returns the preimage
  paymentCallback: (proof, rail) => console.log(`paid via ${rail}: ${proof}`),
});

const client = new Client({ name: "agent", version: "1.0.0" }, { capabilities: {} });
await client.connect(transport);       // tool calls now pay automatically

TARGET_URL=https://server/mcp PRIVATE_KEY=0x... RAIL=l402 npx loop-mcp client-proxy

node scripts/demo-core.mjs
# ✅ valid preimage verifies
# ✅ forged preimage rejected
# ✅ cross-tool replay rejected
# ✅ wrong-secret macaroon rejected
# ✅ x402 atomic amount = 2000
# ✅ canonical rows = 2 (internal excluded)
# ✅ canonical USD roll-up = 0.003
# === 7 passed, 0 failed ===

src/
  server.ts            LoopDualRailServerTransport (x402 port + L402 addition)
  client.ts            dual-rail client transport
  rails/x402.ts        USDC/x402 helpers (dependency-free)
  rails/l402.ts        L402 macaroon + preimage verification (dependency-free)
  lightning/provider.ts MockLightningProvider + PhoenixdProvider
  pricing/satsQuote.ts  USD→sats with 21% BTC discount ≤ $100
  ledger.ts            canonical rail-tagged ledger
  proxy/index.ts       client & server proxies
example/               dual-rail "todo" MCP server + client
scripts/demo-core.mjs  zero-dependency end-to-end proof of the payment core
test/core.test.ts      unit tests

ENDPOINT="https://mcp.loopxxi.com/mcp"
BODY='{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"btc_price","arguments":{}}}'

# 1. Challenge — expect HTTP 402 with an invoice.
RESP=$(curl -s -w "\n%{http_code}" -X POST "$ENDPOINT" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -d "$BODY")
HTTP_CODE=$(echo "$RESP" | tail -1)
BODY_JSON=$(echo "$RESP" | sed '$d')

# 2. Extract the token + BOLT11 invoice from the 402 body.
TOKEN=$(echo "$BODY_JSON" | grep -o '"token":"[^"]*"' | head -1 | cut -d'"' -f4)
INVOICE=$(echo "$BODY_JSON" | grep -o '"payment_request":"[^"]*"' | head -1 | cut -d'"' -f4)

# 3. Pay the invoice with any Lightning wallet, then retry with the L402 header.
#    (replace <PREIMAGE> with the 64-char hex preimage your wallet returns)
curl -s -X POST "$ENDPOINT" \
  -H "Content-Type: application/json" \
  -H "Accept: application/json, text/event-stream" \
  -H "Authorization: L402 ${TOKEN}:<PREIMAGE>" \
  -d "$BODY"

const ENDPOINT = "https://mcp.loopxxi.com/mcp";
const callTool = {
  jsonrpc: "2.0", id: 1, method: "tools/call",
  params: { name: "btc_price", arguments: {} },
};

// Replace with your Lightning wallet — must return the 64-char hex preimage.
async function payBolt11(invoice) { throw new Error("implement payBolt11"); }

// 1. Challenge → 402.
const res1 = await fetch(ENDPOINT, {
  method: "POST",
  headers: { "Content-Type": "application/json", "Accept": "application/json, text/event-stream" },
  body: JSON.stringify(callTool),
});
const { token, payment_request } = (await res1.json()).error;

// 2. Pay the invoice, get the preimage.
const preimage = await payBolt11(payment_request);

// 3. Retry with Authorization: L402 <token>:<preimage> (split on the LAST colon).
const res2 = await fetch(ENDPOINT, {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
    "Accept": "application/json, text/event-stream",
    "Authorization": "L402 " + token + ":" + preimage,
  },
  body: JSON.stringify(callTool),
});
console.log(await res2.json());

# Buy a $10 pack → get a loop_<credit_key> (1000 credits → sats at live BTC price)
curl -s -X POST https://api.loopxxi.com/v1/credits/checkout \
  -H "Content-Type: application/json" -d '{"pack":"p10"}'
# → {"credit_key":"loop_...","checkout_url":"https://buy.stripe.com/..."}
# Complete payment on the Stripe page, then:

curl -s -X POST https://mcp.loopxxi.com/mcp \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer loop_<credit_key>" \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"btc_price","arguments":{}}}'

                          ┌──────────────── 402 Payment Required ───────────────┐
   agent / MCP client ───▶│  accepts: [ x402 (USDC on Base),  l402 (Lightning) ] │
                          └──────────────────────────────────────────────────────┘
                                   │                              │
                pay USDC + retry   │                              │  pay invoice + retry
              (X-PAYMENT header)   ▼                              ▼  (Authorization: L402 mac:preimage)
                          ┌─────────────────────────────────────────────┐
                          │      LoopDualRailServerTransport             │
                          │  verify ─▶ run tool ─▶ settle ─▶ LoopLedger  │
                          └─────────────────────────────────────────────┘
                                   │  rail-tagged rows (x402 | l402)
                                   ▼
                            canonical revenue (net sats north-star)

npm install @loop-xxi/loop-mcp
# peer dependency
npm install @modelcontextprotocol/sdk