lnurl pay requests

1 files changed, 115 insertions, 0 deletions

diff --git a/lib/send.js b/lib/send.js
new file mode 100644
index 00000000..2e04c5d4
--- /dev/null
+++ b/lib/send.js
@@ -0,0 +1,115 @@
+const bolt11 = require("bolt11");
+
+send = async (amount, hash, user) => {
+  let payreq = bolt11.decode(hash);
+
+  if (!amount) amount = payreq.satoshis;
+
+  l.info("attempting lightning payment", user.username, amount);
+
+  if (seen.includes(hash)) {
+    l.warn("attempted to pay a paid invoice", user.username);
+    throw new Error("Invoice has been paid, can't pay again");
+  }
+
+    await db.transaction(async (transaction) => {
+      let account = await db.Account.findOne({
+        where: {
+          user_id: user.id,
+          asset: config.liquid.btcasset,
+        },
+        lock: transaction.LOCK.UPDATE,
+        transaction,
+      });
+
+      if (account.balance < amount) {
+        throw new Error("Insufficient funds");
+      }
+
+      let error, fee, total, preimage;
+
+      if (config.lna.clightning) {
+        let m = await lna.pay(hash);
+        let sent;
+        ({
+          msatoshi: total,
+          msatoshi_sent: sent,
+          payment_preimage: preimage,
+        } = m);
+
+        fee = parseInt((sent - total) / 1000);
+        total = parseInt(total / 1000);
+      } else {
+        let m = await lna.sendPaymentSync({
+          amt: amount,
+          payment_request: hash,
+          max_parts: 10,
+        });
+
+        if (m.payment_error) throw new Error(m.payment_error);
+
+        ({
+          payment_route: { total_fees: fee, total_amt: total },
+          payment_preimage: preimage,
+        } = m);
+      }
+
+      preimage = preimage.toString("hex");
+
+      if (payreq.payeeNodeKey === config.lnb.id) {
+        if (config.lna.clightning) {
+          let invoice = await lna.invoice(
+            `${amount}sat` || "any",
+            new Date(),
+            "",
+            360
+          );
+          let { bolt11: payment_request } = invoice;
+          await lnb.pay(payment_request);
+        } else {
+          let invoice = await lna.addInvoice({ value: amount });
+          let { payment_request } = invoice;
+          await lnb.sendPaymentSync({ payment_request, max_parts: 10 });
+        }
+        l.info("lnb sent back", amount);
+      }
+
+      if (seen.includes(preimage)) {
+        l.warn("duplicate payment detected", preimage);
+        throw new Error("Duplicate payment detected");
+      }
+
+      total = parseInt(total);
+      fee = parseInt(fee);
+
+      account.balance -= total;
+      await account.save({ transaction });
+
+      let payment = await db.Payment.create(
+        {
+          amount: -total,
+          account_id: account.id,
+          user_id: user.id,
+          hash,
+          preimage,
+          rate: app.get("rates")[user.currency],
+          currency: user.currency,
+          confirmed: true,
+          network: "LNBTC",
+          fee,
+        },
+        { transaction }
+      );
+
+      payment = payment.get({ plain: true });
+      payment.account = account.get({ plain: true });
+
+      emit(user.username, "account", payment.account);
+      emit(user.username, "payment", payment);
+
+      seen.push(preimage);
+      seen.push(hash);
+
+      l.info("sent lightning", user.username, total);
+    });
+};