refactor nwc

1 files changed, 117 insertions, 0 deletions

diff --git a/lib/nwc.ts b/lib/nwc.ts
new file mode 100644
index 00000000..d8323495
--- /dev/null
+++ b/lib/nwc.ts
@@ -0,0 +1,117 @@
+import config from "$config";
+import { err } from "$lib/logging";
+import { g } from "$lib/db";
+import { Relay } from "nostr";
+import { getInvoice, sleep } from "$lib/utils";
+import { sendInternal, sendLightning } from "$lib/payments";
+import { serverPubkey } from "$lib/nostr";
+import { nip04, nip19, finalizeEvent } from "nostr-tools";
+import type { UnsignedEvent } from "nostr-tools";
+import ln from "$lib/ln";
+
+let result = (result) => ({ result });
+let error = (error) => ({ error });
+
+export default () => {
+  let r = new Relay("ws://strfry:7777");
+
+  r.on("open", (_) => {
+    r.subscribe("nwc", { kinds: [23194], "#p": [serverPubkey] });
+  });
+
+  r.on("event", async (sub, ev) => {
+    try {
+      if (sub !== "nwc") return;
+      let { content, pubkey } = ev;
+      let sk = nip19.decode(config.nostrKey).data as Uint8Array;
+      let { params, method } = JSON.parse(
+        await nip04.decrypt(sk, pubkey, content),
+      );
+
+      let uid = await g(pubkey);
+      let user = await g(`user:${uid}`);
+
+      let result = await handle(method, params, user);
+      let payload = JSON.stringify({ result_type: method, result });
+      content = await nip04.encrypt(sk, pubkey, payload);
+
+      let response: UnsignedEvent = {
+        created_at: Math.floor(Date.now() / 1000),
+        kind: 23195,
+        pubkey: serverPubkey,
+        tags: [
+          ["p", pubkey],
+          ["e", ev.id],
+        ],
+        content,
+      };
+
+      response = await finalizeEvent(response, sk);
+      r.send(["EVENT", response]);
+    } catch (e) {
+      err("problem with nwc", e.message);
+    }
+  });
+};
+
+let handle = (method, params, user) =>
+  ({
+    async pay_invoice() {
+      let { invoice: pr } = params;
+      let { amount_msat, payee } = await ln.decode(pr);
+      let { id } = await ln.getinfo();
+      let amount = Math.round(amount_msat / 1000);
+
+      if (payee === id) {
+        let invoice = await getInvoice(pr);
+        let recipient = await g(`user:${invoice.uid}`);
+
+        let { id: preimage } = await sendInternal({
+          amount,
+          invoice,
+          recipient,
+          sender: user,
+        });
+
+        return result({ preimage });
+      } else {
+        await sendLightning({
+          amount,
+          user,
+          pr,
+          maxfee: 50,
+        });
+
+        for (let i = 0; i < 10; i++) {
+          let { pays } = await ln.listpays(pr);
+          let p = pays.find((p) => p.status === "complete");
+          if (p) {
+            let { preimage } = p;
+            return result({ preimage });
+          }
+          await sleep(2000);
+        }
+
+        return error({ code: "INTERNAL", message: "Payment timed out" });
+      }
+    },
+
+    async get_info() {
+      let { alias, blockheight, color } = await ln.getinfo();
+      return {
+        result: {
+          alias,
+          color,
+          pubkey: serverPubkey,
+          network: "mainnet",
+          block_height: blockheight,
+          methods: ["pay_invoice", "get_balance", "get_info"],
+        },
+      };
+    },
+
+    async get_balance() {
+      let balance = await g(`balance:${user.id}`);
+      return result({ balance });
+    },
+  })[method](params);