refactor: extract wallet system

packages/wallet/src/Cashu.ts

@@ -0,0 +1,104 @@
+import { CashuMint, Proof } from "@cashu/cashu-ts";
+
+import { InvoiceRequest, LNWallet, WalletEvents, WalletInfo, WalletInvoice } from ".";
+import EventEmitter from "eventemitter3";
+
+export type CashuWalletConfig = {
+  url: string;
+  keys: Record<string, string>;
+  keysets: Array<string>;
+  proofs: Array<Proof>;
+};
+
+export class CashuWallet extends EventEmitter<WalletEvents> implements LNWallet {
+  #wallet: CashuWalletConfig;
+  #mint: CashuMint;
+
+  constructor(wallet: CashuWalletConfig) {
+    super();
+    this.#wallet = wallet;
+    this.#mint = new CashuMint(this.#wallet.url);
+  }
+
+  getConfig() {
+    return { ...this.#wallet };
+  }
+
+  canGetInvoices() {
+    return false;
+  }
+
+  canGetBalance() {
+    return true;
+  }
+
+  canAutoLogin() {
+    return true;
+  }
+
+  isReady() {
+    return true;
+  }
+
+  canCreateInvoice() {
+    return true;
+  }
+
+  canPayInvoice() {
+    return true;
+  }
+
+  async getInfo() {
+    return {
+      alias: "Cashu mint: " + this.#wallet.url,
+    } as WalletInfo;
+  }
+
+  async login(): Promise<boolean> {
+    if (this.#wallet.keysets.length === 0) {
+      const keys = await this.#mint.getKeys();
+      this.#wallet.keys = keys;
+      this.#wallet.keysets = [""];
+      this.onChange(this.#wallet);
+    }
+    await this.#checkProofs();
+    return true;
+  }
+
+  close(): Promise<boolean> {
+    return Promise.resolve(true);
+  }
+
+  async getBalance() {
+    return this.#wallet.proofs.reduce((acc, v) => (acc += v.amount), 0);
+  }
+
+  async createInvoice(req: InvoiceRequest) {
+    const rsp = await this.#mint.requestMint(req.amount);
+    return {
+      pr: rsp.pr,
+    } as WalletInvoice;
+  }
+
+  payInvoice(): Promise<WalletInvoice> {
+    throw new Error("Method not implemented.");
+  }
+
+  getInvoices(): Promise<WalletInvoice[]> {
+    return Promise.resolve([]);
+  }
+
+  async #checkProofs() {
+    if (this.#wallet.proofs.length == 0) return;
+
+    const checks = await this.#mint.check({
+      proofs: this.#wallet.proofs.map(a => ({ secret: a.secret })),
+    });
+
+    const filteredProofs = this.#wallet.proofs.filter((_, i) => checks.spendable[i]);
+    this.#wallet.proofs = filteredProofs;
+    if (filteredProofs.length !== checks.spendable.length) {
+      this.emit("change", JSON.stringify(this.#wallet));
+    }
+  }
+}