"use strict";

const test = require("node:test");
const assert = require("node:assert/strict");
const { WalletStore } = require("../src/lib/wallet");

test("applies credit and debit transactions", () => {
  const wallet = new WalletStore();

  wallet.applyTransaction({
    userId: "u1",
    type: "credit",
    amount: 5,
    reason: "topup",
    idempotencyKey: "evt-1",
  });

  wallet.applyTransaction({
    userId: "u1",
    type: "debit",
    amount: 2,
    reason: "article_generation",
    idempotencyKey: "evt-2",
  });

  assert.equal(wallet.getBalance("u1"), 3);
});

test("prevents overdraft debits", () => {
  const wallet = new WalletStore();
  assert.throws(() => {
    wallet.applyTransaction({
      userId: "u1",
      type: "debit",
      amount: 1,
      reason: "article_generation",
      idempotencyKey: "evt-3",
    });
  }, /insufficient_credits/);
});

test("is idempotent by idempotency key", () => {
  const wallet = new WalletStore();

  const first = wallet.applyTransaction({
    userId: "u1",
    type: "credit",
    amount: 4,
    reason: "topup",
    idempotencyKey: "evt-4",
  });

  const second = wallet.applyTransaction({
    userId: "u1",
    type: "credit",
    amount: 999,
    reason: "topup",
    idempotencyKey: "evt-4",
  });

  assert.equal(first.id, second.id);
  assert.equal(wallet.getBalance("u1"), 4);
});