rudder-js-sdk/test/e2e-prod/purchase.e2e.test.ts

import { describe, it, expect, beforeAll } from 'vitest';
import { adminApi, freshPlayer, grantCurrency, loadArtifact, withReadRetry } from './_setup/harness.js';
import type { SeedArtifact } from './_setup/types.js';
import type { RudderClient } from '../../src/client/RudderClient.js';
import type { OfferHandle } from '../../src/state/shops.js';

// Exercises the (newly implemented) wallet + inventory + purchase backend end-to-end:
// admin grant -> debit on buy -> inventory credit -> idempotency -> max_purchases -> insufficient funds.
interface AdminWalletDetails {
  currencyCode: string;
  balance: number;
}
interface AdminInventoryItem {
  slug: string;
  amount: number;
}
interface AdminPlayerDetails {
  wallets?: AdminWalletDetails[];
  inventory?: AdminInventoryItem[];
}

describe('e2e-prod: purchase (wallet/inventory/limits)', () => {
  let artifact: SeedArtifact;
  beforeAll(() => {
    artifact = loadArtifact();
  });

  async function resolvePaidOffer(client: RudderClient): Promise<OfferHandle> {
    const stores = await withReadRetry(
      () => client.stores.reload(),
      (s) => s.some((store) => store.name === artifact.store.name && store.offers.length > 0),
    );
    const store = stores.find((s) => s.name === artifact.store.name)!;
    return store.offers.find((o) => o.name === artifact.store.paidOfferName)!;
  }

  async function balance(client: RudderClient, currency: string): Promise<number> {
    const profile = await client.player.reload();
    // int64 fields serialize as JSON strings via protojson — coerce to number.
    return Number(profile.wallets?.find((w) => w.currency === currency)?.balance ?? 0);
  }

  it('grants currency, debits on buy, credits inventory, is idempotent, and enforces the purchase limit', async () => {
    const client = await freshPlayer(artifact);
    const playerId = (await client.player.reload()).player!.id!;
    const api = adminApi(artifact);
    const currency = artifact.store.paidPrice.currency;
    const price = artifact.store.paidPrice.amount;
    const offer = await resolvePaidOffer(client);

    // 1. Grant currency via the admin endpoint.
    await grantCurrency(artifact, playerId, currency, 1000);
    const granted = await withReadRetry(
      () => balance(client, currency),
      (b) => b === 1000,
    );
    expect(granted).toBe(1000);

    // 2. First paid buy: success + wallet debited.
    const buy1 = await offer.buy();
    expect(buy1.success).toBe(true);
    expect(buy1.purchaseId).toBeTruthy();
    expect(await balance(client, currency)).toBe(1000 - price);

    // 3. Inventory credited (verified via admin player details).
    const details = await api.get<AdminPlayerDetails>(
      `/platform/v1/projects/${artifact.projectId}/players/${playerId}?environment=${artifact.environment}`,
    );
    const inv = details.inventory?.find((i) => i.slug === artifact.item.id);
    expect(Number(inv?.amount)).toBe(artifact.store.paidGrantAmount);

    // 4. Idempotency: the same key twice charges once.
    const key = crypto.randomUUID();
    const a = await offer.buy({ idempotencyKey: key });
    const b = await offer.buy({ idempotencyKey: key });
    expect(a.success).toBe(true);
    expect(b.success).toBe(true);
    expect(await balance(client, currency)).toBe(1000 - price * 2);

    // 5. max_purchases (2) reached -> a new distinct buy fails (no charge).
    const overLimit = await offer.buy();
    expect(overLimit.success).toBe(false);
    expect(overLimit.error ?? '').toContain('limit');
    expect(await balance(client, currency)).toBe(1000 - price * 2);
  });

  it('rejects a paid purchase with insufficient funds', async () => {
    const poor = await freshPlayer(artifact);
    const offer = await resolvePaidOffer(poor);
    const res = await offer.buy();
    expect(res.success).toBe(false);
    expect(res.error ?? '').toContain('insufficient');
  });
});