import express from 'express';
import request from 'supertest';
import { apiKeyAuth, Customer, InMemoryCustomerRepo } from '../src/auth';
import { meter } from '../src/meter';
import { DEFAULT_PRICING } from '../src/pricing';
import { InMemoryUsageRepo } from '../src/usage';

const FREE_ADA: Customer = { id: 'cust_1', name: 'Ada', tierId: 'free', apiKey: 'key-ada' };

function buildApp(seed: Customer[] = [FREE_ADA]) {
  const customers = new InMemoryCustomerRepo(seed);
  const usage = new InMemoryUsageRepo();
  const app = express();
  app.use(express.json());
  app.use(apiKeyAuth(customers));
  app.post('/transform', meter('transform', usage, DEFAULT_PRICING), (req, res) =>
    res.json({ quote: res.locals.quote }),
  );
  app.post('/storage', meter('storage', usage, DEFAULT_PRICING), (req, res) =>
    res.json({ quote: res.locals.quote }),
  );
  app.post('/experimental', meter('experimental', usage, DEFAULT_PRICING), (req, res) =>
    res.json({ quote: res.locals.quote }),
  );
  return { app, usage };
}

describe('meter middleware', () => {
  it('quotes a fixed endpoint at the multiplied tier price and records usage', async () => {
    const { app, usage } = buildApp();
    const res = await request(app)
      .post('/transform')
      .set('x-api-key', 'key-ada')
      .send({ text: 'hi' });
    expect(res.status).toBe(200);
    expect(res.body.quote.totalCents).toBe(4); // free tier, multiplier 1
    const entries = usage.listFor('cust_1');
    expect(entries).toHaveLength(1);
    expect(entries[0].endpointId).toBe('transform');
    expect(entries[0].cents).toBe(4);
  });

  it('charges per KB of metadata on variable endpoints', async () => {
    const { app } = buildApp();
    const res = await request(app)
      .post('/storage')
      .set('x-api-key', 'key-ada')
      .send({ metadata: { note: 'x'.repeat(2048) } });
    // JSON of metadata is 2059 bytes -> 3 KB -> list 10 + 3 * 1 = 13
    expect(res.body.quote.totalCents).toBe(13);
  });

  it('applies a per-customer multiplier override', async () => {
    const { app } = buildApp([
      { id: 'cust_vip', name: 'Vip', tierId: 'free', apiKey: 'key-vip', multiplierOverride: 0.5 },
    ]);
    const res = await request(app)
      .post('/transform')
      .set('x-api-key', 'key-vip')
      .send({ text: 'hi' });
    expect(res.body.quote.totalCents).toBe(2); // list 4 x override 0.5
  });

  it('returns 401 when no customer is attached', async () => {
    const usage = new InMemoryUsageRepo();
    const app = express();
    app.use(express.json());
    app.post('/transform', meter('transform', usage, DEFAULT_PRICING), (req, res) =>
      res.json({}),
    );
    const res = await request(app).post('/transform').send({ text: 'hi' });
    expect(res.status).toBe(401);
    expect(usage.listFor('cust_1')).toHaveLength(0);
  });

  it('returns 403 for an endpoint with no price rule on the caller tier', async () => {
    const { app, usage } = buildApp();
    const res = await request(app)
      .post('/experimental')
      .set('x-api-key', 'key-ada')
      .send({});
    expect(res.status).toBe(403);
    expect(res.body.error).toMatch(/No price rule/);
    expect(usage.listFor('cust_1')).toHaveLength(0);
  });
});