import { describe, it, expect, beforeAll } from 'vitest'
import * as db from '../src/database.js'

const pubkey = 'dup-test-' + Date.now()
const email = 'dup-test-' + Date.now() + '@example.com'
let token: string

describe('Duplicate subscription prevention — idempotent re-register after confirm', () => {
  beforeAll(async () => {
    await db.migrate()
  })

  it('registers a subscription (fresh)', async () => {
    const sub = await db.insertSubscription(pubkey, email, 'daily')
    expect(sub).toBeTruthy()
    expect(sub!.confirmed_at).toBeFalsy()
    expect(sub!.unsubscribed_at).toBeFalsy()
    token = sub!.key
  })

  it('confirms the subscription', async () => {
    const result = await db.confirmSubscription(token)
    expect(result).toBeTruthy()
    expect(result!.alreadyConfirmed).toBe(false)
    expect(result!.sub.confirmed_at).toBeTruthy()
  })

  it('re-registers with the same email and frequency (idempotent PUT)', async () => {
    // This simulates a second PUT from the client with identical params.
    // The bug would create a second active row + send a new confirmation email.
    const sub = await db.insertSubscription(pubkey, email, 'daily')
    expect(sub).toBeTruthy()
    // Must return the existing confirmed row, NOT a fresh unconfirmed row
    expect(sub!.confirmed_at).toBeTruthy()
    expect(sub!.unsubscribed_at).toBeFalsy()

    // The key must remain unchanged — a new row would have a different key
    expect(sub!.key).toBe(token)
  })

  it('has exactly one active row for this pubkey', async () => {
    // getSubscriptionByPubkey filters by unsubscribed_at IS NULL and
    // returns at most one row (enforced by the partial unique index).
    // If a second active row exists, the index is absent or bypassed.
    const active = await db.getSubscriptionByPubkey(pubkey)
    expect(active).toBeTruthy()
    expect(active!.confirmed_at).toBeTruthy()
    expect(active!.key).toBe(token)
  })
})