import { describe, expect, it } from 'vitest'
import type { BillTotals } from '@sims/domain'
import type { LineInput } from '@sims/billing-engine'
import { buildQueuedBill, nextProvisionalToken, toOfflineBillBody, type QueuedBill } from '../src/offline'

const TOTALS: BillTotals = {
  grossPaise: 14_500, discountPaise: 0, taxablePaise: 12_288,
  cgstPaise: 1_106, sgstPaise: 1_106, igstPaise: 0, cessPaise: 0,
  roundOffPaise: 0, payablePaise: 14_500, savingsVsMrpPaise: 500,
}
const LINES: LineInput[] = [{
  itemId: 'i-103', name: 'Surf Excel 1kg', hsn: '3402', qty: 1,
  unitCode: 'PCS', unitPricePaise: 14_500, priceIncludesTax: true, taxClassCode: 'GST18',
}]

describe('S4 offline queue — provisional tokens', () => {
  it('formats OFF-n from the sequence', () => {
    expect(nextProvisionalToken(1)).toBe('OFF-1')
    expect(nextProvisionalToken(42)).toBe('OFF-42')
  })
})

describe('S4 offline queue — buildQueuedBill', () => {
  const base = {
    seq: 2, storeId: 's1', counterId: 'c2', cashierId: 'u1', shiftId: 'sh1',
    businessDate: '2026-07-10', lines: LINES,
    payments: [{ mode: 'CASH', amountPaise: 14_500 }],
    totals: TOTALS, now: 1_700_000_000_000,
  }

  it('assigns a client uuidv7 id, a matching provisional token, and an ISO createdAt', () => {
    const q = buildQueuedBill(base)
    expect(q.id).toMatch(/^[0-9a-f]{8}-[0-9a-f]{4}-7[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/)
    expect(q.provisionalToken).toBe('OFF-2')
    expect(q.seq).toBe(2)
    expect(q.createdAt).toBe(new Date(1_700_000_000_000).toISOString())
    expect(q.totals.payablePaise).toBe(14_500)
  })

  it('omits optional customer / override fields when absent', () => {
    const q = buildQueuedBill(base)
    expect('customerId' in q).toBe(false)
    expect('customerName' in q).toBe(false)
    expect('buyerGstin' in q).toBe(false)
    expect('overrides' in q).toBe(false)
  })

  it('keeps only the customer id and non-empty overrides — never customer PII (M11)', () => {
    const q = buildQueuedBill({
      ...base,
      customerId: 'p1',
      overrides: [{ itemId: 'i-103', kind: 'price', before: 15_000, after: 14_500, approvalId: 'a1' }],
    })
    expect(q.customerId).toBe('p1')
    // M11: the queued record must NOT carry the buyer's name or GSTIN — the server
    // re-resolves both from customerId at drain, so no PII lands on the shared counter PC.
    expect('customerName' in q).toBe(false)
    expect('buyerGstin' in q).toBe(false)
    expect(q.overrides).toHaveLength(1)
  })

  it('drops an empty overrides array rather than persisting it', () => {
    const q = buildQueuedBill({ ...base, overrides: [] })
    expect('overrides' in q).toBe(false)
  })
})

describe('S4 offline queue — toOfflineBillBody', () => {
  it('maps to the drain payload: keeps the client id, sets clientPayablePaise, drops display-only fields', () => {
    const q: QueuedBill = buildQueuedBill({
      seq: 1, storeId: 's1', counterId: 'c2', cashierId: 'u1', shiftId: 'sh1',
      customerId: 'p1',
      businessDate: '2026-07-10', lines: LINES,
      payments: [{ mode: 'CASH', amountPaise: 14_500 }], totals: TOTALS,
    })
    const body = toOfflineBillBody(q)
    expect(body.id).toBe(q.id)
    expect(body.clientPayablePaise).toBe(14_500)
    expect(body.customerId).toBe('p1')
    // SEC fix: cashier/tenant come from the server session, never the body
    expect('cashierId' in body).toBe(false)
    // M11: no customer PII is stored offline, so none can travel in the drain body
    expect('customerName' in body).toBe(false)
    expect('buyerGstin' in body).toBe(false)
    expect('totals' in body).toBe(false)
    expect('provisionalToken' in body).toBe(false)
  })
})