import { describe, expect, it } from 'vitest'
import {
  debtSeries,
  debtTotal,
  installmentLoad,
  monthEnd,
  monthIndex,
  monthName,
  remainingAfter,
} from './debt'

// Kaynak belgedeki 8 taksit (paidCount Kasım 2026 itibarıyla → ilk ay = Kasım − paid + 1)
const nov = monthIndex('2026-11')!
const plans = (
  [
    [271_761, 7, 5],
    [33_324, 9, 5],
    [11_945, 7, 5],
    [12_717, 7, 4],
    [17_067, 7, 3],
    [7_428, 7, 3],
    [18_202, 7, 2],
    [58_738, 3, 2],
  ] as const
).map(([monthly_amount, total_count, paid]) => ({
  monthly_amount,
  total_count,
  first_month: monthName(nov - paid + 1),
}))

describe('debt (backend ile aynı, kabul rakamları)', () => {
  it('totals', () => {
    expect(
      debtTotal({
        kmh: 0,
        positive_balance: 236_311,
        card_balance: 6_671_590,
        remaining_installments: 1_417_769,
      }),
    ).toBe(7_853_048)
    expect(
      debtTotal({
        kmh: 3_926_444,
        positive_balance: 0,
        card_balance: 2_994_854,
        remaining_installments: 986_587,
      }),
    ).toBe(7_907_885)
  })

  it('installment loads and remaining', () => {
    const loads = ['2026-11', '2026-12', '2027-01', '2027-02', '2027-03', '2027-04'].map((m) =>
      installmentLoad(plans, monthIndex(m)!),
    )
    expect(loads).toEqual([431_182, 431_182, 372_444, 88_738, 76_021, 18_202])
    expect(remainingAfter(plans, monthIndex('2026-10')!)).toBe(1_417_769)
    expect(remainingAfter(plans, nov)).toBe(986_587)
  })

  it('months', () => {
    expect(monthName(monthIndex('2026-12')! + 1)).toBe('2027-01')
    expect(monthIndex('2026-13')).toBeNull()
    expect(monthEnd('2026-11')).toBe('2026-11-30')
    expect(monthEnd('2028-02')).toBe('2028-02-29')
  })

  it('chart series: actual + target from the first snapshot', () => {
    const s = debtSeries(
      [
        { date: '2026-11-13', total: 7_907_885 },
        { date: '2026-10-31', total: 7_853_048 },
      ],
      [{ month: '2026-11', closing_target: 6_699_500 }],
    )
    expect(s.map((p) => [p.date, p.actual, p.target])).toEqual([
      ['2026-10-31', 7_853_048, 7_853_048],
      ['2026-11-13', 7_907_885, undefined],
      ['2026-11-30', undefined, 6_699_500],
    ])
  })
})

describe('plan integration', () => {
  it('finds the installments expense item by name', async () => {
    const { findInstallmentItem } = await import('./debt')
    const items = [
      { kind: 'income', name: 'Taksitler' },
      { kind: 'expense', name: 'Kira' },
      { kind: 'expense', name: ' TAKSİTLER ' },
    ]
    expect(findInstallmentItem(items)?.name).toBe(' TAKSİTLER ')
    expect(findInstallmentItem([{ kind: 'expense', name: 'Taksit' }])).toBeTruthy()
    expect(findInstallmentItem([{ kind: 'expense', name: 'Taksitli alışveriş' }])).toBeUndefined()
  })
})