import {describe, it, expect} from 'vitest'
import {computeVisibleCount} from './tabFit'

const base = {gap: 60, chevronReserve: 110}
const widths = (n: number, w = 180) => Array.from({length: n}, () => w)

describe('computeVisibleCount', () => {
  it('sans layout : respecte maxVisibleTabs', () => {
    expect(computeVisibleCount({...base, count: 5, containerWidth: 0, tabWidths: [], maxVisibleTabs: 3})).toBe(3)
  })

  it('sans layout ni maxVisibleTabs : tous les onglets', () => {
    expect(computeVisibleCount({...base, count: 5, containerWidth: 0, tabWidths: []})).toBe(5)
  })

  it('tout tient : retourne le total (pas de chevrons)', () => {
    // 4×180 + 3×60 = 900 <= 1000
    expect(computeVisibleCount({...base, count: 4, containerWidth: 1000, tabWidths: widths(4)})).toBe(4)
  })

  it('trop large : additionne les vraies largeurs (pas la pire) — pas d\'effondrement à 1', () => {
    // total 7×180+6×60=1620 > 1400 ; avail=1400-110=1290 ; 180,420,660,900,1140,(1380>1290) → 5
    expect(computeVisibleCount({...base, count: 7, containerWidth: 1400, tabWidths: widths(7)})).toBe(5)
  })

  it('largeur étroite : montre ce qui tient (≥ 2 ici, pas 1)', () => {
    // avail=570-110=460 ; 180,(420),(660>460) → 2
    expect(computeVisibleCount({...base, count: 7, containerWidth: 570, tabWidths: widths(7)})).toBe(2)
  })

  it('maxVisibleTabs plafonne le résultat', () => {
    expect(computeVisibleCount({...base, count: 7, containerWidth: 1400, tabWidths: widths(7), maxVisibleTabs: 3})).toBe(3)
  })

  it('au moins 1 onglet si rien ne tient', () => {
    expect(computeVisibleCount({...base, count: 5, containerWidth: 150, tabWidths: widths(5, 300)})).toBe(1)
  })

  it('gère des largeurs hétérogènes', () => {
    // total 1080 > 1000 → fenêtré ; avail=1000-110=890 ; 300,560,820,(1080>890) → 3
    expect(computeVisibleCount({...base, count: 4, containerWidth: 1000, tabWidths: [300, 200, 200, 200]})).toBe(3)
  })
})