import { describe, expect, it } from 'vitest'
import { computeStageRowHeight } from '@/lib/timetable/row-height'

/**
 * One-line helper, four assertion cases — keep this surface tight; this
 * is the canonical row-height math for both StageRow content and the
 * sticky-left StageHeaderCell. If either side drifts, the freeze panes
 * misalign in the browser. The math:
 *
 *   max(1, laneCount) × (laneHeight + lanePad) + lanePad
 *
 * with the canonical constants laneHeight=44, lanePad=4 → 48 per lane + 4.
 */
const LANE_HEIGHT = 44
const LANE_PAD = 4

describe('computeStageRowHeight', () => {
  it('falls back to single-lane height when laneCount is 0', () => {
    expect(computeStageRowHeight(0, LANE_HEIGHT, LANE_PAD)).toBe(52)
  })

  it('returns 52px for laneCount=1', () => {
    expect(computeStageRowHeight(1, LANE_HEIGHT, LANE_PAD)).toBe(52)
  })

  it('returns 148px for laneCount=3', () => {
    expect(computeStageRowHeight(3, LANE_HEIGHT, LANE_PAD)).toBe(148)
  })

  it('returns 484px for laneCount=10 (10 × 48 + 4)', () => {
    expect(computeStageRowHeight(10, LANE_HEIGHT, LANE_PAD)).toBe(484)
  })
})