/**
 * Returns the number of handicap strokes a player receives on a given hole.
 * WHS allocation: distribute course_handicap strokes across holes by stroke index.
 */
export function strokesReceived(
  courseHandicap: number,
  strokeIndex: number,
  holesCount: number,
): number {
  if (courseHandicap <= 0) return 0
  const fullStrokes = Math.floor(courseHandicap / holesCount)
  const extraStrokes = courseHandicap % holesCount
  return fullStrokes + (strokeIndex <= extraStrokes ? 1 : 0)
}

/**
 * Net score on a hole (gross strokes minus strokes received).
 */
export function netStrokes(
  gross: number,
  courseHandicap: number,
  strokeIndex: number,
  holesCount: number,
): number {
  return gross - strokesReceived(courseHandicap, strokeIndex, holesCount)
}

/**
 * Score vs par as a display string: "−2", "E", "+1", "+3"
 */
export function formatVsPar(diff: number): string {
  if (diff === 0) return 'E'
  return diff > 0 ? `+${diff}` : `${diff}`
}

/**
 * CSS class for a gross score vs par (standard golf scorecard conventions).
 */
export function scoreColorClass(vsPar: number | null): string {
  if (vsPar === null) return ''
  if (vsPar <= -2) return 'bg-yellow-300 text-yellow-900 rounded-full'   // Eagle or better
  if (vsPar === -1) return 'bg-red-500 text-white rounded-full'           // Birdie
  if (vsPar === 0) return ''                                               // Par
  if (vsPar === 1) return 'border border-border rounded-sm'               // Bogey
  if (vsPar === 2) return 'border-2 border-border rounded-sm'             // Double
  return 'border-2 border-destructive rounded-sm text-destructive'        // Triple+
}