const decrementPriceEventDays = (
  priceEvents: Partial<Record<string, farmhand.priceEvent>>
): Partial<Record<string, farmhand.priceEvent>> =>
  Object.keys(priceEvents).reduce(
    (acc: Record<string, farmhand.priceEvent>, key) => {
      const priceEvent = priceEvents[key]

      if (!priceEvent) return acc

      const { itemId, daysRemaining } = priceEvent

      if (daysRemaining > 1) {
        acc[key] = { itemId, daysRemaining: daysRemaining - 1 }
      }

      return acc
    },
    {}
  )

export const updatePriceEvents = (state: farmhand.state): farmhand.state => {
  const { priceCrashes, priceSurges } = state

  return {
    ...state,
    priceCrashes: decrementPriceEventDays(priceCrashes),
    priceSurges: decrementPriceEventDays(priceSurges),
  }
}