import { ItemListItem } from "@/types/master-data"

/** Rounds a sales unit price to 2dp, half away from zero (matches the server's SalesPricingService).
 * Shifts via the exponent string rather than `* 100` so binary-float cases like 1.005 round up. */
export function roundPrice(value: number): number {
  const shifted = Number(`${Math.round(Number(`${Math.abs(value)}e2`))}e-2`)
  // Values JS prints in exponent form (e.g. 1e-7) can't take the string shift — those are ~0 anyway.
  const rounded = Number.isFinite(shifted) ? shifted : Math.round(Math.abs(value) * 100) / 100
  return value < 0 ? -rounded : rounded
}

/** A unit price input's value as a 2dp price, or null when cleared. */
export function parsePriceInput(value: string): number | null {
  if (value === "") return null
  const n = Number(value)
  return Number.isFinite(n) ? roundPrice(n) : null
}

export function getSuggestedUnitPrice(items: ItemListItem[], itemId: number | null | undefined): number | null {
  if (!itemId) return null
  const price = items.find((item) => item.itemId === itemId)?.sellingFlatPrice
  return price === null || price === undefined ? null : roundPrice(price)
}