const CUSTOM_PAGE_SIZE_STORAGE_KEY = "cowa:custom-records-per-page-options:v1"

function normalizePageSizeOptions(values: number[]) {
  return Array.from(
    new Set(values.filter((value) => Number.isInteger(value) && value > 0))
  ).sort((a, b) => a - b)
}

function normalizeCustomPageSizeCache(value: unknown) {
  if (!Array.isArray(value)) return []

  return normalizePageSizeOptions(value.map((item) => Number(item)))
}

export function resolvePageSizeWithinOptions(
  pageSize: number | undefined,
  availableOptions: number[],
  fallbackPageSize: number
) {
  const normalizedOptions = normalizePageSizeOptions(availableOptions)

  if (
    typeof pageSize === "number" &&
    Number.isInteger(pageSize) &&
    pageSize > 0 &&
    normalizedOptions.includes(pageSize)
  ) {
    return pageSize
  }

  if (
    Number.isInteger(fallbackPageSize) &&
    fallbackPageSize > 0 &&
    normalizedOptions.includes(fallbackPageSize)
  ) {
    return fallbackPageSize
  }

  return normalizedOptions[0] ?? fallbackPageSize
}

export function getPersistedPageSizeOptions(defaultOptions: number[]) {
  const normalizedDefaultOptions = normalizePageSizeOptions(defaultOptions)

  if (typeof window === "undefined") {
    return normalizedDefaultOptions
  }

  try {
    const rawValue = window.localStorage.getItem(CUSTOM_PAGE_SIZE_STORAGE_KEY)
    if (!rawValue) {
      return normalizedDefaultOptions
    }

    const parsedValue = JSON.parse(rawValue) as
      | { state?: { customPageSizeCache?: unknown } }
      | number[]
      | null

    const customPageSizeCache = Array.isArray(parsedValue)
      ? normalizeCustomPageSizeCache(parsedValue)
      : normalizeCustomPageSizeCache(parsedValue?.state?.customPageSizeCache)

    return normalizePageSizeOptions([
      ...normalizedDefaultOptions,
      ...customPageSizeCache,
    ])
  } catch {
    return normalizedDefaultOptions
  }
}