export type InputRecord = Record<string, unknown>

export function inputRecord(value: unknown): InputRecord {
  if (value === null || typeof value !== 'object' || Array.isArray(value)) {
    throw new Error('Input must be an object.')
  }
  return value as InputRecord
}

export function requiredString(input: InputRecord, key: string): string {
  const value = input[key]
  if (typeof value !== 'string' || value.trim().length === 0) {
    throw new Error(key + ' is required.')
  }
  return value
}

export function optionalString(input: InputRecord, key: string): string | undefined {
  const value = input[key]
  if (value === undefined || value === null || value === '') return undefined
  if (typeof value !== 'string') throw new Error(key + ' must be a string.')
  return value
}

export function boundedPageSize(value: unknown, fallback = 100): number {
  if (value === undefined || value === null) return fallback
  if (!Number.isInteger(value) || Number(value) < 1 || Number(value) > 100) {
    throw new Error('pageSize must be an integer from 1 through 100.')
  }
  return Number(value)
}

export function optionalRecord(input: InputRecord, key: string): InputRecord | undefined {
  const value = input[key]
  if (value === undefined || value === null) return undefined
  if (typeof value !== 'object' || Array.isArray(value)) {
    throw new Error(key + ' must be an object.')
  }
  return value as InputRecord
}

export function requiredRecord(input: InputRecord, key: string): InputRecord {
  const value = optionalRecord(input, key)
  if (value === undefined) throw new Error(key + ' is required.')
  return value
}

export function optionalArray(input: InputRecord, key: string): unknown[] | undefined {
  const value = input[key]
  if (value === undefined || value === null) return undefined
  if (!Array.isArray(value)) throw new Error(key + ' must be an array.')
  return value
}