import {globalFormError} from './formErrors'

export const emptyToNull = (
  value: string | null | undefined,
): string | null => {
  if (typeof value !== 'string') {
    return null
  }
  const result = value.trim()
  if (!result) {
    return null
  }
  return result
}

export const requiredString = (value: string | null | undefined): string => {
  const result = emptyToNull(value)
  if (!result) {
    // Should not happen, validators should have caught already
    throw globalFormError('Required field missing')
  }
  return result
}

export const toNumberOrNull = (
  value: number | string | null | undefined,
): number | null => {
  if (value == null) {
    return null
  }
  const parsed = typeof value === 'number' ? value : Number.parseFloat(value)
  if (Number.isNaN(parsed)) {
    return null
  }
  return parsed
}

export const requiredNumber = (
  value: number | string | null | undefined,
): number => {
  const result = toNumberOrNull(value)
  if (result == null) {
    // Should not happen, validators should have caught already
    throw globalFormError('Required number missing')
  }
  return result
}