import { ValidationError } from './validationError'

const DEFAULT_FETCH_OPTIONS = {
  method: 'GET',
  mode: 'cors' as RequestMode,
  cache: 'no-cache' as RequestCache,
  credentials: 'same-origin' as RequestCredentials,
  headers: {
    'Content-Type': 'application/json',
  },
  referrerPolicy: 'no-referrer' as ReferrerPolicy,
}

export type FetchOptions = Omit<RequestInit, 'body'> & {
  body?: object
}

export default async function fetchJSON(
  url: string,
  options: FetchOptions = {}
) {
  const response = await fetch(url, {
    ...DEFAULT_FETCH_OPTIONS,
    ...options,
    body: !!options.body ? JSON.stringify(options.body) : undefined,
  })

  if (response.status === 400) {
    const error = await response.json()
    throw new ValidationError(error.errors)
  }

  if (!response.ok) {
    throw Error(
      'Sorry, konnte nicht gespeichert werden. Bitte versuch es später nochmal!'
    )
  }

  return response.json()
}