import { ApolloClient, ApolloClientOptions } from 'apollo-client'
import { ApolloLink } from 'apollo-link'
import cache from './cache/apolloCache'

const IS_BROWSER = typeof window === 'object'

export interface CreateApolloClientOptions {
  link: ApolloLink
}

/**
 * @example
 * import { createApolloClient, consoleLink, errorLink, httpLink, persistCache } from 'create-apollo-client'
 * // create your own stateLink if you want, put it before httpLink
 * const link = ApolloLink.from([consoleLink, errorLink, stateLink, httpLink])
 * export const { client, cache } = createApolloClient({ link })
 * // use client side query persistance, note, this is slow
 * persistCache()
 */
function createApolloClient(options: CreateApolloClientOptions) {
  /**
   * @note can also export this top level to be mutated...
   */
  const clientConfig: ApolloClientOptions<any> = {
    link: options.link,
    cache,
    ssrMode: IS_BROWSER === false,
    connectToDevTools: IS_BROWSER === true,
    ssrForceFetchDelay: IS_BROWSER ? 100 : undefined,
  }

  const client = new ApolloClient(clientConfig)
  return client
}

export { createApolloClient }