import {z} from 'zod'

export type GetApiUsersSubscribersArgs = {ids: Array<string>};

export type GetApiUsersSubscribersOptions = {baseUrl: string, fetch?: typeof fetch | undefined};

export const versionMetadata = z.object({service: z.string(), version: z.string()});

export const userSubscribers = z.object({user_id: z.string(), subscriber_ids: z.array(z.string()).optional()});

export const bulkSubscribersResponse = z.object({latest_chain_block: z.number().int(), latest_indexed_block: z.number().int(), latest_chain_slot_plays: z.number().int(), latest_indexed_slot_plays: z.number().int(), signature: z.string(), timestamp: z.string(), version: versionMetadata, data: z.array(userSubscribers).optional()});

export const validateResponse = async <Output>(
  schema: {
    readonly '~standard': {
      readonly validate: (value: unknown) => ({ readonly value: Output; readonly issues?: undefined } | { readonly issues: ReadonlyArray<{ readonly message: string; readonly path?: ReadonlyArray<PropertyKey | { readonly key: PropertyKey }> | undefined }> }) | Promise<{ readonly value: Output; readonly issues?: undefined } | { readonly issues: ReadonlyArray<{ readonly message: string; readonly path?: ReadonlyArray<PropertyKey | { readonly key: PropertyKey }> | undefined }> }>
    }
  },
  value: unknown
): Promise<Output> => {
  const result = await schema['~standard'].validate(value)

  if (result.issues !== undefined) {
    const detail = result.issues
      .map(({ message, path }) =>
        path?.length
          ? `${path.map((segment) => String(typeof segment === 'object' ? segment.key : segment)).join('.')}: ${message}`
          : message
      )
      .join('; ')

    throw new Error(`Response does not match the schema: ${detail}`, { cause: { issues: result.issues } })
  }

  return result.value
};

/**
 * All users that subscribe to the provided users
 * 
 * GET /users/subscribers
 */
export const getApiUsersSubscribers = async (args: GetApiUsersSubscribersArgs, options: GetApiUsersSubscribersOptions) => {
const {baseUrl, fetch: fetchFn = fetch} = options ?? {}

const query = new URLSearchParams()
const headers = new Headers()
headers.set('accept', "application/json")

if (args.ids != null) query.append("ids", args.ids.join(','))

const url = `${baseUrl.replace(/\/+$/, '')}/users/subscribers${query.size > 0 ? `?${query}` : ''}`

const res = await fetchFn(url, {method: "GET", headers})

if (!res.ok) throw new Error(`Request failed with status ${res.status}`, {cause: {status: res.status, body: await res.text()}})

return validateResponse(bulkSubscribersResponse, await res.json())
};