import {z} from 'zod'

export type GetApiV01DiscoveryResourcesAggregationsArgs = {q: string, search_scope?: ('all' | 'title' | 'journal_title' | 'contributor' | 'subject' | 'series' | 'callnumber') | undefined, 'filters[*]'?: string | undefined};

export type GetApiV01DiscoveryResourcesAggregationsOptions = {baseUrl?: string | undefined, fetch?: typeof fetch | undefined};

export const aggregationValue = z.object({value: z.string().optional(), count: z.number().int().optional()});

export const aggregation = z.object({"@type": z.literal("nypl:Aggregation").optional(), "@id": z.string().optional(), field: z.string().optional(), values: z.array(aggregationValue).optional()});

export const resourceAggregationsResponse = z.object({"@context": z.string().optional(), "@type": z.literal("itemListElement").optional(), "@id": z.string().optional(), itemListElement: z.array(aggregation).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
};

/**
 * Resource Search Aggregations
 * 
 * GET /v0.1/discovery/resources/aggregations
 */
export const getApiV01DiscoveryResourcesAggregations = async (args: GetApiV01DiscoveryResourcesAggregationsArgs, options?: GetApiV01DiscoveryResourcesAggregationsOptions) => {
const {baseUrl = "https://platform.nypl.org/api", fetch: fetchFn = fetch} = options ?? {}

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

if (args.q != null) query.append("q", String(args.q))
if (args.search_scope != null) query.append("search_scope", String(args.search_scope))
if (args['filters[*]'] != null) query.append("filters[*]", String(args['filters[*]']))

const url = `${baseUrl.replace(/\/+$/, '')}/v0.1/discovery/resources/aggregations${query.size > 0 ? `?${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(resourceAggregationsResponse, await res.json())
};