import {z} from 'zod'

export type GetApiV01DiscoverySubjectsBrowseArgs = {q?: string | undefined, page?: number | undefined, per_page?: number | undefined, sort?: ('relevance' | 'preferredTerm' | 'count') | undefined, sort_direction?: ('asc' | 'desc') | undefined, search_scope?: ('has' | 'starts_with') | undefined};

export type GetApiV01DiscoverySubjectsBrowseOptions = {baseUrl?: string | undefined, fetch?: typeof fetch | undefined};

export const subject = z.object({preferredTerm: z.string().optional(), count: z.number().int().optional(), uri: z.string().optional(), variants: z.array(z.string()).optional(), narrowerTerms: z.array(z.string()).optional(), broaderTerms: z.array(z.string()).optional()});

export const subjectsResponse = z.object({"@type": z.literal("subjectList").optional(), page: z.number().int().optional(), perPage: z.number().int().optional(), subjects: z.array(subject).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
};

/**
 * List subjects and counts.
 * 
 * GET /v0.1/discovery/subjects/browse
 */
export const getApiV01DiscoverySubjectsBrowse = async (args: GetApiV01DiscoverySubjectsBrowseArgs, options?: GetApiV01DiscoverySubjectsBrowseOptions) => {
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.page != null) query.append("page", String(args.page))
if (args.per_page != null) query.append("per_page", String(args.per_page))
if (args.sort != null) query.append("sort", String(args.sort))
if (args.sort_direction != null) query.append("sort_direction", String(args.sort_direction))
if (args.search_scope != null) query.append("search_scope", String(args.search_scope))

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