import {z} from 'zod'

export type GetApiV1GoogleScholarSearchArgs = {q: string, hl?: string | undefined, as_ylo?: (number | null) | undefined, as_yhi?: (number | null) | undefined, as_sdt?: string | undefined, page?: number | undefined, num?: number | undefined};

export type GetApiV1GoogleScholarSearchOptions = {baseUrl?: string | undefined, apiKey?: string | undefined, fetch?: typeof fetch | undefined};

export const scholarResult = z.object({position: z.number().int().nullable().optional(), title: z.string(), link: z.string().nullable().optional(), snippet: z.string().nullable().optional(), authors: z.array(z.string()).optional(), publication_info: z.string().nullable().optional(), cited_by_count: z.number().int().nullable().optional(), cited_by_link: z.string().nullable().optional(), related_link: z.string().nullable().optional(), versions_count: z.number().int().nullable().optional(), pdf_link: z.string().nullable().optional()});

export const scholarSearchResponse = z.object({results: z.array(scholarResult).optional(), query: z.string(), language: z.string().optional(), total_results: z.number().int().nullable().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
};

/**
 * Search Google Scholar
 * 
 * GET /v1/google/scholar/search
 */
export const getApiV1GoogleScholarSearch = async (args: GetApiV1GoogleScholarSearchArgs, options?: GetApiV1GoogleScholarSearchOptions) => {
const {baseUrl = "https://scrapebadger.com", fetch: fetchFn = fetch, apiKey} = 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.hl != null) query.append("hl", String(args.hl))
if (args.as_ylo != null) query.append("as_ylo", String(args.as_ylo))
if (args.as_yhi != null) query.append("as_yhi", String(args.as_yhi))
if (args.as_sdt != null) query.append("as_sdt", String(args.as_sdt))
if (args.page != null) query.append("page", String(args.page))
if (args.num != null) query.append("num", String(args.num))
if (apiKey !== undefined) headers.set("x-api-key", apiKey)

const url = `${baseUrl.replace(/\/+$/, '')}/v1/google/scholar/search${query.size > 0 ? `?${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(scholarSearchResponse, await res.json())
};