import {z} from 'zod'

export type GetApiBuyBatchArgs = {urls: string, format?: ('text' | 'markdown') | undefined};

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

export const getApiBuyBatchResponse = z.object({ok: z.boolean(), url: z.string(), status: z.number().int().optional(), text: z.string().optional(), fetchedAt: z.string().optional(), data: z.object({merkleRoot: z.string().optional(), leafCount: z.number().int().optional(), requested: z.number().int().optional(), okCount: z.number().int().optional(), failCount: z.number().int().optional(), leafTag: z.string().optional(), nodeTag: z.string().optional(), pages: z.array(z.object({index: z.number().int().optional(), url: z.string().optional(), ok: z.boolean().optional(), status: z.number().int().optional(), title: z.string().optional(), text: z.string().optional(), contentHash: z.string().optional(), leafHash: z.string().optional(), proof: z.array(z.object({side: z.enum(["left", "right"]).optional(), hash: z.string().optional()})).optional(), bytes: z.number().int().optional(), contentType: z.string().optional(), redirects: z.array(z.string()).optional(), error: z.string().optional()})).optional(), dropped: z.array(z.string()).optional()}).optional(), error: z.string().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
};

/**
 * MERCURY Cited Batch — signed multi-page snapshot (Merkle root over every page's contentHash + per-page proofs)
 * 
 * GET /buy/batch
 */
export const getApiBuyBatch = async (args: GetApiBuyBatchArgs, options?: GetApiBuyBatchOptions) => {
const {baseUrl = "https://network.mercury-hq.com", fetch: fetchFn = fetch} = options ?? {}

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

if (args.urls != null) query.append("urls", String(args.urls))
if (args.format != null) query.append("format", String(args.format))

const url = `${baseUrl.replace(/\/+$/, '')}/buy/batch${query.size > 0 ? `?${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(getApiBuyBatchResponse, await res.json())
};