import {z} from 'zod'

export type GetApiTransactionPoolArgs = {fields?: string | undefined, 'shard-id'?: string | undefined, 'by-sender'?: string | undefined, 'last-nonce'?: boolean | undefined, 'nonce-gaps'?: boolean | undefined};

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

export const wrappedTransaction = z.object({txFields: z.object({}).optional()});

export const transactionsPool = z.object({regularTransactions: z.array(wrappedTransaction).optional(), rewards: z.array(wrappedTransaction).optional(), smartContractResults: z.array(wrappedTransaction).optional()});

export const transactionsPoolResponse = z.object({data: transactionsPool.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
};

/**
 * returns the transactions pool for all shards.
 * 
 * GET /transaction/pool
 */
export const getApiTransactionPool = async (args: GetApiTransactionPoolArgs, options: GetApiTransactionPoolOptions) => {
const {baseUrl, fetch: fetchFn = fetch} = options ?? {}

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

if (args.fields != null) query.append("fields", String(args.fields))
if (args['shard-id'] != null) query.append("shard-id", String(args['shard-id']))
if (args['by-sender'] != null) query.append("by-sender", String(args['by-sender']))
if (args['last-nonce'] != null) query.append("last-nonce", String(args['last-nonce']))
if (args['nonce-gaps'] != null) query.append("nonce-gaps", String(args['nonce-gaps']))

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