import {z} from 'zod'

export type MerchantPaymentStatus = 'PENDING' | 'IDENTIFIED' | 'AUTHORIZED' | 'AUTHORIZATION_FAILED' | 'SUCCEEDED' | 'FAILED' | 'CANCELLED' | 'EXPIRED' | 'PENDING_MERCHANT_ACKNOWLEDGEMENT' | 'VOIDED';

export type MerchantCallback = {paymentId: string, currency: string, amount: number, description?: string | undefined, reference?: string | undefined, createdAt: string, expireAt?: string | undefined, succeededAt?: string | undefined, status: MerchantPaymentStatus, debtor: {iban: string, name?: string | undefined}};

export type CreateApiCallbackArgs = {Signature: string, 'User-Agent': string, 'Content-Type': string, body: MerchantCallback};

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

export const createApiCallbackResponse = z.object({});

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
};

/**
 * notify merchants about statuses changes
 * 
 * POST /callback
 */
export const createApiCallback = async (args: CreateApiCallbackArgs, options?: CreateApiCallbackOptions) => {
const {baseUrl = "https://merchant.api.preprod.bancontact.net", fetch: fetchFn = fetch, JWSRequestSignaturePayment} = options ?? {}

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

if (args.Signature != null) headers.set("Signature", String(args.Signature))
if (args['User-Agent'] != null) headers.set("User-Agent", String(args['User-Agent']))
if (args['Content-Type'] != null) headers.set("Content-Type", String(args['Content-Type']))
if (JWSRequestSignaturePayment !== undefined) headers.set("Signature", JWSRequestSignaturePayment)

const url = `${baseUrl.replace(/\/+$/, '')}/callback${query.size > 0 ? `?${query}` : ''}`

const res = await fetchFn(url, {method: "POST", headers, body: JSON.stringify(args.body)})

if (!res.ok) throw new Error(`Request failed with status ${res.status}`, {cause: {status: res.status, body: await res.text()}})

return validateResponse(createApiCallbackResponse, await res.json())
};