import {z} from 'zod'

export type CustomerTypeFilter = 'individual' | 'business';

export type GetApiV1CustomersArgs = {reference?: string | undefined, customer_type?: CustomerTypeFilter | undefined, cursor?: (string | null) | undefined, page_size?: number | undefined};

export type GetApiV1CustomersOptions = {baseUrl?: string | undefined, fetch?: typeof fetch | undefined};

export const approvalStatus = z.enum(["auto_approved", "pending", "approved", "rejected"]);

export const customerTypeFilter = z.enum(["individual", "business"]);

export const customerSummary = z.object({approval_status: approvalStatus, created_at: z.string(), customer_type: customerTypeFilter, display_name: z.string(), id: z.string(), reference: z.string().max(36)});

export const cursorString = z.object({next: z.string().nullable().optional(), size: z.number().int().gte(0)});

export const listCustomersResponse = z.object({customers: z.array(customerSummary), pages: cursorString});

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 customers
 * 
 * GET /v1/customers
 */
export const getApiV1Customers = async (args: GetApiV1CustomersArgs, options?: GetApiV1CustomersOptions) => {
const {baseUrl = "https://auth-sandbox.fuse.me", fetch: fetchFn = fetch} = options ?? {}

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

if (args.reference != null) query.append("reference", String(args.reference))
if (args.customer_type != null) query.append("customer_type", String(args.customer_type))
if (args.cursor != null) query.append("cursor", String(args.cursor))
if (args.page_size != null) query.append("page_size", String(args.page_size))

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