import {z} from 'zod'

export type GetApiStatsOptions = {baseUrl?: string | undefined, XFOAuth2?: string | undefined, fetch?: typeof fetch | undefined};

export const getApiStatsResponse = z.object({"totals[threads]": z.number().int().optional(), "totals[messages]": z.number().int().optional(), "totals[users]": z.number().int().optional(), "latest_user[user_id]": z.number().int().optional(), "latest_user[username]": z.string().optional(), "latest_user[register_date]": z.number().int().optional(), "online[total]": z.number().int().optional(), "online[members]": z.number().int().optional(), "online[guests]": z.number().int().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
};

/**
 * Get site statistics
 * 
 * GET /stats/
 * 
 * Also accepts auth: XF-Api-Key
 */
export const getApiStats = async (options?: GetApiStatsOptions) => {
const {baseUrl = "https://example.com/api", fetch: fetchFn = fetch, XFOAuth2} = options ?? {}

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

if (XFOAuth2 !== undefined) headers.set('authorization', `Bearer ${XFOAuth2}`)

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