// Typed client for the anonymous menu API. It wraps an injected fetcher, so
// the Nuxt composable decides the base URL and headers and `node --test` can
// drive it with a stub.

import type { Menu, MenuEnvelope } from './types.ts'

/** Issues one GET for `path` (e.g. "/menus/main") with `query`, resolving the parsed JSON. */
export type MenuFetcher = (path: string, query?: Record<string, string>) => Promise<unknown>

/** True for a fetch error that carries HTTP status 404 (ofetch, h3 or plain). */
export function isNotFound(err: unknown): boolean {
  if (!err || typeof err !== 'object') return false
  const e = err as { status?: unknown; statusCode?: unknown; response?: { status?: unknown } }
  return e.status === 404 || e.statusCode === 404 || e.response?.status === 404
}

/** The API path of a menu: /menus/<code>, the code URL-encoded. */
export function menuPath(code: string): string {
  return `/menus/${encodeURIComponent(code)}`
}

export interface MenuClient {
  /** The menu with `code`, or null when the API answers 404 (unknown or inactive). */
  getMenu(code: string, locale?: string): Promise<Menu | null>
}

export function createMenuClient(fetcher: MenuFetcher): MenuClient {
  return {
    async getMenu(code, locale) {
      const query = locale ? { locale } : undefined
      let res: MenuEnvelope
      try {
        res = (await (query ? fetcher(menuPath(code), query) : fetcher(menuPath(code)))) as MenuEnvelope
      } catch (err) {
        if (isNotFound(err)) return null
        throw err
      }
      const menu = res?.data
      if (!menu || typeof menu !== 'object') return null
      return { ...menu, items: Array.isArray(menu.items) ? menu.items : [] }
    },
  }
}