@better-auth-ui/core/src/lib/create-auth-plugin.ts

Authentication components and data utilities for [Better Auth](https://better-auth.com), available for React and Solid.

import type { AuthPlugin } from "./auth-plugin"

/**
 * Creates a plugin factory and attaches its `id` as a static property so
 * consumers (e.g. `useAuthPlugin`) can look it up without invoking the
 * factory.
 *
 * @example
 * ```ts
 * export const themePlugin = createAuthPlugin(
 *   "theme",
 *   (options: ThemePluginOptions) => ({
 *     setTheme: options.setTheme,
 *     themes: options.themes ?? ["system", "light", "dark"]
 *   })
 * )
 * ```
 */
export function createAuthPlugin<
  const TId extends string,
  TArgs extends unknown[],
  TResult extends Omit<AuthPlugin, "id"> & object
>(id: TId, factory: (...args: TArgs) => TResult) {
  const wrapped = (...args: TArgs): TResult & { id: TId } => {
    const plugin = { ...factory(...args), id }
    const options = args[0]
    const localizationOverrides =
      options && typeof options === "object" && "localization" in options
        ? (options.localization as Record<string, unknown> | undefined)
        : undefined

    if (localizationOverrides) {
      Object.defineProperty(plugin, "_localizationOverrides", {
        configurable: false,
        enumerable: false,
        value: localizationOverrides
      })
    }

    return plugin
  }

  return Object.assign(wrapped, { id })
}