import { createInstance as createMFInstance } from "@module-federation/runtime";
import type { UserOptions } from "@module-federation/runtime/types";

import type { MakeOptional } from "../types";

/**
 * @public
 */
export type FederationRemote = {
  name: string;
  entry: string;
};

/**
 * @public
 */
export type CreateInstanceOptions = MakeOptional<
  Pick<UserOptions, "name" | "remotes" | "shared" | "plugins">,
  "remotes" | "plugins"
>;

/**
 * @public
 */
export interface FederationInstance {
  registerRemotes(remotes: FederationRemote[]): void;
  loadRemote<T>(id: string): Promise<T | null>;
}

/**
 * @public
 */
export function createInstance(
  options: CreateInstanceOptions,
): FederationInstance {
  const instance = createMFInstance({
    remotes: [],
    ...options,
  });

  return {
    registerRemotes: (remotes) =>
      instance.registerRemotes(remotes, { force: false }),
    loadRemote: async <T>(id: string) => {
      let remoteModule: T | null;

      try {
        remoteModule = await instance.loadRemote<T>(id);
      } catch (error) {
        throw new Error(`Failed to load remote module "${id}"`, {
          cause: error,
        });
      }

      return remoteModule;
    },
  };
}