import { type FastifyInstance } from 'fastify'
import fp from 'fastify-plugin'
import { type WorkerUtils, makeWorkerUtils } from 'graphile-worker'

type Options = {
  connectionString: string;
}


export interface ExtendedFastifyInstance extends FastifyInstance {
  graphile?: WorkerUtils
}

async function graphileWorkerPlugin (fastify: ExtendedFastifyInstance, opts: Options) {
  if (!fastify.graphile) {
    if (!opts.connectionString) throw new Error('graphileWorkerPlugin requires connectionString passed in options argument, but it was missing');
    const workerUtils = await makeWorkerUtils({ connectionString: opts.connectionString })
    fastify.decorate('graphile', workerUtils)
  }
}

export default fp(graphileWorkerPlugin)