import * as Hapi from "@hapi/hapi";
import * as Hoek from "@hapi/hoek";
import pgPromise from "pg-promise";
import * as pgMonitor from "pg-monitor";
import type { IConnectionParameters } from "pg-promise/typescript/pg-subset";
import type { IMain, IInitOptions } from "pg-promise";

import { IPGPPluginOptions, ExtendedProtocol } from "./types";

export * from "./types";
const defaultOptions: IPGPPluginOptions<unknown> = {
  connection: undefined,
  pgpInit: {},
  logSql: false,
  decorateAs: {
    pgp: "pgp",
    db: "db",
  },
};

export const startDiagnostics = <T>(
  logSql: boolean,
  initOpts: IInitOptions<T>
): void => {
  if (logSql) {
    pgMonitor.attach(initOpts);
  } else {
    pgMonitor.attach(initOpts, ["error"]);
  }
};

export const stopDiagnostics = (): void => pgMonitor.detach();

const startPgp = async <T>(initOptions: IInitOptions<T>): Promise<IMain> => {
  const pgp: IMain = pgPromise(initOptions);
  return pgp;
};

const startDb = async <T>(
  pgp,
  connection: string | IConnectionParameters
): Promise<ExtendedProtocol<T>> => {
  const db: ExtendedProtocol<T> = pgp(connection);

  return db;
};

const register = async <T>(
  server: Hapi.Server,
  userOpts?: IPGPPluginOptions<T>
): Promise<void> => {
  const options: IPGPPluginOptions<T> = Hoek.applyToDefaults(
    defaultOptions,
    userOpts
  ) as IPGPPluginOptions<T>;

  if (!options.connection) {
    throw new Error(
      "hapi-pg-promise: connection details are not defined. You must specify a valid connection for the plugin to boot."
    );
  }

  if ("pgp" in options && "pgpInit" in options) {
    throw new Error(
      "hapi-pg-promise: options pgp and pgpInit are mutually exclusive"
    );
  }

  let pgp: IMain;
  if ("pgp" in options) {
    pgp = options.pgp;
  } else {
    pgp = await startPgp(options.pgpInit);
    startDiagnostics(options.logSql, options.pgpInit);
  }

  const db = await startDb(pgp, options.connection);

  if (options.decorateAs) {
    if (options.decorateAs) {
      server.decorate("request", options.decorateAs.pgp, pgp);
      server.decorate("server", options.decorateAs.pgp, pgp);
    }

    if (options.decorateAs.db) {
      server.decorate("server", options.decorateAs.db, () => db);
      server.decorate("request", options.decorateAs.db, () => db);
    }
  }

  server.ext("onPostStop", async () => {
    stopDiagnostics();
    await db.$pool.end();
  });
};

const pgPromisePlugin = {
  register,
  name: "pg-promise",
  version: "0.0.1",
};

export default pgPromisePlugin;