/**
 * Configure our database.
 * @module app/db/configure
 */

import _knex from "knex";
import _bookshelf from "bookshelf";
import jsonColumns from "bookshelf-json-columns";
import cascadeDelete from "bookshelf-cascade-delete";

import { knexfile } from "app/constants";
import { registerModels } from "app/db/models";

import { types } from "pg";

/**
 * PostgreSQL type conversion
 */
types.setTypeParser(types.builtins.INT8, (value) => parseInt(value));
types.setTypeParser(types.builtins.FLOAT8, (value) => parseFloat(value));
types.setTypeParser(types.builtins.NUMERIC, (value) => parseFloat(value));

/**
 * Memoized copies of the current knex and bookshelf objects.
 */
let knex, bookshelf;

/**
 * Configure a knex instance based on the knexfile.
 */
function configureKnex() {
  const environment = process.env.NODE_ENV ?? "development";

  if (!knexfile[environment]) {
    throw new Error("Please specify a valid NODE_ENV");
  }

  knex = _knex(knexfile[environment]);
  return knex;
}

/**
 * Configure knex and bookshelf. By default, memoizes the
 * knex object so other methods can call `configure()` and get it.
 * The database is configured this way to be interoperable with the test environment.
 *
 * @param {Object} __knex  An existing knex instance, mainly used in testing.
 */
export default function configure(__knex) {
  if (!knex || (__knex && knex !== __knex)) {
    knex = __knex || configureKnex();
    bookshelf = _bookshelf(knex);
    bookshelf.plugin(jsonColumns);
    bookshelf.plugin(cascadeDelete);
    registerModels(bookshelf);
  }
  return { bookshelf, knex };
}