/**
 * * Copyright (c) 2016, Intel Corporation.
 *
 * This program is licensed under the terms and conditions of the
 * Apache License, version 2.0.  The full text of the Apache License is at
 * http://www.apache.org/licenses/LICENSE-2.0
 */

"use strict";

/**
 * This class will instantiate the ORM, load in the models, call the method
 * to create db connections, test the connection, then create the tables and
 * relationships if not present
 */
const fs = require('fs'),
  path = require('path'),
  Sequelize = require('sequelize'),
  config = require('config');

function init() {
  const db = {
    sequelize: new Sequelize(config.get("db.host"), config.get("db.options"))
  };

  return new Promise(function(resolve, reject) {
    console.log("DB initialization beginning. DB access will block.");
    let models = [];

    /* Load models */
    fs.readdirSync(__dirname).forEach(function (file) {
      if (file == "." || file == ".." || file == "index.js") {
        return;
      }
      let model = db.sequelize.import(path.join(__dirname, file));
      db[model.name] = model;
      models.push(model);
    });

    /* After all the models are loaded, associate any that need it */
    models.forEach(function (model) {
      if (model.associate) {
        model.associate(db);
      }
    });

    return db.sequelize.authenticate().then(function () {
      console.log("Connection established successfully with DB.");
      return db.sequelize.sync({
        force: false
      }).then(function () {
        console.log("DB relationships successfully mapped. DB access unblocked.");
        return resolve(db);
      });
    }).catch(function (error) {
      console.log("ERROR: Failed to authenticate with DB");
      console.log("ERROR: " + JSON.stringify(config.get("db"), null, 2));
      console.log(error);
      return reject(error);
    });
  });
}

module.exports = init();