dataHandler.js

'use strict';

let csv = require("csvtojson");

let ingredientsDataName = "ingredients";
let transactionsDataName = "transactions";
let defaultLanguage = "en";

// Store data in an object to keep the global namespace clean
function Data() {
  this.data = {};
  this.orders = {};
  this.currentOrderNumber = 0;
}

Data.prototype.getUILabels = function (lang) {
  var ui = require("./data/ui_" + (lang || defaultLanguage) + ".json");
  return ui;
};

/*
  Returns a JSON object array of ingredients with the fields from
  the CSV file, plus a calculated amount in stock, based on
  transactions.
*/
Data.prototype.getIngredients = function () {
  var d = this.data;
  return d[ingredientsDataName].map(function (obj) {
    obj.stock = d[transactionsDataName].reduce(function (sum, trans) {
      if (trans.ingredient_id === obj.ingredient_id) {
        return sum + trans.change;
      } else {
        return sum;
      }
    }, 0);
    return obj;
  });
};

/*
  Function to load initial data from CSV files into the object
*/
Data.prototype.initializeTable = function (table) {
  csv({checkType: true})
    .fromFile("./data/" + table + ".csv")
    .then((jsonObj) => {
      //console.log("JSON object", jsonObj, "done");
      this.data[table] = jsonObj;
    });
};

Data.prototype.initializeData = function() {
  console.log("Starting to build data tables");
  // Load initial ingredients. If you want to add columns, do it in the CSV file.
  this.initializeTable(ingredientsDataName);
  // Load initial stock. Make alterations in the CSV file.
  this.initializeTable(transactionsDataName);
}
/*
  Adds an order to to the queue and makes an withdrawal from the
  stock. If you have time, you should think a bit about whether
  this is the right moment to do this.
*/

Data.prototype.getOrderNumber = function () {
  this.currentOrderNumber += 1;
  return this.currentOrderNumber;
}

Data.prototype.addOrder = function (order) {
  var orderId = this.getOrderNumber();
  this.orders[orderId] = order.order;
  this.orders[orderId].orderId = orderId;
  this.orders[orderId].status = "not-started";
  var transactions = this.data[transactionsDataName],
    //find out the currently highest transaction id
    transId =  transactions[transactions.length - 1].transaction_id,
    i = order.order.ingredients,
    k;
  for (k = 0; k < i.length; k += 1) {
    transId += 1;
    transactions.push({transaction_id: transId,
                       ingredient_id: i[k].ingredient_id,
                       change: - 2});
  }
    return orderId;
};

Data.prototype.changeStock = function (item, saldo) {
  var transactions = this.data[transactionsDataName]
  var transId = transactions[transactions.length - 1].transaction_id
  transactions.push({transaction_id: transId,
                     ingredient_id: item.ingredient.ingredient_id,
                     change: saldo - item.ingredient.stock});
};

Data.prototype.getAllOrders = function () {
  return this.orders;
};

Data.prototype.markOrderDone = function (orderId) {
  this.orders[orderId].status = "done";
};

Data.prototype.markOrderStarted = function (orderId) {
  this.orders[orderId].status = "started";
};

Data.prototype.markOrderNotStarted = function (orderId) {
  this.orders[orderId].status = "not-started";
};

module.exports = Data;