refactor.js

'use strict';

class Expense {
  constructor(type, amount) {
    this.type = type;
    this.amount = amount;
  }
}

class ExpenseReport {
  constructor(expenses) {
    this.expenses = expenses;
    this.typeNames = {
      1: "Breakfast",
      2: "Lunch",
      3: "Dinner"
    };
  }

  getTotal() {
    return this.expenses.reduce((acc, expense) => acc + expense.amount, 0);
  }

  getMealExpenses() {
    return this.expenses.reduce((acc, expense) => {
      if (expense.type === 1 || expense.type === 3) {
        return acc + expense.amount;
      }
      return acc;
    }, 0);
  }

  getTypeName(type) {
    return this.typeNames[type];
  }

  getExpenseMarker(expense) {
    if (
      (expense.type === 3 && expense.amount > 100) ||
      (expense.type === 2 && expense.amount > 50) ||
      (expense.type === 1 && expense.amount > 20)
    ) {
      return "[over-expense!]";
    }
    return " ";
  }

  printReport() {
    console.info("Today Travel Expenses " + new Date().toISOString().slice(0, 10));

    for (const expense of this.expenses) {
      const expenseName = this.getTypeName(expense.type);
      const expenseMarker = this.getExpenseMarker(expense);
      console.info(expenseName + "\t" + expense.amount + "eur" + "\t" + expenseMarker);
    }

    console.info("Meal expenses: " + this.getMealExpenses() + "eur");
    console.info("Total expenses: " + this.getTotal() + "eur");
  }
}

// test cases
const expenses = [
  new Expense(1, 15.20),
  new Expense(1, 28.10),
  new Expense(2, 10.20),
  new Expense(3, 16.00),
  new Expense(3, 120.20)
];
const report = new ExpenseReport(expenses);
console.log(report.getTotal() === 189.7);
console.log(report.getMealExpenses() === 159.3);
console.log(report.getTypeName(1) === "Breakfast");
console.log(report.getTypeName(2) === "Lunch");
console.log(report.getTypeName(3) === "Dinner");
console.log(report.getExpenseMarker(new Expense(3, 120.20)) === "[over-expense!]");
report.printReport();