app.js

//Budget Controller MODEL
var budgetController = (function () {

    var Expense = function (id, description, value) {
        this.id = id;
        this.description = description;
        this.value = value;
        this.percentage = -1;
    };

    Expense.prototype.calcPercentages = function (totalIncome) {

        if (totalIncome > 0) {
            this.percentage = Math.round((this.value / totalIncome) * 100);
        } else {
            this.percentage = -1;
        }
    };

    Expense.prototype.getPercentage = function () {
        return this.percentage;
    };

    var Income = function (id, description, value) {
        this.id = id;
        this.description = description;
        this.value = value;
    };

    var calculateTotal = function (type) {

        var sum = 0;
        data.allItems[type].forEach(function (current) {
            sum += current.value;
        });

        data.totals[type] = sum;
    };

    var data = {
        allItems: {
            exp: [],
            inc: []
        },
        totals: {
            exp: 0,
            inc: 0
        },
        budget: 0,
        percentage: -1
    }

    // type= income or expense, des = description, val = value
    return {
        addItem: function (type, des, val) {
            var newItem, ID;

            //Create new ID.
            if (data.allItems[type].length > 0) {
                ID = data.allItems[type][data.allItems[type].length - 1].id + 1;
            } else {
                ID = 0;
            }

            // Create new Item based on 'inc' or 'exp'.
            if (type === 'exp') {
                newItem = new Expense(ID, des, val);
            } else if (type === 'inc') {
                newItem = new Income(ID, des, val);
            }


            // Push it into our data structure
            data.allItems[type].push(newItem);

            // Return the new element
            return newItem;

        },

        deleteItem: function (type, id) {
            var ids, index;

            ids = data.allItems[type].map(function (current) {
                return current.id;
            });
            // returns the index of the ids
            index = ids.indexOf(id);

            // if index does not exist it will show -1
            if (index !== -1) {
                data.allItems[type].splice(index, 1);
            }

        },

        calculateBudget: function () {

            // calculate total income and expenses
            calculateTotal('exp');
            calculateTotal('inc');

            // calculate the budget: income - expenses
            data.budget = data.totals.inc - data.totals.exp;

            // calculate the percentage of income that we spent
            if (data.totals.inc > 0) {
                data.percentage = Math.round((data.totals.exp / data.totals.inc) * 100);
            } else {
                data.percentage = -1;
            }

            // Expense = 100 and income 300, spent 33.333% = 100/300 = 0.333 * 100

        },

        calculatePercentages: function () {

            data.allItems.exp.forEach(function (cur) {
                cur.calcPercentages(data.totals.inc);
            });
        },

        getPercentage: function () {
            var allPerc = data.allItems.exp.map(function (cur) {
                return cur.getPercentage();
            });
            return allPerc;
        },


        getBudget: function () {
            return {
                budget: data.budget,
                totalInc: data.totals.inc,
                totalExp: data.totals.exp,
                percentage: data.percentage
            };

        },

        testing: function () {
            console.log(data);
        }
    };

})();

// UI Controller MODEL
var UIController = (function () {

    var DOMstrings = {
        inputType: '.add__type',
        inputDescription: '.add__description',
        inputValue: '.add__value',
        inputBtn: '.add__btn',
        incomeContainer: '.income__list',
        expensesContainer: '.expenses__list',
        budgetLabel: '.budget__value',
        incomeLabel: '.budget__income--value',
        expenseLabel: '.budget__expenses--value',
        percentageLabel: '.budget__expenses--percentage',
        container: '.container',
        expensesPercLabel: '.item__percentage',
        dateLabel: '.budget__title--month'
    };

    var formatNumber = function (num, type) {
        var numSplit, int, dec, sign;
        /**
         + or - before the number 
         exactly 2 decimal points
         comma seperating the thousands
         */
        num = Math.abs(num);
        // toFixed() is a method of the number prototype and handleds the decimal points 
        num = num.toFixed(2);

        numSplit = num.split('.')

        int = numSplit[0];
        if (int.length > 3) {
            int = int.substr(0, int.length - 3) + ',' + int.substr(int.length - 3, 3);
        }
        dec = numSplit[1];

        return (type === 'exp' ? '-' : '+' + ' ') + int + '.' + dec;

    };

    var nodeListForEach = function (list, callback) {
        for (var i = 0; i < list.length; i++) {
            callback(list[i], i);
        }
    };

    return {
        getInput: function () {

            return {
                type: document.querySelector(DOMstrings.inputType).value, // will be either inc or exp
                description: document.querySelector(DOMstrings.inputDescription).value,
                //convert a String to a float value.
                value: parseFloat(document.querySelector(DOMstrings.inputValue).value)
            };
        },

        addListItem: function (obj, type) {

            var html, newHtml;
            // Create HTML string with placeholder text

            if (type === 'inc') {
                element = DOMstrings.incomeContainer;
                html = '<div class="item clearfix" id="inc-%id%"><div class="item__description">%description%</div>' +
                    '<div class="right clearfix"><div class="item__value">%value%</div><div class="item__delete">' +
                    '<button class="item__delete--btn"><i class="ion-ios-close-outline"></i></button></div></div></div>';

            } else if (type === 'exp') {
                element = DOMstrings.expensesContainer;
                html = '<div class="item clearfix" id="exp-%id%"><div class="item__description">%description%</div>' +
                    '<div class="right clearfix"><div class="item__value">%value%</div><div class="item__percentage">21%</div>' +
                    '<div class="item__delete"><button class="item__delete--btn"><i class="ion-ios-close-outline"></i></button></div></div></div>';

            }

            // Replace the placeholder text with some actual data
            newHtml = html.replace('%id%', obj.id);
            newHtml = newHtml.replace('%description%', obj.description);
            newHtml = newHtml.replace('%value%', formatNumber(obj.value, type));

            // Insert the HTML into the DOM
            document.querySelector(element).insertAdjacentHTML('beforeend', newHtml);
        },

        deleteListItem: function (selectorId) {
            var el;
            el = document.getElementById(selectorId);
            el.parentNode.removeChild(el);
        },

        clearFields: function () {
            var fields, fieldsArray;
            fields = document.querySelectorAll(DOMstrings.inputDescription + ',' + DOMstrings.inputValue);
            //querySelectorALL returns a List. We have to convert the List to an Array.
            fieldsArray = Array.prototype.slice.call(fields);

            //in an forEach Loop the anonomus function can recieve up to three arguments
            fieldsArray.forEach(function (current, index, array) {
                current.value = "";
            })

            fieldsArray[0].focus();
        },

        displayBudget: function (obj) {
            var type;
            obj.budget > 0 ? type = 'inc' : type = 'exp';

            document.querySelector(DOMstrings.budgetLabel).textContent = formatNumber(obj.budget, type);
            document.querySelector(DOMstrings.incomeLabel).textContent = formatNumber(obj.totalInc, 'inc');
            document.querySelector(DOMstrings.expenseLabel).textContent = formatNumber(obj.totalExp, 'exp');

            if (obj.percentage > 0) {
                document.querySelector(DOMstrings.percentageLabel).textContent = obj.percentage + '%';
            } else {
                document.querySelector(DOMstrings.percentageLabel).textContent = '---';
            }

        },

        displayPercentages: function (percantages) {

            var fields = document.querySelectorAll(DOMstrings.expensesPercLabel);

            nodeListForEach(fields, function (current, index) {
                if (percantages[index] > 0) {
                    current.textContent = percantages[index] + '%';
                } else {
                    current.textContent = percantages[index] + '---';
                }
            });
        },

        displayMonth: function () {
            var now, year, month;

            now = new Date();

            months = ['Januar', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'];
            month = now.getMonth();
            year = now.getFullYear();
            document.querySelector(DOMstrings.dateLabel).textContent = months[month] + ' ' + year;
        },

        changedType: function () {

            var fields = document.querySelectorAll(
                DOMstrings.inputType + ',' +
                DOMstrings.inputDescription + ',' +
                DOMstrings.inputValue);

                nodeListForEach(fields, function(cur){
                    cur.classList.toggle('red-focus');
                });

                document.querySelector(DOMstrings.inputBtn).classList.toggle('red');

        },

        getDOMstrings: function () {
            return DOMstrings;
        }

    };

})();


// Global APP Controller. Is used to interact between BudgetController og UI Controller
var controller = (function (budgetCtrl, UICtrl) {

    var setupEventListeners = function () {
        var DOM = UICtrl.getDOMstrings();
        // instead of clickink with the mouse we use the 'keypress' function to add to the budget
        // the word 'event' is an random word. You can use any other word.
        // the which property is for older browsers
        document.querySelector(DOM.inputBtn).addEventListener('click', ctrlAddItem);
        document.addEventListener('keypress', function (event) {
            if (event.keyCode === 13 || event.which === 13) {
                ctrlAddItem();
            }
        });

        document.querySelector(DOM.container).addEventListener('click', ctrlDeleteItem);

        document.querySelector(DOM.inputType).addEventListener('change', UICtrl.changedType);
    };

    var updateBudget = function () {

        // 1. Calculate the budget
        budgetCtrl.calculateBudget();

        // 2. Return the budget
        var budget = budgetCtrl.getBudget();

        // 3. Display the budget on the UI
        UICtrl.displayBudget(budget);
    };

    var updatePercentages = function () {

        // 1. calculate the percentages
        budgetCtrl.calculatePercentages();
        // 2. Read percentages from the budget controller
        var percentages = budgetCtrl.getPercentage();
        // 3. Update the UI with the new percentages
        UICtrl.displayPercentages(percentages);
    };


    var ctrlAddItem = function () {

        var input, newItem;

        // 1. Get the field Input data
        input = UICtrl.getInput();

        if (input.description !== "" && !isNaN(input.value) && input.value > 0) {
            // 2. Add the item to the budget controller
            newItem = budgetCtrl.addItem(input.type, input.description, input.value);

            // 3. Add the new Item to the UI
            UICtrl.addListItem(newItem, input.type);

            // 4. Clear the fields
            UICtrl.clearFields();

            // 5. Calculate and update Buget
            updateBudget();

            // 6. Calculate and update percantages
            updatePercentages();
        }
    };


    var ctrlDeleteItem = function (event) {
        var itemID, splitID, type, ID;

        itemID = event.target.parentNode.parentNode.parentNode.parentNode.id;

        if (itemID) {

            //inc-1
            splitID = itemID.split('-');
            type = splitID[0];
            ID = parseInt(splitID[1]);

            // 1. Delete the item from the data structure
            budgetCtrl.deleteItem(type, ID);

            // 2. Delete the item from the UI
            UICtrl.deleteListItem(itemID);

            // 3. Update and show the new budget
            updateBudget();

            // 4. Calculate and update percantages
            updatePercentages();
        }
    };

    return {
        init: function () {
            console.log('Aplication has started');
            UICtrl.displayMonth();
            UICtrl.displayBudget(
                {
                    budget: 0,
                    totalInc: 0,
                    totalExp: 0,
                    percentage: -1
                }
            );
            setupEventListeners();
        }
    };

})(budgetController, UIController);


controller.init();