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import java.util.*;

public class Main
{
    static String[] categories = {"toy", "car",  "candies", "cake", "milk", "fish", "apple", "watermelon" };

    public static void main(String[] args) {
        /*StockService stock = new Stock();
        stock.generateProducts();
        stock.print();*/

        Stock stock = new Stock(Currency.Grn);
        stock.generateProducts();
        stock.print();

        Wallet wallet = new Wallet(10, Currency.Dollars);
        wallet.print();

        Basket basket = new Basket();
        basket.putRandomItemsFromStock(stock);

        System.out.println("=== BUY ===");
        List<Product> successed = wallet.transaction(basket);
        System.out.println("=== END - BUY ===");

        wallet.print();
    }

    static class Basket {
        List<Product> toBuy;

        Basket() {
            toBuy = new ArrayList();
        }

        void putRandomItemsFromStock(Stock stockService) {
            List<Product> products = stockService.getAll();

            for (int i = 0; i < products.size(); i++) {
                if (Generator.bool()) {
                    toBuy.add(products.get(i));
                }
            }
        }

        List<Product> getAll() {
            return toBuy;
        }
    }

    static class Money {
        double value;
        Currency currency;

        Money(double value, Currency currency) {
            this.value = value;
            this.currency = currency;
        }
    }

    static class Wallet {
        double money;
        Currency currency;

        Wallet(double money, Currency currency) {
            this.money = money;
            this.currency = currency;
        }

        Wallet(Wallet wallet) {
            this.money = wallet.money;
            this.currency = wallet.currency;
        }

        List<Product> transaction(Basket basket) {
            List<Product> buyedProducts = new ArrayList();
            List<Product> basketProducts = basket.getAll();

            for (int i = 0; i < basketProducts.size(); i++) {
                if (this.transaction(basketProducts.get(i).price, basketProducts.get(i).category))
                    buyedProducts.add(basketProducts.get(i));
            }

            return buyedProducts;
        }

        boolean transaction(Money money, String name) {
            double tmpMoney = this.money;

            tmpMoney -= this.currency == money.currency ?
                money.value
                :
                currency.getDependence(money.currency) * money.value;

            if (tmpMoney > -1) {
                this.money = tmpMoney;

                System.out.println("=== TRANSACTION ===\nPrice: " + money.value + "\nResult: " + this.money + "\n -- Name: " + name);

                return true;
            }

            return false;
        }

        boolean transaction(Money money) {
            double tmpMoney = this.money;

            tmpMoney -= this.currency == money.currency ?
                money.value
                :
                currency.getDependence(money.currency) * money.value;

            if (tmpMoney > -1) {
                this.money = tmpMoney;

                System.out.println("======= TRANSACTION ======\nPrice: " + money.value + "\nResult: " + this.money);

                return true;
            }

            return false;
        }

        Wallet convert(Currency convertTo) {
            Wallet oldWallet = new Wallet(this);

            this.money *= currency.getDependence(convertTo);
            this.currency = convertTo;

            System.out.println("===== CONVERT =====\n" + oldWallet.money + " " + oldWallet.currency + " in " + convertTo + " = " + this.money + convertTo.flag + "\n");

            return this;
        }

        void print() {
            System.out.println(this);
        }

        @Override
        public String toString() {
            return "===== WALLET ======\nMoney: " + money + "\nCurrency: " + currency;
        }
    }

    enum Currency {
        Euro("eur", 1.10, 0.014, 0.038),
        Dollars("$", 0.90909090909, 0.016, 0.042),
        Rub("rub", 70.93, 63.98, 2.67),
        Grn("grn", 26.53, 23.89, 0.37);

        String flag;
        double[] dependency;

        Currency(String flag, double... dependency) {
            this.flag = flag;
            this.dependency = dependency;
        }

        double getDependence(Currency a) {
            int index = a.ordinal() -
                    (ordinal() == 0 || (a.ordinal() > ordinal() && ordinal() != dependency.length) ? 1 : 0);

            return dependency[index];
        }
    }

    interface StockService {
        StockService generateProducts();
        List<Product> getAll();
        void print();
    }

    static class Stock {
        List<Product> products;
        Currency currOfProducts;

        Stock(Currency currOfProducts) {
            products = new ArrayList();

            this.currOfProducts = currOfProducts;
        }

        Stock generateProducts() {
            int col = Generator.generateNumber(6) + 3;
            for (int i = 0; i < col; i++)  {
                products.add(new Product(
                    Generator.generateName(),
                    categories[Generator.generateNumber(categories.length)],
                    Generator.generateNumber(5) + 1,
                    new Money(Generator.generateNumber(100) + 20,
                            currOfProducts)));
            }

            return this;
        }

        List<Product> getAll() {
            return products;
        }

        void print() {
            System.out.println(getStockName(82));
            System.out.println(generateProductDescription());
            for (Product product : products) {
                System.out.println(product);
            }
        }

        void print(List<Product> products) {
            System.out.println(getStockName(82));
            System.out.println(generateProductDescription());
            for (Product product : products) {
                System.out.println(product);
            }
        }

        private String getStockName(int length) {
            String data = "Stock";
            StringBuilder builderFill = new StringBuilder();

            for (int i = 0; i < (length - data.length() - 2) / 2; i++) {
                builderFill.append("=");
            }

            String fill = builderFill.toString();

            return fill + ((length - data.length()) % 2 == 0 ? "" : " ") + " " + data + " " + fill;
        }

        private String generateProductDescription() {
            StringBuilder lineBuilder = new StringBuilder();

            lineBuilder.append(generateDataField("ID", 10));
            lineBuilder.append(generateDataField("NAME", 14));
            lineBuilder.append(generateDataField("CATEGORY", 16));
            lineBuilder.append(generateDataField("MASS", 12));
            lineBuilder.append(generateDataField("PRICE", 12));
            lineBuilder.append(generateDataField("CURRENCY", 12));

            return lineBuilder.toString();
        }

        private String generateDataField(String data, int length) {
            StringBuilder builderFill = new StringBuilder();

            for (int i = 0; i < (length - data.length() - 6) / 2; i++) {
                builderFill.append(" ");
            }

            String fill = builderFill.toString();

            return fill + ((length - data.length()) % 2 == 0 ? "" : " ") + " - " + data + " - " + fill + " ";
        }
    }

    static class Product {
        int id;
        String name;
        String category;
        double mass;
        /*double price;
        Currency currency;*/
        Money price;
        //double col;

        Product() { }

        Product(int id, String name, String category, double mass, Money price) {//double price) {//, double col) {
            this.id = id;
            this.name = name;
            this.category = category;
            this.mass = mass;
            this.price = price;
            //this.col = col;
        }

        Product(String name, String category, double mass, Money price) {//double price, Currency currency) {//, double col) {
            this.id = Generator.generateId();
            this.name = name;
            this.category = category;
            this.mass = mass;
            this.price = price;
            //this.col = col;
        }

        private String toString(int number, int length) {
            return toString(String.valueOf(number), length);
        }

        private String toString(double number, int length) {
            return toString(String.valueOf(number), length);
        }

        private String toString(String data, int length) {
            StringBuilder builderFill = new StringBuilder();

            for (int i = 0; i < (length - data.length()) / 2; i++) {
                builderFill.append(" ");
            }

            String fill = builderFill.toString();

            return fill + ((length - data.length()) % 2 == 0 ? "" : " ") + data + fill;
        }

        @Override
        public String toString() {
            return toString(id, 10) + "|" +
                    toString(name, 14) + "|" +
                    toString(category, 16) + "|" +
                    toString(mass, 12) + "|" +
                    toString(price.value, 12) + "|" +
                    toString(String.valueOf(price.currency), 12);
        }
    }

    static class Generator {
        static Random random;

        static {
            random = new Random();
        }

        static int generateInt() {
            return random.nextInt(Short.MAX_VALUE * 2 + 1) - Short.MAX_VALUE;
        }

        static int generateId() {
            return random.nextInt(Short.MAX_VALUE);
        }

        static int generateNumber(int upscale)  {
            return random.nextInt(upscale);
        }

        static char generateLetter() {
            int letter = generateNumber(25);

            return (char) (97 + letter);
        }

        static boolean bool() {
            return random.nextBoolean();
        }

        static String generateName() {
            StringBuilder builder = new StringBuilder();

            int length = generateNumber(4) + 6;
            for (int i = 0; i < length; i++) {
                builder.append(generateLetter());
            }

            return builder.toString();
        }
    }
}