FriendListMaintenance

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Scanner;

public class FriendListMaintenance {
    public static void main(String[] args) {

        Scanner scanner = new Scanner(System.in);

        String[] names = scanner.nextLine().split(", ");
        ArrayList<String> userNames = new ArrayList<>(Arrays.asList(names));

        int blacklistedCounter = 0;
        int lostCounter = 0;
        String input = scanner.nextLine();
        while (!input.equals("Report")) {
            String[] tokens = input.split(" ");
            String command = tokens[0];

            switch (command) {
                case "Blacklist":
                    String nameToContain = tokens[1];
                    for (int i = 0; i < userNames.size(); i++) {
                        if (userNames.get(i).equals(nameToContain)) {
                            System.out.printf("%s was blacklisted.%n", nameToContain);
                            userNames.set(i, "Blacklisted");
                            blacklistedCounter++;
                            break;
                        }
                    }
                    for (String userName : userNames) {
                        if (!userName.equals(nameToContain)) {
                            break;
                        } else {
                            System.out.printf("%s was not found.%n", nameToContain);
                        }
                    }

                    break;
                case "Error": {
                    int index = Integer.parseInt(tokens[1]);
                    if (index < 0 || index >= userNames.size()) {
                        break;
                    }
                    if (!userNames.get(index).equals("Blacklisted") && !userNames.get(index).equals("Lost")) {
                        System.out.printf("%s was lost due to an error.%n", userNames.get(index));
                        userNames.set(index, "Lost");
                        lostCounter++;
                    }
                    break;
                }
                case "Change":
                    int index = Integer.parseInt(tokens[1]);
                    String newName = tokens[2];
                    if (index < 0 || index >= userNames.size()) {
                        break;
                    } else {
                        for (int i = 0; i < userNames.size(); i++) {
                            if (i == index) {
                                System.out.printf("%s changed his username to %s.%n", userNames.get(i), newName);
                                break;
                            }
                        }
                        userNames.set(index, newName);
                    }

                    break;
            }
            input = scanner.nextLine();
        }
        System.out.println(String.format("Blacklisted names: %d", blacklistedCounter));
        System.out.println(String.format("Lost names: %d", lostCounter));
        System.out.println(String.join(" ", userNames));
    }
}