/* 
 * A program to perform some basic operations on a list of Strings 
 * using Java streams. 
 */

package arraylists;

import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

public class StreamArrayListProcessing {

    public static void main(String[] args) {
        // POINT A: Add some strings which represent names to an ArrayList.
        List<String> names = new ArrayList<>();
        names.add("Holiday, Billie");
        names.add("Claudel, Camille");
        names.add("Picasso, Pablo");
        names.add("Gallen-Kallela, Akseli");
        names.add("Zotto, Osvaldo");

        names.add("Eugen, Prinz");
        names.add("Hipper, Admiral");
        names.add("HMS, Amazon");

        // POINT B: Use map and the toList collector to create an ArrayList of just the first names of the names ArrayList.
        //          Use a for loop to print out the names. separated by spaces.
        List<String> firstNamesList = names.stream()
                .map(n -> firstName(n))
                .collect(Collectors.toList());

        System.out.print("First names: ");
        for (String firstName : firstNamesList) {
            System.out.print(firstName + " ");
        }
        System.out.println();

        // POINT C: Use map and the joining collector to create a String of just the first names of the names ArrayList
        //          with each names separated by a comma. Print it.
        String firstNames = names.stream()
                .map(n -> firstName(n))
                .collect(Collectors.joining(", "));

        System.out.println("First names: " + firstNames);

        // POINT D: By analogy from point C, print a comma-separated list of the last names in the names ArrayList.
        String lastNames = names.stream()
                .map(n -> lastName(n))
                .collect(Collectors.joining(", "));

        System.out.println("Last names: " + lastNames);

        // POINT E: Print a comma-separated list of all uppercase first names from the list of names in the names ArrayList.
        String upperCaseFirstNames = names.stream()
                .map(n -> firstName(n))
                .map(n -> n.toUpperCase())
                .collect(Collectors.joining(", "));

        System.out.println("Uppercase first names: " + upperCaseFirstNames);

        // POINT F: Print a comma-separated list of all hyphenated last names from the list of names in the names ArrayList.
        String hyphenatedLastNames = names.stream()
                .map(n -> lastName(n))
                .filter(n -> n.contains("-"))
                .collect(Collectors.joining(", "));

        System.out.println("Hyphenated last names: " + hyphenatedLastNames);

        // POINT G: Print the integer value of the total length of all names in the names ArrayList.
        int totalLength = names.stream()
                .map(n -> n.length())
                .reduce(0, (n1, n2) -> n1 + n2);

        System.out.println("Total length: " + totalLength);

        // POINT H: Print the integer value of the product of the length of all first names in the names ArrayList.
        int firstLength = names.stream()
                .map(n -> firstName(n).length())
                .reduce(0, (n1, n2) -> n1 + n2);

        System.out.println("First name total length: " + firstLength);

        // POINT I: Print the integer value of the product of the length of all first names in the names ArrayList.
        int productLength = names.stream()
                .map(n -> n.length())
                .reduce(1, (n1,n2) -> n1 * n2);

        System.out.println("Product of the lengths of the names: " + productLength);

    }

    private static String firstName(String directoryStyleName) {
        int firstNamePosition = directoryStyleName.indexOf(",");
        String firstName = directoryStyleName.substring(firstNamePosition + 2, directoryStyleName.length());
        return firstName;
    }

    private static String lastName(String directoryStyleName) {
        int lastNamePosition = directoryStyleName.indexOf(",");
        String lastName = directoryStyleName.substring(0, lastNamePosition);
        return lastName;
    }
}