// Hunter Schafer, CSE 143
// Prompts the user for two names and prints how distant of friends they are.
// This version fixes a couple of bugs.

import java.util.*;
import java.io.*;

public class Friends {

    public static void main(String[] args) throws FileNotFoundException {
        Scanner input = new Scanner(new File("friends.dot"));
        Map<String, Set<String>> friends = readFile(input);

        for (String person : friends.keySet()) {
            System.out.println(person + " " + friends.get(person));
        }
    }

    // pre : Assumes the given input is set to read a valid GraphViz file
    // post: Records all of the friendships listed in the given file and returns
    // it as a Map where the keys are each person, and the values are the set of all
    // their friends. Friendships are bi-directional so every record of "A is friends with B"
    // will also have an added "B is friends with A"
    public static Map<String, Set<String>> readFile(Scanner input) {
        Map<String, Set<String>> friends = new TreeMap<String, Set<String>>();

        while (input.hasNextLine()) {
            String line = input.nextLine();
            if (line.contains("--")) {
                Scanner lineData = new Scanner(line);
                String name1 = lineData.next();
                lineData.next(); // skip "--"
                String name2 = lineData.next();

                addFriendship(friends, name1, name2);
                addFriendship(friends, name2, name1);
            }
        }
        return friends;
    }

    // Adds name2 to the friends for name1 (creating a new set of friends if name1 has none)
    public static void addFriendship(Map<String, Set<String>> friends, String name1, String name2) {
        if (!friends.containsKey(name1)) {
            Set<String> theFriends = new TreeSet<String>();
            theFriends.add(name2);
            friends.put(name1, theFriends);
        } else {
            Set<String> theFriends = friends.get(name1);
            theFriends.add(name2);
            // Hunter: Not necessary, because the value (the reference to the set)
            // is already in the map!
            // friends.put(name1, theFriends);
        }
    }
}