// CSE 143, Winter 2009, Marty Stepp
// Homework 3: Stable Marriage
//
// This program runs the stable marriage simulation and prints the results.
// It reads and sets up the input data for all the men and women that will
// be passed in to your MatchMaker object.

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

public class StableMarriageMain {
    public static void main(String[] args) throws FileNotFoundException {
        // prompt for input file name
        Scanner console = new Scanner(System.in);
        System.out.println("Welcome to the CSE 143 Stable Marriage simulator!");
        System.out.print("Input file name? ");
        String filename = console.nextLine();
        
        // read data from input file
        Scanner input = new Scanner(new File(filename));
        Set<Person> men = new TreeSet<Person>();
        Set<Person> women = new TreeSet<Person>();
        readInput(input, men, women);

        // prompt for rounds
        System.out.print("How many rounds (0 to repeat until stable)? ");
        int rounds = console.nextInt();
        System.out.println();
        
        // do match-making and print results
        MatchMaker maker = new MatchMaker(men, women);
        while (true) {
            if (rounds == 0) {
                if (maker.isStable()) {
                    break;
                }
            } else if (maker.getRound() >= rounds) {
                break;
            }
            
            maker.nextMatchRound();
            System.out.println("Round " + maker.getRound());
            System.out.println(maker);
        }
        
        if (maker.isStable()) {
            System.out.println(maker.getRound() + " rounds performed and stable state reached.");
        } else {
            System.out.println(maker.getRound() + " rounds performed but none were stable.");
        }
    }
    
    // Reads the input from the given file and puts it into the two given sets.
    public static void readInput(Scanner input, Set<Person> men, Set<Person> women) {
        Set<Person> listToUse = men;

        while (input.hasNextLine()) {
            // read a person's info
            String line = input.nextLine();
            if (line.startsWith("#")) {
                // this is a comment line in the file; ignore it
            } else if (line.length() == 0) {
                listToUse = women;
            } else {
                Scanner lineScan = new Scanner(line);
                lineScan.useDelimiter("[:,]");
                String name = lineScan.next();
                Person person = new Person(name);
                while (lineScan.hasNext()) {
                    String partner = lineScan.next();
                    person.getPreferences().add(partner);
                    person.getRankings().put(partner, person.getPreferences().size());
                }
                listToUse.add(person);
            }
        }
        
        // let's verify that the file has valid data
        for (Person man : men) {
            verifyPerson(man, women, men, women);
        }
        for (Person woman : women) {
            verifyPerson(woman, men, men, women);
        }
    }
    
    // makes sure this person's data from the file is mostly valid
    private static void verifyPerson(Person person, Set<Person> oppositeSex,
            Set<Person> men, Set<Person> women) {
        // make sure this person has some ranking for each member of opposite sex
        for (Person mate : oppositeSex) {
            if (!person.getRankings().containsKey(mate.getName())) {
                throw new RuntimeException(person.toStringLong() + 
                        " does not contain a ranking for " + mate.getName() + 
                        "\nmen  : " + men + "\nwomen: " + women);
            }
        }
        
        // make sure there are not the wrong number of rankings/prefs
        if (person.getPreferences().size() != oppositeSex.size()) {
            throw new RuntimeException(person.toStringLong() + " has " + 
                    person.getPreferences().size() + " preferences but should have " +
                    oppositeSex.size() + "\nmen  : " + men + "\nwomen: " + women);
        }
        if (person.getRankings().keySet().size() != oppositeSex.size()) {
            throw new RuntimeException(person.toStringLong() + " has " + 
                    person.getPreferences().size() + " rankings but should have " + 
                    oppositeSex.size() + "\nmen  : " + men + "\nwomen: " + women);
        }
    }
}