// CSE 373 Homework 1: Stable Marriage
// YOU SHOULD NOT MODIFY THIS INSTRUCTOR-PROVIDED FILE.

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

/**
 * 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.
 */
public class Main {
	/** Runs the overall program's console user interface. */
	public static void main(String[] args) throws FileNotFoundException {
		System.out.println("CSE 373 Stable Marriage simulator");
		System.out.println("=================================");
		System.out.println("This program reads a file of men and women's preferences");
		System.out.println("and tries to find a 'stable' grouping of couples.");
		System.out.println();

		// prompt for input file name
		System.out.print("Input file name? ");
		Scanner console = new Scanner(System.in);
		String filename = console.nextLine();
		Scanner input = new Scanner(new File(filename));
		
		// read data from input file
		MatchMaker maker = new MatchMaker();
		readInput(input, maker);

		// 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
		int round = 0;
		while (!maker.isStable() && (rounds == 0 || round < rounds)) {
			round++;
			System.out.println("Round " + round);
			maker.nextRound();
			System.out.println();
			
			System.out.println("Current matches:");
			maker.printMatches();
			System.out.println();
		}
		
		if (maker.isStable()) {
			System.out.println(round + " rounds performed and reached stable state.");
		} else {
			System.out.println(round + " rounds performed but did not reach stable state.");
		}
	}
	
	/** Reads the people input from the given file and puts it into the MatchMaker. */
	public static void readInput(Scanner input, MatchMaker maker) {
		while (input.hasNextLine()) {
			String line = input.nextLine().trim();
			if (line.length() == 0 || line.startsWith("#")) {
				// this is an empty line or a comment line in the file; ignore
				continue;
			} else {
				// read one person's info; break apart line by ; or , with optional spaces
				String[] tokens = line.split("[ ]*[:,][ ]*");
				if (tokens.length < 3) {
					System.out.println("invalid input line: \"" + line + "\"");
					continue;
				}
				String name = tokens[0].intern();
				String gender = tokens[1].toUpperCase().intern();
				String[] preferences = new String[tokens.length - 2];
				for (int i = 0; i < preferences.length; i++) {
					preferences[i] = tokens[i + 2].intern();
				}
				
				// add the person to the MatchMaker
				maker.addPerson(name, gender, preferences);
			}
		}
	}
}