import java.util.ArrayList;
import java.util.Map;
import java.util.TreeMap;

/**
 * Holds the tally of votes for an election
 * 
 * @author Scot Drysdale
 */
public class VoteTally {
	Map<String, Integer> tally;
	
	/**
	 * Construct a tally with no votes
	 */
	public VoteTally() {
		tally = new TreeMap<String, Integer>();
	}
	
	/**
	 * Record a vote for a candidate.  If candidate not found,
	 *   add that candidate with a 1 vote total.
	 * @param candidate the name of the candidate to receive a vote
	 */
	public void recordVote(String candidate) {
		Integer currentTally = tally.get(candidate);
		if(currentTally != null) {
			tally.put(candidate,  currentTally + 1);
		}
		else
			tally.put(candidate, 1);    // New candidate. Add with 1 vote
	}
	
	/**
	 * Finds the candidates with the fewest votes.
	 * @return a list of candidates with the fewest votes.
	 */
	public ArrayList<String> getLosers() {
		ArrayList<String> loserList = new ArrayList<String>();
		int minTally = Integer.MAX_VALUE;  // Bigger than any possible vote count
		
		for(String candidate : tally.keySet()) {
			int candidateTally = tally.get(candidate);
			if(candidateTally < minTally) {  // Found new loser?
				loserList.clear();             // Forget previous losers
				loserList.add(candidate);      // Remember new loser
				minTally = candidateTally;			
			}
			else if(candidateTally == minTally)
				loserList.add(candidate);      // Have another with the same low tally
		}
		return loserList;
	}
	
	/**
	 * Return the election results
	 */
	public String toString() {
		return "Candidate names with vote tallies: \n" + tally.toString();
	}
}