package geniusweb.actions;

import java.util.Collections;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Optional;
import java.util.Set;
import java.util.stream.Collectors;

import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;

import geniusweb.issuevalue.Bid;

/**
 * Indicates that a party conditionally agrees with any of the {@link Vote}s
 * provided.
 */
public class Votes extends AbstractAction {
	private final Set<Vote> votes;

	/**
	 * 
	 * @param id    party id
	 * @param votes the {@link Vote}s that the party can agree on, if the
	 *              condition of the Vote holds. Every {@link Vote#getActor()}
	 *              should equal the id
	 */
	@JsonCreator
	public Votes(@JsonProperty("actor") PartyId id,
			@JsonProperty("votes") Set<Vote> votes) {
		super(id);
		this.votes = votes;
		if (votes == null)
			throw new NullPointerException("votes must be not null");
		for (Vote vote : votes) {
			if (!vote.getActor().equals(id)) {
				throw new IllegalArgumentException("All votes must come from "
						+ id + " but found " + vote);
			}
		}
		// check for duplicate Vote's, possibly with different powers
		Map<Bid, Long> counts = votes.stream().map(vote -> vote.getBid())
				.collect(Collectors.groupingBy(bid -> bid,
						Collectors.counting()));
		Optional<Entry<Bid, Long>> nonunique = counts.entrySet().stream()
				.filter(entry -> entry.getValue() > 1).findAny();
		if (nonunique.isPresent())
			throw new IllegalArgumentException(
					"Votes contains multiple Vote's for "
							+ nonunique.get().getKey());

	}

	/**
	 * Test if Votes extends other votes. Extending means that for each vote on
	 * bid B with power P in othervotes, this contains also a vote for bid B
	 * with power at most P.
	 * 
	 * @param otherVotes the {@link Votes}, usually from a previous round, that
	 *                   this should extend.
	 * @return true iff this extends the otherVotes.
	 */
	public boolean isExtending(Votes otherVotes) {
		if (!otherVotes.getActor().equals(getActor()))
			return false;
		for (Vote vote : otherVotes.getVotes()) {
			Vote myvote = getVote(vote.getBid());
			if (myvote == null || myvote.getMinPower() > vote.getMinPower()
					|| myvote.getMaxPower() < vote.getMaxPower())
				return false;
		}
		return true;
	}

	/**
	 * 
	 * @param bid the bid that we may have a vote for
	 * @return myvote for bid, or null if no vote for that bid;
	 */
	public Vote getVote(Bid bid) {
		for (Vote vote : votes) {
			if (vote.getBid().equals(bid))
				return vote;
		}
		return null;
	}

	public Set<Vote> getVotes() {
		return Collections.unmodifiableSet(votes);
	}

	@Override
	public int hashCode() {
		final int prime = 31;
		int result = super.hashCode();
		result = prime * result + ((votes == null) ? 0 : votes.hashCode());
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (!super.equals(obj))
			return false;
		if (getClass() != obj.getClass())
			return false;
		Votes other = (Votes) obj;
		if (votes == null) {
			if (other.votes != null)
				return false;
		} else if (!votes.equals(other.votes))
			return false;
		return true;
	}

	@Override
	public String toString() {
		return "Votes[" + getActor() + "," + votes + "]";
	}
}