source: events/src/main/java/geniusweb/actions/Votes.java@ 26

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 + "]";
        }
}