source: src/main/java/agents/ai2014/group8/Group8.java@ 127

package agents.ai2014.group8;

import java.util.ArrayList;
import java.util.List;

import genius.core.AgentID;
import genius.core.Bid;
import genius.core.actions.Accept;
import genius.core.actions.Action;
import genius.core.actions.Inform;
import genius.core.actions.Offer;
import genius.core.issue.Issue;
import genius.core.parties.AbstractNegotiationParty;
import genius.core.parties.NegotiationInfo;

/**
 * This is your negotiation party.
 */
public class Group8 extends AbstractNegotiationParty {

        // utility value above which bids will be accepted
        private double acceptanceValue;

        // number of rounds available for negotiation
        private double totalRounds;

        // number of rounds of negotiation completed
        private int roundCounter;

        private static final double INITIALACCEPTVALUE = 0.5;

        // most recent bid
        private Bid mostRecentBid;

        // most recent bidder
        private AgentID mostRecentBidder;

        // list of opponents modeled by opponentModel class
        private List<OpponentModel> opponents;

        @Override
        public void init(NegotiationInfo info) {
                super.init(info);

                // get total number of rounds available from the environment
                this.totalRounds = timeline.getTotalTime() - 1;

                this.roundCounter = 0;

        }

        /**
         * Each round this method gets called and ask you to accept or offer. The
         * first party in the first round is a bit different, it can only propose an
         * offer.
         *
         * @param validActions
         *            Either a list containing both accept and offer or only offer.
         * @return The chosen action.
         */
        @Override
        public Action chooseAction(List<Class<? extends Action>> validActions) {
                this.roundCounter++;

                this.acceptanceValue = 0.99 + 1 - Math.pow(Math.pow(1.9, 1 / this.totalRounds),
                                Math.pow(INITIALACCEPTVALUE, (this.totalRounds) / this.roundCounter) * (this.roundCounter - 1));

                // first bid - offer a bid with high utility value for self
                if (!validActions.contains(Accept.class)) {
                        Bid firstBid = this.generateHigherUtilityBid(this.acceptanceValue).get(0);

                        return new Offer(getPartyId(), firstBid);
                }
                // choosing action after a bid has been made
                else {
                        // evaluate the utility of most recent bid
                        double utilityOfMostRecentBid;

                        try {
                                utilityOfMostRecentBid = this.utilitySpace.getUtility(this.mostRecentBid);
                        } catch (Exception e) {
                                utilityOfMostRecentBid = 0;
                                e.printStackTrace();
                        }

                        // accept offer if utility is higher than our acceptance value
                        if (utilityOfMostRecentBid >= this.acceptanceValue) {
                                return new Accept(getPartyId(), mostRecentBid);
                        }
                        // make counter offer
                        else {
                                // generate some high utility bids
                                List<Bid> possibleBids = generateHigherUtilityBid(this.acceptanceValue);

                                // when too few rounds have passed, offer a random high utility
                                // bid
                                if (this.roundCounter < 5) {
                                        return new Offer(getPartyId(), possibleBids.get(0));
                                }
                                // among high utility bids choose one that has best utility for
                                // next agent
                                else {
                                        // find bid with highest utility for next agent
                                        double maxUtilityForOpponent = 0.0;
                                        Bid bestBidForNextAgent = null;

                                        OpponentModel nextAgent = getNextAgentModel();

                                        for (Bid bid : possibleBids) {
                                                double bidUtility = nextAgent.EvaluateBidUtility(bid);

                                                if (bidUtility > maxUtilityForOpponent) {
                                                        bestBidForNextAgent = bid;
                                                        maxUtilityForOpponent = bidUtility;
                                                }
                                        }

                                        return new Offer(getPartyId(), bestBidForNextAgent);
                                }
                        }
                }
        }

        /**
         * find next agent among list of opponents
         * 
         * @return model of next agent
         */
        private OpponentModel getNextAgentModel() {
                OpponentModel nextAgent = null;

                for (OpponentModel opponent : this.opponents) {
                        if (opponent.agent.equals(this.mostRecentBidder)) {
                                int indexOfPreviousBidder = this.opponents.indexOf(mostRecentBidder);

                                int indexOfNextAgent = (indexOfPreviousBidder + 1) % this.opponents.size();

                                nextAgent = this.opponents.get(indexOfNextAgent);
                                break;
                        }
                }
                return nextAgent;
        }

        /**
         * All offers proposed by the other parties will be received as a message.
         * You can use this information to your advantage, for example to predict
         * their utility.
         *
         * @param sender
         *            The party that did the action.
         * @param action
         *            The action that party did.
         */
        @Override
        public void receiveMessage(AgentID sender, Action action) {
                // handle first message from framework to initialize list of opponents
                if (sender == null) {
                        super.receiveMessage(sender, action);

                        // get number of agents in the negotiation
                        Inform agentsInformation = (Inform) action;
                        int numberOfAgents = (Integer) agentsInformation.getValue();

                        // initialize list of other parties
                        if (numberOfAgents > 1) {
                                this.opponents = new ArrayList<OpponentModel>();
                        }
                        return;
                }

                this.mostRecentBidder = sender;

                List<Issue> issues = getUtilitySpace().getDomain().getIssues();
                // add sender agent to list of other parties if not present
                if (this.opponents.contains(new OpponentModel(sender, issues)) == false) {
                        OpponentModel newOpponent = new OpponentModel(sender, issues);
                        this.opponents.add(newOpponent);
                }

                // store sender agent bid in its model among list of opponents
                if ((action instanceof Offer)) {
                        mostRecentBid = ((Offer) action).getBid();

                        OpponentModel senderModel = null;

                        for (OpponentModel opponent : this.opponents) {
                                if (opponent.agent == sender) {
                                        senderModel = opponent;
                                        break;
                                }
                        }

                        if (senderModel != null) {
                                try {
                                        senderModel.AddBid(mostRecentBid);
                                } catch (Exception e) {
                                        e.printStackTrace();
                                        return;
                                }
                        }
                }
        }

        /**
         * generates random bids which have higher utility than the parameter
         *
         * @param utilityValue
         *            lower bound of utility value for randomly generated bids
         */
        private List<Bid> generateHigherUtilityBid(double utilityValue) {
                Bid randomBid;
                List<Bid> randomBidsList = new ArrayList<Bid>();

                double util;
                do {
                        randomBid = generateRandomBid();

                        try {
                                util = utilitySpace.getUtility(randomBid);
                        } catch (Exception e) {
                                util = 0.0;
                        }

                        if (util > utilityValue && util < (utilityValue + 0.05)) {
                                randomBidsList.add(randomBid);
                        }
                } while (randomBidsList.size() < 10);

                return randomBidsList;
        }

        protected AgentID partyId = new AgentID("Group 8");

        @Override
        public String getDescription() {
                return "ai2014 group8";
        }

}