source: src/main/java/agents/anac/y2010/Southampton/similarity/SimilarityAgent.java@ 127

package agents.anac.y2010.Southampton.similarity;

import java.util.ArrayList;

import agents.anac.y2010.Southampton.SouthamptonAgent;
import agents.anac.y2010.Southampton.utils.OpponentModel;
import agents.anac.y2010.Southampton.utils.Pair;
import genius.core.Bid;
import genius.core.utility.AdditiveUtilitySpace;

public abstract class SimilarityAgent extends SouthamptonAgent {

        /**
         * The best bids (in terms of our utility) that we have seen from the
         * opponent.
         */
        protected ArrayList<Pair<Double, Double>> bestOpponentBidUtilityHistory;
        /**
         * The best bid (in terms of our utility) that we have seen from the
         * opponent.
         */
        private Bid bestOpponentBid;

        /**
         * The utility (to us) of the best bid (in terms of our utility) that we
         * have seen from the opponent.
         */
        private double bestOpponentUtility;

        /**
         * The utility (to us) of the first bid made by the opponent.
         */
        protected double utility0 = 0;

        /**
         * The expected utility (to us) of the final bid made by the opponent.
         */
        protected final double utility1 = 0.95;

        public SimilarityAgent() {
                super();
                bestOpponentBidUtilityHistory = new ArrayList<Pair<Double, Double>>();
                // CONCESSIONFACTOR = 0.01;
        }

        public void init() {
                super.init();
                prepareOpponentModel();
        }

        @Override
        public String getVersion() {
                return "1.0";
        }

        protected Bid proposeInitialBid() {
                Bid bid = null;

                try {
                        bid = bidSpace.getMaxUtilityBid();
                } catch (Exception e) {
                        e.printStackTrace();
                }
                return bid;
        }

        protected Bid proposeNextBid(Bid opponentBid) {
                try {
                        performUpdating(opponentBid);
                } catch (Exception e) {
                        e.printStackTrace();
                }

                double myUtility = 0, opponentUtility = 0, targetUtility;
                // Both parties have made an initial bid. Compute associated utilities
                // from my point of view.
                try {
                        myUtility = utilitySpace.getUtility(myLastBid);
                        opponentUtility = utilitySpace.getUtility(opponentBid);
                        if (opponentPreviousBid == null)
                                utility0 = opponentUtility;
                } catch (Exception e) {
                        e.printStackTrace();
                }
                targetUtility = getTargetUtility(myUtility, opponentUtility);
                Bid nextBid = getTradeOffExhaustive(targetUtility, opponentBid, 1000);
                return nextBid;
        }

        protected abstract double getTargetUtility(double myUtility,
                        double opponentUtility);

        /*
         * (non-Javadoc)
         * 
         * @see agents.southampton.SouthamptonAgent#getRandomBidInRange(double,
         * double)
         */
        @Override
        protected Bid getRandomBidInRange(double lowerBound, double upperBound)
                        throws Exception {
                throw new Exception(
                                "Method 'getRandomBidInRange' is not implemented in this agent.");
        }

        private Bid getTradeOffExhaustive(double ourUtility, Bid opponentBid,
                        int count) {
                // Project a point onto the bidspace...
                bestOpponentBid = getBestBid(opponentBid);

                if (bestOpponentUtility * acceptMultiplier >= ourUtility) {
                        return bestOpponentBid;
                }

                ArrayList<Bid> bids = bidSpace.Project(
                                bidSpace.getPoint(bestOpponentBid), ourUtility, count,
                                (AdditiveUtilitySpace) this.utilitySpace, this.opponentModel);
                if (bids.size() == 0) {
                        return getTradeOffExhaustive(ourUtility, opponentBid, count + 10000);
                }
                double maxOpponentUtility = 0;
                Bid bestBid = null;

                for (Bid bid : bids) {
                        try {
                                double opponentUtility = opponentModel
                                                .getNormalizedUtility(bid);
                                if (opponentUtility > maxOpponentUtility) {
                                        maxOpponentUtility = opponentUtility;
                                        bestBid = bid;
                                }
                        } catch (Exception e) {
                                e.printStackTrace();
                        }
                }

                return bestBid;
        }

        private Bid getBestBid(Bid opponentBid) {
                double utility;
                try {
                        utility = utilitySpace.getUtility(opponentBid);
                        if (utility >= bestOpponentUtility) {
                                bestOpponentUtility = utility;
                                bestOpponentBid = opponentBid;
                        }
                        storeDataPoint(bestOpponentUtility);
                } catch (Exception e) {
                        e.printStackTrace();
                }
                return bestOpponentBid;
        }

        private void storeDataPoint(double utility) {
                double time = timeline.getTime();
                // bestOpponentBidUtilityHistory.add(new Pair<Double,
                // Double>(-Math.log(1 - ((utility - utility0) / (utility1 -
                // utility0))), time));
                bestOpponentBidUtilityHistory.add(new Pair<Double, Double>(utility,
                                time));
        }

        private void performUpdating(Bid opponentBid) throws Exception {
                double currentTime = timeline.getTime() * timeline.getTotalTime()
                                * 1000;
                double totalTime = timeline.getTotalTime() * 1000;
                opponentModel.updateBeliefs(opponentBid, Math.round(currentTime),
                                totalTime);
        }

        private void prepareOpponentModel() {
                opponentModel = new OpponentModel((AdditiveUtilitySpace) utilitySpace);
        }
}