source: src/main/java/agents/anac/y2010/AgentSmith/SmithBidStrategy.java@ 84

package agents.anac.y2010.AgentSmith;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
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.Offer;
import genius.core.issue.Issue;
import genius.core.issue.Value;
import genius.core.utility.AdditiveUtilitySpace;

/**
 * The strategy that is used in our agent. It samples the bid space, takes the
 * bids that are near Pareto and returns them as next actions.
 * 
 * NOTE There are two bugs in this strategy: 1. The agent incorrectly assumes
 * that there are only 2 minutes 2. The agent checks if it gave "enough" utility
 * to the opponent instead of itself
 */
public class SmithBidStrategy extends ABidStrategy {
        private int fIndex = 0;

        static private double sUtilyMargin = 0.7;
        static private double sTimeMargin = 110; // in seconds

        static private double UTILITY_THRESHOLD = 0.7;
        private final boolean TEST_EQUIVALENCE = false;

        /**
         * Constructor
         * 
         * @param pHist
         *            The bidhistory
         * @param utilitySpace
         *            Utilityspace
         * @param pPreferenceProfile
         *            Preference profile
         * @param pId
         *            Our id
         */
        public SmithBidStrategy(BidHistory pHist,
                        AdditiveUtilitySpace utilitySpace,
                        PreferenceProfileManager pPreferenceProfile, AgentID pId) {
                super(pHist, utilitySpace, pPreferenceProfile, pId);
                if (TEST_EQUIVALENCE) {
                        sTimeMargin = 170;
                }
        }

        /**
         * Generate in new action
         */
        public Action getNextAction(double time) {
                double normalTime = time * 180;
                Action lAction = null;
                // Time in seconds.
                try {
                        // Check if the session (2 min) is almost finished
                        if (normalTime >= sTimeMargin) {
                                // If the session is almost finished check if the utility is
                                // "high enough"
                                Bid lastBid = fBidHistory.getOpponentLastBid();

                                boolean result = false;
                                if (TEST_EQUIVALENCE) {
                                        result = fPreferenceProfile.getMyUtility(lastBid) >= sUtilyMargin;
                                } else {
                                        result = fPreferenceProfile.getOpponentUtility(lastBid) >= sUtilyMargin;
                                }
                                if (result) {
                                        lAction = new Accept(fAgentID, lastBid);
                                } else {
                                        lAction = new Offer(fAgentID, getBestOpponentOffer());
                                }
                        } else {
                                lAction = new Offer(fAgentID, getMostOptimalBid());
                        }
                } catch (Exception e) {
                        lAction = null;
                }
                return lAction;
        }

        /**
         * Calculate the most optimal bid
         * 
         * @return the most optimal bid
         * @throws Exception
         */
        public Bid getMostOptimalBid() {
                ArrayList<Bid> lBids = getSampledBidList();

                // Log.logger.info("Size of bid space: " + lBids.size());
                BidComparator lComparator = new BidComparator(this.fPreferenceProfile);

                // sort the bids in order of highest utility
                Collections.sort(lBids, lComparator);

                Bid lBid = lBids.get(fIndex);
                if (fIndex < lBids.size() - 1)
                        fIndex++;

                return lBid;
        }

        /**
         * Return the best offer made by your opponent. When time is running out
         * this method is called to find the best bid available.
         * 
         * @return
         * @throws Exception
         */
        public Bid getBestOpponentOffer() {
                double util = 0;
                Bid bestBid = null;

                try {
                        // check for the highest bid offered by the opponent
                        for (int i = 0; i < fBidHistory.getOpponentBidCount(); i++) {
                                if (fUtilitySpace.getUtility(fBidHistory.getOpponentBid(i)) > util) {
                                        util = fUtilitySpace.getUtility(fBidHistory
                                                        .getOpponentBid(i));
                                        bestBid = fBidHistory.getOpponentBid(i);
                                }
                        }
                } catch (Exception e) {
                        bestBid = null;
                }

                return bestBid;
        }

        /**
         * returns an ArrayList with possible bids This function constructs all
         * samples of the entire bidspace.
         */
        private ArrayList<Bid> getSampledBidList() {
                ArrayList<Bid> lBids = new ArrayList<Bid>();
                List<Issue> lIssues = this.fPreferenceProfile.getIssues();
                HashMap<Integer, Bounds> lBounds = Bounds.getIssueBounds(lIssues);

                // first createFrom a new list
                HashMap<Integer, Value> lBidValues = new HashMap<Integer, Value>();
                for (Issue lIssue : lIssues) {
                        Bounds b = lBounds.get(lIssue.getNumber());
                        Value v = Bounds.getIssueValue(lIssue, b.getLower());
                        lBidValues.put(lIssue.getNumber(), v);
                }
                try {
                        lBids.add(new Bid(this.fPreferenceProfile.getDomain(), lBidValues));
                } catch (Exception e) {
                }

                // for each item permutate with issue values, like binary
                // 0 0 0
                // 0 0 1
                // 0 1 0
                // 0 1 1
                // etc.
                for (Issue lIssue : lIssues) {
                        ArrayList<Bid> lTempBids = new ArrayList<Bid>();
                        Bounds b = lBounds.get(lIssue.getNumber());
                        for (Bid lTBid : lBids) {
                                for (double i = b.getLower(); i < b.getUpper(); i += b
                                                .getStepSize()) {
                                        HashMap<Integer, Value> lNewBidValues = getBidValues(lTBid);
                                        lNewBidValues.put(lIssue.getNumber(),
                                                        Bounds.getIssueValue(lIssue, i));

                                        try {
                                                Bid iBid = new Bid(this.fPreferenceProfile.getDomain(),
                                                                lNewBidValues);
                                                lTempBids.add(iBid);

                                        } catch (Exception e) {

                                        }
                                }
                        }
                        lBids = lTempBids;
                }

                ArrayList<Bid> lToDestroy = new ArrayList<Bid>();
                for (Bid lBid : lBids) {

                        if (this.fPreferenceProfile.getMyUtility(lBid) < UTILITY_THRESHOLD) {
                                lToDestroy.add(lBid);
                        }
                }
                for (Bid lBid : lToDestroy) {
                        lBids.remove(lBid);
                }

                return lBids;
        }

        /**
         * Get the values of a bid
         * 
         * @param pBid
         * @return
         */
        private HashMap<Integer, Value> getBidValues(Bid pBid) {
                HashMap<Integer, Value> lNewBidValues = new HashMap<Integer, Value>();
                for (Issue lIssue : this.fPreferenceProfile.getIssues()) {
                        try {
                                lNewBidValues.put(lIssue.getNumber(),
                                                pBid.getValue(lIssue.getNumber()));
                        } catch (Exception e) {

                        }
                }
                return lNewBidValues;
        }

}