source: src/main/java/negotiator/boaframework/opponentmodel/NashFrequencyModel.java

package negotiator.boaframework.opponentmodel;

import java.util.List;
import java.util.Map;

import genius.core.Bid;
import genius.core.boaframework.NegotiationSession;
import genius.core.boaframework.OpponentModel;
import genius.core.issue.Issue;
import genius.core.issue.IssueDiscrete;
import genius.core.issue.IssueInteger;
import genius.core.issue.IssueReal;
import genius.core.issue.Value;
import genius.core.utility.AdditiveUtilitySpace;
import negotiator.boaframework.opponentmodel.nash.AIssueEvaluation;
import negotiator.boaframework.opponentmodel.nash.IssueEvaluationDiscrete;
import negotiator.boaframework.opponentmodel.nash.IssueEvaluationInteger;
import negotiator.boaframework.opponentmodel.nash.IssueEvaluationList;
import negotiator.boaframework.opponentmodel.nash.IssueEvaluationReal;
import negotiator.boaframework.opponentmodel.nash.Range;
import negotiator.boaframework.opponentmodel.tools.UtilitySpaceAdapter;

/**
 * This class holds the model of a negotiator, which will be constructed by it's
 * bids. The opponentmodel will be based on frequency/distribution analysis.
 * 
 * - The importance of a discrete issue and it's values will be calculated by
 * the difference in the number of times a certain value is chosen. - The
 * importance of a numerical issue will be calculated by the first offered
 * values and the range in which our own issue has a utility > 0. We will then
 * interpolate between the max utility value and the min utility value.
 *
 * Adapted by Mark Hendrikx to be compatible with the BOA framework.
 *
 * Tim Baarslag, Koen Hindriks, Mark Hendrikx, Alex Dirkzwager and Catholijn M.
 * Jonker. Decoupling Negotiating Agents to Explore the Space of Negotiation
 * Strategies
 * 
 * @author Roland van der Linden, Mark Hendrikx
 */
public class NashFrequencyModel extends OpponentModel {
        // **************************************
        // Fields
        // **************************************

        // The list of issueEvaluations which hold the analysis.
        private IssueEvaluationList issueEvaluationList;

        @Override
        public void init(NegotiationSession domainKnow, Map<String, Double> parameters) {
                negotiationSession = domainKnow;
                initModel();
        }

        /**
         * This initializes the negotiatormodel, creating an issueEvaluation for
         * each issue in the utilitySpace.
         */
        private void initModel() {
                List<Issue> issues = negotiationSession.getUtilitySpace().getDomain().getIssues();

                this.issueEvaluationList = new IssueEvaluationList(issues.size());

                // Create an empty issueEvaluation object for each issue in the domain.
                // This will later contain all information we can gather on the
                // negotiator.
                for (int index = 0; index < issues.size(); index++) {
                        Issue issue = issues.get(index);
                        AIssueEvaluation issueEvaluation = null;

                        if (issue instanceof IssueDiscrete)
                                issueEvaluation = new IssueEvaluationDiscrete((IssueDiscrete) issue);
                        else if (issue instanceof IssueInteger) {
                                // We use the range in which our utility is non-zero to estimate
                                // the distribution of the opponent.
                                IssueInteger issueI = (IssueInteger) issue;
                                Range ourNonZeroUtilityRange = new Range(issueI.getLowerBound(), issueI.getUpperBound());
                                issueEvaluation = new IssueEvaluationInteger((IssueInteger) issue, ourNonZeroUtilityRange);
                        } else if (issue instanceof IssueReal) {
                                // We use the range in which our utility is non-zero to estimate
                                // the distribution of the opponent.
                                IssueReal issueR = (IssueReal) issue;
                                Range ourNonZeroUtilityRange = new Range(issueR.getLowerBound(), issueR.getUpperBound());
                                issueEvaluation = new IssueEvaluationReal((IssueReal) issue, ourNonZeroUtilityRange);
                        } else
                                throw new UnsupportedOperationException("There is no implementation for that issueType.");

                        // Add the new issueEvaluation to the list.
                        this.issueEvaluationList.addIssueEvaluation(issueEvaluation);
                }
        }

        // **************************************
        // Update model
        // **************************************

        /**
         * This will receiveMessage the negotiatormodel based on a new bid that has
         * just been offered by the negotiator.
         * 
         * @param bid
         *            The bid that has just been offered.
         */
        public void updateModel(Bid bid, double time) {
                if (bid != null) {
                        // We receiveMessage each issueEvaluation with the value that has
                        // been offered in the bid.
                        List<Issue> issues = negotiationSession.getUtilitySpace().getDomain().getIssues();
                        for (Issue issue : issues) {
                                try {
                                        int issueID = issue.getNumber();
                                        Value offeredValue = bid.getValue(issueID);
                                        this.issueEvaluationList.updateIssueEvaluation(issueID, offeredValue);
                                } catch (Exception e) {
                                        e.printStackTrace();
                                }
                        }
                        // After all issueEvaluations have been updated, we can calculate
                        // the new
                        // estimated weights for the issues themselves.
                        this.issueEvaluationList.updateIssueWeightMap();
                }
        }

        // ****************************************
        // Utility
        // ****************************************

        /**
         * This method estimates the utility of the negotiator given that it has
         * just offered the given bid. The utility estimation is done by multiplying
         * the normalized issue weights with the normalized offered-value weight of
         * that issue.
         * 
         * Note that the utility of a bid will always be in between 0 - 1. Note that
         * this method does not take discount into account.
         * 
         * @param bid
         *            The bid that has just been offered by the negotiator that we
         *            are evaluating.
         * @return The estimated utility of the bid that has been offered by the
         *         negotiator we are evaluating.
         */
        public double getBidEvaluation(Bid bid) {
                double result = 0;
                if (issueEvaluationList.isReady()) {
                        List<Issue> issues = negotiationSession.getUtilitySpace().getDomain().getIssues();

                        double totalEstimatedUtility = 0;
                        for (Issue issue : issues) {
                                try {
                                        int issueID = issue.getNumber();

                                        // Get the estimated normalized weight of the issue, which
                                        // indicates how important the issue is.
                                        double issueWeight = this.issueEvaluationList.getNormalizedIssueWeight(issueID);

                                        // Get the estimated normalized weight of the value of the
                                        // issue, which corresponds to the value that has
                                        // been offered in the bid.
                                        Value offeredValue = bid.getValue(issueID);
                                        AIssueEvaluation issueEvaluation = this.issueEvaluationList.getIssueEvaluation(issueID);
                                        double offeredValueWeight = issueEvaluation.getNormalizedValueWeight(offeredValue);

                                        // Since all issueWeights combined should add up to 1, and
                                        // the maximum value of the valueWeight is 1,
                                        // the estimated utility should be exactly 1 if all offered
                                        // valueWeights are 1. So to calculate the partial estimated
                                        // utility for this specific issue-value combination, we
                                        // need to multiply the weights.
                                        totalEstimatedUtility += (issueWeight * offeredValueWeight);
                                } catch (Exception e) {
                                        e.printStackTrace();
                                }
                        }

                        // Make sure to remove roundoff errors from the utility.
                        result = Math.min(1, Math.max(0, totalEstimatedUtility));
                }
                return result;
        }

        // ****************************************
        // toString
        // ****************************************

        /**
         * This returns a string representation of the negotiatormodel.
         */
        public String toString() {
                return this.issueEvaluationList.toString();
        }

        public double getWeight(Issue issue) {
                // Get the estimated normalized weight of the issue, which indicates how
                // important the issue is.
                return this.issueEvaluationList.getNormalizedIssueWeight(issue.getNumber());
        }

        @Override
        public String getName() {
                return "NASH Frequency Model";
        }

        public AdditiveUtilitySpace getOpponentUtilitySpace() {
                if (issueEvaluationList.isReady()) {
                        return new UtilitySpaceAdapter(this, negotiationSession.getUtilitySpace().getDomain());
                } else {
                        System.out.println("Returned own utilityspace to avoid an error (normal on first turn).");
                        return (AdditiveUtilitySpace) negotiationSession.getUtilitySpace();
                }
        }
}