source: src/main/java/parties/in4010/q12015/group7/IssueEstimator.java@ 148

package parties.in4010.q12015.group7;

import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import genius.core.Bid;
import genius.core.BidHistory;
import genius.core.issue.Issue;
import genius.core.issue.Value;

/**
 * Opponent Modeler which estimates issue weights and values according to the
 * bids that are added
 * 
 * @author svanbekhoven
 */
public class IssueEstimator {
        /**
         * Weights of all issues
         */
        private HashMap<Integer, Double> issueWeights;

        /**
         * Weights of all issue values
         */
        private HashMap<Integer, HashMap<Value, Integer>> issueValueWeights;

        /**
         * Sensitivity parameter
         */
        private double n;

        /**
         * Constructor
         * 
         * @param n
         *            sensitivity parameter
         */
        public IssueEstimator(double n) {
                this.n = n;
                this.issueWeights = new HashMap<Integer, Double>();
                this.issueValueWeights = new HashMap<Integer, HashMap<Value, Integer>>();
        }

        /**
         * Add a bid to the issue estimator, automatically recalculating the issue
         * weights and issue value weights
         * 
         * @param bid
         *            bid you want to add to the estimator
         * @param bidHistory
         *            bidHistory belonging to the opponent you received the bid from
         *            (excluding(!) the bid in the first parameter)
         */
        public void addBid(Bid bid, BidHistory bidHistory) {
                List<Issue> issues = bid.getIssues();

                for (Issue issue : issues) {
                        Integer issueNumber = issue.getNumber();
                        Value issueValue = null;

                        try {
                                issueValue = bid.getValue(issueNumber);
                        } catch (Exception e) {
                                e.printStackTrace();
                        }

                        this.updateIssueValueWeights(bid, issues, issueNumber, issueValue);
                        this.updateIssueWeights(bid, bidHistory, issues, issueNumber,
                                        issueValue);
                }

                this.normalizeWeights();
        }

        /**
         * Update the issueValueWeights according to a new bid
         * 
         * @param bid
         * @param issues
         * @param issueNumber
         * @param issueValue
         */
        private void updateIssueValueWeights(Bid bid, List<Issue> issues,
                        Integer issueNumber, Value issueValue) {
                if (!issueValueWeights.containsKey(issueNumber)) {
                        issueValueWeights.put(issueNumber, new HashMap<Value, Integer>());
                }

                if (!issueValueWeights.get(issueNumber).containsKey(issueValue)) {
                        issueValueWeights.get(issueNumber).put(issueValue, 0);
                }

                issueValueWeights.get(issueNumber).put(issueValue,
                                issueValueWeights.get(issueNumber).get(issueValue) + 1);
        }

        /**
         * Update the issueWeights according to a new bid
         * 
         * @param bid
         * @param bidHistory
         * @param issues
         * @param issueNumber
         * @param issueValue
         */
        private void updateIssueWeights(Bid bid, BidHistory bidHistory,
                        List<Issue> issues, Integer issueNumber, Value issueValue) {
                if (!issueWeights.containsKey(issueNumber)) {
                        issueWeights.put(issueNumber, (double) (1.0 / issues.size()));
                }

                Bid lastBid = null;
                if (bidHistory.size() != 0) {
                        try {
                                lastBid = bidHistory.getLastBid();
                                if (lastBid.getValue(issueNumber).equals(issueValue)) {
                                        issueWeights.put(issueNumber, issueWeights.get(issueNumber)
                                                        + n);
                                }
                        } catch (Exception e) {
                                e.printStackTrace();
                        }
                }
        }

        /**
         * Normalizes the issueWeights
         */
        private void normalizeWeights() {
                Double sum = 0.0;
                for (Double weight : this.issueWeights.values()) {
                        sum += weight;
                }
                for (Map.Entry<Integer, Double> entry : issueWeights.entrySet()) {
                        issueWeights.put(entry.getKey(), entry.getValue() / sum);
                }
        }

        /**
         * Find the maximum weight of all values
         * 
         * @param valueWeights
         * @return maximum value
         */
        private double maxHashMap(HashMap<Value, Integer> valueWeights) {
                return Collections.max(valueWeights.values());
        }

        /**
         * Returns the issueWeights
         * 
         * @return
         */
        private HashMap<Integer, Double> getIssueWeights() {
                return this.issueWeights;
        }

        /**
         * Returns the issueValueWeights
         * 
         * @return
         */
        private HashMap<Integer, HashMap<Value, Double>> getValueWeights() {
                HashMap<Integer, HashMap<Value, Double>> returnValueWeights = new HashMap<Integer, HashMap<Value, Double>>();
                for (Map.Entry<Integer, HashMap<Value, Integer>> entry : issueValueWeights
                                .entrySet()) {
                        double max = maxHashMap(entry.getValue());
                        returnValueWeights
                                        .put(entry.getKey(), new HashMap<Value, Double>());
                        for (Map.Entry<Value, Integer> entryValue : entry.getValue()
                                        .entrySet()) {
                                returnValueWeights.get(entry.getKey()).put(entryValue.getKey(),
                                                entryValue.getValue() / max);
                        }
                }
                return returnValueWeights;
        }

        /**
         * Returns the utility of the bid for this issueEstimator
         * 
         * @param bid
         * @return
         */
        public double getUtility(Bid bid) {
                double sum = 0;
                double issueWeight = 0;
                List<Issue> issues = bid.getIssues();
                for (Issue i : issues) {
                        issueWeight = 0;
                        try {
                                if (this.getValueWeights().get(i.getNumber())
                                                .containsKey(bid.getValue(i.getNumber()))) {
                                        issueWeight = (double) this.getValueWeights()
                                                        .get(i.getNumber())
                                                        .get(bid.getValue(i.getNumber()));
                                }
                        } catch (Exception e) {
                                e.printStackTrace();
                        }
                        sum += ((double) this.getIssueWeights().get(i.getNumber()))
                                        * issueWeight;
                }

                return sum;
        }
}