package webcrawler;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import Jama.Matrix;
import java.util.Set;

public class Ranking {
	private final double DAMPING_FACTOR = 0.85;
        private Map<String, String[]> mapInbound = new HashMap();
        private Map<String, String[]> mapOutbound = new HashMap();
	private List params = new ArrayList();

        DB db = new DB("jdbc:mysql://localhost:3306/webcrawlerdb","root",""); // set server address, username and password

        public void start() {
            InboundLinks();
            OutboundLinks();
            Set urls = db.getLinks();

            Iterator it = urls.iterator();
            double sum = 0;
            while(it.hasNext()){
                Object url = it.next();
                db.insertRank(url.toString(), rank(url.toString()));
                sum += (rank(url.toString()));
            }
            System.out.println("PageRank finnished");
        }

	/*public static void main(String[] args) {
            Ranking ranking = new Ranking();
	}*/

        private void InboundLinks() {
            mapInbound = db.generateInboundLinks();

            /*for (Map.Entry entry : mapInbound.entrySet()) {
                String[] inboundsArray = (String[]) entry.getValue();
                System.out.println(entry.getKey() + "|||" + Arrays.toString(inboundsArray));
            }*/
        }

        private void OutboundLinks() {
            mapOutbound = db.generateOutboundLinks();
        }

	public double rank(String pageId) {
            generateParamList(pageId);
            Matrix a = new Matrix(generateMatrix());
            double[][] arrB = new double[params.size()][1];
            for (int i = 0; i < params.size(); i++) {
                arrB[i][0] = 1 - DAMPING_FACTOR;
            }
            Matrix b = new Matrix(arrB);
            // Solve the equation and get the page ranks
            Matrix x = a.solve(b);
            int ind = 0;
            int cnt = 0;
            for (Iterator it = params.iterator(); it.hasNext();) {
                String curPage = (String) it.next();
                if (curPage.equals(pageId))
                    ind = cnt;
                cnt++;
            }
            return x.getArray()[ind][0];
	}

	private double[][] generateMatrix() {
            double[][] arr = new double[params.size()][params.size()];
            for (int i = 0; i < params.size(); i++) {
                for (int j = 0; j < params.size(); j++) {
                    arr[i][j] = getMultiFactor((String) params.get(i),
                    (String) params.get(j));
                }
            }
            return arr;
	}


                private double getMultiFactor(String sourceId, String linkId) {
            if (sourceId.equals(linkId))
                return 1;
            else {
                String[] inc = getInboundLinks(sourceId);
                for (int i = 0; i < inc.length; i++) {
                    if (inc[i].equals(linkId)) {
                        return -1 * (DAMPING_FACTOR / getOutboundLinks(linkId).length);
                    }
                }
            }
            return 0;
	}

	private void generateParamList(String pageId) {
            // Add the starting page.
            if (!params.contains(pageId))
                params.add(pageId);
            // Get list of the inbound pages
            String[] inc = getInboundLinks(pageId);
            // Add the inbound links to the params list and do same for inbound
            // links
            for (int i = 0; i < inc.length; i++) {
                if (!params.contains(inc[i]))
                    generateParamList(inc[i]);
            }
	}

	private String[] getInboundLinks(String pageId) {
            return (String[]) mapInbound.get(pageId);
	}

	private String[] getOutboundLinks(String pageId) {
            return (String[]) mapOutbound.get(pageId);
	}
}