package de.intevation.flys.artifacts.model.minfo;

import gnu.trove.TDoubleArrayList;

import java.util.Date;
import java.util.LinkedList;
import java.util.List;

import org.apache.log4j.Logger;

import de.intevation.flys.artifacts.FLYSArtifact;
import de.intevation.flys.artifacts.access.BedDifferencesAccess;
import de.intevation.flys.artifacts.model.Calculation;
import de.intevation.flys.artifacts.model.CalculationResult;


public class BedDiffCalculation
extends Calculation
{

    private static final Logger logger = Logger
        .getLogger(BedDiffCalculation.class);

    protected String river;
    protected String yearEpoch;
    protected FLYSArtifact[][] artifacts;

    public BedDiffCalculation() {
    }

    public CalculationResult calculate(BedDifferencesAccess access) {
        logger.info("BedDiffCalculation.calculate");

        String river = access.getRiver();
        String yearEpoch = access.getYearEpoch();
        FLYSArtifact[][] artifacts = access.getDifferenceArtifacts();

        logger.debug("got artifacts: " + artifacts.length + "; " + artifacts[0].length);
        if (river == null) {
            // TODO: i18n
            addProblem("minfo.missing.river");
        }

        if (yearEpoch == null) {
            addProblem("minfo.missing.year_epoch");
        }

        if (artifacts == null) {
            addProblem("minfo.missing.differences");
        }

        if (!hasProblems()) {
            this.river = river;
            this.yearEpoch = yearEpoch;
            this.artifacts = artifacts;
            return internalCalculate();
        }

        return new CalculationResult();
    }

    private CalculationResult internalCalculate() {

        if (yearEpoch.equals("year")) {
            List<BedDiffYearResult> results =
                new LinkedList<BedDiffYearResult>();

            for (int i = 0; i < artifacts.length; i++) {
                BedHeight[] pair =
                    getHeightPair(artifacts[i][0], artifacts[i][1], "single");
                BedDiffYearResult res = calculateYearDifference(pair);
                results.add(res);
            }
            return new CalculationResult(
                results.toArray(new BedDiffYearResult[results.size()]), this);
        }
        if (yearEpoch.equals("epoch")) {
            List<BedDiffEpochResult> results =
                new LinkedList<BedDiffEpochResult>();
            for (int i = 0; i < artifacts.length; i++) {
                BedHeight[] pair =
                    getHeightPair(artifacts[i][0], artifacts[i][1], "epoch");
                BedDiffEpochResult res = calculateEpochDifference(pair);
                results.add(res);
            }
            return new CalculationResult(
                results.toArray(new BedDiffEpochResult[results.size()]), this);
        }

       return new CalculationResult();
    }

    private BedHeight[] getHeightPair(
        FLYSArtifact art1,
        FLYSArtifact art2,
        String type
    ) {
        int id1 = BedDifferencesAccess.getHeightId(art1);
        int id2 = BedDifferencesAccess.getHeightId(art2);

        BedHeight[] heights = new BedHeight[2];
        heights[0] = BedHeightFactory.getHeight(type, id1, 0);
        heights[1] = BedHeightFactory.getHeight(type, id2, 0);
        return heights;
    }

    private BedDiffEpochResult calculateEpochDifference(BedHeight[] pair) {

        TDoubleArrayList stations = pair[0].getStations();
        TDoubleArrayList diffRes = new TDoubleArrayList();
        TDoubleArrayList kms = new TDoubleArrayList();
        TDoubleArrayList heights1 = new TDoubleArrayList();
        TDoubleArrayList heights2 = new TDoubleArrayList();

        for (int i = 0; i < stations.size(); i++) {
            if (!Double.isNaN(pair[0].getHeight(stations.get(i))) &&
                !Double.isNaN(pair[1].getHeight(stations.get(i)))) {
                double hDiff =
                    pair[0].getHeight(stations.get(i)) -
                    pair[1].getHeight(stations.get(i));
                diffRes.add(hDiff);
                kms.add(stations.get(i));
                heights1.add(pair[0].getHeight(stations.get(i)));
                heights2.add(pair[1].getHeight(stations.get(i)));
            }
        }
        Date start = ((BedHeightEpoch)pair[0]).getStart();
        Date end = ((BedHeightEpoch)pair[1]).getEnd();
        return new BedDiffEpochResult(kms, diffRes, heights1, heights2, start, end);
    }

    private BedDiffYearResult calculateYearDifference(BedHeight[] pair) {

        TDoubleArrayList stations = pair[0].getStations();
        TDoubleArrayList diffRes = new TDoubleArrayList();
        TDoubleArrayList kms = new TDoubleArrayList();
        TDoubleArrayList morphs = new TDoubleArrayList();
        TDoubleArrayList absolute = new TDoubleArrayList();
        TDoubleArrayList gap = new TDoubleArrayList();
        TDoubleArrayList heights1 = new TDoubleArrayList();
        TDoubleArrayList heights2 = new TDoubleArrayList();

        BedHeightSingle s1 = (BedHeightSingle)pair[0];
        BedHeightSingle s2 = (BedHeightSingle)pair[1];
        int range = s1.getYear() - s2.getYear();
        if (range  < 0) {
            range = range * -1;
        }
        for (int i = 0; i < stations.size(); i++) {
            if (!Double.isNaN(s1.getHeight(stations.get(i))) &&
                !Double.isNaN(s2.getHeight(stations.get(i)))) {
                double hDiff =
                    s1.getHeight(stations.get(i)) -
                    s2.getHeight(stations.get(i));
                diffRes.add(hDiff);
                double km = stations.get(i);
                kms.add(km);
                if (s1.getMorphWidth(km) >
                    s2.getMorphWidth(km)) {
                    morphs.add(s1.getMorphWidth(km));
                }
                else {
                    morphs.add(s2.getMorphWidth(km));
                }
                if (s1.getDataGap(km) > s2.getDataGap(km)) {
                    gap.add(s1.getDataGap(km));
                }
                else {
                    gap.add(s2.getDataGap(km));
                }
                absolute.add((hDiff / range) * 100);
                heights1.add(s1.getHeight(km));
                heights2.add(s2.getHeight(km));
            }
        }
        return new BedDiffYearResult(
            kms,
            diffRes,
            heights1,
            heights2,
            morphs,
            absolute,
            gap,
            s1.getYear(),
            s2.getYear());
    }
}