package de.intevation.flys.exports;

import java.io.OutputStream;
import java.text.NumberFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import org.w3c.dom.Document;

import org.apache.log4j.Logger;

import au.com.bytecode.opencsv.CSVWriter;

import de.intevation.artifacts.CallContext;

import de.intevation.flys.artifacts.model.WQDay;
import de.intevation.flys.utils.Formatter;


/**
 * @author <a href="mailto:ingo.weinzierl@intevation.de">Ingo Weinzierl</a>
 */
public class DurationCurveExporter extends AbstractExporter {

    /** The logger used in this exporter.*/
    private static Logger logger = Logger.getLogger(WaterlevelExporter.class);


    public static final String CSV_DURATION_HEADER =
        "export.duration.curve.csv.header.duration";

    public static final String CSV_W_HEADER =
        "export.duration.curve.csv.header.w";

    public static final String CSV_Q_HEADER =
        "export.duration.curve.csv.header.q";

    public static final String DEFAULT_CSV_DURATION_HEADER = "D [Tagen]";
    public static final String DEFAULT_CSV_W_HEADER  = "W [NN + m]";
    public static final String DEFAULT_CSV_Q_HEADER  = "Q [m\u00b3/s]";


    /** The storage that contains all WQKms objects for the different facets.*/
    protected List<WQDay> data;


    public void init(Document request, OutputStream out, CallContext context) {
        logger.debug("DurationCurveExporter.init");

        super.init(request, out, context);

        this.data = new ArrayList<WQDay>();
    }


    @Override
    protected void addData(Object d) {
        if (d instanceof WQDay []) {
            data.addAll(Arrays.asList((WQDay [])d));
        }
    }


    protected void writeCSVData(CSVWriter writer) {
        logger.info("DurationCurveExporter.writeData");

        writeCSVHeader(writer);

        for (WQDay wqday: data) {
            wQDay2CSV(writer, wqday);
        }
    }


    protected void writeCSVHeader(CSVWriter writer) {
        logger.info("DurationCurveExporter.writeCSVHeader");

        writer.writeNext(new String[] {
            msg(CSV_W_HEADER, DEFAULT_CSV_W_HEADER),
            msg(CSV_Q_HEADER, DEFAULT_CSV_Q_HEADER),
            msg(CSV_DURATION_HEADER, DEFAULT_CSV_DURATION_HEADER)
        });
    }


    protected void wQDay2CSV(CSVWriter writer, WQDay wqday) {
        logger.debug("DurationCurveExporter.wQDay2CSV");

        int size = wqday.size();

        NumberFormat wf  = getWFormatter();
        NumberFormat qf  = getQFormatter();
        NumberFormat df  = getDFormatter();

        for (int i = 0; i < size; i ++) {
            writer.writeNext(new String[] {
                wf.format(wqday.getW(i)),
                qf.format(wqday.getQ(i)),
                df.format(wqday.getDay(i))
            });
        }
    }


    /**
     * Returns the number formatter for W values.
     *
     * @return the number formatter for W values.
     */
    protected NumberFormat getWFormatter() {
        return Formatter.getDurationW(context);
    }


    /**
     * Returns the number formatter for Q values.
     *
     * @return the number formatter for Q values.
     */
    protected NumberFormat getQFormatter() {
        return Formatter.getDurationQ(context);
    }


    /**
     * Returns the number formatter for duration values.
     *
     * @return the number formatter for duration values.
     */
    protected NumberFormat getDFormatter() {
        return Formatter.getDurationD(context);
    }
}