/** Copyright (C) 2017 by Bundesanstalt für Gewässerkunde
 * Software engineering by
 *  Björnsen Beratende Ingenieure GmbH
 *  Dr. Schumacher Ingenieurbüro für Wasser und Umwelt
 *
 * This file is Free Software under the GNU AGPL (>=v3)
 * and comes with ABSOLUTELY NO WARRANTY! Check out the
 * documentation coming with Dive4Elements River for details.
 */
package org.dive4elements.river.artifacts.sinfo.common;

import java.io.OutputStream;
import java.text.DateFormat;
import java.text.NumberFormat;
import java.util.Collection;
import java.util.Date;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;

import org.apache.commons.lang.math.DoubleRange;
import org.apache.log4j.Logger;
import org.dive4elements.artifacts.CallMeta;
import org.dive4elements.artifacts.common.utils.Config;
import org.dive4elements.river.FLYS;
import org.dive4elements.river.artifacts.model.CalculationResult;
import org.dive4elements.river.artifacts.resources.Resources;
import org.dive4elements.river.artifacts.sinfo.SInfoI18NStrings;
import org.dive4elements.river.artifacts.sinfo.util.BedHeightInfo;
import org.dive4elements.river.artifacts.sinfo.util.MetaAndTableJRDataSource;
import org.dive4elements.river.artifacts.sinfo.util.RiverInfo;
import org.dive4elements.river.artifacts.sinfo.util.WstInfo;
import org.dive4elements.river.exports.AbstractExporter;

import au.com.bytecode.opencsv.CSVWriter;
import net.sf.jasperreports.engine.JRDataSource;
import net.sf.jasperreports.engine.JRException;
import net.sf.jasperreports.engine.JasperExportManager;
import net.sf.jasperreports.engine.JasperFillManager;
import net.sf.jasperreports.engine.JasperPrint;

/**
 * @author Gernot Belger
 */
public abstract class AbstractSInfoExporter<RESULT extends AbstractSInfoCalculationResult, RESULTS extends AbstractSInfoCalculationResults<RESULT>> extends AbstractExporter {

    private static final String CSV_META_HEADER_SOUNDING = "sinfo.export.flow_depth.csv.meta.header.sounding";

    private static final String CSV_META_HEADER_SOUNDING_YEAR = "sinfo.export.flow_depth.csv.meta.header.sounding.year";

    private static final String CSV_META_HEADER_SOUNDING_TYPE = "sinfo.export.flow_depth.csv.meta.header.sounding.type";

    private static final String CSV_META_HEADER_SOUNDING_EVALUATOR = "sinfo.export.flow_depth.csv.meta.header.sounding.evaluator";

    private static final String CSV_META_HEADER_SOUNDING_PRJ = "sinfo.export.flow_depth.csv.meta.header.sounding.prj";

    private static final String CSV_META_HEADER_SOUNDING_ELEVATIOIN_MODEL = "sinfo.export.flow_depth.csv.meta.header.sounding.elevationmodel";

    private static final String CSV_META_HEADER_SOUNDING_ELEVATIOIN_MODEL_ORIGINAL = "sinfo.export.flow_depth.csv.meta.header.sounding.elevationmodel.original";

    /** The storage that contains the current calculation result. */
    private RESULTS data = null;

    protected abstract Logger getLog();

    public RESULTS getData() {
        return this.data;
    }

    @Override
    protected final void addData(final Object d) {
        /* reset */
        this.data = null;

        if (d instanceof CalculationResult) {

            final Object dat = ((CalculationResult) d).getData();
            if (dat != null) {
                @SuppressWarnings("unchecked")
                final RESULTS result = (RESULTS) dat;
                this.data = result;
            }
        }
    }

    /**
     * Formats header with unit and label: msg [unit] (label)
     */
    protected final String msgUnitLabel(final String key, final String unit, final String label) {
        final String msg = msg(key);
        return String.format("%s [%s] (%s)", msg, unit, label);
    }

    @Override
    protected final void writeCSVData(final CSVWriter writer) {
        getLog().info("writeCSVData");

        /* fetch calculation results */
        final RESULTS results = this.data;

        final RiverInfo river = results.getRiver();

        /* write as csv */
        writeCSVGlobalMetadata(writer, results);
        writeCSVHeader(writer, results, river);

        for (final RESULT result : results.getResults()) {
            writeCSVResult(writer, results, result);
        }
    }

    protected abstract void writeCSVHeader(final CSVWriter writer, final RESULTS results, final RiverInfo river);

    /**
     * Add metadata that is once written to the top of the file.
     */
    protected abstract void writeCSVGlobalMetadata(final CSVWriter writer, final RESULTS results);

    protected final void writeCSVMetaEntry(final CSVWriter writer, final String message, final Object... messageArgs) {

        final CallMeta meta = this.context.getMeta();

        writer.writeNext(new String[] { Resources.getMsg(meta, message, message, messageArgs) });
    }

    protected final void writeCSVResult(final CSVWriter writer, final RESULTS results, final RESULT result) {

        writeCSVResultMetadata(writer, results, result);

        /* nwo the value rows */
        final Collection<SInfoResultRow> rows = result.getRows();
        for (final SInfoResultRow row : rows) {
            writeCSVRow(writer, results, result, row);
        }
    }

    /**
     * Add metadata that is written once per result set.
     */
    protected abstract void writeCSVResultMetadata(CSVWriter writer, RESULTS results, RESULT result);

    protected final void writeCSVRow(final CSVWriter writer, final RESULTS results, final RESULT result, final SInfoResultRow row) {
        getLog().debug("writeCSVFlowDepthRow");

        final String[] formattedRow = formatCSVRow(results, result, row);
        writer.writeNext(formattedRow);
    }

    protected abstract String[] formatCSVRow(RESULTS results, RESULT result, final SInfoResultRow row);

    @Override
    protected final void writePDF(final OutputStream outStream) {
        getLog().debug("write PDF");

        final JRDataSource source = createJRData();

        final String confPath = Config.getConfigDirectory().toString();

        // FIXME: distinguish between with and without tkh: we need two jasper reports!

        final Map<String, Object> parameters = new HashMap<>();
        parameters.put("ReportTitle", "Exported Data");

        try {
            final String jasperPath = confPath + getJasperFile();

            final JasperPrint print = JasperFillManager.fillReport(jasperPath, parameters, source);
            JasperExportManager.exportReportToPdfStream(print, outStream);
        }
        catch (final JRException je) {
            getLog().warn("Error generating PDF Report!", je);
        }
    }

    protected abstract String getJasperFile();

    private JRDataSource createJRData() {

        /* fetch calculation results */
        final RESULTS results = this.data;

        final MetaAndTableJRDataSource source = new MetaAndTableJRDataSource();

        addJRMetaData(source, results);

        for (final RESULT result : results.getResults()) {
            addJRTableData(source, results, result);
        }

        return source;
    }

    protected abstract void addJRMetaData(final MetaAndTableJRDataSource source, final RESULTS results);

    protected final void addJRTableData(final MetaAndTableJRDataSource source, final RESULTS results, final RESULT result) {

        final Collection<SInfoResultRow> rows = result.getRows();

        for (final SInfoResultRow row : rows) {

            final String[] formattedRow = formatPDFRow(results, row);
            source.addData(formattedRow);
        }
    }

    protected abstract String[] formatPDFRow(RESULTS results, final SInfoResultRow row);

    protected final void writeCSVGlobalMetadataDefaults(final CSVWriter writer, final AbstractSInfoCalculationResults<?> results) {

        final String calcModeLabel = results.getCalcModeLabel();
        final RiverInfo river = results.getRiver();
        final DoubleRange calcRange = results.getCalcRange();

        writeCSVMetaEntry(writer, SInfoI18NStrings.CSV_META_HEADER_RESULT, msg(SInfoI18NStrings.CSV_META_HEADER_RESULT_LABEL), river.getName(), calcModeLabel);

        // "# FLYS-Version: "
        writeCSVMetaEntry(writer, SInfoI18NStrings.CSV_META_VERSION, msg(SInfoI18NStrings.CSV_META_VERSION_LABEL), FLYS.VERSION);

        // "# Bearbeiter: "
        writeCSVMetaEntry(writer, SInfoI18NStrings.CSV_META_USER, msg(SInfoI18NStrings.CSV_META_USER_LABEL), results.getUser());

        // "# Datum der Erstellung: "
        final Locale locale = Resources.getLocale(this.context.getMeta());
        final DateFormat df = DateFormat.getDateInstance(DateFormat.SHORT, locale);
        writeCSVMetaEntry(writer, SInfoI18NStrings.CSV_META_CREATION, msg(SInfoI18NStrings.CSV_META_CREATION_LABEL), df.format(new Date()));

        // "# Gewässer: "
        writeCSVMetaEntry(writer, SInfoI18NStrings.CSV_META_RIVER, msg(SInfoI18NStrings.CSV_META_RIVER_LABEL), river.getName());

        // "# Höhensystem des Flusses: "
        writeCSVMetaEntry(writer, SInfoI18NStrings.CSV_META_HEIGHT_UNIT_RIVER, river.getWstUnit());

        // "# Ort/Bereich (km): "
        writeCSVMetaEntry(writer, SInfoI18NStrings.CSV_META_RANGE, msg(SInfoI18NStrings.CSV_META_RANGE_LABEL),
                getKmFormatter().format(calcRange.getMinimumDouble()), getKmFormatter().format(calcRange.getMaximumDouble()));
    }

    protected final void writeCSVSoundingMetadata(final CSVWriter writer, final BedHeightInfo sounding) {
        writeCSVSoundingMetadata(writer, sounding, CSV_META_HEADER_SOUNDING);
    }

    protected final void writeCSVSoundingMetadata(final CSVWriter writer, final BedHeightInfo sounding, final String mainLabel) {
        // "##METADATEN PEILUNG"
        writeCSVMetaEntry(writer, mainLabel);

        // "# Jahr der Peilung: "
        writeCSVMetaEntry(writer, CSV_META_HEADER_SOUNDING_YEAR, Integer.toString(sounding.getYear()));
        // "# Aufnahmeart: "
        writeCSVMetaEntry(writer, CSV_META_HEADER_SOUNDING_TYPE, sounding.getType());
        // "# Auswerter: "
        writeCSVMetaEntry(writer, CSV_META_HEADER_SOUNDING_EVALUATOR, sounding.getEvaluationBy());
        // "# Lagesystem: "
        writeCSVMetaEntry(writer, CSV_META_HEADER_SOUNDING_PRJ, sounding.getLocationSystem());
        // "# Höhensystem: "
        writeCSVMetaEntry(writer, CSV_META_HEADER_SOUNDING_ELEVATIOIN_MODEL, sounding.getCurElevationModelUnit());
        // "# ursprüngliches Höhensystem: "
        writeCSVMetaEntry(writer, CSV_META_HEADER_SOUNDING_ELEVATIOIN_MODEL_ORIGINAL, sounding.getOldElevationModelUnit());
    }

    protected final void writeCSVWaterlevelMetadata(final CSVWriter writer, final WstInfo wst) {
        writeCSVWaterlevelMetadata(writer, wst, SInfoI18NStrings.CSV_META_HEADER_WATERLEVEL);
    }

    protected final void writeCSVWaterlevelMetadata(final CSVWriter writer, final WstInfo wst, final String mainLabel) {
        // "##METADATEN WASSERSPIEGELLAGE"
        writeCSVMetaEntry(writer, mainLabel);

        // "# Bezeichnung der Wasserspiegellage: "
        writeCSVMetaEntry(writer, SInfoI18NStrings.CSV_META_HEADER_WATERLEVEL_NAME, wst.getLabel());

        // "# Bezugspegel: "
        writeCSVMetaEntry(writer, SInfoI18NStrings.CSV_META_HEADER_WATERLEVEL_GAUGE, wst.getGauge());

        // "# Jahr/Zeitraum der Wasserspiegellage: "
        final int year = wst.getYear();
        if (year > 0)
            writeCSVMetaEntry(writer, SInfoI18NStrings.CSV_META_HEADER_WATERLEVEL_YEAR, Integer.toString(year));
    }

    protected final void addJRMetaDataDefaults(final MetaAndTableJRDataSource source, final AbstractSInfoCalculationResults<?> results) {

        final RiverInfo river = results.getRiver();
        final String wstUnitName = river.getWstUnit();

        source.addMetaData("header", msg(SInfoI18NStrings.CSV_META_HEADER_RESULT_LABEL));
        source.addMetaData("calcMode", results.getCalcModeLabel());

        source.addMetaData("version_label", msg(SInfoI18NStrings.CSV_META_VERSION_LABEL));
        source.addMetaData("version", FLYS.VERSION);

        source.addMetaData("user_label", msg(SInfoI18NStrings.CSV_META_USER_LABEL));
        source.addMetaData("user", results.getUser());

        final Locale locale = Resources.getLocale(this.context.getMeta());
        final DateFormat df = DateFormat.getDateInstance(DateFormat.SHORT, locale);
        source.addMetaData("date_label", msg(SInfoI18NStrings.CSV_META_CREATION_LABEL));
        source.addMetaData("date", df.format(new Date()));

        source.addMetaData("river_label", msg(SInfoI18NStrings.CSV_META_RIVER_LABEL));
        source.addMetaData("river", river.getName());
        source.addMetaData("river_unit", wstUnitName);

        final DoubleRange calcRange = results.getCalcRange();
        final NumberFormat kmFormatter = getKmFormatter();
        final String rangeValue = String.format("%s - %s", kmFormatter.format(calcRange.getMinimumDouble()), kmFormatter.format(calcRange.getMaximumDouble()));
        source.addMetaData("range_label", msg(SInfoI18NStrings.CSV_META_RANGE_LABEL));
        source.addMetaData("range", rangeValue);
    }
}