package de.intevation.flys.utils;

import com.vividsolutions.jts.geom.Envelope;
import com.vividsolutions.jts.geom.LineString;

import de.intevation.flys.artifacts.model.LayerInfo;
import de.intevation.flys.artifacts.model.RiverFactory;
import de.intevation.flys.model.River;
import de.intevation.flys.model.RiverAxis;

import java.io.File;
import java.io.FileNotFoundException;
import java.util.ArrayList;
import java.util.List;

import org.apache.log4j.Logger;
import org.apache.velocity.Template;

public class RiverMapfileGenerator extends MapfileGenerator {

    public static final String XPATH_RIVERMAP_RIVER_PROJECTION =
            "/artifact-database/rivermap/river[@name=$name]/srid/@value";

    public static final String XPATH_RIVERMAP_SHAPEFILE_DIR =
            "/artifact-database/rivermap/shapefile-path/@value";

    public static final String XPATH_RIVERMAP_VELOCITY_LOGFILE =
            "/artifact-database/rivermap/velocity/logfile/@path";

    public static final String XPATH_RIVERMAP_MAPSERVER_URL =
            "/artifact-database/rivermap/mapserver/server/@path";

    public static final String XPATH_RIVERMAP_MAPFILE_PATH =
            "/artifact-database/rivermap/mapserver/mapfile/@path";

    public static final String XPATH_RIVERMAP_MAPFILE_TEMPLATE =
            "/artifact-database/rivermap/mapserver/map-template/@path";

    public static final String XPATH_RIVERMAP_MAPSERVER_TEMPLATE_PATH =
            "/artifact-database/rivermap/mapserver/templates/@path";

    private static Logger logger = Logger.getLogger(RiverMapfileGenerator.class);

    /**
     * Generate river axis mapfile.
     */
    @Override
    public void generate() {
        logger.debug("generate()");

        List<River>  rivers     = RiverFactory.getRivers();
        List<String> riverFiles = new ArrayList<String>();

        for (River river : rivers) {
            // We expect that every river has only one RiverAxis.
            // This is not correct but currently the case here, see
            // RiverAxis.java.
            List<RiverAxis> riverAxis = RiverAxis.getRiverAxis(river.getName());
            if (riverAxis == null) {
                logger.warn("River " + river.getName() + " has no river axis!");
                continue;
            }
            LineString geom = riverAxis.get(0).getGeom();
            Envelope extent = geom.getEnvelopeInternal();

            createRiverAxisLayer(
                    river.getName(),
                    river.getId(),
                    Integer.toString(geom.getSRID()),
                    extent.getMinX() + " " +
                    extent.getMinY() + " " +
                    extent.getMaxX() + " " +
                    extent.getMaxY());

            riverFiles.add("river-" + river.getName() + ".map");
        }
        writeMapfile(riverFiles);
    }

    protected void createRiverAxisLayer(String riverName, int riverID, String srid, String extend) {
        LayerInfo layerInfo = new LayerInfo();
        layerInfo.setName(riverName);
        layerInfo.setSrid(srid);
        layerInfo.setExtent(extend);
        layerInfo.setType("line");
        layerInfo.setData("geom FROM river_axes");      // FIXME: Use templates for that
        layerInfo.setFilter("river_id = " + riverID);
        layerInfo.setTitle(riverName + " RiverAxis");

        File layerFile = new File("river-" + riverName + ".map");
        Template template = getTemplateByName("riveraxis-layer.vm");
        if (template == null) {
            logger.warn("Template riveraxis-layer.vm not found.");
            return;
        }

        try {
            writeLayer(layerInfo, layerFile, template);
        }
        catch (FileNotFoundException e) {
            logger.warn(e.getLocalizedMessage(), e);
        }
    }

    @Override
    protected String getVelocityLogfile() {
        return FLYSUtils.getXPathString(XPATH_RIVERMAP_VELOCITY_LOGFILE);
    }

    @Override
    protected String getMapserverTemplatePath() {
        return FLYSUtils.getXPathString(XPATH_RIVERMAP_MAPSERVER_TEMPLATE_PATH);
    }

    @Override
    protected String getMapserverUrl() {
        return FLYSUtils.getXPathString(XPATH_RIVERMAP_MAPSERVER_URL);
    }

    @Override
    protected String getMapfilePath() {
        return FLYSUtils.getXPathString(XPATH_RIVERMAP_MAPFILE_PATH);
    }

    @Override
    protected String getMapfileTemplate() {
        return FLYSUtils.getXPathString(XPATH_RIVERMAP_MAPFILE_TEMPLATE);
    }
}