package org.simantics.maps.elevation.server;

import java.awt.geom.Rectangle2D;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.Collection;

import org.simantics.maps.elevation.server.prefs.MapsElevationServerPreferences;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class SingletonTiffTileInterface {

    private static final Logger LOGGER = LoggerFactory.getLogger(SingletonTiffTileInterface.class);

    private static SingletonTiffTileInterface instance;
    private TiffTileInterface tileInterface;

    static {
        // register spis
        Activator.registerSpis();
    }
    
    private SingletonTiffTileInterface() {
        Path tilesFolder = Paths.get(MapsElevationServerPreferences.tifFolderPath());
        try {
            Files.createDirectories(tilesFolder);
        } catch (IOException e) {
            LOGGER.error("Could not create directories {}", tilesFolder.toAbsolutePath(), e);
        }
        LOGGER.info("Elevation server looking for tif files at {}", tilesFolder.toAbsolutePath());
        tileInterface = new TiffTileInterface(tilesFolder);
    }

    private static SingletonTiffTileInterface getInstance() {
        if (instance == null ) {
            synchronized (SingletonTiffTileInterface.class) {
                if (instance == null) {
                    instance = new SingletonTiffTileInterface();
                }
            }
        }
        return instance;
    }

    public static synchronized void reloadElevationServer() {
        if (instance != null) {
            try {
                instance.tileInterface.close();
            } catch (IOException e) {
                LOGGER.error("Could not close current elevation server interface", e);
            } finally {
                instance = null;
            }
        }
        // let's re-initialize
        getInstance();
    }
    
    public static double lookupd(double x, double y) {
        return lookup(x, y).doubleValue();
    }

    public static Number lookup(double x, double y) {
        return getInstance().tileInterface.lookup(x, y);
    }

    public static Collection<Rectangle2D> getBoundingBoxes() {
        return getInstance().tileInterface.getBoundingBoxes();
    }
}