AstroConfig.java

/**
 * Copyright (c) 2010-2016 by the respective copyright holders.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 */
package org.openhab.binding.astro.internal.common;

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Dictionary;
import java.util.TimeZone;

import org.apache.commons.lang.StringUtils;
import org.apache.commons.lang.builder.ToStringBuilder;
import org.apache.commons.lang.builder.ToStringStyle;
import org.osgi.service.cm.ConfigurationException;

/**
 * Parses the config in openhab.cfg.
 *
 * <pre>
 * ############################## Astro Binding ##############################
 * #
 * # The latitude
 * astro:latitude=nn.nnnnnn
 *
 * # The longitude
 * astro:longitude=nn.nnnnnn
 *
 * # Refresh interval for sun azimuth/elevation and moon distance/illumination calculation in seconds (optional, defaults to disabled)
 * astro:interval=nnn
 * </pre>
 *
 * @author Gerhard Riegler
 * @since 1.5.0
 */
public class AstroConfig {
    private static final String CONFIG_KEY_LATITUDE = "latitude";
    private static final String CONFIG_KEY_LONGITUDE = "longitude";
    private static final String CONFIG_KEY_INTERVAL = "interval";

    private double latitude;
    private double longitude;
    private int interval;
    private boolean valid;

    /**
     * Parses and validates the properties in the openhab.cfg.
     */
    public void parse(Dictionary<String, ?> properties) throws ConfigurationException {
        valid = false;

        String cfgLatitude = (String) properties.get(AstroConfig.CONFIG_KEY_LATITUDE);
        String cfgLongitude = (String) properties.get(AstroConfig.CONFIG_KEY_LONGITUDE);

        if (StringUtils.isBlank(cfgLatitude) || StringUtils.isBlank(cfgLongitude)) {
            throw new ConfigurationException("astro",
                    "Parameters latitude and longitude are mandatory and must be configured. Please check your openhab.cfg!");
        }

        try {
            latitude = Double.parseDouble(cfgLatitude);
            longitude = Double.parseDouble(cfgLongitude);
        } catch (NumberFormatException ex) {
            throw new ConfigurationException("astro",
                    "Parameters latitude and/or longitude in wrong format. Please check your openhab.cfg!");
        }

        interval = parseInt(properties, CONFIG_KEY_INTERVAL, 0);

        valid = true;
    }

    /**
     * Parses a integer property.
     */
    private Integer parseInt(Dictionary<String, ?> properties, String key, Integer defaultValue)
            throws ConfigurationException {
        String value = (String) properties.get(key);
        if (StringUtils.isNotBlank(value)) {
            try {
                return Integer.parseInt(value);
            } catch (NumberFormatException ex) {
                throw new ConfigurationException("astro",
                        "Parameter " + key + " in wrong format. Please check your openhab.cfg!");
            }

        } else {
            return defaultValue;
        }
    }

    /**
     * Returns true if the AstroConfig has valid parameters.
     */
    public boolean isValid() {
        return valid;
    }

    /**
     * Returns the specified latitude.
     */
    public double getLatitude() {
        return latitude;
    }

    /**
     * Returns the specified longitude.
     */
    public double getLongitude() {
        return longitude;
    }

    /**
     * Returns the specified interval.
     */
    public int getInterval() {
        return interval;
    }

    @Override
    public String toString() {
        String intervallMessage = (interval == 0 ? "disabled" : String.valueOf(interval));

        TimeZone tz = TimeZone.getDefault();
        StringBuilder tzInfo = new StringBuilder();
        tzInfo.append(tz.getID());
        tzInfo.append(" (").append(tz.getDisplayName(false, TimeZone.SHORT)).append(" ")
                .append(new SimpleDateFormat("Z").format(Calendar.getInstance().getTime()));
        tzInfo.append(")");
        return new ToStringBuilder(this, ToStringStyle.SHORT_PREFIX_STYLE).append("latitude", latitude)
                .append("longitude", longitude).append("interval", intervallMessage)
                .append("systemTimezone", tzInfo.toString())
                .append("daylightSavings", Calendar.getInstance().get(Calendar.DST_OFFSET) != 0).toString();
    }
}