Configuration.java

/*
 * This file is part of the aidGer project.
 *
 * Copyright (C) 2010-2013 The aidGer Team
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package de.aidger.utils;

import static de.aidger.utils.Translation._;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.text.MessageFormat;
import java.util.Properties;

import de.aidger.model.Runtime;

/**
 * Gets and sets the settings
 * 
 * @author aidGer Team
 */
public final class Configuration {

    /**
     * The settings of the program.
     */
    private final Properties properties = new Properties();

    /**
     * The file name of the configuration.
     */
    private final String file;

    /**
     * The current version of the configuration file.
     */
    private static final int version = 2;

    /**
     * Initializes the Configuration.
     */
    public Configuration() {
        this("settings.cfg");
    }

    /**
     * Initializes the Configuration with a given filename.
     * 
     * @param filename
     *            The filename of the configuration.
     */
    public Configuration(String filename) {
        file = Runtime.getInstance().getConfigPath() + filename;

        /* Check if the configuration exists and create it if it does not */
        File config = new File(file);
        if (!config.exists()) {
            createFile();
        } else {
            /* Read the settings from the file. */
            try {
                FileInputStream inputStream = new FileInputStream(config);
                properties.load(inputStream);
                inputStream.close();
            } catch (Exception e) {
                createFile();
            }
        }

        /* Get the version of the config and migrate if necessary */
        String confVersion = get("config-version");
        if (confVersion == null) {
            migrate(0);
        } else if (Integer.parseInt(confVersion) < version) {
            migrate(Integer.parseInt(confVersion));
        }
    }

    /**
     * Gets the value of a property.
     * 
     * @param option
     *            The property of which to get the value from
     * @return The value of the specified property.
     */
    public String get(String option) {
        return properties.getProperty(option);
    }

    /**
     * Sets the value of a property.
     * 
     * @param option
     *            The property to change.
     * @param value
     *            The value to change the property to.
     */
    public void set(String option, String value) {
        properties.setProperty(option, value);

        try {
            File outputFile = new File(file);
            FileOutputStream outputStream = new FileOutputStream(outputFile);
            properties.store(outputStream, "");
            outputStream.close();
        } catch (Exception e) {
            createFile();
        }
    }

    /**
     * Remove an option from the config.
     * 
     * @param option
     *            The option to remove
     */
    public void remove(String option) {
        properties.remove(option);

        try {
            File outputFile = new File(file);
            FileOutputStream outputStream = new FileOutputStream(outputFile);
            properties.store(outputStream, "");
            outputStream.close();
        } catch (Exception e) {
            createFile();
        }
    }

    /**
     * Writes the default settings to the settings file.
     */
    private void createFile() {
        try {
            File outputFile = new File(file);
            FileOutputStream outputStream = new FileOutputStream(outputFile);
            migrate(0);
            properties.store(outputStream, "");
            outputStream.close();
        } catch (Exception e) {
            Logger.error(MessageFormat.format(
                _("Could not create file \"{0}\"."), new Object[] { file }));
        }
    }

    /**
     * Migrate an old configuration file to the current version.
     * 
     * @param oldVersion
     *            The version of the config file
     */
    private void migrate(int oldVersion) {
        if (oldVersion < 1 && properties.getProperty("name") == null) {
            properties.setProperty("name", "");
            properties.setProperty("pdf-viewer", "");
            properties.setProperty("activities", "10");
            properties.setProperty("auto-open", "n");
            properties.setProperty("auto-save", "n");
            properties.setProperty("pessimistic-factor", "1.0");
            properties.setProperty("historic-factor", "1.0");
            properties.setProperty("anonymize-time", "365");
            properties.setProperty("tolerance", "0.0");
            properties.setProperty("calc-method", "1");
            properties.setProperty("rounding", "2");
            properties.setProperty("debug", "false");
        }
        if (oldVersion < 2) {
            properties.setProperty("database-driver", "com.mysql.jdbc.Driver");
            properties.setProperty("database-uri", "jdbc:mysql://localhost/aidger?user=root&password=");
        }

        properties.setProperty("config-version", Integer.toString(version));
    }
}