/*
 * Copyright @ 2013 CurisTEC, S.A.S. All Rights Reserved.
 */
package net.curisit.securis;

import java.io.IOException;
import java.text.MessageFormat;
import java.util.Properties;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

/**
 * AppVersion
 * <p>
 * This class allows to read a version.properties file with information about
 * application version This properties file is created automatically during
 * compilation process. The source of this information is the version string
 * inside pom.xml file. Format version has this format:
 * {majorVersion}.{minorVersion}.{incrementalVersion}[-{qualifier}]
 * 
 * @author cesar 
 * Last reviewed by JRA on Oct 5, 2025.
 */
public class AppVersion {

	private static AppVersion instance;
	private Properties prop;

	private static final String PROPERTIES_FILE_NAME = "/version.properties";
	private static final Logger LOG = LogManager.getLogger(AppVersion.class);

	/**
	 * AppVersion<p>
	 * Constructor
	 */
	private AppVersion() {
		prop = new Properties();
		try {
			prop.load(getClass().getResourceAsStream(PROPERTIES_FILE_NAME));
		} catch (IOException e) {
			LOG.error("Version file is missing", e);
		}
	}

	/**
	 * getInstance<p>
	 * Get unique instance
	 * 
	 * @return instance
	 */
	public synchronized static AppVersion getInstance() {
		if (instance == null) {
			instance = new AppVersion();
		}
		return instance;
	}

	/**
	 * getMajorVersion<p>
	 * Returns the major version
	 * 
	 * @return majorVersion
	 */
	public Integer getMajorVersion() {
		return getParamAsInt(Keys.MAJOR_VERSION, -1);
	}

	/**
	 * getMinorVersion<p>
	 * Return the minor version
	 * 
	 * @return minorVersion
	 */
	public Integer getMinorVersion() {
		return getParamAsInt(Keys.MINOR_VERSION, -1);
	}

	/**
	 * getIncrementalVersion<p>
	 * Returns the incremental version
	 * 
	 * @return incrementalVersion
	 */
	public Integer getIncrementalVersion() {
		return getParamAsInt(Keys.INCREMENTAL_VERSION, -1);
	}

	/**
	 * getQualifier<p>
	 * Returns qualifier if it exists
	 * 
	 * @return qualifier
	 */
	public String getQualifier() {
		return getParam(Keys.QUALIFIER);
	}

	/**
	 * getCompleteVersion<p>
	 * Return complete version
	 * 
	 * @return completeVersion
	 */
	public String getCompleteVersion() {
		String strVersion = MessageFormat.format("{0}.{1}.{2}", getMajorVersion(), getMinorVersion(), getIncrementalVersion());
		if (getQualifier() != null && !getQualifier().isEmpty())
			strVersion = strVersion + "-" + getQualifier();
		return strVersion;
	}

	/*********************** Private methods *********************/

	/**
	 * getParam<p>
	 * Get the parameter associated with the key
	 * 
	 * @param key
	 * @return param
	 */
	private String getParam(String key) {
		return prop.getProperty(key, null);
	}

	/**
	 * getParamAsInt<p>
	 * Get the parameter as integer
	 * 
	 * @param key
	 * @param defaulValue
	 * @return paramAsInt
	 */
	private Integer getParamAsInt(String key, Integer defaulValue) {
		String value = getParam(key);
		try {
			if (value == null) {
				LOG.error("Wrong version field");
				return defaulValue;
			} else
				return Integer.parseInt(value);
		} catch (NumberFormatException e) {
			LOG.error("Wrong version field");
			return defaulValue;
		}
	}

	/**
	 * Keys<p>
	 * Application version keys
	 */
	private static class Keys {
		public static final String MAJOR_VERSION = "majorVersion";
		public static final String MINOR_VERSION = "minorVersion";
		public static final String INCREMENTAL_VERSION = "incrementalVersion";
		public static final String QUALIFIER = "qualifier";
	}

}