package foundation.server.config;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Iterator;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;


public class ConfigerLoader {

	protected static Logger logger;
	private static ConfigerLoader instance;

	static {
		logger = LogManager.getLogger(ConfigerLoader.class);
	}

	private ConfigerLoader() {
		
	}

	public synchronized static ConfigerLoader getInstance() {
		if (instance == null) {
			instance = new ConfigerLoader();
		}

		return instance;
	}
	
	public static void staticLoad() throws Exception {
		getInstance();
		instance.load();
	}

	public void load() throws Exception {
		//1. clear configuration
		Configer configer = Configer.newInstance();
		
		//2. load configuration
		String path = Configer.getPath_MainConfig();
		File file = new File(path);

		loadOneFile(configer, file);
		
		//3. 
		Configer.activeInstance(configer);
	}

	private void loadOneFile(Configer configer, File file) throws Exception {
		try {
			logger.debug("load config file:" + file);
			InputStream inputStream = new FileInputStream(file);

			try {
				SAXReader reader = new SAXReader();
				reader.setValidation(false);

				Document doc = reader.read(inputStream);
				Element root = doc.getRootElement();

				loadParams(configer, root);
			} 
			finally {
				try {
					inputStream.close();
				} catch (IOException e) {
				}
			}
		} catch (Exception e) {
			logger.error("can not load dispatch file: " + file);
			logger.error(e);
			throw e;
		}
	}
	
	private void loadParams(Configer configer, Element root) throws Exception {
		Iterator<?> iterator = root.elementIterator("param");

		while (iterator.hasNext()) {
			Element element = (Element) iterator.next();

			String name = element.attributeValue("name");
			String value = element.attributeValue("value");

			configer.addParam(name, value);
		}
	}

}