package demo.common;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;

import org.apache.commons.lang.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hsqldb.Server;
import org.springframework.util.FileCopyUtils;

/**
 * 该类的职责是在WebApp启动时自动开启HSQL服务. 依然使用Server方式，不受AppServer的影响.
 * 
 * @author frank
 * @author calvin
 */
public class HsqlListener implements ServletContextListener {
	protected static Log logger = LogFactory.getLog(HsqlListener.class);

	private final static String DEFAULT_DB_PATH = "{user.home}/db";

	private final static String DEFAULT_DB_SOURCE_SCRIPT = "default/default_db.script";

	private final static String DEFAULT_DB_SOURCE_PROPERTIES = "default/default_db.properties";

	
	Server server;
	
	public void contextInitialized(ServletContextEvent sce) {
		logger.info("HsqlListener initialize...");

		String dbName = sce.getServletContext().getInitParameter("hsql.dbName");

		String reset = sce.getServletContext().getInitParameter("hsql.reset");

		int port = -1;
		try {
			port = Integer.parseInt(sce.getServletContext().getInitParameter(
					"hsql.port"));
		} catch (Exception e) {
		}

		if (StringUtils.isEmpty(dbName)) {
			logger.error("Cant' get hsqldb.dbName from web.xml Context Param");
			return;
		}

		String path = getDbPath(sce);

		File dbDir = new File(path);
		if (!dbDir.exists()) {
			logger.info("Create Path:" + path);
			if (!dbDir.mkdirs()) {
				logger.error("Can not create DB Dir for Hsql:" + dbDir);
				return;
			}
		}

		if (!path.endsWith("/")) {
			path = path + "/";
		}
		
		File scriptFile = new File(path + dbName + ".script");
		File propertiesFile = new File(path + dbName + ".properties");
		if (reset.equals("1") || reset.equalsIgnoreCase("true")
				|| !scriptFile.exists()) {
			logger.info("Create DataFile:" + scriptFile.getPath());
			try {
				FileCopyUtils.copy(new FileInputStream(path
						+ DEFAULT_DB_SOURCE_SCRIPT), new FileOutputStream(
						scriptFile));
				FileCopyUtils.copy(new FileInputStream(path
						+ DEFAULT_DB_SOURCE_PROPERTIES), new FileOutputStream(
						propertiesFile));
			} catch (IOException e) {
				logger.error("Copy Default script file error");
				return;
			}
		}

		startServer(path, dbName, port);
	}

	private String getDbPath(ServletContextEvent sce) {
		String path = sce.getServletContext().getInitParameter("hsql.dbPath");

		if (StringUtils.isEmpty(path)) {
			path = DEFAULT_DB_PATH;
		}
		if (path.startsWith("{user.home}")) {
			path = path.replaceFirst("\\{user.home\\}", System.getProperty(
					"user.home").replace('\\', '/'));
		}
		if (path.startsWith("{webapp.root}")) {
			path = path.replaceFirst("\\{webapp.root\\}", sce
					.getServletContext().getRealPath("/").replace('\\', '/'));
		}
		return path;
	}

	private void startServer(String dbPath, String dbName, int port) {
		try {
		server = new Server();
		server.setDatabaseName(0, dbName);
		System.out.println(dbPath + dbName);
		server.setDatabasePath(0, dbPath + dbName);
		if (port != -1) {
			server.setPort(port);
		}
		
//		server.setSilent(true);
		server.start();
		
		// 等待Server启动

			Thread.sleep(1000);
		} catch (Exception e) {
			// do nothing
		}
		logger.info("hsqldb started...");
	}

	public void contextDestroyed(ServletContextEvent sce) {
		try {
			server.shutdown();
			server.stop();

			Thread.sleep(2000);
		} catch (InterruptedException e) {
			// do nothing
		}
		logger.info("hsqldb stoped...");

	}
}