/*-
 * ============LICENSE_START=======================================================
 * org.openecomp.aai
 * ================================================================================
 * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
 * ================================================================================
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * ============LICENSE_END=========================================================
 */

/**
 * 
 */
package org.openecomp.aai.util;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.InetAddress;
import java.net.UnknownHostException;
import java.util.ArrayList;
import java.util.List;
import java.util.StringTokenizer;

import org.openecomp.aai.exceptions.AAIException;
import com.att.eelf.configuration.EELFLogger;
import com.att.eelf.configuration.EELFManager;


public class AAIRSyncUtility {

	private static final EELFLogger LOGGER = EELFManager.getInstance().getLogger(AAIRSyncUtility.class);	
	private final String DEFAULT_CHECK = new String("aai.primary.filetransfer.");
	
	/**
	 * Instantiates a new AAIR sync utility.
	 */
	public AAIRSyncUtility() {

	}

	/**
	 * Do command.
	 *
	 * @param command the command
	 * @return the int
	 * @throws Exception the exception
	 */
	public int doCommand(List<String> command)  
			  throws Exception 
	{ 
		String s = null; 
			      
		ProcessBuilder pb = new ProcessBuilder(command); 
		Process process = pb.start(); 
			  
		BufferedReader stdInput = new BufferedReader(new InputStreamReader(process.getInputStream()));
		BufferedReader stdError = new BufferedReader(new InputStreamReader(process.getErrorStream())); 
			  
		LOGGER.debug("Here is the standard output of the command:\n"); 
		while ((s = stdInput.readLine()) != null) 
		{ 
			LOGGER.debug(s);
		} 
			  
		LOGGER.debug("Here is the standard error of the command (if any):\n"); 
		while ((s = stdError.readLine()) != null) 
		{ 
			LOGGER.debug(s);
		} 
		return process.waitFor();
	} 
			    

	/**
	 * Method sendRsyncCommand.
	 *
	 * @param transId the trans id
	 * @param fileName the file name
	 */
	public void sendRsyncCommand(String transId, String fileName) 
	{
		String aaiServerList = null;
		String rsyncOptionsList = null;
		
		try {
			aaiServerList = AAIConfig.get(DEFAULT_CHECK + "serverlist");
			rsyncOptionsList = AAIConfig.get("aai.rsync.options.list");
			String enableRsync = AAIConfig.get("aai.rsync.enabled");
			
			if (!AAIConfig.isEmpty(enableRsync) && "n".equalsIgnoreCase(enableRsync)){
	    		LOGGER.info("rsync not invoked for " + fileName + ": rsync is not enabled in aaiconfig.properties");
				return;
			}
		} catch ( Exception e ) {
    		LOGGER.warn( "rsync not invoked: missing aaiconfig.properties entries for rsync" );
		}
		
		LOGGER.info("rsync to copy files started....");
		
    	ArrayList<String> remoteHostList = new ArrayList<String>();
    	StringTokenizer serverList = new StringTokenizer( aaiServerList, "|" );
    	String host = null;
		try {
			host = getHost();
			String remoteConnString = null;
			 
			remoteHostList = getRemoteHostList(serverList, host);
			LOGGER.debug("This host:" + host);
	    	String pickUpDirectory = AAIConfig.get("instar.pickup.dir");
	    	String user = AAIConfig.get("aai.rsync.remote.user"); 
	    	String rsyncCmd = AAIConfig.get("aai.rsync.command");
	    	
	    	//Push: rsync [OPTION...] SRC... [USER@]HOST:DEST
	    	
	    	java.util.Iterator<String> remoteHostItr = remoteHostList.iterator();
	    	while (!remoteHostList.isEmpty() && remoteHostItr.hasNext()) {
	    		String remoteHost = remoteHostItr.next();
	    		remoteConnString =user+"@"+remoteHost+":"+pickUpDirectory;
				   
				List<String> commands = new ArrayList<String>(); 
			    commands.add(rsyncCmd); 
			    StringTokenizer optionTks = new StringTokenizer( rsyncOptionsList, "|" );
			    while (optionTks.hasMoreTokens()){
			    	commands.add(optionTks.nextToken());
			    }
			    commands.add(fileName); // src directory/fileName
			    commands.add(remoteConnString); // target username/host/path
			    LOGGER.debug("Commands: " + commands.toString());
			    int rsyncResult = doCommand(commands);
			    if ( rsyncResult == 0 ) {
			    	LOGGER.info("rsync completed for "+remoteHost);
			    }else {
					LOGGER.error("rsync failed for "+ remoteHost+ " with response code "+rsyncResult );
				}
			} 
    	} catch ( Exception e) {
    		LOGGER.error("no server found processing serverList for host " + host + ": " + e.getMessage() + " (AAI_4000)");
		}
	}

	/**
	 * Gets the remote host list.
	 *
	 * @param serverList the server list
	 * @param host the host
	 * @return the remote host list
	 */
	private ArrayList<String> getRemoteHostList(StringTokenizer serverList, String host) {
		ArrayList<String> remoteHostList = new ArrayList<String>();
		String remoteHost = null;
		while ( serverList.hasMoreTokens() ) {
    		remoteHost = serverList.nextToken();
    		if (!host.equalsIgnoreCase(remoteHost)){
    			remoteHostList.add(remoteHost);
    		}
		}
		return remoteHostList;
	}

	/**
	 * Gets the host.
	 *
	 * @return the host
	 * @throws AAIException the AAI exception
	 */
	private String getHost() throws AAIException {
		String aaiServerList = AAIConfig.get(DEFAULT_CHECK + "serverlist");
		String hostname = null;
		try {
			InetAddress ip = InetAddress.getLocalHost();
        	if ( ip != null ) {
        		hostname = ip.getHostName();
        		if ( hostname != null ) {
        			if  ( !( aaiServerList.contains(hostname) ) )
        				LOGGER.warn("Host name not found in server list " + hostname);
        		} else
        			LOGGER.warn("InetAddress returned null hostname");
        	} 
        	 
		} catch (UnknownHostException e) {
			LOGGER.warn("InetAddress getLocalHost exception " + e.getMessage());
    	}
    	
		return hostname;
	}
	
}