/*******************************************************************************
 * Copyright (c) 2013 GigaSpaces Technologies Ltd. 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.
 *******************************************************************************/
package org.cloudifysource.shell.validators;

import java.io.IOException;
import java.net.UnknownHostException;
import java.util.logging.Level;
import java.util.logging.Logger;

import org.apache.commons.lang.StringUtils;
import org.cloudifysource.dsl.internal.CloudifyConstants;
import org.cloudifysource.dsl.internal.CloudifyErrorMessages;
import org.cloudifysource.dsl.utils.IOUtils;
import org.cloudifysource.dsl.utils.IPUtils;
import org.cloudifysource.shell.exceptions.CLIValidationException;

/**
 * This class validates a connection to the lookup service can be established on the specified port.
 * @author noak
 * @since 2.7.0
 */
public class LusConnectionValidator implements CloudifyAgentValidator {
	
	private static final long TEN_SECONDS_MILLI = 10000;
	private final Logger logger = Logger.getLogger(this.getClass().getName());
	private static final int MAX_NUM_RETRIES = 3;
	private String lusIpAddresses;
	
	// TODO noa run only on agent
	// use lookup locators
	
	
	/**
	 * Setter for lusIpAddress.
	 * @param lusIpAddress The LUS IP address to validate, or null to use the env var setting.
	 */
	public void setLusIpAddress(final String lusIpAddresses) {
		this.lusIpAddresses = lusIpAddresses;
	}

	/**
	 * Validates a connection can be established to the lookup service on the specified port.
	 * @throws CLIValidationException Indicates a failure to establish a connection.
	 */
	@Override
	public void validate() throws CLIValidationException {

		// get lus IP address from the environment variable if not already set
		if (StringUtils.isBlank(lusIpAddresses)) {
			lusIpAddresses = System.getenv(CloudifyConstants.LUS_IP_ADDRESS_ENV);
		}
		
		String[] lusAddresses = lusIpAddresses.split(",");
		Exception ex = new Exception();
		for (String address : lusAddresses) {
			try {
				validateManagementAddress(address);
				return;
			} catch (final CLIValidationException e) {
				ex = e;
			}
		}
		throw (CLIValidationException) ex;
	}

	void validateManagementAddress(final String address)
			throws CLIValidationException {
		// TODO noak : throw CLIValidationException with custom exit code (130) instead?
		if (StringUtils.isBlank(address)) {
			throw new IllegalArgumentException("LUS IP address not configred. The environment variable \"" 
					+ CloudifyConstants.LUS_IP_ADDRESS_ENV + "\" is not set.");
		}
		
		//parse the ip address and port
		final String hostAddress = IPUtils.getHostFromFullAddress(address);
		final int port = IPUtils.getPortFromFullAddress(address);		
		for (int i = 0; i < MAX_NUM_RETRIES; i++) {
			try {
				validateConnection(hostAddress, port);
				return;
			} catch (CLIValidationException e) {
				if (i == 2) {
					throw e;
				}
				logger.log(Level.WARNING, "Failed validating connection to lus. " 
						+ "Error was: " + e.getMessage()
							+ "Attempting to reconnect.", e);
			}
			IOUtils.threadSleep(TEN_SECONDS_MILLI);
		}
	}

	void validateConnection(final String hostAddress, final int port)
			throws CLIValidationException {
		try {
			IPUtils.validateConnection(hostAddress, port);
			return;
		} catch (UnknownHostException uhe) {
			// thrown if the IP address of the host could not be determined.
			throw new CLIValidationException(uhe, 127,
					CloudifyErrorMessages.LUS_CONNECTION_VALIDATION_ABORTED_UNKNOWN_HOST.getName(), hostAddress);
		} catch (IOException ioe) {
			// thrown if an I/O error occurs when creating the socket or connecting.
			throw new CLIValidationException(ioe, 128,
					CloudifyErrorMessages.LUS_CONNECTION_VALIDATION_ABORTED_IO_ERROR.getName(), hostAddress, port,
					ioe.getMessage());
		} catch (SecurityException se) {
			// thrown if a security manager exists and permission to resolve the host name is denied.
			throw new CLIValidationException(se,  129,
					CloudifyErrorMessages.LUS_CONNECTION_VALIDATION_ABORTED_NO_PERMISSION.getName(), hostAddress,
					port, se.getMessage());
		}
	}
}