/*
 * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
 * and is available at http://www.eclipse.org/legal/epl-v10.html
 */
package org.opendaylight.protocol.pcep.impl;

import java.util.HashMap;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import org.opendaylight.protocol.framework.DeserializerException;
import org.opendaylight.protocol.framework.DocumentedException;
import org.opendaylight.protocol.framework.ProtocolMessage;
import org.opendaylight.protocol.framework.ProtocolMessageFactory;
import org.opendaylight.protocol.framework.ProtocolMessageHeader;
import org.opendaylight.protocol.util.ByteArray;
import org.opendaylight.protocol.pcep.PCEPDeserializerException;
import org.opendaylight.protocol.pcep.PCEPDocumentedException;
import org.opendaylight.protocol.pcep.PCEPErrors;
import org.opendaylight.protocol.pcep.PCEPMessage;
import org.opendaylight.protocol.pcep.impl.message.PCCreateMessageParser;
import org.opendaylight.protocol.pcep.impl.message.PCEPCloseMessageParser;
import org.opendaylight.protocol.pcep.impl.message.PCEPErrorMessageParser;
import org.opendaylight.protocol.pcep.impl.message.PCEPKeepAliveMessageParser;
import org.opendaylight.protocol.pcep.impl.message.PCEPNotificationMessageParser;
import org.opendaylight.protocol.pcep.impl.message.PCEPOpenMessageParser;
import org.opendaylight.protocol.pcep.impl.message.PCEPRawMessage;
import org.opendaylight.protocol.pcep.impl.message.PCEPReplyMessageParser;
import org.opendaylight.protocol.pcep.impl.message.PCEPReportMessageParser;
import org.opendaylight.protocol.pcep.impl.message.PCEPRequestMessageParser;
import org.opendaylight.protocol.pcep.impl.message.PCEPUpdateRequestMessageParser;
import org.opendaylight.protocol.pcep.impl.message.PCEPXRAddTunnelMessageParser;
import org.opendaylight.protocol.pcep.impl.message.PCEPXRDeleteTunnelMessageParser;
import org.opendaylight.protocol.pcep.message.PCCreateMessage;
import org.opendaylight.protocol.pcep.message.PCEPCloseMessage;
import org.opendaylight.protocol.pcep.message.PCEPErrorMessage;
import org.opendaylight.protocol.pcep.message.PCEPKeepAliveMessage;
import org.opendaylight.protocol.pcep.message.PCEPNotificationMessage;
import org.opendaylight.protocol.pcep.message.PCEPOpenMessage;
import org.opendaylight.protocol.pcep.message.PCEPReplyMessage;
import org.opendaylight.protocol.pcep.message.PCEPReportMessage;
import org.opendaylight.protocol.pcep.message.PCEPRequestMessage;
import org.opendaylight.protocol.pcep.message.PCEPUpdateRequestMessage;
import org.opendaylight.protocol.pcep.message.PCEPXRAddTunnelMessage;
import org.opendaylight.protocol.pcep.message.PCEPXRDeleteTunnelMessage;

/**
 * Factory for subclasses of {@link org.opendaylight.protocol.pcep.PCEPMessage PCEPMessage}
 */
public class PCEPMessageFactory implements ProtocolMessageFactory {

    private final static Logger logger = LoggerFactory.getLogger(PCEPMessageFactory.class);

    /**
     * Type identifier for {@link org.opendaylight.protocol.pcep.PCEPMessage PCEPMessage}
     */
    public enum PCEPMessageType {
		OPEN(1), NOTIFICATION(5), KEEPALIVE(2), RESPONSE(4), REQUEST(3), ERROR(6), CLOSE(7), UPDATE_REQUEST(11), STATUS_REPORT(10),
		// TODO: replace with actual values by IANA
		XR_ADD_TUNNEL(8),
		XR_DELETE_TUNNEL(9),
		PCCREATE(12);

		private final int identifier;

		PCEPMessageType(final int identifier) {
		    this.identifier = identifier;
		}

		public int getIdentifier() {
		    return this.identifier;
		}

		public static PCEPMessageType getFromInt(final int type) throws PCEPDeserializerException {

		    for (final PCEPMessageType type_e : PCEPMessageType.values()) {
			if (type_e.getIdentifier() == type)
			    return type_e;
		    }

		    throw new PCEPDeserializerException("Unknown PCEPMessage Class identifier. Passed: " + type + "; Known: " + PCEPMessageType.values() + ".");
		}
	}

    private static class MapOfParsers extends HashMap<PCEPMessageType, PCEPMessageParser> {

	private static final long serialVersionUID = -5715193806554448822L;

	private final static MapOfParsers instance = new MapOfParsers();

	private MapOfParsers() {
	    this.fillInMap();
	}

	private void fillInMap() {
	    this.put(PCEPMessageType.OPEN, new PCEPOpenMessageParser());
	    this.put(PCEPMessageType.KEEPALIVE, new PCEPKeepAliveMessageParser());
	    this.put(PCEPMessageType.NOTIFICATION, new PCEPNotificationMessageParser());
	    this.put(PCEPMessageType.ERROR, new PCEPErrorMessageParser());
	    this.put(PCEPMessageType.RESPONSE, new PCEPReplyMessageParser());
	    this.put(PCEPMessageType.REQUEST, new PCEPRequestMessageParser());
	    this.put(PCEPMessageType.UPDATE_REQUEST, new PCEPUpdateRequestMessageParser());
	    this.put(PCEPMessageType.STATUS_REPORT, new PCEPReportMessageParser());
	    this.put(PCEPMessageType.CLOSE, new PCEPCloseMessageParser());
	    this.put(PCEPMessageType.XR_ADD_TUNNEL, new PCEPXRAddTunnelMessageParser());
	    this.put(PCEPMessageType.XR_DELETE_TUNNEL, new PCEPXRDeleteTunnelMessageParser());
	    this.put(PCEPMessageType.PCCREATE, new PCCreateMessageParser());
	}

	public static MapOfParsers getInstance() {
	    return instance;
		}
    }

    /**
     *
     * @param bytes
     *            assume array of bytes without common header
     * @param msgHeader
     * @return Parsed specific PCEPMessage
     * @throws PCEPDeserializerException
     * @throws PCEPDocumentedException
     */

    @Override
	public ProtocolMessage parse(final byte[] bytes, final ProtocolMessageHeader msgH) throws DeserializerException, DocumentedException {
    	final PCEPMessageHeader msgHeader = (PCEPMessageHeader) msgH;
		if (bytes == null)
		    throw new IllegalArgumentException("Array of bytes is mandatory.");
		if (msgHeader == null)
		    throw new IllegalArgumentException("PCEPMessageHeader is mandatory.");

		logger.trace("Attempt to parse message from bytes: {}", ByteArray.bytesToHexString(bytes));

		if (bytes.length != (msgHeader.getLength() - PCEPMessageHeader.COMMON_HEADER_LENGTH))
		    throw new DeserializerException("Size don't match size specified in header. Passed: " + bytes.length + "; Expected: "
			    + (msgHeader.getLength() - PCEPMessageHeader.COMMON_HEADER_LENGTH) + ". " + msgHeader.getLength());

		/*
		 * if PCEPObjectIdentifier.getObjectClassFromInt() dont't throws
		 * exception and if returned null we know the error type
		 */
		PCEPMessageType msgType;
		try {
			msgType = PCEPMessageType.getFromInt(msgHeader.getType());
		} catch (final PCEPDeserializerException e) {
			throw new DeserializerException(e.getMessage(), e);
		}
		if (msgType == null)
		    throw new DocumentedException("Unhandled message type " + msgHeader.getType(), new PCEPDocumentedException("Unhandled message type " + msgHeader.getType(), PCEPErrors.CAPABILITY_NOT_SUPPORTED));

		PCEPMessage msg;
		try {
			msg = new PCEPRawMessage(PCEPObjectFactory.parseObjects(bytes), msgType);
		} catch (final PCEPDeserializerException e) {
			throw new DeserializerException(e.getMessage(), e);
		} catch (final PCEPDocumentedException e) {
			throw new DocumentedException(e.getMessage(), e);
		}
		logger.debug("Message was parsed. {}", msg);
		return msg;
    }

    @Override
	public byte[] put(final ProtocolMessage msg) {
    	final PCEPMessage pcepMsg = (PCEPMessage) msg;
		if (pcepMsg == null)
		    throw new IllegalArgumentException("PCEPMessage is mandatory.");

		final PCEPMessageType msgType;

		if (pcepMsg instanceof PCEPOpenMessage) {
		    msgType = PCEPMessageType.OPEN;
		} else if (pcepMsg instanceof PCEPKeepAliveMessage) {
		    msgType = PCEPMessageType.KEEPALIVE;
		} else if (pcepMsg instanceof PCEPCloseMessage) {
		    msgType = PCEPMessageType.CLOSE;
		} else if (pcepMsg instanceof PCEPReplyMessage) {
		    msgType = PCEPMessageType.RESPONSE;
		} else if (pcepMsg instanceof PCEPRequestMessage) {
		    msgType = PCEPMessageType.REQUEST;
		} else if (pcepMsg instanceof PCEPNotificationMessage) {
		    msgType = PCEPMessageType.NOTIFICATION;
		} else if (pcepMsg instanceof PCEPErrorMessage) {
		    msgType = PCEPMessageType.ERROR;
		} else if (pcepMsg instanceof PCEPReportMessage) {
		    msgType = PCEPMessageType.STATUS_REPORT;
		} else if (pcepMsg instanceof PCEPUpdateRequestMessage) {
		    msgType = PCEPMessageType.UPDATE_REQUEST;
		} else if (pcepMsg instanceof PCEPXRAddTunnelMessage) {
		    msgType = PCEPMessageType.XR_ADD_TUNNEL;
		} else if (pcepMsg instanceof PCEPXRDeleteTunnelMessage) {
		    msgType = PCEPMessageType.XR_DELETE_TUNNEL;
		} else if (pcepMsg instanceof PCCreateMessage) {
		    msgType = PCEPMessageType.PCCREATE;
		} else {
		    logger.error("Unknown instance of PCEPMessage. Message class: {}", pcepMsg.getClass());
		    throw new IllegalArgumentException("Unknown instance of PCEPMessage. Passed " + pcepMsg.getClass());
		}

		logger.trace("Serializing {}", msgType);

		final byte[] msgBody = MapOfParsers.getInstance().get(msgType).put(pcepMsg);

		final PCEPMessageHeader msgHeader = new PCEPMessageHeader(msgType.getIdentifier(), msgBody.length + PCEPMessageHeader.COMMON_HEADER_LENGTH,
				PCEPMessage.PCEP_VERSION);

		final byte[] headerBytes = msgHeader.toBytes();
		final byte[] retBytes = new byte[headerBytes.length + msgBody.length];

		ByteArray.copyWhole(headerBytes, retBytes, 0);
		ByteArray.copyWhole(msgBody, retBytes, PCEPMessageHeader.COMMON_HEADER_LENGTH);

		return retBytes;
    }
}