/*
 * 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.ietf.initiated00;

import io.netty.buffer.ByteBuf;

import java.util.List;

import org.opendaylight.protocol.pcep.spi.AbstractMessageParser;
import org.opendaylight.protocol.pcep.spi.ObjectHandlerRegistry;
import org.opendaylight.protocol.pcep.spi.PCEPDeserializerException;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.crabbe.initiated.rev131126.Pcinitiate;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.crabbe.initiated.rev131126.PcinitiateBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.crabbe.initiated.rev131126.PcinitiateMessage;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.crabbe.initiated.rev131126.pcinitiate.message.PcinitiateMessageBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.crabbe.initiated.rev131126.pcinitiate.message.pcinitiate.message.Requests;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.crabbe.initiated.rev131126.pcinitiate.message.pcinitiate.message.RequestsBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.ietf.stateful.rev131222.lsp.object.Lsp;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.ietf.stateful.rev131222.srp.object.Srp;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.Message;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.Object;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.bandwidth.object.Bandwidth;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.endpoints.object.EndpointsObj;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.explicit.route.object.Ero;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.include.route.object.Iro;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.lsp.attributes.Metrics;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.lsp.attributes.MetricsBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.lspa.object.Lspa;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev131005.metric.object.Metric;

import com.google.common.collect.Lists;

/**
 * Parser for {@link Pcinitiate}
 */
public class PcinitiateMessageParser extends AbstractMessageParser {

	public static final int TYPE = 12;

	public PcinitiateMessageParser(final ObjectHandlerRegistry registry) {
		super(registry);
	}

	@Override
	public void serializeMessage(final Message message, final ByteBuf buffer) {
		if (!(message instanceof PcinitiateMessage)) {
			throw new IllegalArgumentException("Wrong instance of Message. Passed instance of " + message.getClass()
					+ ". Needed PcinitiateMessage.");
		}
		final org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.crabbe.initiated.rev131126.pcinitiate.message.PcinitiateMessage init = ((Pcinitiate) message).getPcinitiateMessage();
		for (final Requests req : init.getRequests()) {
			buffer.writeBytes(serializeObject(req.getSrp()));
			buffer.writeBytes(serializeObject(req.getLsp()));
			if (req.getEndpointsObj() != null) {
				buffer.writeBytes(serializeObject(req.getEndpointsObj()));
			}
			if (req.getEro() != null) {
				buffer.writeBytes(serializeObject(req.getEro()));
			}
			if (req.getLspa() != null) {
				buffer.writeBytes(serializeObject(req.getLspa()));
			}
			if (req.getBandwidth() != null) {
				buffer.writeBytes(serializeObject(req.getBandwidth()));
			}
			if (req.getMetrics() != null && !req.getMetrics().isEmpty()) {
				for (final Metrics m : req.getMetrics()) {
					buffer.writeBytes(serializeObject(m.getMetric()));
				}
			}
			if (req.getIro() != null) {
				buffer.writeBytes(serializeObject(req.getIro()));
			}
		}
	}

	@Override
	protected Message validate(final List<Object> objects, final List<Message> errors) throws PCEPDeserializerException {
		if (objects == null) {
			throw new IllegalArgumentException("Passed list can't be null.");
		}
		final PcinitiateMessageBuilder builder = new PcinitiateMessageBuilder();
		final List<Requests> reqs = Lists.newArrayList();
		Requests req = null;
		while (!objects.isEmpty()) {
			req = this.getValidRequest(objects);
			if (req == null) {
				break;
			}
			reqs.add(req);
		}
		builder.setRequests(reqs);
		return new PcinitiateBuilder().setPcinitiateMessage(builder.build()).build();
	}

	private Requests getValidRequest(final List<Object> objects) {
		final RequestsBuilder builder = new RequestsBuilder();
		builder.setSrp((Srp) objects.get(0));
		objects.remove(0);

		builder.setLsp((Lsp) objects.get(0));
		objects.remove(0);

		final List<Metrics> metrics = Lists.newArrayList();

		Object obj;
		State state = State.Init;
		while (!objects.isEmpty() && !state.equals(State.End)) {
			obj = objects.get(0);

			switch (state) {
			case Init:
				state = State.EndpointsIn;
				if (obj instanceof EndpointsObj) {
					builder.setEndpointsObj((EndpointsObj) obj);
					break;
				}
			case EndpointsIn:
				state = State.EroIn;
				if (obj instanceof Ero) {
					builder.setEro((Ero) obj);
					break;
				}
			case EroIn:
				state = State.LspaIn;
				if (obj instanceof Lspa) {
					builder.setLspa((Lspa) obj);
					break;
				}
			case LspaIn:
				state = State.BandwidthIn;
				if (obj instanceof Bandwidth) {
					builder.setBandwidth((Bandwidth) obj);
					break;
				}
			case BandwidthIn:
				state = State.MetricIn;
				if (obj instanceof Metric) {
					metrics.add(new MetricsBuilder().setMetric((Metric) obj).build());
					state = State.BandwidthIn;
					break;
				}
			case MetricIn:
				state = State.IroIn;
				if (obj instanceof Iro) {
					builder.setIro((Iro) obj);
					break;
				}
			case IroIn:
				state = State.End;
				break;
			case End:
				break;
			}
			if (!state.equals(State.End)) {
				objects.remove(0);
			}
		}
		builder.setMetrics(metrics);
		return builder.build();
	}

	private enum State {
		Init, EndpointsIn, EroIn, LspaIn, BandwidthIn, MetricIn, IroIn, End
	}

	@Override
	public int getMessageType() {
		return TYPE;
	}
}