/*
 * Copyright (c) 2016 Brocade Communication Systems 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.netconf.callhome.mount;

import io.netty.util.concurrent.EventExecutor;
import io.netty.util.concurrent.FailedFuture;
import io.netty.util.concurrent.Future;
import java.net.InetSocketAddress;
import org.opendaylight.aaa.encrypt.AAAEncryptionService;
import org.opendaylight.controller.config.threadpool.ScheduledThreadPool;
import org.opendaylight.controller.config.threadpool.ThreadPool;
import org.opendaylight.controller.md.sal.binding.api.DataBroker;
import org.opendaylight.controller.md.sal.dom.api.DOMMountPointService;
import org.opendaylight.netconf.callhome.mount.CallHomeMountSessionContext.CloseCallback;
import org.opendaylight.netconf.callhome.protocol.CallHomeChannelActivator;
import org.opendaylight.netconf.callhome.protocol.CallHomeNetconfSubsystemListener;
import org.opendaylight.netconf.callhome.protocol.CallHomeProtocolSessionContext;
import org.opendaylight.netconf.client.NetconfClientDispatcher;
import org.opendaylight.netconf.client.NetconfClientSession;
import org.opendaylight.netconf.client.conf.NetconfClientConfiguration;
import org.opendaylight.netconf.client.conf.NetconfReconnectingClientConfiguration;
import org.opendaylight.netconf.topology.api.SchemaRepositoryProvider;
import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.NodeId;
import org.opendaylight.yang.gen.v1.urn.tbd.params.xml.ns.yang.network.topology.rev131021.network.topology.topology.Node;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class CallHomeMountDispatcher implements NetconfClientDispatcher, CallHomeNetconfSubsystemListener {

    private static final Logger LOG = LoggerFactory.getLogger(CallHomeMountDispatcher.class);

    private final String topologyId;
    private final EventExecutor eventExecutor;
    private final ScheduledThreadPool keepaliveExecutor;
    private final ThreadPool processingExecutor;
    private final SchemaRepositoryProvider schemaRepositoryProvider;
    private final CallHomeMountSessionManager sessionManager;
    private final DataBroker dataBroker;
    private final DOMMountPointService mountService;
    private final AAAEncryptionService encryptionService;

    protected CallHomeTopology topology;

    private final CloseCallback onCloseHandler = new CloseCallback() {
        @Override
        public void onClosed(final CallHomeMountSessionContext deviceContext) {
            LOG.info("Removing {} from Netconf Topology.", deviceContext.getId());
            topology.disconnectNode(deviceContext.getId());
        }
    };

    public CallHomeMountDispatcher(final String topologyId, final EventExecutor eventExecutor,
                                   final ScheduledThreadPool keepaliveExecutor, final ThreadPool processingExecutor,
                                   final SchemaRepositoryProvider schemaRepositoryProvider, final DataBroker dataBroker,
                                   final DOMMountPointService mountService,
                                   final AAAEncryptionService encryptionService) {
        this.topologyId = topologyId;
        this.eventExecutor = eventExecutor;
        this.keepaliveExecutor = keepaliveExecutor;
        this.processingExecutor = processingExecutor;
        this.schemaRepositoryProvider = schemaRepositoryProvider;
        this.sessionManager = new CallHomeMountSessionManager();
        this.dataBroker = dataBroker;
        this.mountService = mountService;
        this.encryptionService = encryptionService;
    }

    @Override
    public Future<NetconfClientSession> createClient(final NetconfClientConfiguration clientConfiguration) {
        return activateChannel(clientConfiguration);
    }

    @Override
    public Future<Void> createReconnectingClient(final NetconfReconnectingClientConfiguration clientConfiguration) {
        return activateChannel(clientConfiguration);
    }

    private <V> Future<V> activateChannel(final NetconfClientConfiguration conf) {
        final InetSocketAddress remoteAddr = conf.getAddress();
        final CallHomeMountSessionContext context = getSessionManager().getByAddress(remoteAddr);
        LOG.info("Activating NETCONF channel for ip {} device context {}", remoteAddr, context);
        if (context == null) {
            return new FailedFuture<>(eventExecutor, new NullPointerException());
        }
        return context.activateNetconfChannel(conf.getSessionListener());
    }

    void createTopology() {
        this.topology = new CallHomeTopology(topologyId, this, eventExecutor, keepaliveExecutor, processingExecutor,
                schemaRepositoryProvider, dataBroker, mountService, encryptionService);
    }

    @Override
    public void onNetconfSubsystemOpened(final CallHomeProtocolSessionContext session,
                                         final CallHomeChannelActivator activator) {
        final CallHomeMountSessionContext deviceContext =
                getSessionManager().createSession(session, activator, onCloseHandler);
        final NodeId nodeId = deviceContext.getId();
        final Node configNode = deviceContext.getConfigNode();
        LOG.info("Provisioning fake config {}", configNode);
        topology.connectNode(nodeId, configNode);
    }

    public CallHomeMountSessionManager getSessionManager() {
        return sessionManager;
    }
}