/*
 * Copyright 2015-present Open Networking Laboratory
 *
 * 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.opencord.cordvtn.api;

import com.fasterxml.jackson.databind.JsonNode;
import com.google.common.base.Strings;
import com.google.common.collect.Maps;
import com.google.common.collect.Sets;
import org.onlab.packet.IpAddress;
import org.onlab.packet.MacAddress;
import org.onlab.packet.TpPort;
import org.onosproject.core.ApplicationId;
import org.onosproject.net.config.Config;
import org.onosproject.xosclient.api.OpenStackAccess;
import org.onosproject.xosclient.api.XosAccess;
import org.slf4j.Logger;

import java.util.Map;
import java.util.Set;

import static org.slf4j.LoggerFactory.getLogger;

/**
 * Configuration object for CordVtn service.
 */
public class CordVtnConfig extends Config<ApplicationId> {

    protected final Logger log = getLogger(getClass());

    private static final String PRIVATE_GATEWAY_MAC = "privateGatewayMac";
    private static final String PUBLIC_GATEWAYS = "publicGateways";
    private static final String GATEWAY_IP = "gatewayIp";
    private static final String GATEWAY_MAC = "gatewayMac";
    private static final String LOCAL_MANAGEMENT_IP = "localManagementIp";
    private static final String OVSDB_PORT = "ovsdbPort";

    private static final String CORDVTN_NODES = "nodes";
    private static final String HOSTNAME = "hostname";
    private static final String HOST_MANAGEMENT_IP = "hostManagementIp";
    private static final String HOST_MANAGEMENT_IFACE = "hostManagementIface";
    private static final String DATA_IP = "dataPlaneIp";
    private static final String DATA_IFACE = "dataPlaneIntf";
    private static final String INTEGRATION_BRIDGE_ID = "bridgeId";

    private static final String SSH = "ssh";
    private static final String SSH_PORT = "sshPort";
    private static final String SSH_USER = "sshUser";
    private static final String SSH_KEY_FILE = "sshKeyFile";

    private static final String OPENSTACK = "openstack";
    private static final String XOS = "xos";

    private static final String ENDPOINT = "endpoint";
    private static final String TENANT = "tenant";
    private static final String USER = "user";
    private static final String PASSWORD = "password";

    // TODO implement isValid

    /**
     * Returns the set of nodes read from network config.
     *
     * @return set of CordVtnNodeConfig or empty set
     */
    public Set<CordVtnNode> cordVtnNodes() {

        Set<CordVtnNode> nodes = Sets.newHashSet();

        // TODO implement isValid and move these blocks to it
        JsonNode cordvtnNodes = object.get(CORDVTN_NODES);
        if (cordvtnNodes == null) {
            log.debug("No CORD VTN nodes found");
            return nodes;
        }

        JsonNode sshNode = object.get(SSH);
        if (sshNode == null) {
            log.warn("SSH information not found");
            return nodes;
        }

        for (JsonNode cordvtnNode : cordvtnNodes) {
            // TODO implement isValid and move this block to it
            NetworkAddress hostMgmt = NetworkAddress.valueOf(getConfig(cordvtnNode, HOST_MANAGEMENT_IP));
            NetworkAddress localMgmt = NetworkAddress.valueOf(getConfig(object, LOCAL_MANAGEMENT_IP));
            if (hostMgmt.prefix().contains(localMgmt.prefix()) ||
                    localMgmt.prefix().contains(hostMgmt.prefix())) {
                log.error("hostMamt and localMgmt cannot be overlapped, skip this node");
                continue;
            }

            String hostname = getConfig(cordvtnNode, HOSTNAME);
            SshAccessInfo sshInfo = new SshAccessInfo(
                    hostMgmt.ip().getIp4Address(),
                    TpPort.tpPort(Integer.parseInt(getConfig(sshNode, SSH_PORT))),
                    getConfig(sshNode, SSH_USER), getConfig(sshNode, SSH_KEY_FILE));

            CordVtnNode.Builder nodeBuilder = CordVtnNode.builder()
                    .hostname(hostname)
                    .hostMgmtIp(hostMgmt)
                    .localMgmtIp(localMgmt)
                    .dataIp(getConfig(cordvtnNode, DATA_IP))
                    .sshInfo(sshInfo)
                    .integrationBridgeId(getConfig(cordvtnNode, INTEGRATION_BRIDGE_ID))
                    .dataIface(getConfig(cordvtnNode, DATA_IFACE));

            String ovsdbPort = getConfig(object, OVSDB_PORT);
            if (!Strings.isNullOrEmpty(ovsdbPort)) {
                nodeBuilder.ovsdbPort(Integer.parseInt(ovsdbPort));
            }

            String hostMgmtIface = getConfig(cordvtnNode, HOST_MANAGEMENT_IFACE);
            if (!Strings.isNullOrEmpty(hostMgmtIface)) {
                nodeBuilder.hostMgmtIface(hostMgmtIface);
            }

            nodes.add(nodeBuilder.build());
        }
        return nodes;
    }

    /**
     * Returns value of a given path. If the path is missing, show log and return
     * null.
     *
     * @param path path
     * @return value or null
     */
    private String getConfig(JsonNode jsonNode, String path) {
        jsonNode = jsonNode.path(path);

        if (jsonNode.isMissingNode()) {
            log.debug("{} is not configured", path);
            return null;
        } else {
            return jsonNode.asText();
        }
    }

    /**
     * Returns private network gateway MAC address.
     *
     * @return mac address, or null
     */
    public MacAddress privateGatewayMac() {
        JsonNode jsonNode = object.get(PRIVATE_GATEWAY_MAC);
        if (jsonNode == null) {
            return null;
        }

        try {
            return MacAddress.valueOf(jsonNode.asText());
        } catch (IllegalArgumentException e) {
            log.error("Wrong MAC address format {}", jsonNode.asText());
            return null;
        }
    }

    /**
     * Returns public network gateway IP and MAC address pairs.
     *
     * @return map of ip and mac address
     */
    public Map<IpAddress, MacAddress> publicGateways() {
        JsonNode jsonNodes = object.get(PUBLIC_GATEWAYS);
        if (jsonNodes == null) {
            return Maps.newHashMap();
        }

        Map<IpAddress, MacAddress> publicGateways = Maps.newHashMap();
        jsonNodes.forEach(jsonNode -> {
            try {
                publicGateways.put(
                        IpAddress.valueOf(jsonNode.path(GATEWAY_IP).asText()),
                        MacAddress.valueOf(jsonNode.path(GATEWAY_MAC).asText()));
            } catch (IllegalArgumentException | NullPointerException e) {
                log.error("Wrong address format {}", e.toString());
            }
        });

        return publicGateways;
    }

    /**
     * Returns XOS access information.
     *
     * @return XOS access, or null
     */
    public XosAccess xosAccess() {
        JsonNode jsonNode = object.get(XOS);
        if (jsonNode == null) {
            return null;
        }

        try {
            return new XosAccess(getConfig(jsonNode, ENDPOINT),
                                 getConfig(jsonNode, USER),
                                 getConfig(jsonNode, PASSWORD));
        } catch (NullPointerException e) {
            log.error("Failed to get XOS access");
            return null;
        }
    }

    /**
     * Returns OpenStack API access information.
     *
     * @return openstack access
     */
    public OpenStackAccess openstackAccess() {
        JsonNode jsonNode = object.get(OPENSTACK);
        if (jsonNode == null) {
            log.error("Failed to get OpenStack configurations");
            return null;
        }

        try {
            return new OpenStackAccess(
                    jsonNode.path(ENDPOINT).asText(),
                    jsonNode.path(TENANT).asText(),
                    jsonNode.path(USER).asText(),
                    jsonNode.path(PASSWORD).asText());
        } catch (IllegalArgumentException | NullPointerException e) {
            log.error("Failed to get OpenStack configurations");
            return null;
        }
    }
}