// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you 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 com.cloud.network;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;

import org.apache.log4j.Logger;

import com.cloud.utils.Pair;

import com.cloud.agent.api.routing.LoadBalancerConfigCommand;
import com.cloud.agent.api.to.LoadBalancerTO;
import com.cloud.agent.api.to.PortForwardingRuleTO;
import com.cloud.agent.api.to.LoadBalancerTO.DestinationTO;
import com.cloud.agent.api.to.LoadBalancerTO.StickinessPolicyTO;
import com.cloud.network.rules.LbStickinessMethod.StickinessMethodType;
import com.cloud.utils.net.NetUtils;


public class HAProxyConfigurator implements LoadBalancerConfigurator {

    private static final Logger s_logger = Logger.getLogger(HAProxyConfigurator.class);
    private static final String blankLine = "\t ";
    private static String[] globalSection = { "global",
            "\tlog 127.0.0.1:3914   local0 warning", 
            "\tmaxconn 4096",
            "\tchroot /var/lib/haproxy", 
            "\tuser haproxy",
            "\tgroup haproxy",
            "\tdaemon" };

    private static String[] defaultsSection = { "defaults", 
            "\tlog     global",
            "\tmode    tcp", 
            "\toption  dontlognull", 
            "\tretries 3",
            "\toption redispatch", 
            "\toption forwardfor",
            "\toption forceclose", 
            "\ttimeout connect    5000",
            "\ttimeout client     50000", 
            "\ttimeout server     50000" };

    private static String[] defaultListen = { "listen  vmops 0.0.0.0:9",
            "\toption transparent" };

    @Override
    public String[] generateConfiguration(List<PortForwardingRuleTO> fwRules) {
        // Group the rules by publicip:publicport
        Map<String, List<PortForwardingRuleTO>> pools = new HashMap<String, List<PortForwardingRuleTO>>();

        for (PortForwardingRuleTO rule : fwRules) {
            StringBuilder sb = new StringBuilder();
            String poolName = sb.append(rule.getSrcIp().replace(".", "_"))
                    .append('-').append(rule.getSrcPortRange()[0]).toString();
            if (!rule.revoked()) {
                List<PortForwardingRuleTO> fwList = pools.get(poolName);
                if (fwList == null) {
                    fwList = new ArrayList<PortForwardingRuleTO>();
                    pools.put(poolName, fwList);
                }
                fwList.add(rule);
            }
        }

        List<String> result = new ArrayList<String>();

        result.addAll(Arrays.asList(globalSection));
        result.add(blankLine);
        result.addAll(Arrays.asList(defaultsSection));
        result.add(blankLine);

        if (pools.isEmpty()) {
            // haproxy cannot handle empty listen / frontend or backend, so add
            // a dummy listener
            // on port 9
            result.addAll(Arrays.asList(defaultListen));
        }
        result.add(blankLine);

        for (Map.Entry<String, List<PortForwardingRuleTO>> e : pools.entrySet()) {
            List<String> poolRules = getRulesForPool(e.getKey(), e.getValue());
            result.addAll(poolRules);
        }

        return result.toArray(new String[result.size()]);
    }

    private List<String> getRulesForPool(String poolName,
            List<PortForwardingRuleTO> fwRules) {
        PortForwardingRuleTO firstRule = fwRules.get(0);
        String publicIP = firstRule.getSrcIp();
        String publicPort = Integer.toString(firstRule.getSrcPortRange()[0]);
        // FIXEME: String algorithm = firstRule.getAlgorithm();

        List<String> result = new ArrayList<String>();
        // add line like this: "listen  65_37_141_30-80 65.37.141.30:80"
        StringBuilder sb = new StringBuilder();
        sb.append("listen ").append(poolName).append(" ").append(publicIP)
                .append(":").append(publicPort);
        result.add(sb.toString());
        sb = new StringBuilder();
        // FIXME sb.append("\t").append("balance ").append(algorithm);
        result.add(sb.toString());
        if (publicPort.equals(NetUtils.HTTP_PORT)) {
            sb = new StringBuilder();
            sb.append("\t").append("mode http");
            result.add(sb.toString());
            sb = new StringBuilder();
            sb.append("\t").append("option httpclose");
            result.add(sb.toString());
        }
        int i = 0;
        for (PortForwardingRuleTO rule : fwRules) {
            // add line like this: "server  65_37_141_30-80_3 10.1.1.4:80 check"
            if (rule.revoked()) {
                continue;
            }
            sb = new StringBuilder();
            sb.append("\t").append("server ").append(poolName).append("_")
                    .append(Integer.toString(i++)).append(" ")
                    .append(rule.getDstIp()).append(":")
                    .append(rule.getDstPortRange()[0]).append(" check");
            result.add(sb.toString());
        }
        result.add(blankLine);
        return result;
    }
 
  /*
  cookie <name> [ rewrite | insert | prefix ] [ indirect ] [ nocache ]
              [ postonly ] [ domain <domain> ]*
  Enable cookie-based persistence in a backend.
  May be used in sections :   defaults | frontend | listen | backend
                                 yes   |    no    |   yes  |   yes
  Arguments :
    <name>    is the name of the cookie which will be monitored, modified or
              inserted in order to bring persistence. This cookie is sent to
              the client via a "Set-Cookie" header in the response, and is
              brought back by the client in a "Cookie" header in all requests.
              Special care should be taken to choose a name which does not
              conflict with any likely application cookie. Also, if the same
              backends are subject to be used by the same clients (eg:
              HTTP/HTTPS), care should be taken to use different cookie names
              between all backends if persistence between them is not desired.

    rewrite   This keyword indicates that the cookie will be provided by the
              server and that haproxy will have to modify its value to set the
              server's identifier in it. This mode is handy when the management
              of complex combinations of "Set-cookie" and "Cache-control"
              headers is left to the application. The application can then
              decide whether or not it is appropriate to emit a persistence
              cookie. Since all responses should be monitored, this mode only
              works in HTTP close mode. Unless the application behaviour is
              very complex and/or broken, it is advised not to start with this
              mode for new deployments. This keyword is incompatible with
              "insert" and "prefix".

    insert    This keyword indicates that the persistence cookie will have to
              be inserted by haproxy in the responses. If the server emits a
              cookie with the same name, it will be replaced anyway. For this
              reason, this mode can be used to upgrade existing configurations
              running in the "rewrite" mode. The cookie will only be a session
              cookie and will not be stored on the client's disk. Due to
              caching effects, it is generally wise to add the "indirect" and
              "nocache" or "postonly" keywords (see below). The "insert"
              keyword is not compatible with "rewrite" and "prefix".

    prefix    This keyword indicates that instead of relying on a dedicated
              cookie for the persistence, an existing one will be completed.
              This may be needed in some specific environments where the client
              does not support more than one single cookie and the application
              already needs it. In this case, whenever the server sets a cookie
              named <name>, it will be prefixed with the server's identifier
              and a delimiter. The prefix will be removed from all client
              requests so that the server still finds the cookie it emitted.
              Since all requests and responses are subject to being modified,
              this mode requires the HTTP close mode. The "prefix" keyword is
              not compatible with "rewrite" and "insert".

    indirect  When this option is specified in insert mode, cookies will only
              be added when the server was not reached after a direct access,
              which means that only when a server is elected after applying a
              load-balancing algorithm, or after a redispatch, then the cookie
              will be inserted. If the client has all the required information
              to connect to the same server next time, no further cookie will
              be inserted. In all cases, when the "indirect" option is used in
              insert mode, the cookie is always removed from the requests
              transmitted to the server. The persistence mechanism then becomes
              totally transparent from the application point of view.

    nocache   This option is recommended in conjunction with the insert mode
              when there is a cache between the client and HAProxy, as it
              ensures that a cacheable response will be tagged non-cacheable if
              a cookie needs to be inserted. This is important because if all
              persistence cookies are added on a cacheable home page for
              instance, then all customers will then fetch the page from an
              outer cache and will all share the same persistence cookie,
              leading to one server receiving much more traffic than others.
              See also the "insert" and "postonly" options.

    postonly  This option ensures that cookie insertion will only be performed
              on responses to POST requests. It is an alternative to the
              "nocache" option, because POST responses are not cacheable, so
              this ensures that the persistence cookie will never get cached.
              Since most sites do not need any sort of persistence before the
              first POST which generally is a login request, this is a very
              efficient method to optimize caching without risking to find a
              persistence cookie in the cache.
              See also the "insert" and "nocache" options.

    domain    This option allows to specify the domain at which a cookie is
              inserted. It requires exactly one parameter: a valid domain
              name. If the domain begins with a dot, the browser is allowed to
              use it for any host ending with that name. It is also possible to
              specify several domain names by invoking this option multiple
              times. Some browsers might have small limits on the number of
              domains, so be careful when doing that. For the record, sending
              10 domains to MSIE 6 or Firefox 2 works as expected.

  There can be only one persistence cookie per HTTP backend, and it can be
  declared in a defaults section. The value of the cookie will be the value
  indicated after the "cookie" keyword in a "server" statement. If no cookie
  is declared for a given server, the cookie is not set.

  Examples :
        cookie JSESSIONID prefix
        cookie SRV insert indirect nocache
        cookie SRV insert postonly indirect
 
  
  appsession <cookie> len <length> timeout <holdtime>
           [request-learn] [prefix] [mode <path-parameters|query-string>]
  Define session stickiness on an existing application cookie.
  May be used in sections :   defaults | frontend | listen | backend
                                 no    |    no    |   yes  |   yes
  Arguments :
    <cookie>   this is the name of the cookie used by the application and which
               HAProxy will have to learn for each new session.

    <length>   this is the max number of characters that will be memorized and
               checked in each cookie value.

    <holdtime> this is the time after which the cookie will be removed from
               memory if unused. If no unit is specified, this time is in
               milliseconds.

    request-learn
               If this option is specified, then haproxy will be able to learn
               the cookie found in the request in case the server does not
               specify any in response. This is typically what happens with
               PHPSESSID cookies, or when haproxy's session expires before
               the application's session and the correct server is selected.
               It is recommended to specify this option to improve reliability.

    prefix     When this option is specified, haproxy will match on the cookie
               prefix (or URL parameter prefix). The appsession value is the
               data following this prefix.

               Example :
               appsession ASPSESSIONID len 64 timeout 3h prefix

               This will match the cookie ASPSESSIONIDXXXX=XXXXX,
               the appsession value will be XXXX=XXXXX.

    mode       This option allows to change the URL parser mode.
               2 modes are currently supported :
               - path-parameters :
                 The parser looks for the appsession in the path parameters
                 part (each parameter is separated by a semi-colon), which is
                 convenient for JSESSIONID for example.
                 This is the default mode if the option is not set.
               - query-string :
                 In this mode, the parser will look for the appsession in the
                 query string.

  When an application cookie is defined in a backend, HAProxy will check when
  the server sets such a cookie, and will store its value in a table, and
  associate it with the server's identifier. Up to <length> characters from
  the value will be retained. On each connection, haproxy will look for this
  cookie both in the "Cookie:" headers, and as a URL parameter (depending on
  the mode used). If a known value is found, the client will be directed to the
  server associated with this value. Otherwise, the load balancing algorithm is
  applied. Cookies are automatically removed from memory when they have been
  unused for a duration longer than <holdtime>.

  The definition of an application cookie is limited to one per backend.
  Example :
        appsession JSESSIONID len 52 timeout 3h
*/
    private String getLbSubRuleForStickiness(LoadBalancerTO lbTO) {
        int i = 0;
        
        if (lbTO.getStickinessPolicies() == null)
            return null;
        
        StringBuilder sb = new StringBuilder();

        for (StickinessPolicyTO stickinessPolicy : lbTO.getStickinessPolicies()) {
            if (stickinessPolicy == null)
                continue;
            List<Pair<String, String>> paramsList = stickinessPolicy.getParams();
            i++;
            
            /*
             * cookie <name> [ rewrite | insert | prefix ] [ indirect ] [ nocache ]
              [ postonly ] [ domain <domain> ]*
             
             */
            if (StickinessMethodType.LBCookieBased.getName().equalsIgnoreCase(stickinessPolicy.getMethodName())) {
                /* Default Values */
                String cookieName = null; // optional 
                String mode ="insert "; // optional
                Boolean indirect = false; // optional
                Boolean nocache = false; // optional
                Boolean postonly = false; // optional       
                StringBuilder domainSb = null ; // optional 

                for(Pair<String,String> paramKV :paramsList){
                    String key = paramKV.first();
                    String value = paramKV.second();
                    if ("cookie-name".equalsIgnoreCase(key)) cookieName = value;
                    if ("mode".equalsIgnoreCase(key)) mode = value;
                    if ("domain".equalsIgnoreCase(key)) {
                        if (domainSb == null) {
                            domainSb = new StringBuilder();
                        }
                        domainSb = domainSb.append("domain ");
                        domainSb.append(value).append(" ");
                    }
                    if ("indirect".equalsIgnoreCase(key)) indirect = true;
                    if ("nocache".equalsIgnoreCase(key)) nocache = true;
                    if ("postonly".equalsIgnoreCase(key)) postonly = true;
                }
                if (cookieName == null) {// re-check all haproxy mandatory params 
                    StringBuilder tempSb = new StringBuilder();
                    String srcip = lbTO.getSrcIp();
                    if (srcip == null)
                        srcip = "TESTCOOKIE";
                    tempSb.append("lbcooki_").append(srcip.hashCode())
                            .append("_").append(lbTO.getSrcPort());
                    cookieName = tempSb.toString();
                }
                sb.append("\t").append("cookie ").append(cookieName).append(" ").append(mode).append(" ");
                if (indirect) sb.append("indirect ");
                if (nocache) sb.append("nocache ");
                if (postonly) sb.append("postonly ");
                if (domainSb != null) sb.append(domainSb).append(" ");       
            } else if (StickinessMethodType.SourceBased.getName().equalsIgnoreCase(stickinessPolicy.getMethodName())) {
                /* Default Values */
                String tablesize = "200k"; // optional 
                String expire = "30m"; // optional 

                /* overwrite default values with the stick parameters */
                for(Pair<String,String> paramKV :paramsList){
                    String key = paramKV.first();
                    String value = paramKV.second();
                    if ("tablesize".equalsIgnoreCase(key)) tablesize = value;
                    if ("expire".equalsIgnoreCase(key)) expire = value;             
                }
                sb.append("\t").append("stick-table type ip size ")
                        .append(tablesize).append(" expire ").append(expire);
                sb.append("\n\t").append("stick on src");
            } else if (StickinessMethodType.AppCookieBased.getName().equalsIgnoreCase(stickinessPolicy.getMethodName())) {
                /*
                 * FORMAT : appsession <cookie> len <length> timeout <holdtime>
                 * [request-learn] [prefix] [mode
                 * <path-parameters|query-string>]
                 */
                /* example: appsession JSESSIONID len 52 timeout 3h */
                String cookieName = null; // optional 
                String length = "52"; // optional 
                String holdtime = "3h"; // optional 
                String mode = null; // optional 
                Boolean requestlearn = false; // optional 
                Boolean prefix = false; // optional 
                
                for(Pair<String,String> paramKV :paramsList){
                    String key = paramKV.first();
                    String value = paramKV.second();
                    if ("cookie-name".equalsIgnoreCase(key))   cookieName = value;
                    if ("length".equalsIgnoreCase(key)) length = value;                
                    if ("holdtime".equalsIgnoreCase(key))  holdtime = value;
                    if ("mode".equalsIgnoreCase(key))  mode = value;
                    if ("request-learn".equalsIgnoreCase(key)) requestlearn = true;
                    if ("prefix".equalsIgnoreCase(key)) prefix = true;
                }
                if (cookieName == null) {// re-check all haproxy mandatory params 
                    StringBuilder tempSb = new StringBuilder();
                    String srcip = lbTO.getSrcIp();
                    if (srcip == null)
                        srcip = "TESTCOOKIE";
                    tempSb.append("appcookie_").append(srcip.hashCode())
                            .append("_").append(lbTO.getSrcPort());
                    cookieName = tempSb.toString();
                }
                sb.append("\t").append("appsession ").append(cookieName)
                        .append(" len ").append(length).append(" timeout ")
                        .append(holdtime).append(" ");
                if (prefix) sb.append("prefix ");
                if (requestlearn) sb.append("request-learn").append(" ");
                if (mode != null) sb.append("mode ").append(mode).append(" ");
            } else {
                /* 
                 * Error is silently swallowed.
                 * Not supposed to reach here, validation of methods are
                 * done at the higher layer
                 */
                s_logger.warn("Haproxy stickiness policy for lb rule: " + lbTO.getSrcIp() + ":" + lbTO.getSrcPort() +": Not Applied, cause:invalid method ");
                return null;
            }
        }
        if (i == 0) return null;
        return sb.toString();
    }

    private List<String> getRulesForPool(LoadBalancerTO lbTO)  {
        StringBuilder sb = new StringBuilder();
        String poolName = sb.append(lbTO.getSrcIp().replace(".", "_"))
                .append('-').append(lbTO.getSrcPort()).toString();
        String publicIP = lbTO.getSrcIp();
        String publicPort = Integer.toString(lbTO.getSrcPort());
        String algorithm = lbTO.getAlgorithm();

        List<String> result = new ArrayList<String>();
        // add line like this: "listen  65_37_141_30-80 65.37.141.30:80"
        sb = new StringBuilder();
        sb.append("listen ").append(poolName).append(" ").append(publicIP)
                .append(":").append(publicPort);
        result.add(sb.toString());
        sb = new StringBuilder();
        sb.append("\t").append("balance ").append(algorithm);
        result.add(sb.toString());

        int i = 0;
        Boolean destsAvailable = false;
        String stickinessSubRule = getLbSubRuleForStickiness(lbTO);
        List<String>  dstSubRule = new ArrayList<String>();
        List<String>  dstWithCookieSubRule = new ArrayList<String>();
        for (DestinationTO dest : lbTO.getDestinations()) {
            // add line like this: "server  65_37_141_30-80_3 10.1.1.4:80 check"
            if (dest.isRevoked()) {
                continue;
            }
            sb = new StringBuilder();
            sb.append("\t").append("server ").append(poolName).append("_")
                    .append(Integer.toString(i++)).append(" ")
                    .append(dest.getDestIp()).append(":")
                    .append(dest.getDestPort()).append(" check");
            dstSubRule.add(sb.toString());
            if (stickinessSubRule != null) {
                sb.append(" cookie ").append(dest.getDestIp().replace(".", "_"))
                .append('-').append(dest.getDestPort()).toString();
                dstWithCookieSubRule.add(sb.toString());
            }
            destsAvailable = true;
        }

        Boolean httpbasedStickiness = false;
        /* attach stickiness sub rule only if the destinations are available */
        if ((stickinessSubRule != null) && (destsAvailable == true)) {
            for (StickinessPolicyTO stickinessPolicy : lbTO.getStickinessPolicies()) {
                if (stickinessPolicy == null)
                    continue;
                if (StickinessMethodType.LBCookieBased.getName().equalsIgnoreCase(stickinessPolicy.getMethodName()) || StickinessMethodType.AppCookieBased.getName().equalsIgnoreCase(stickinessPolicy.getMethodName())) {
                    httpbasedStickiness = true;
                }
            }
            if (httpbasedStickiness) {
                result.addAll(dstWithCookieSubRule);
            }else {
                result.addAll(dstSubRule);
            }
            result.add(stickinessSubRule);
        }else {
            result.addAll(dstSubRule);
        }
        if ((stickinessSubRule != null) && !destsAvailable) {
            s_logger.warn("Haproxy stickiness policy for lb rule: " + lbTO.getSrcIp() + ":" + lbTO.getSrcPort() +": Not Applied, cause:  backends are unavailable");
        }
        if ((publicPort.equals(NetUtils.HTTP_PORT)) || (httpbasedStickiness) ) {
            sb = new StringBuilder();
            sb.append("\t").append("mode http");
            result.add(sb.toString());
            sb = new StringBuilder();
            sb.append("\t").append("option httpclose");
            result.add(sb.toString());
        }
        
        result.add(blankLine);
        return result;
    }

    private String generateStatsRule(LoadBalancerConfigCommand lbCmd,
            String ruleName, String statsIp) {
        StringBuilder rule = new StringBuilder("\nlisten ").append(ruleName)
                .append(" ").append(statsIp).append(":")
                .append(lbCmd.lbStatsPort);
        rule.append(
                "\n\tmode http\n\toption httpclose\n\tstats enable\n\tstats uri     ")
                .append(lbCmd.lbStatsUri)
                .append("\n\tstats realm   Haproxy\\ Statistics\n\tstats auth    ")
                .append(lbCmd.lbStatsAuth);
        rule.append("\n");
        return rule.toString();
    }

    @Override
    public String[] generateConfiguration(LoadBalancerConfigCommand lbCmd)   {
        List<String> result = new ArrayList<String>();
        List <String> gSection =  Arrays.asList(globalSection);
        gSection.set(2,"\tmaxconn " + lbCmd.maxconn);
        result.addAll(gSection);
        result.add(blankLine);
        result.addAll(Arrays.asList(defaultsSection));
        if (!lbCmd.lbStatsVisibility.equals("disabled")) {
            /* new rule : listen admin_page guestip/link-local:8081 */
            if (lbCmd.lbStatsVisibility.equals("global")) {
                result.add(generateStatsRule(lbCmd, "stats_on_public",
                        lbCmd.lbStatsPublicIP));
            } else if (lbCmd.lbStatsVisibility.equals("guest-network")) {
                result.add(generateStatsRule(lbCmd, "stats_on_guest",
                        lbCmd.lbStatsGuestIP));
            } else if (lbCmd.lbStatsVisibility.equals("link-local")) {
                result.add(generateStatsRule(lbCmd, "stats_on_private",
                        lbCmd.lbStatsPrivateIP));
            } else if (lbCmd.lbStatsVisibility.equals("all")) {
                result.add(generateStatsRule(lbCmd, "stats_on_public",
                        lbCmd.lbStatsPublicIP));
                result.add(generateStatsRule(lbCmd, "stats_on_guest",
                        lbCmd.lbStatsGuestIP));
                result.add(generateStatsRule(lbCmd, "stats_on_private",
                        lbCmd.lbStatsPrivateIP));
            } else {
                /*
                 * stats will be available on the default http serving port, no
                 * special stats port
                 */
                StringBuilder subRule = new StringBuilder(
                        "\tstats enable\n\tstats uri     ")
                        .append(lbCmd.lbStatsUri)
                        .append("\n\tstats realm   Haproxy\\ Statistics\n\tstats auth    ")
                        .append(lbCmd.lbStatsAuth);
                result.add(subRule.toString());
            }

        }
        result.add(blankLine);
        boolean has_listener = false;
        for (LoadBalancerTO lbTO : lbCmd.getLoadBalancers()) {
            if ( lbTO.isRevoked() ) {
                continue;
            }
            List<String> poolRules = getRulesForPool(lbTO);
            result.addAll(poolRules);
            has_listener = true;
        }
        result.add(blankLine);
        if ( !has_listener) {
            // haproxy cannot handle empty listen / frontend or backend, so add
            // a dummy listener
            // on port 9
            result.addAll(Arrays.asList(defaultListen));
        }
        return result.toArray(new String[result.size()]);
    }

    @Override
    public String[][] generateFwRules(LoadBalancerConfigCommand lbCmd) {
        String[][] result = new String[3][];
        Set<String> toAdd = new HashSet<String>();
        Set<String> toRemove = new HashSet<String>();
        Set<String> toStats = new HashSet<String>();

        for (LoadBalancerTO lbTO : lbCmd.getLoadBalancers()) {

            StringBuilder sb = new StringBuilder();
            sb.append(lbTO.getSrcIp()).append(":");
            sb.append(lbTO.getSrcPort()).append(":");
            String lbRuleEntry = sb.toString();
            if (!lbTO.isRevoked()) {
                toAdd.add(lbRuleEntry);
            } else {
                toRemove.add(lbRuleEntry);
            }
        }
        StringBuilder sb = new StringBuilder("");
        if (lbCmd.lbStatsVisibility.equals("guest-network")) {
            sb = new StringBuilder(lbCmd.lbStatsGuestIP).append(":")
                    .append(lbCmd.lbStatsPort).append(":")
                    .append(lbCmd.lbStatsSrcCidrs).append(":,");
        } else if (lbCmd.lbStatsVisibility.equals("link-local")) {
            sb = new StringBuilder(lbCmd.lbStatsPrivateIP).append(":")
                    .append(lbCmd.lbStatsPort).append(":")
                    .append(lbCmd.lbStatsSrcCidrs).append(":,");
        } else if (lbCmd.lbStatsVisibility.equals("global")) {
            sb = new StringBuilder(lbCmd.lbStatsPublicIP).append(":")
                    .append(lbCmd.lbStatsPort).append(":")
                    .append(lbCmd.lbStatsSrcCidrs).append(":,");
        } else if (lbCmd.lbStatsVisibility.equals("all")) {
            sb = new StringBuilder("0.0.0.0/0").append(":")
                    .append(lbCmd.lbStatsPort).append(":")
                    .append(lbCmd.lbStatsSrcCidrs).append(":,");
        }
        toStats.add(sb.toString());

        toRemove.removeAll(toAdd);
        result[ADD] = toAdd.toArray(new String[toAdd.size()]);
        result[REMOVE] = toRemove.toArray(new String[toRemove.size()]);
        result[STATS] = toStats.toArray(new String[toStats.size()]);

        return result;
    }
}
