/**
 *  Copyright (C) 2011 Cloud.com, Inc.  All rights reserved.
 */

package com.cloud.network;

import java.net.URI;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ScheduledExecutorService;

import javax.ejb.Local;
import javax.naming.ConfigurationException;

import org.apache.log4j.Logger;

import com.cloud.agent.AgentManager;
import com.cloud.agent.Listener;
import com.cloud.agent.api.AgentControlAnswer;
import com.cloud.agent.api.AgentControlCommand;
import com.cloud.agent.api.Answer;
import com.cloud.agent.api.Command;
import com.cloud.agent.api.DirectNetworkUsageAnswer;
import com.cloud.agent.api.DirectNetworkUsageCommand;
import com.cloud.agent.api.RecurringNetworkUsageCommand;
import com.cloud.agent.api.StartupCommand;
import com.cloud.agent.api.StartupTrafficMonitorCommand;
import com.cloud.api.commands.AddTrafficMonitorCmd;
import com.cloud.api.commands.DeleteTrafficMonitorCmd;
import com.cloud.api.commands.ListTrafficMonitorsCmd;
import com.cloud.configuration.Config;
import com.cloud.configuration.dao.ConfigurationDao;
import com.cloud.dc.DataCenterVO;
import com.cloud.dc.dao.DataCenterDao;
import com.cloud.event.EventTypes;
import com.cloud.event.UsageEventVO;
import com.cloud.event.dao.UsageEventDao;
import com.cloud.exception.AgentUnavailableException;
import com.cloud.exception.InvalidParameterValueException;
import com.cloud.host.DetailVO;
import com.cloud.host.Host;
import com.cloud.host.HostVO;
import com.cloud.host.Status;
import com.cloud.host.dao.HostDao;
import com.cloud.host.dao.HostDetailsDao;
import com.cloud.network.Network.GuestIpType;
import com.cloud.network.dao.IPAddressDao;
import com.cloud.network.dao.NetworkDao;
import com.cloud.network.resource.TrafficSentinelResource;
import com.cloud.server.api.response.TrafficMonitorResponse;
import com.cloud.usage.UsageIPAddressVO;
import com.cloud.user.AccountManager;
import com.cloud.user.AccountVO;
import com.cloud.user.User;
import com.cloud.user.UserContext;
import com.cloud.user.UserStatisticsVO;
import com.cloud.user.dao.UserStatisticsDao;
import com.cloud.utils.NumbersUtil;
import com.cloud.utils.component.Inject;
import com.cloud.utils.db.DB;
import com.cloud.utils.db.GlobalLock;
import com.cloud.utils.db.JoinBuilder;
import com.cloud.utils.db.SearchBuilder;
import com.cloud.utils.db.SearchCriteria;
import com.cloud.utils.db.SearchCriteria.Op;
import com.cloud.utils.db.Transaction;
import com.cloud.utils.exception.CloudRuntimeException;
import com.cloud.utils.net.MacAddress;

@Local(value = {NetworkUsageManager.class})
public class NetworkUsageManagerImpl implements NetworkUsageManager {
    public enum NetworkUsageResourceName {
        TrafficSentinel;
    }

    private static final org.apache.log4j.Logger s_logger = Logger.getLogger(NetworkUsageManagerImpl.class);
    protected String _name;
    @Inject HostDao _hostDao;
    @Inject AgentManager _agentMgr;
    @Inject IPAddressDao _ipAddressDao;
    @Inject UserStatisticsDao _statsDao;
    @Inject ConfigurationDao _configDao;
    @Inject UsageEventDao _eventDao;
    @Inject DataCenterDao _dcDao;
    @Inject HostDetailsDao _detailsDao;
    @Inject AccountManager _accountMgr;
    @Inject NetworkDao _networksDao = null;
    ScheduledExecutorService _executor;
    int _networkStatsInterval;
    protected SearchBuilder<IPAddressVO> AllocatedIpSearch;

    @Override
    public Host addTrafficMonitor(AddTrafficMonitorCmd cmd) {

        long zoneId = cmd.getZoneId();

        DataCenterVO zone = _dcDao.findById(zoneId);
        String zoneName;
        if (zone == null) {
            throw new InvalidParameterValueException("Could not find zone with ID: " + zoneId);
        } else {
            zoneName = zone.getName();
        }


        List<HostVO> trafficMonitorsInZone = _hostDao.listByTypeDataCenter(Host.Type.TrafficMonitor, zoneId);
        if (trafficMonitorsInZone.size() != 0) {
            throw new InvalidParameterValueException("Already added an traffic monitor in zone: " + zoneName);
        }

        URI uri;
        try {
            uri = new URI(cmd.getUrl());
        } catch (Exception e) {
            s_logger.debug(e);
            throw new InvalidParameterValueException(e.getMessage());
        }

        String ipAddress = uri.getHost();
        //String numRetries = params.get("numretries");
        //String timeout = params.get("timeout");

        TrafficSentinelResource resource = new TrafficSentinelResource();
        String guid = getTrafficMonitorGuid(zoneId, NetworkUsageResourceName.TrafficSentinel, ipAddress);

        Map<String, Object> hostParams = new HashMap<String, Object>();
        hostParams.put("zone", String.valueOf(zoneId));
        hostParams.put("ipaddress", ipAddress);
        hostParams.put("url", cmd.getUrl());
        //hostParams("numRetries", numRetries);
        //hostParams("timeout", timeout);
        hostParams.put("guid", guid);
        hostParams.put("name", guid);

        try {
            resource.configure(guid, hostParams);
        } catch (ConfigurationException e) {
            throw new CloudRuntimeException(e.getMessage());
        }

        Map<String, String> hostDetails = new HashMap<String, String>();
        hostDetails.put("url", cmd.getUrl());
        hostDetails.put("last_collection", ""+System.currentTimeMillis());

        Host trafficMonitor = _agentMgr.addHost(zoneId, resource, Host.Type.TrafficMonitor, hostDetails);
        return trafficMonitor;
    }

    public String getTrafficMonitorGuid(long zoneId, NetworkUsageResourceName name, String ip) {
        return zoneId + "-" + name + "-" + ip;
    }

    @Override
    public boolean deleteTrafficMonitor(DeleteTrafficMonitorCmd cmd) {
        long hostId = cmd.getId();
        User caller = _accountMgr.getActiveUser(UserContext.current().getCallerUserId());
        HostVO trafficMonitor = _hostDao.findById(hostId);
        if (trafficMonitor == null) {
            throw new InvalidParameterValueException("Could not find an traffic monitor with ID: " + hostId);
        }

        try {
            if (_agentMgr.maintain(hostId) && _agentMgr.deleteHost(hostId, false, false, caller)) {
                return true;
            } else {
                return false;
            }
        } catch (AgentUnavailableException e) {
            s_logger.debug(e);
            return false;
        }
    }

    @Override
    public List<HostVO> listTrafficMonitors(ListTrafficMonitorsCmd cmd) {
        long zoneId = cmd.getZoneId();
        return _hostDao.listByTypeDataCenter(Host.Type.TrafficMonitor, zoneId);
    }

    @Override
    public TrafficMonitorResponse getApiResponse(Host trafficMonitor) {
        Map<String, String> tmDetails = _detailsDao.findDetails(trafficMonitor.getId());
        TrafficMonitorResponse response = new TrafficMonitorResponse();
        response.setId(trafficMonitor.getId());
        response.setIpAddress(trafficMonitor.getPrivateIpAddress());
        response.setNumRetries(tmDetails.get("numRetries"));
        response.setTimeout(tmDetails.get("timeout"));
        return response;
    }

    @Override
    public boolean configure(String name, Map<String, Object> params) throws ConfigurationException {
        _name = name;

        AllocatedIpSearch = _ipAddressDao.createSearchBuilder();
        AllocatedIpSearch.and("allocated", AllocatedIpSearch.entity().getAllocatedTime(), Op.NNULL);
        AllocatedIpSearch.and("dc", AllocatedIpSearch.entity().getDataCenterId(), Op.EQ);
        SearchBuilder<NetworkVO> networkJoin = _networksDao.createSearchBuilder();
        networkJoin.and("guestType", networkJoin.entity().getGuestType(), Op.EQ);
        AllocatedIpSearch.join("network", networkJoin, AllocatedIpSearch.entity().getSourceNetworkId(), networkJoin.entity().getId(), JoinBuilder.JoinType.INNER);
        AllocatedIpSearch.done();
        
        _networkStatsInterval = NumbersUtil.parseInt(_configDao.getValue(Config.DirectNetworkStatsInterval.key()), 86400);
        _agentMgr.registerForHostEvents(new DirectNetworkStatsListener( _networkStatsInterval), true, false, false);
        return true;
    }

    @Override
    public boolean start() {
        return true;
    }

    @Override
    public boolean stop() {
        return true;
    }

    @Override
    public String getName() {
        return _name;
    }

    @Override
    public List<IPAddressVO> listAllocatedDirectIps(long zoneId) {
        SearchCriteria<IPAddressVO> sc = AllocatedIpSearch.create();
        sc.setParameters("dc", zoneId);
        sc.setJoinParameters("network", "guestType", GuestIpType.Direct);
        return _ipAddressDao.search(sc, null);
    }

    protected class DirectNetworkStatsListener implements Listener {

        private int _interval;

        private long mgmtSrvrId = MacAddress.getMacAddress().toLong();

        protected DirectNetworkStatsListener(int interval) {
            _interval = interval;
        }

        @Override
        public boolean isRecurring() {
            return true;
        }

        @Override @DB
        public boolean processAnswers(long agentId, long seq, Answer[] answers) {
            /*
             * Do not collect Direct Network usage stats if the Traffic Monitor is not owned by this mgmt server
             */
            HostVO host = _hostDao.findById(agentId);
            if(host != null) {
                if((host.getManagementServerId() == null) || (mgmtSrvrId != host.getManagementServerId())){
                    s_logger.warn("Not the owner. Not collecting Direct Network usage from  TrafficMonitor : "+agentId);
                    return false;
                }
            } else {
                s_logger.warn("Agent not found. Not collecting Direct Network usage from  TrafficMonitor : "+agentId);
                return false;
            }

            GlobalLock scanLock = GlobalLock.getInternLock("direct.network.usage.collect"+host.getDataCenterId());
            try {
                if (scanLock.lock(10)) {
                    try {
                        return collectDirectNetworkUsage(host);
                    } finally {
                        scanLock.unlock();
                    }
                }
            } finally {
                scanLock.releaseRef();
            }
            return false;
        }

        private boolean collectDirectNetworkUsage(HostVO host){
            s_logger.debug("Direct Network Usage stats collector is running...");

            long zoneId = host.getDataCenterId();
            DetailVO lastCollectDetail = _detailsDao.findDetail(host.getId(),"last_collection");
            if(lastCollectDetail == null){
                s_logger.warn("Last collection time not available. Skipping direct usage collection for Traffic Monitor: "+host.getId());
                return false;
            }
            Date lastCollection = new Date(new Long(lastCollectDetail.getValue()));

            //Get list of IPs currently allocated
            List<IPAddressVO> allocatedIps = listAllocatedDirectIps(zoneId);
            Calendar rightNow = Calendar.getInstance();

            // Allow 2 hours for traffic sentinel to populate historical traffic
            // This coule be made configurable

            rightNow.add(Calendar.HOUR_OF_DAY, -2);
            Date now = rightNow.getTime();  
            
            if(lastCollection.after(now)){
                s_logger.debug("Current time is less than 2 hours after last collection time : " + lastCollection.toString() + ". Skipping direct network usage collection");
                return false;
            }

            //Get IP Assign/Release events from lastCollection time till now
            List<UsageEventVO> IpEvents = _eventDao.listDirectIpEvents(lastCollection, now, zoneId);

            Map<String, Date> ipAssigment = new HashMap<String, Date>();
            List<UsageIPAddressVO> IpPartialUsage = new ArrayList<UsageIPAddressVO>(); //Ips which were allocated only for the part of collection duration
            List<UsageIPAddressVO> fullDurationIpUsage = new ArrayList<UsageIPAddressVO>(); //Ips which were allocated only for the entire collection duration

            // Use UsageEvents to track the IP assignment
            // Add them to IpUsage list with account_id , ip_address, alloc_date, release_date

            for (UsageEventVO IpEvent : IpEvents){
                String address = IpEvent.getResourceName();
                if(EventTypes.EVENT_NET_IP_ASSIGN.equals(IpEvent.getType())){
                    ipAssigment.put(address, IpEvent.getCreateDate());
                } else if(EventTypes.EVENT_NET_IP_RELEASE.equals(IpEvent.getType())) {
                    if(ipAssigment.containsKey(address)){
                        Date assigned = ipAssigment.get(address);
                        ipAssigment.remove(address);
                        IpPartialUsage.add(new UsageIPAddressVO(IpEvent.getAccountId(), address, assigned, IpEvent.getCreateDate()));
                    } else{
                        // Ip was assigned prior to lastCollection Date
                        IpPartialUsage.add(new UsageIPAddressVO(IpEvent.getAccountId(), address, lastCollection, IpEvent.getCreateDate()));
                    }
                }
            }

            List<String> IpList = new ArrayList<String>() ;
            for(IPAddressVO ip : allocatedIps){
                if(ip.getAccountId() == AccountVO.ACCOUNT_ID_SYSTEM){
                    //Ignore usage for system account
                    continue;
                }
                String address = (ip.getAddress()).toString();
                if(ipAssigment.containsKey(address)){
                    // Ip was assigned during the current period but not release till Date now
                    IpPartialUsage.add(new UsageIPAddressVO(ip.getAccountId(), address, ipAssigment.get(address), now));
                } else {
                    // Ip was not assigned or released during current period. Consider entire duration for usage calculation (lastCollection to now)
                    fullDurationIpUsage.add(new UsageIPAddressVO(ip.getAccountId(), address, lastCollection, now));
                    //Store just the Ips to send the list as part of DirectNetworkUsageCommand
                    IpList.add(address);
                }

            }

            List<UserStatisticsVO> collectedStats = new ArrayList<UserStatisticsVO>();

            //Get usage for Ips for which were assigned for the entire duration
            if(fullDurationIpUsage.size() > 0){
                DirectNetworkUsageCommand cmd = new DirectNetworkUsageCommand(IpList, lastCollection, now);
                DirectNetworkUsageAnswer answer = (DirectNetworkUsageAnswer) _agentMgr.easySend(host.getId(), cmd);
                if (answer == null || !answer.getResult()) {
                    String details = (answer != null) ? answer.getDetails() : "details unavailable";
                    String msg = "Unable to get network usage stats from " + host.getId() + " due to: " + details + ".";
                    s_logger.error(msg);
                } else {
                    for(UsageIPAddressVO usageIp : fullDurationIpUsage){
                        String publicIp = usageIp.getAddress();
                        long[] bytesSentRcvd = answer.get(publicIp);
                        Long bytesSent = bytesSentRcvd[0];
                        Long bytesRcvd = bytesSentRcvd[1];
                        if(bytesSent == null || bytesRcvd == null){
                            s_logger.debug("Incorrect bytes for IP: "+publicIp);
                            continue;
                        }
                        if(bytesSent == 0L && bytesRcvd == 0L){
                            s_logger.trace("Ignore zero bytes for IP: "+publicIp);
                            continue;
                        }
                        UserStatisticsVO stats = new UserStatisticsVO(usageIp.getAccountId(), zoneId, null, null, null, null);
                        stats.setCurrentBytesSent(bytesSent);
                        stats.setCurrentBytesReceived(bytesRcvd);
                        collectedStats.add(stats);
                    }
                }
            }

            //Get usage for Ips for which were assigned for part of the duration period
            for(UsageIPAddressVO usageIp : IpPartialUsage){
                IpList = new ArrayList<String>() ;
                IpList.add(usageIp.getAddress());
                DirectNetworkUsageCommand cmd = new DirectNetworkUsageCommand(IpList, usageIp.getAssigned(), usageIp.getReleased());
                DirectNetworkUsageAnswer answer = (DirectNetworkUsageAnswer) _agentMgr.easySend(host.getId(), cmd);
                if (answer == null || !answer.getResult()) {
                    String details = (answer != null) ? answer.getDetails() : "details unavailable";
                    String msg = "Unable to get network usage stats from " + host.getId() + " due to: " + details + ".";
                    s_logger.error(msg);
                } else {
                    String publicIp = usageIp.getAddress();
                    long[] bytesSentRcvd = answer.get(publicIp);
                    Long bytesSent = bytesSentRcvd[0];
                    Long bytesRcvd = bytesSentRcvd[1];
                    if(bytesSent == null || bytesRcvd == null){
                        s_logger.debug("Incorrect bytes for IP: "+publicIp);
                        continue;
                    }
                    if(bytesSent == 0L && bytesRcvd == 0L){
                        s_logger.trace("Ignore zero bytes for IP: "+publicIp);
                        continue;
                    }
                    UserStatisticsVO stats = new UserStatisticsVO(usageIp.getAccountId(), zoneId, null, null, null, null);
                    stats.setCurrentBytesSent(bytesSent);
                    stats.setCurrentBytesReceived(bytesRcvd);
                    collectedStats.add(stats);

                }
            }

            //Persist all the stats and last_collection time in a single transaction
            Transaction txn = Transaction.open(Transaction.CLOUD_DB);
            try {
                txn.start();
                for(UserStatisticsVO stat : collectedStats){
                    UserStatisticsVO stats = _statsDao.lock(stat.getAccountId(), stat.getDataCenterId(), 0L, null, host.getId(), "DirectNetwork");
                    if (stats == null) {
                        stats = new UserStatisticsVO(stat.getAccountId(), zoneId, null, host.getId(), "DirectNetwork", 0L);
                        stats.setCurrentBytesSent(stat.getCurrentBytesSent());
                        stats.setCurrentBytesReceived(stat.getCurrentBytesReceived());
                        _statsDao.persist(stats);
                    } else {
                        stats.setCurrentBytesSent(stats.getCurrentBytesSent() + stat.getCurrentBytesSent());
                        stats.setCurrentBytesReceived(stats.getCurrentBytesReceived() + stat.getCurrentBytesReceived());
                        _statsDao.update(stats.getId(), stats);
                    }
                }
                lastCollectDetail.setValue(""+now.getTime());
                _detailsDao.update(lastCollectDetail.getId(), lastCollectDetail);
                txn.commit();
            } finally {
                txn.close();
            }

            return true;
        }

        @Override
        public boolean processCommands(long agentId, long seq, Command[] commands) {
            return false;
        }

        @Override
        public AgentControlAnswer processControlCommand(long agentId, AgentControlCommand cmd) {
            return null;
        }

        @Override
        public boolean processDisconnect(long agentId, Status state) {
            if (s_logger.isDebugEnabled()) {
                s_logger.debug("Disconnected called on " + agentId + " with status " + state.toString());
            }
            return true;
        }

        @Override
        public void processConnect(HostVO agent, StartupCommand cmd, boolean forRebalance) {
            if (cmd instanceof StartupTrafficMonitorCommand) {
                long agentId = agent.getId();
                s_logger.debug("Sending RecurringNetworkUsageCommand to " + agentId);
                RecurringNetworkUsageCommand watch = new RecurringNetworkUsageCommand(_interval);
                _agentMgr.gatherStats(agentId, watch, this);
            }
            return;
        }

        @Override
        public boolean processTimeout(long agentId, long seq) {
            return true;
        }

        @Override
        public int getTimeout() {
            return -1;
        }

        protected DirectNetworkStatsListener() {
        }
        

    }

}