/*
 * This file is part of PowerDNS or dnsdist.
 * Copyright -- PowerDNS.COM B.V. and its contributors
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * In addition, for the avoidance of any doubt, permission is granted to
 * link this program with OpenSSL and to (re)distribute the binaries
 * produced as the result of such linking.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "iputils.hh"
#include "dolog.hh"
#include "sstuff.hh"

#include "namespaces.hh"
#include "dnsdist.hh"
#include "threadname.hh"

GlobalStateHolder<vector<CarbonConfig> > g_carbon;
static time_t s_start = time(nullptr);

uint64_t uptimeOfProcess(const std::string& str)
{
  return time(nullptr) - s_start;
}

void carbonDumpThread()
{
  try
  {
    setThreadName("dnsdist/carbon");
    auto localCarbon = g_carbon.getLocal();
    for(int numloops=0;;++numloops) {
      if(localCarbon->empty()) {
        sleep(1);
        continue;
      }
      /* this is wrong, we use the interval of the first server
         for every single one of them */
      if(numloops) {
        const unsigned int interval = localCarbon->at(0).interval;
        sleep(interval);
      }

      for (const auto& conf : *localCarbon) {
        const auto& server = conf.server;
        const std::string& namespace_name = conf.namespace_name;
        std::string hostname = conf.ourname;
        if (hostname.empty()) {
          try {
            hostname = getCarbonHostName();
          }
          catch(const std::exception& e) {
            throw std::runtime_error(std::string("The 'ourname' setting in 'carbonServer()' has not been set and we are unable to determine the system's hostname: ") + e.what());
          }
        }
        const std::string& instance_name = conf.instance_name;

        try {
          Socket s(server.sin4.sin_family, SOCK_STREAM);
          s.setNonBlocking();
          s.connect(server);  // we do the connect so the attempt happens while we gather stats
          ostringstream str;
          time_t now=time(0);
          for(const auto& e : g_stats.entries) {
            str<<namespace_name<<"."<<hostname<<"."<<instance_name<<"."<<e.first<<' ';
            if(const auto& val = boost::get<pdns::stat_t*>(&e.second))
              str<<(*val)->load();
            else if (const auto& dval = boost::get<double*>(&e.second))
              str<<**dval;
            else
              str<<(*boost::get<DNSDistStats::statfunction_t>(&e.second))(e.first);
            str<<' '<<now<<"\r\n";
          }
          auto states = g_dstates.getLocal();
          for(const auto& state : *states) {
            string serverName = state->getName().empty() ? state->remote.toStringWithPort() : state->getName();
            boost::replace_all(serverName, ".", "_");
            const string base = namespace_name + "." + hostname + "." + instance_name + ".servers." + serverName + ".";
            str<<base<<"queries" << ' ' << state->queries.load() << " " << now << "\r\n";
            str<<base<<"responses" << ' ' << state->responses.load() << " " << now << "\r\n";
            str<<base<<"drops" << ' ' << state->reuseds.load() << " " << now << "\r\n";
            str<<base<<"latency" << ' ' << (state->availability != DownstreamState::Availability::Down ? state->latencyUsec/1000.0 : 0) << " " << now << "\r\n";
            str<<base<<"senderrors" << ' ' << state->sendErrors.load() << " " << now << "\r\n";
            str<<base<<"outstanding" << ' ' << state->outstanding.load() << " " << now << "\r\n";
            str<<base<<"tcpdiedsendingquery" << ' '<< state->tcpDiedSendingQuery.load() << " " << now << "\r\n";
            str<<base<<"tcpdiedreaddingresponse" << ' '<< state->tcpDiedReadingResponse.load() << " " << now << "\r\n";
            str<<base<<"tcpgaveup" << ' '<< state->tcpGaveUp.load() << " " << now << "\r\n";
            str<<base<<"tcpreadimeouts" << ' '<< state->tcpReadTimeouts.load() << " " << now << "\r\n";
            str<<base<<"tcpwritetimeouts" << ' '<< state->tcpWriteTimeouts.load() << " " << now << "\r\n";
            str<<base<<"tcpconnecttimeouts" << ' '<< state->tcpConnectTimeouts.load() << " " << now << "\r\n";
            str<<base<<"tcpcurrentconnections" << ' '<< state->tcpCurrentConnections.load() << " " << now << "\r\n";
            str<<base<<"tcpmaxconcurrentconnections" << ' '<< state->tcpMaxConcurrentConnections.load() << " " << now << "\r\n";
            str<<base<<"tcpnewconnections" << ' '<< state->tcpNewConnections.load() << " " << now << "\r\n";
            str<<base<<"tcpreusedconnections" << ' '<< state->tcpReusedConnections.load() << " " << now << "\r\n";
            str<<base<<"tlsresumptions" << ' '<< state->tlsResumptions.load() << " " << now << "\r\n";
            str<<base<<"tcpavgqueriesperconnection" << ' '<< state->tcpAvgQueriesPerConnection.load() << " " << now << "\r\n";
            str<<base<<"tcpavgconnectionduration" << ' '<< state->tcpAvgConnectionDuration.load() << " " << now << "\r\n";
          }

          std::map<std::string,uint64_t> frontendDuplicates;
          for(const auto& front : g_frontends) {
            if (front->udpFD == -1 && front->tcpFD == -1)
              continue;

            string frontName = front->local.toStringWithPort() + (front->udpFD >= 0 ? "_udp" : "_tcp");
            boost::replace_all(frontName, ".", "_");
            auto dupPair = frontendDuplicates.insert({frontName, 1});
            if (!dupPair.second) {
              frontName = frontName + "_" + std::to_string(dupPair.first->second);
              ++(dupPair.first->second);
            }

            const string base = namespace_name + "." + hostname + "." + instance_name + ".frontends." + frontName + ".";
            str<<base<<"queries" << ' ' << front->queries.load() << " " << now << "\r\n";
            str<<base<<"responses" << ' ' << front->responses.load() << " " << now << "\r\n";
            str<<base<<"tcpdiedreadingquery" << ' '<< front->tcpDiedReadingQuery.load() << " " << now << "\r\n";
            str<<base<<"tcpdiedsendingresponse" << ' '<< front->tcpDiedSendingResponse.load() << " " << now << "\r\n";
            str<<base<<"tcpgaveup" << ' '<< front->tcpGaveUp.load() << " " << now << "\r\n";
            str<<base<<"tcpclientimeouts" << ' '<< front->tcpClientTimeouts.load() << " " << now << "\r\n";
            str<<base<<"tcpdownstreamtimeouts" << ' '<< front->tcpDownstreamTimeouts.load() << " " << now << "\r\n";
            str<<base<<"tcpcurrentconnections" << ' '<< front->tcpCurrentConnections.load() << " " << now << "\r\n";
            str<<base<<"tcpmaxconcurrentconnections" << ' '<< front->tcpMaxConcurrentConnections.load() << " " << now << "\r\n";
            str<<base<<"tcpavgqueriesperconnection" << ' '<< front->tcpAvgQueriesPerConnection.load() << " " << now << "\r\n";
            str<<base<<"tcpavgconnectionduration" << ' '<< front->tcpAvgConnectionDuration.load() << " " << now << "\r\n";
            str<<base<<"tls10-queries" << ' ' << front->tls10queries.load() << " " << now << "\r\n";
            str<<base<<"tls11-queries" << ' ' << front->tls11queries.load() << " " << now << "\r\n";
            str<<base<<"tls12-queries" << ' ' << front->tls12queries.load() << " " << now << "\r\n";
            str<<base<<"tls13-queries" << ' ' << front->tls13queries.load() << " " << now << "\r\n";
            str<<base<<"tls-unknown-queries" << ' ' << front->tlsUnknownqueries.load() << " " << now << "\r\n";
            str<<base<<"tlsnewsessions" << ' ' << front->tlsNewSessions.load() << " " << now << "\r\n";
            str<<base<<"tlsresumptions" << ' ' << front->tlsResumptions.load() << " " << now << "\r\n";
            str<<base<<"tlsunknownticketkeys" << ' ' << front->tlsUnknownTicketKey.load() << " " << now << "\r\n";
            str<<base<<"tlsinactiveticketkeys" << ' ' << front->tlsInactiveTicketKey.load() << " " << now << "\r\n";
            const TLSErrorCounters* errorCounters = nullptr;
            if (front->tlsFrontend != nullptr) {
              errorCounters = &front->tlsFrontend->d_tlsCounters;
            }
            else if (front->dohFrontend != nullptr) {
              errorCounters = &front->dohFrontend->d_tlsCounters;
            }
            if (errorCounters != nullptr) {
              str<<base<<"tlsdhkeytoosmall" << ' ' << errorCounters->d_dhKeyTooSmall << " " << now << "\r\n";
              str<<base<<"tlsinappropriatefallback" << ' ' << errorCounters->d_inappropriateFallBack << " " << now << "\r\n";
              str<<base<<"tlsnosharedcipher" << ' ' << errorCounters->d_noSharedCipher << " " << now << "\r\n";
              str<<base<<"tlsunknownciphertype" << ' ' << errorCounters->d_unknownCipherType << " " << now << "\r\n";
              str<<base<<"tlsunknownkeyexchangetype" << ' ' << errorCounters->d_unknownKeyExchangeType << " " << now << "\r\n";
              str<<base<<"tlsunknownprotocol" << ' ' << errorCounters->d_unknownProtocol << " " << now << "\r\n";
              str<<base<<"tlsunsupportedec" << ' ' << errorCounters->d_unsupportedEC << " " << now << "\r\n";
              str<<base<<"tlsunsupportedprotocol" << ' ' << errorCounters->d_unsupportedProtocol << " " << now << "\r\n";
            }
          }

          auto localPools = g_pools.getLocal();
          for (const auto& entry : *localPools) {
            string poolName = entry.first;
            boost::replace_all(poolName, ".", "_");
            if (poolName.empty()) {
              poolName = "_default_";
            }
            const string base = namespace_name + "." + hostname + "." + instance_name + ".pools." + poolName + ".";
            const std::shared_ptr<ServerPool> pool = entry.second;
            str<<base<<"servers" << " " << pool->countServers(false) << " " << now << "\r\n";
            str<<base<<"servers-up" << " " << pool->countServers(true) << " " << now << "\r\n";
            if (pool->packetCache != nullptr) {
              const auto& cache = pool->packetCache;
              str<<base<<"cache-size" << " " << cache->getMaxEntries() << " " << now << "\r\n";
              str<<base<<"cache-entries" << " " << cache->getEntriesCount() << " " << now << "\r\n";
              str<<base<<"cache-hits" << " " << cache->getHits() << " " << now << "\r\n";
              str<<base<<"cache-misses" << " " << cache->getMisses() << " " << now << "\r\n";
              str<<base<<"cache-deferred-inserts" << " " << cache->getDeferredInserts() << " " << now << "\r\n";
              str<<base<<"cache-deferred-lookups" << " " << cache->getDeferredLookups() << " " << now << "\r\n";
              str<<base<<"cache-lookup-collisions" << " " << cache->getLookupCollisions() << " " << now << "\r\n";
              str<<base<<"cache-insert-collisions" << " " << cache->getInsertCollisions() << " " << now << "\r\n";
              str<<base<<"cache-ttl-too-shorts" << " " << cache->getTTLTooShorts() << " " << now << "\r\n";
            }
          }

#ifdef HAVE_DNS_OVER_HTTPS
          {
            std::map<std::string,uint64_t> dohFrontendDuplicates;
            const string base = "dnsdist." + hostname + ".main.doh.";
            for(const auto& doh : g_dohlocals) {
              string name = doh->d_local.toStringWithPort();
              boost::replace_all(name, ".", "_");
              boost::replace_all(name, ":", "_");
              boost::replace_all(name, "[", "_");
              boost::replace_all(name, "]", "_");

              auto dupPair = dohFrontendDuplicates.insert({name, 1});
              if (!dupPair.second) {
                name = name + "_" + std::to_string(dupPair.first->second);
                ++(dupPair.first->second);
              }

              vector<pair<const char*, const pdns::stat_t&>> v{
                {"http-connects", doh->d_httpconnects},
                {"http1-queries", doh->d_http1Stats.d_nbQueries},
                {"http2-queries", doh->d_http2Stats.d_nbQueries},
                {"http1-200-responses", doh->d_http1Stats.d_nb200Responses},
                {"http2-200-responses", doh->d_http2Stats.d_nb200Responses},
                {"http1-400-responses", doh->d_http1Stats.d_nb400Responses},
                {"http2-400-responses", doh->d_http2Stats.d_nb400Responses},
                {"http1-403-responses", doh->d_http1Stats.d_nb403Responses},
                {"http2-403-responses", doh->d_http2Stats.d_nb403Responses},
                {"http1-500-responses", doh->d_http1Stats.d_nb500Responses},
                {"http2-500-responses", doh->d_http2Stats.d_nb500Responses},
                {"http1-502-responses", doh->d_http1Stats.d_nb502Responses},
                {"http2-502-responses", doh->d_http2Stats.d_nb502Responses},
                {"http1-other-responses", doh->d_http1Stats.d_nbOtherResponses},
                {"http2-other-responses", doh->d_http2Stats.d_nbOtherResponses},
                {"get-queries", doh->d_getqueries},
                {"post-queries", doh->d_postqueries},
                {"bad-requests", doh->d_badrequests},
                {"error-responses", doh->d_errorresponses},
                {"redirect-responses", doh->d_redirectresponses},
                {"valid-responses", doh->d_validresponses}
              };

              for(const auto& item : v) {
                str<<base<<name<<"."<<item.first << " " << item.second << " " << now <<"\r\n";
              }
            }
          }
#endif /* HAVE_DNS_OVER_HTTPS */

          {
            std::string qname;
            auto records = g_qcount.records.write_lock();
            for (const auto &record : *records) {
              qname = record.first;
              boost::replace_all(qname, ".", "_");
              str<<"dnsdist.querycount." << qname << ".queries " << record.second << " " << now << "\r\n";
            }
            records->clear();
          }

          const string msg = str.str();

          int ret = waitForRWData(s.getHandle(), false, 1 , 0);
          if(ret <= 0 ) {
            vinfolog("Unable to write data to carbon server on %s: %s", server.toStringWithPort(), (ret<0 ? stringerror() : "Timeout"));
            continue;
          }
          s.setBlocking();
          writen2(s.getHandle(), msg.c_str(), msg.size());
        }
        catch(const std::exception& e) {
          warnlog("Problem sending carbon data: %s", e.what());
        }
      }
    }
  }
  catch(const std::exception& e)
  {
    errlog("Carbon thread died: %s", e.what());
  }
  catch(const PDNSException& e)
  {
    errlog("Carbon thread died, PDNSException: %s", e.reason);
  }
  catch(...)
  {
    errlog("Carbon thread died");
  }
}