/********************************************************************************
 *    Copyright (C) 2017 GSI Helmholtzzentrum fuer Schwerionenforschung GmbH    *
 *                                                                              *
 *              This software is distributed under the terms of the             *
 *              GNU Lesser General Public Licence (LGPL) version 3,             *
 *                  copied verbatim in the file "LICENSE"                       *
 ********************************************************************************/

#ifndef FAIR_MQ_PLUGINS_DDS
#define FAIR_MQ_PLUGINS_DDS

#include <fairmq/Plugin.h>
#include <fairmq/Version.h>
#include <fairmq/StateQueue.h>

#include <DDS/dds_intercom.h>
#include <DDS/dds_env_prop.h>

#include <condition_variable>
#include <mutex>
#include <string>
#include <queue>
#include <thread>
#include <vector>
#include <unordered_map>
#include <set>
#include <chrono>
#include <functional>

namespace fair
{
namespace mq
{
namespace plugins
{

struct DDSConfig
{
    DDSConfig()
        : fSubChannelAddresses()
        , fDDSValues()
    {}

    // container of sub channel addresses
    std::vector<std::string> fSubChannelAddresses;
    // dds values for the channel
    std::unordered_map<uint64_t, std::string> fDDSValues;
};

struct IofN
{
    IofN(int i, int n)
        : fI(i)
        , fN(n)
        , fEntries()
    {}

    unsigned int fI;
    unsigned int fN;
    std::vector<std::string> fEntries;
};

class DDS : public Plugin
{
  public:
    DDS(const std::string& name, const Plugin::Version version, const std::string& maintainer, const std::string& homepage, PluginServices* pluginServices);

    ~DDS();

  private:
    auto HandleControl() -> void;

    auto FillChannelContainers() -> void;
    auto SubscribeForConnectingChannels() -> void;
    auto PublishBoundChannels() -> void;
    auto SubscribeForCustomCommands() -> void;

    auto HeartbeatSender() -> void;

    dds::intercom_api::CIntercomService fService;
    dds::intercom_api::CCustomCmd fDDSCustomCmd;
    dds::intercom_api::CKeyValue fDDSKeyValue;
    uint64_t fDDSTaskId;

    std::unordered_map<std::string, std::vector<std::string>> fBindingChans;
    std::unordered_map<std::string, DDSConfig> fConnectingChans;

    std::unordered_map<std::string, int> fI;
    std::unordered_map<std::string, IofN> fIofN;

    std::mutex fStopMutex;
    std::condition_variable fStopCondition;

    const std::set<std::string> fTransitions;

    std::thread fControllerThread;
    DeviceState fCurrentState, fLastState;
    fair::mq::StateQueue fStateQueue;

    std::atomic<bool> fDeviceTerminationRequested;
    std::atomic<bool> fServiceStarted;

    std::set<uint64_t> fHeartbeatSubscribers;
    std::mutex fHeartbeatSubscriberMutex;
    std::set<uint64_t> fStateChangeSubscribers;
    std::mutex fStateChangeSubscriberMutex;

    std::thread fHeartbeatThread;
    std::chrono::milliseconds fHeartbeatInterval;
};

Plugin::ProgOptions DDSProgramOptions()
{
    boost::program_options::options_description options{"DDS Plugin"};
    options.add_options()
        ("dds-i", boost::program_options::value<std::vector<std::string>>()->multitoken()->composing(), "Task index for chosing connection target (single channel n to m). When all values come via same update.")
        ("dds-i-n", boost::program_options::value<std::vector<std::string>>()->multitoken()->composing(), "Task index for chosing connection target (one out of n values to take). When values come as independent updates.");

    return options;
}

REGISTER_FAIRMQ_PLUGIN(
    DDS,                                         // Class name
    dds,                                         // Plugin name (string, lower case chars only)
    (Plugin::Version{FAIRMQ_VERSION_MAJOR,
                     FAIRMQ_VERSION_MINOR,
                     FAIRMQ_VERSION_PATCH}),     // Version
    "FairRootGroup <fairroot@gsi.de>",           // Maintainer
    "https://github.com/FairRootGroup/FairMQ",   // Homepage
    DDSProgramOptions                            // custom program options for the plugin
)

} /* namespace plugins */
} /* namespace mq */
} /* namespace fair */

#endif /* FAIR_MQ_PLUGINS_DDS */