PluginServices.h

/********************************************************************************
 *    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_PLUGINSERVICES_H
#define FAIR_MQ_PLUGINSERVICES_H

#include <fairmq/Tools.h>
#include <FairMQDevice.h>
#include <options/FairMQProgOptions.h>

#include <boost/optional.hpp>
#include <boost/optional/optional_io.hpp>

#include <functional>
#include <string>
#include <unordered_map>
#include <mutex>
#include <condition_variable>

namespace fair
{
namespace mq
{

class PluginServices
{
  public:
    PluginServices() = delete;
    PluginServices(FairMQProgOptions* config, std::shared_ptr<FairMQDevice> device)
        : fConfig{config}
        , fDevice{device}
        , fDeviceController()
        , fDeviceControllerMutex()
        , fReleaseDeviceControlCondition()
    {
    }

    PluginServices(const PluginServices&) = delete;
    PluginServices operator=(const PluginServices&) = delete;

    enum class DeviceState : int
    {
        Ok,
        Error,
        Idle,
        InitializingDevice,
        DeviceReady,
        InitializingTask,
        Ready,
        Running,
        Paused,
        ResettingTask,
        ResettingDevice,
        Exiting
    };

    enum class DeviceStateTransition : int // transition event between DeviceStates
    {
        InitDevice,
        InitTask,
        Run,
        Pause,
        Resume,
        Stop,
        ResetTask,
        ResetDevice,
        End,
        ErrorFound
    };

    // Control API

    static auto ToDeviceState(const std::string& state) -> DeviceState { return fkDeviceStateStrMap.at(state); }

    static auto ToDeviceStateTransition(const std::string& transition) -> DeviceStateTransition { return fkDeviceStateTransitionStrMap.at(transition); }

    static auto ToStr(DeviceState state) -> std::string { return fkStrDeviceStateMap.at(state); }

    static auto ToStr(DeviceStateTransition transition) -> std::string { return fkStrDeviceStateTransitionMap.at(transition); }

    friend auto operator<<(std::ostream& os, const DeviceState& state) -> std::ostream& { return os << ToStr(state); }
    friend auto operator<<(std::ostream& os, const DeviceStateTransition& transition) -> std::ostream& { return os << ToStr(transition); }

    auto GetCurrentDeviceState() const -> DeviceState { return fkDeviceStateMap.at(static_cast<FairMQDevice::State>(fDevice->GetCurrentState())); }

    auto TakeDeviceControl(const std::string& controller) -> void;
    struct DeviceControlError : std::runtime_error { using std::runtime_error::runtime_error; };

    auto StealDeviceControl(const std::string& controller) -> void;

    auto ReleaseDeviceControl(const std::string& controller) -> void;

    auto GetDeviceController() const -> boost::optional<std::string>;

    auto WaitForReleaseDeviceControl() -> void;

    auto ChangeDeviceState(const std::string& controller, const DeviceStateTransition next) -> void;

    auto SubscribeToDeviceStateChange(const std::string& subscriber, std::function<void(DeviceState /*newState*/)> callback) -> void
    {
        fDevice->SubscribeToStateChange(subscriber, [&,callback](FairMQDevice::State newState){
            callback(fkDeviceStateMap.at(newState));
        });
    }

    auto UnsubscribeFromDeviceStateChange(const std::string& subscriber) -> void { fDevice->UnsubscribeFromStateChange(subscriber); }

    // Config API
    struct PropertyNotFoundError : std::runtime_error { using std::runtime_error::runtime_error; };

    auto PropertyExists(const std::string& key) const -> bool { return fConfig->Count(key) > 0; }

    template<typename T>
    auto SetProperty(const std::string& key, T val) -> void
    {
        auto currentState = GetCurrentDeviceState();
        if (currentState == DeviceState::InitializingDevice)
        {
            fConfig->SetValue(key, val);
        }
        else
        {
            throw InvalidStateError{tools::ToString("PluginServices::SetProperty is not supported in device state ", currentState, ". Supported state is ", DeviceState::InitializingDevice, ".")};
        }
    }
    struct InvalidStateError : std::runtime_error { using std::runtime_error::runtime_error; };

    template<typename T>
    auto GetProperty(const std::string& key) const -> T {
        if (PropertyExists(key)) {
            return fConfig->GetValue<T>(key);
        }
        throw PropertyNotFoundError(fair::mq::tools::ToString("Config has no key: ", key));
    }

    auto GetPropertyAsString(const std::string& key) const -> std::string {
        if (PropertyExists(key)) {
            return fConfig->GetStringValue(key);
        }
        throw PropertyNotFoundError(fair::mq::tools::ToString("Config has no key: ", key));
    }

    auto GetChannelInfo() const -> std::unordered_map<std::string, int> { return fConfig->GetChannelInfo(); }

    auto GetPropertyKeys() const -> std::vector<std::string> { return fConfig->GetPropertyKeys(); }

    template<typename T>
    auto SubscribeToPropertyChange(const std::string& subscriber, std::function<void(const std::string& key, T)> callback) const -> void
    {
        fConfig->Subscribe<T>(subscriber, callback);
    }

    template<typename T>
    auto UnsubscribeFromPropertyChange(const std::string& subscriber) -> void { fConfig->Unsubscribe<T>(subscriber); }

    auto SubscribeToPropertyChangeAsString(const std::string& subscriber, std::function<void(const std::string& key, std::string)> callback) const -> void
    {
        fConfig->SubscribeAsString(subscriber, callback);
    }

    auto UnsubscribeFromPropertyChangeAsString(const std::string& subscriber) -> void { fConfig->UnsubscribeAsString(subscriber); }


    static const std::unordered_map<std::string, DeviceState> fkDeviceStateStrMap;
    static const std::unordered_map<DeviceState, std::string, tools::HashEnum<DeviceState>> fkStrDeviceStateMap;
    static const std::unordered_map<std::string, DeviceStateTransition> fkDeviceStateTransitionStrMap;
    static const std::unordered_map<DeviceStateTransition, std::string, tools::HashEnum<DeviceStateTransition>> fkStrDeviceStateTransitionMap;
    static const std::unordered_map<FairMQDevice::State, DeviceState, tools::HashEnum<FairMQDevice::State>> fkDeviceStateMap;
    static const std::unordered_map<DeviceStateTransition, FairMQDevice::Event, tools::HashEnum<DeviceStateTransition>> fkDeviceStateTransitionMap;

  private:
    FairMQProgOptions* fConfig; // TODO make it a shared pointer, once old AliceO2 code is cleaned up
    std::shared_ptr<FairMQDevice> fDevice;
    boost::optional<std::string> fDeviceController;
    mutable std::mutex fDeviceControllerMutex;
    std::condition_variable fReleaseDeviceControlCondition;
}; /* class PluginServices */

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

#endif /* FAIR_MQ_PLUGINSERVICES_H */