#pragma once

#include <map>
#include <memory>
#include <string>
#include <vector>
#include <sdbusplus/server.hpp>
#include <xyz/openbmc_project/Inventory/Manager/server.hpp>
#include "events.hpp"
#include "functor.hpp"
#include "types.hpp"

namespace phosphor
{
namespace inventory
{
namespace manager
{

template <typename T>
using ServerObject = T;

using ManagerIface =
    sdbusplus::xyz::openbmc_project::Inventory::server::Manager;

/** @struct PropertiesVariant
 *  @brief Wrapper for sdbusplus PropertiesVariant.
 *
 *  A wrapper is useful since MakeInterface is instantiated with 'int'
 *  to deduce the return type of its methods, which does not depend
 *  on T.
 *
 *  @tparam T - The sdbusplus server binding type.
 */
template <typename T, typename Enable = void>
struct PropertiesVariant {};

template <typename T>
struct PropertiesVariant<T, typename std::enable_if<std::is_object<T>::value>::type>
{
    using Type = typename T::PropertiesVariant;
};

template <typename T>
using PropertiesVariantType = typename PropertiesVariant<T>::Type;

/** @struct MakeInterface
 *  @brief Adapt an sdbusplus interface proxy.
 *
 *  Template instances are builder functions that create
 *  adapted sdbusplus interface proxy interface objects.
 *
 *  @tparam T - The type of the interface being adapted.
 */

template <typename T>
struct MakeInterface
{
    static any_ns::any make(
        sdbusplus::bus::bus& bus,
        const char* path,
        const Interface& props)
    {
        using InterfaceVariant =
            std::map<std::string, PropertiesVariantType<T>>;

        InterfaceVariant v;

        for (const auto& p : props)
        {
            v.emplace(
                p.first,
                convertVariant<PropertiesVariantType<T>>(p.second));
        }

        return any_ns::any(std::make_shared<T>(bus, path, v));
    }

    static void assign(const Interface& props, any_ns::any& holder)
    {
        auto& iface = *any_ns::any_cast<std::shared_ptr<T> &>(holder);
        for (const auto& p : props)
        {
            iface.setPropertyByName(
                p.first, convertVariant<PropertiesVariantType<T>>(p.second));
        }
    }
};

/** @class Manager
 *  @brief OpenBMC inventory manager implementation.
 *
 *  A concrete implementation for the xyz.openbmc_project.Inventory.Manager
 *  DBus API.
 */
class Manager final :
    public ServerObject<ManagerIface>
{
    public:
        Manager() = delete;
        Manager(const Manager&) = delete;
        Manager& operator=(const Manager&) = delete;
        Manager(Manager&&) = default;
        Manager& operator=(Manager&&) = default;
        ~Manager() = default;

        /** @brief Construct an inventory manager.
         *
         *  @param[in] bus - An sdbusplus bus connection.
         *  @param[in] busname - The DBus busname to own.
         *  @param[in] root - The DBus path on which to implement
         *      an inventory manager.
         *  @param[in] iface - The DBus inventory interface to implement.
         */
        Manager(sdbusplus::bus::bus&&, const char*, const char*, const char*);

        using EventInfo = std::tuple <
                          std::vector<EventBasePtr>,
                          std::vector<Action >>;

        /** @brief Start processing DBus messages. */
        void run() noexcept;

        /** @brief Provided for testing only. */
        void shutdown() noexcept;

        /** @brief sd_bus Notify method implementation callback. */
        void notify(
            std::map<sdbusplus::message::object_path, Object> objs) override;

        /** @brief Event processing entry point. */
        void handleEvent(sdbusplus::message::message&,
                         const Event& event,
                         const EventInfo& info);

        /** @brief Drop one or more objects from DBus. */
        void destroyObjects(
            const std::vector<const char*>& paths);

        /** @brief Add objects to DBus. */
        void createObjects(
            const std::map<sdbusplus::message::object_path, Object>& objs);

        /** @brief Add or update objects on DBus. */
        void updateObjects(
            const std::map<sdbusplus::message::object_path, Object>& objs);

        /** @brief Invoke an sdbusplus server binding method.
         *
         *  Invoke the requested method with a reference to the requested
         *  sdbusplus server binding interface as a parameter.
         *
         *  @tparam T - The sdbusplus server binding interface type.
         *  @tparam U - The type of the sdbusplus server binding member.
         *  @tparam Args - Argument types of the binding member.
         *
         *  @param[in] path - The DBus path on which the method should
         *      be invoked.
         *  @param[in] interface - The DBus interface hosting the method.
         *  @param[in] member - Pointer to sdbusplus server binding member.
         *  @param[in] args - Arguments to forward to the binding member.
         *
         *  @returns - The return/value type of the binding method being
         *      called.
         */
        template<typename T, typename U, typename ...Args>
        decltype(auto) invokeMethod(const char* path, const char* interface,
                                    U&& member, Args&& ...args)
        {
            auto& iface = getInterface<T>(path, interface);
            return (iface.*member)(std::forward<Args>(args)...);
        }

        using SigArgs = std::vector <
                        std::unique_ptr <
                        std::tuple <
                        Manager*,
                        const DbusSignal*,
                        const EventInfo* >>>;
        using SigArg = SigArgs::value_type::element_type;

    private:
        using InterfaceComposite = std::map<std::string, any_ns::any>;
        using ObjectReferences = std::map<std::string, InterfaceComposite>;
        using Events = std::vector<EventInfo>;

        // The int instantiations are safe since the signature of these
        // functions don't change from one instantiation to the next.
        using MakerType = std::add_pointer_t <
                          decltype(MakeInterface<int>::make) >;
        using AssignerType = std::add_pointer_t <
                             decltype(MakeInterface<int>::assign) >;
        using Makers = std::map<std::string, std::tuple<MakerType, AssignerType>>;

        /** @brief Provides weak references to interface holders.
         *
         *  Common code for all types for the templated getInterface
         *  methods.
         *
         *  @param[in] path - The DBus path for which the interface
         *      holder instance should be provided.
         *  @param[in] interface - The DBus interface for which the
         *      holder instance should be provided.
         *
         *  @returns A weak reference to the holder instance.
         */
        const any_ns::any& getInterfaceHolder(
            const char*, const char*) const;
        any_ns::any& getInterfaceHolder(
            const char*, const char*);

        /** @brief Provides weak references to interface holders.
         *
         *  @tparam T - The sdbusplus server binding interface type.
         *
         *  @param[in] path - The DBus path for which the interface
         *      should be provided.
         *  @param[in] interface - The DBus interface to obtain.
         *
         *  @returns A weak reference to the interface holder.
         */
        template<typename T>
        auto& getInterface(const char* path, const char* interface)
        {
            auto& holder = getInterfaceHolder(path, interface);
            return *any_ns::any_cast<std::shared_ptr<T> &>(holder);
        }
        template<typename T>
        auto& getInterface(const char* path, const char* interface) const
        {
            auto& holder = getInterfaceHolder(path, interface);
            return *any_ns::any_cast<T>(holder);
        }

        /** @brief Add or update interfaces on DBus. */
        void updateInterfaces(
            const sdbusplus::message::object_path& path,
            const Object& interfaces,
            ObjectReferences::iterator pos,
            bool emitSignals = true);

        /** @brief Provided for testing only. */
        volatile bool _shutdown;

        /** @brief Path prefix applied to any relative paths. */
        const char* _root;

        /** @brief A container of sdbusplus server interface references. */
        ObjectReferences _refs;

        /** @brief A container contexts for signal callbacks. */
        SigArgs _sigargs;

        /** @brief A container of sdbusplus signal matches.  */
        std::vector<sdbusplus::bus::match_t> _matches;

        /** @brief Persistent sdbusplus DBus bus connection. */
        sdbusplus::bus::bus _bus;

        /** @brief sdbusplus org.freedesktop.DBus.ObjectManager reference. */
        sdbusplus::server::manager::manager _manager;

        /** @brief A container of pimgen generated events and responses.  */
        static const Events _events;

        /** @brief A container of pimgen generated factory methods.  */
        static const Makers _makers;
};

} // namespace manager
} // namespace inventory
} // namespace phosphor

// vim: tabstop=8 expandtab shiftwidth=4 softtabstop=4