#pragma once

#include <chrono>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <exception>

#include <DynamicOutput/DynamicOutput.hpp>
#include <Unreal/UObject.hpp>

#include <Static/LogGate.hpp>

namespace PalUIExtension::Features
{
    using namespace RC;
    using namespace RC::Unreal;

    class IUIFeature
    {
    public:
        using StringType = std::basic_string<TCHAR>;

        virtual ~IUIFeature() = default;

        virtual auto Name() const -> const TCHAR* = 0;

        virtual auto InstallHooks() -> void = 0;

        virtual auto OnWorldTeardown() -> void {}

        virtual auto SetEnabled(bool enabled) -> void {}

        virtual auto GetEnabled() -> bool { return false; }







        // ---- logging ---------------------------------------------------

        template <typename... Args>
        auto SendLog(LogLevel::LogLevel Level, const TCHAR* Fmt, Args&&... Fargs) const -> void
        {
           Emit(Level, Fmt, std::forward<Args>(Fargs)...);
        }

        template <typename... Args>
        auto SendLogOnce(const TCHAR* Key, LogLevel::LogLevel Level, const TCHAR* Fmt, Args&&... Fargs) const -> void
        {
            if (!Key) return;
            if (!m_log_once_keys.insert(StringType{ Key }).second) return;

            Emit(Level, Fmt, std::forward<Args>(Fargs)...);
        }

        template <typename... Args>
        auto SendLogThrottled(const TCHAR* Key, int64_t IntervalMs, LogLevel::LogLevel Level, const TCHAR* Fmt, Args&&... Fargs) const -> void
        {
            if (!Key) return;

            using Clock = std::chrono::steady_clock;
            const auto Now = Clock::now();

            auto& Last = m_log_throttle[StringType{ Key }];
            if (Last.time_since_epoch().count() != 0 && std::chrono::duration_cast<std::chrono::milliseconds>(Now - Last).count() < IntervalMs)
            {
                return;
            }
            Last = Now;

            Emit(Level, Fmt, std::forward<Args>(Fargs)...);
        }

        template <typename... Args>
        auto SendVerbose(const TCHAR* Fmt, Args&&... Fargs) const -> void
        {
            if constexpr (Static::kVerboseLogging)
            {
                Emit(LogLevel::Verbose, Fmt, std::forward<Args>(Fargs)...);
            }
        }

        auto ResetLogOnce() const -> void
        {
            m_log_once_keys.clear();
            m_log_throttle.clear();
        }

        // ---- argument helpers -------------------------------------------
        static auto NameOf(UObject* Obj) -> StringType          {            return Obj ? Obj->GetName() : StringType{ STR("<null>") };             }

        static auto FullNameOf(UObject* Obj) -> StringType      {            return Obj ? Obj->GetFullName() : StringType{ STR("<null>") };         }

        static auto ClassNameOf(UObject* Obj) -> StringType
        {
            if (!Obj) return StringType{ STR("<null>") };
            UClass* Cls = Obj->GetClassPrivate();
            return Cls ? Cls->GetName() : StringType{ STR("<no class>") };
        }

        static auto AddressOf(const void* P) -> uint64_t
        {
            return static_cast<uint64_t>(reinterpret_cast<uintptr_t>(P));
        }

    private:
        template <typename... Args>
        auto Emit(LogLevel::LogLevel Level, const TCHAR* Fmt, Args&&... Fargs) const -> void
        {
            if (!Fmt) return;

            try
            {
                switch (Level)
                {
                case LogLevel::Error:
                    Output::send<LogLevel::Error>(STR("PalUIExt [{}] "), Name());
                    Output::send<LogLevel::Error>(Fmt, std::forward<Args>(Fargs)...);
                    Output::send<LogLevel::Error>(STR("\n"));
                    break;
                case LogLevel::Warning:
                    Output::send<LogLevel::Warning>(STR("PalUIExt [{}] "), Name());
                    Output::send<LogLevel::Warning>(Fmt, std::forward<Args>(Fargs)...);
                    Output::send<LogLevel::Warning>(STR("\n"));
                    break;
                case LogLevel::Verbose:
                    Output::send<LogLevel::Verbose>(STR("PalUIExt [{}] "), Name());
                    Output::send<LogLevel::Verbose>(Fmt, std::forward<Args>(Fargs)...);
                    Output::send<LogLevel::Verbose>(STR("\n"));
                    break;
                default:
                    Output::send<LogLevel::Normal>(STR("PalUIExt [{}] "), Name());
                    Output::send<LogLevel::Normal>(Fmt, std::forward<Args>(Fargs)...);
                    Output::send<LogLevel::Normal>(STR("\n"));
                    break;
                }
            }
            catch (const std::exception&)
            {
                try { Output::send<LogLevel::Error>(STR("PalUIExt: malformed log format string\n")); }
                catch (...) {}
            }
            catch (...)
            {
            }
        }

        mutable std::unordered_set<StringType> m_log_once_keys;
        mutable std::unordered_map<StringType, std::chrono::steady_clock::time_point> m_log_throttle;
    };


    class ScopedHotPathTimer
    {
    public:
        ScopedHotPathTimer(const IUIFeature& Feature, const TCHAR* Label,
            int64_t ReportAboveMicros = 250)
            : m_feature(Feature), m_label(Label), m_threshold(ReportAboveMicros)
        {
            if constexpr (Static::kProfileHotPath)
            {
                m_start = std::chrono::steady_clock::now();
            }
        }

        ~ScopedHotPathTimer()
        {
            if constexpr (Static::kProfileHotPath)
            {
                const auto Micros = std::chrono::duration_cast<std::chrono::microseconds>(
                    std::chrono::steady_clock::now() - m_start).count();

                if (Micros >= m_threshold)
                {
                    m_feature.SendLogThrottled(m_label, 1000, LogLevel::Warning,
                        STR("slow path: {} took {}us"), m_label, Micros);
                }
            }
        }

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

    private:
        const IUIFeature& m_feature;
        const TCHAR* m_label;
        int64_t m_threshold;
        std::chrono::steady_clock::time_point m_start{};
    };
}