//
// Copyright © 2019 Arm Ltd. All rights reserved.
// SPDX-License-Identifier: MIT
//

#pragma once

#include <CommandHandlerRegistry.hpp>
#include <Packet.hpp>
#include <NetworkSockets.hpp>

#include <atomic>
#include <string>
#include <thread>

#include <TimelineDecoder.hpp>
#include <DirectoryCaptureCommandHandler.hpp>
#include <TimelineCaptureCommandHandler.hpp>
#include <TimelineDirectoryCaptureCommandHandler.hpp>
#include "PeriodicCounterCaptureCommandHandler.hpp"
#include "StreamMetadataCommandHandler.hpp"

#include "PacketVersionResolver.hpp"

namespace armnn
{

namespace gatordmock
{

enum class TargetEndianness
{
    BeWire,
    LeWire
};

enum class PacketDirection
{
    Sending,
    ReceivedHeader,
    ReceivedData
};

///  A class that implements a Mock Gatord server. It will listen on a specified Unix domain socket (UDS)
///  namespace for client connections. It will then allow opertaions to manage coutners while receiving counter data.
class GatordMockService
{
public:
    /// @param registry reference to a command handler registry.
    /// @param echoPackets if true the raw packets will be printed to stdout.
    GatordMockService(armnnUtils::Sockets::Socket clientConnection, bool echoPackets)
            : m_ClientConnection(clientConnection)
            , m_PacketsReceivedCount(0)
            , m_EchoPackets(echoPackets)
            , m_CloseReceivingThread(false)
            , m_PacketVersionResolver()
            , m_HandlerRegistry()
            , m_TimelineDecoder()
            , m_StreamMetadataCommandHandler(
                    0, 0, m_PacketVersionResolver.ResolvePacketVersion(0, 0).GetEncodedValue(), !echoPackets)
            , m_CounterCaptureCommandHandler(
                    0, 4, m_PacketVersionResolver.ResolvePacketVersion(0, 4).GetEncodedValue(), !echoPackets)
            , m_DirectoryCaptureCommandHandler(
                    0, 2, m_PacketVersionResolver.ResolvePacketVersion(0, 2).GetEncodedValue(), !echoPackets)
            , m_TimelineCaptureCommandHandler(
                    1, 1, m_PacketVersionResolver.ResolvePacketVersion(1, 1).GetEncodedValue(), m_TimelineDecoder)
            , m_TimelineDirectoryCaptureCommandHandler(
                    1, 0, m_PacketVersionResolver.ResolvePacketVersion(1, 0).GetEncodedValue(),
                    m_TimelineCaptureCommandHandler, !echoPackets)
    {
        m_TimelineDecoder.SetDefaultCallbacks();

        m_HandlerRegistry.RegisterFunctor(&m_StreamMetadataCommandHandler);
        m_HandlerRegistry.RegisterFunctor(&m_CounterCaptureCommandHandler);
        m_HandlerRegistry.RegisterFunctor(&m_DirectoryCaptureCommandHandler);
        m_HandlerRegistry.RegisterFunctor(&m_TimelineDirectoryCaptureCommandHandler);
        m_HandlerRegistry.RegisterFunctor(&m_TimelineCaptureCommandHandler);
    }

    ~GatordMockService()
    {
        // We have set SOCK_CLOEXEC on these sockets but we'll close them to be good citizens.
        armnnUtils::Sockets::Close(m_ClientConnection);
    }

    /// Establish the Unix domain socket and set it to listen for connections.
    /// @param udsNamespace the namespace (socket address) associated with the listener.
    /// @return true only if the socket has been correctly setup.
    static bool OpenListeningSocket(armnnUtils::Sockets::Socket listeningSocket,
                                    const std::string udsNamespace,
                                    const int numOfConnections = 1);

    /// Once the connection is open wait to receive the stream meta data packet from the client. Reading this
    /// packet differs from others as we need to determine endianness.
    /// @return true only if a valid stream met data packet has been received.
    bool WaitForStreamMetaData();

    /// Send a connection acknowledged packet back to the client.
    void SendConnectionAck();

    /// Send a request counter directory packet back to the client.
    void SendRequestCounterDir();

    /// Send a activate timeline packet back to the client.
    void SendActivateTimelinePacket();

    /// Send a deactivate timeline packet back to the client.
    void SendDeactivateTimelinePacket();

    /// Start the thread that will receive all packets and print them nicely to stdout.
    bool LaunchReceivingThread();

    /// Return the total number of periodic counter capture packets received since the receive thread started.
    /// @return number of periodic counter capture packets received.
    uint32_t GetPacketsReceivedCount()
    {
        return m_PacketsReceivedCount.load(std::memory_order_acquire);
    }

    /// This is a placeholder method to prevent main exiting. It can be removed once the
    /// command handling code is added.
    void WaitForReceivingThread();

    // @return true only if the receive thread is closed or closing.
    bool ReceiveThreadRunning()
    {
        return !m_CloseReceivingThread.load();
    }

    /// Send the counter list to ArmNN.
    void SendPeriodicCounterSelectionList(uint32_t period, std::vector<uint16_t> counters);

    /// Execute the WAIT command from the comamnd file.
    void WaitCommand(uint32_t timeout);

    uint32_t GetStreamMetadataVersion()
    {
        return m_StreamMetaDataVersion;
    }

    uint32_t GetStreamMetadataMaxDataLen()
    {
        return m_StreamMetaDataMaxDataLen;
    }

    uint32_t GetStreamMetadataPid()
    {
        return m_StreamMetaDataPid;
    }

    profiling::DirectoryCaptureCommandHandler& GetDirectoryCaptureCommandHandler()
    {
        return m_DirectoryCaptureCommandHandler;
    }

    timelinedecoder::TimelineDecoder& GetTimelineDecoder()
    {
        return m_TimelineDecoder;
    }

    timelinedecoder::TimelineDirectoryCaptureCommandHandler& GetTimelineDirectoryCaptureCommandHandler()
    {
        return m_TimelineDirectoryCaptureCommandHandler;
    }


private:
    void ReceiveLoop(GatordMockService& mockService);

    int MainLoop(armnn::profiling::CommandHandlerRegistry& registry, armnnUtils::Sockets::Socket m_ClientConnection);

    /// Block on the client connection until a complete packet has been received. This is a placeholder function to
    /// enable early testing of the tool.
    /// @return true if a valid packet has been received.
    armnn::profiling::Packet WaitForPacket(uint32_t timeoutMs);

    armnn::profiling::Packet ReceivePacket();

    bool SendPacket(uint32_t packetFamily, uint32_t packetId, const uint8_t* data, uint32_t dataLength);

    void EchoPacket(PacketDirection direction, uint8_t* packet, size_t lengthInBytes);

    bool ReadHeader(uint32_t headerAsWords[2]);

    bool ReadFromSocket(uint8_t* packetData, uint32_t expectedLength);

    uint32_t ToUint32(uint8_t* data, TargetEndianness endianness);

    void InsertU32(uint32_t value, uint8_t* data, TargetEndianness endianness);

    static const uint32_t PIPE_MAGIC = 0x45495434;

    TargetEndianness m_Endianness;
    uint32_t m_StreamMetaDataVersion;
    uint32_t m_StreamMetaDataMaxDataLen;
    uint32_t m_StreamMetaDataPid;

    armnnUtils::Sockets::Socket m_ClientConnection;
    std::atomic<uint32_t> m_PacketsReceivedCount;

    bool m_EchoPackets;
    std::thread m_ListeningThread;
    std::atomic<bool> m_CloseReceivingThread;

    profiling::PacketVersionResolver m_PacketVersionResolver;
    profiling::CommandHandlerRegistry m_HandlerRegistry;

    timelinedecoder::TimelineDecoder m_TimelineDecoder;

    gatordmock::StreamMetadataCommandHandler m_StreamMetadataCommandHandler;
    gatordmock::PeriodicCounterCaptureCommandHandler m_CounterCaptureCommandHandler;

    profiling::DirectoryCaptureCommandHandler m_DirectoryCaptureCommandHandler;

    timelinedecoder::TimelineCaptureCommandHandler m_TimelineCaptureCommandHandler;
    timelinedecoder::TimelineDirectoryCaptureCommandHandler m_TimelineDirectoryCaptureCommandHandler;
};
}    // namespace gatordmock

}    // namespace armnn