/*
 *
 *    Copyright (c) 2024 Project CHIP Authors
 *    All rights reserved.
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */

/**
 *    @file
 *      This file defines the Matter Connection object that maintains a Wi-Fi PAF connection.
 *
 */

#pragma once

#include <lib/core/CHIPCore.h>
#include <lib/support/DLLUtil.h>
#include <system/SystemPacketBuffer.h>
#include <transport/raw/Base.h>
#include <utility>

namespace chip {
namespace Transport {

class WiFiPAFLayer
{
public:
    WiFiPAFLayer() = default;
};
class WiFiPAFListenParameters;

/**
 * Implements a transport using Wi-Fi-PAF
 */
class DLL_EXPORT WiFiPAFBase : public Base
{
public:
    /**
     *  The State of the Wi-Fi-PAF connection
     *
     */
    enum class State
    {
        kNotReady    = 0, /**< State before initialization. */
        kInitialized = 1, /**< State after class is connected and ready. */
        kConnected   = 2, /**< Endpoint connected. */
    };
    WiFiPAFBase() = default;
    WiFiPAFBase(System::PacketBufferHandle * packetBuffers, size_t packetBuffersSize) :
        mPendingPackets(packetBuffers), mPendingPacketsSize(packetBuffersSize)
    {}
    ~WiFiPAFBase() override;

    /**
     * Initialize a Wi-Fi-PAF transport
     *
     * @param param        Wi-Fi-PAF configuration parameters for this transport
     */
    CHIP_ERROR Init(const WiFiPAFListenParameters & param);
    CHIP_ERROR SendMessage(const Transport::PeerAddress & address, System::PacketBufferHandle && msgBuf) override;
    bool CanSendToPeer(const Transport::PeerAddress & address) override
    {
        return (mState != State::kNotReady) && (address.GetTransportType() == Type::kWiFiPAF);
    }
    void OnWiFiPAFMessageReceived(System::PacketBufferHandle && buffer);
    void SetWiFiPAFState(State state) { mState = state; };
    State GetWiFiPAFState() { return mState; };

private:
    void ClearState();
    /**
     * Sends the specified message once a connection has been established.
     * @param msg - what buffer to send once a connection has been established.
     */
    CHIP_ERROR SendAfterConnect(System::PacketBufferHandle && msg);
    State mState = State::kNotReady;

    System::PacketBufferHandle * mPendingPackets;
    size_t mPendingPacketsSize;
};

template <size_t kPendingPacketSize>
class WiFiPAF : public WiFiPAFBase
{
public:
    WiFiPAF() : WiFiPAFBase(mPendingPackets, kPendingPacketSize) {}

private:
    System::PacketBufferHandle mPendingPackets[kPendingPacketSize];
};

/** Defines parameters for setting up the Wi-Fi PAF transport */
class WiFiPAFListenParameters
{
public:
    WiFiPAFListenParameters() = default;
    explicit WiFiPAFListenParameters(WiFiPAFBase * layer) : mWiFiPAF(layer) {}

private:
    WiFiPAFBase * mWiFiPAF;
};

} // namespace Transport
} // namespace chip