src/platform/nrfconnect/wifi/NrfWiFiDriver.h

/*
 *
 *    Copyright (c) 2022 Project CHIP Authors
 *
 *    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.
 */

#pragma once
#include <platform/NetworkCommissioning.h>

namespace chip {
namespace DeviceLayer {
namespace NetworkCommissioning {

constexpr uint8_t kMaxWiFiNetworks                  = 1;
constexpr uint8_t kWiFiScanNetworksTimeOutSeconds   = 10;
constexpr uint8_t kWiFiConnectNetworkTimeoutSeconds = 120;

class NrfWiFiScanResponseIterator : public Iterator<WiFiScanResponse>
{
public:
    size_t Count() override { return mResultCount; }
    bool Next(WiFiScanResponse & item) override;
    void Release() override;
    void Add(const WiFiScanResponse & result);

private:
    size_t mResultId            = 0;
    size_t mResultCount         = 0;
    WiFiScanResponse * mResults = nullptr;
};

class NrfWiFiDriver final : public WiFiDriver
{
public:
    // Define non-volatile storage keys for SSID and password.
    // The naming convention is aligned with DefaultStorageKeyAllocator class.
    static constexpr const char * kSsidKey = "g/wi/s";
    static constexpr const char * kPassKey = "g/wi/p";

    class WiFiNetworkIterator final : public NetworkIterator
    {
    public:
        WiFiNetworkIterator(NrfWiFiDriver * aDriver) : mDriver(aDriver) {}
        size_t Count() override;
        bool Next(Network & item) override;
        void Release() override { delete this; }
        ~WiFiNetworkIterator() = default;

    private:
        NrfWiFiDriver * mDriver;
        bool mExhausted{ false };
    };

    struct WiFiNetwork
    {
        uint8_t ssid[DeviceLayer::Internal::kMaxWiFiSSIDLength];
        size_t ssidLen = 0;
        uint8_t pass[DeviceLayer::Internal::kMaxWiFiKeyLength];
        size_t passLen = 0;

        bool IsConfigured() const { return ssidLen > 0; }
        ByteSpan GetSsidSpan() const { return ByteSpan(ssid, ssidLen); }
        ByteSpan GetPassSpan() const { return ByteSpan(pass, passLen); }
        void Clear() { ssidLen = 0; }
    };

    // BaseDriver
    NetworkIterator * GetNetworks() override { return new WiFiNetworkIterator(this); }
    CHIP_ERROR Init(NetworkStatusChangeCallback * networkStatusChangeCallback) override;
    void Shutdown() override;

    // WirelessDriver
    uint8_t GetMaxNetworks() override { return kMaxWiFiNetworks; }
    uint8_t GetScanNetworkTimeoutSeconds() override { return kWiFiScanNetworksTimeOutSeconds; }
    uint8_t GetConnectNetworkTimeoutSeconds() override { return kWiFiConnectNetworkTimeoutSeconds; }

    CHIP_ERROR CommitConfiguration() override;
    CHIP_ERROR RevertConfiguration() override;

    Status RemoveNetwork(ByteSpan networkId, MutableCharSpan & outDebugText, uint8_t & outNetworkIndex) override;
    Status ReorderNetwork(ByteSpan networkId, uint8_t index, MutableCharSpan & outDebugText) override;
    void ConnectNetwork(ByteSpan networkId, ConnectCallback * callback) override;

    // WiFiDriver
    Status AddOrUpdateNetwork(ByteSpan ssid, ByteSpan credentials, MutableCharSpan & outDebugText,
                              uint8_t & outNetworkIndex) override;
    void ScanNetworks(ByteSpan ssid, ScanCallback * callback) override;

    static NrfWiFiDriver & Instance()
    {
        static NrfWiFiDriver sInstance;
        return sInstance;
    }

    void OnConnectWiFiNetwork();
    void OnConnectWiFiNetworkFailed();
    void OnNetworkStatusChanged(Status status);
    void OnScanWiFiNetworkDone(int status, WiFiScanResponse * result);

private:
    void LoadFromStorage();

    ConnectCallback * mpConnectCallback{ nullptr };
    NetworkStatusChangeCallback * mpNetworkStatusChangeCallback{ nullptr };
    WiFiNetwork mStagingNetwork;
    NrfWiFiScanResponseIterator mScanResponseIterator;
    ScanCallback * mScanCallback{ nullptr };
};

} // namespace NetworkCommissioning
} // namespace DeviceLayer
} // namespace chip