text: /*
   *
   *    Copyright (c) 2020-2022 Project CHIP Authors
   *    Copyright (c) 2019-2020 Google LLC.
   *    Copyright (c) 2018 Nest Labs, Inc.
   *    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
   *          Utilities for interacting with the the ESP32 "NVS" key-value store.
   */
  
  #pragma once
  
  #include <platform/internal/CHIPDeviceLayerInternal.h>
  
  #include <string.h>
  
  namespace chip {
  namespace DeviceLayer {
  namespace Internal {
  
  /**
   * Provides functions and definitions for accessing device configuration information on the ESP32.
   *
   * This class is designed to be mixed-in to concrete implementation classes as a means to
   * provide access to configuration information to generic base classes.
   */
  class ESP32Config
  {
  public:
      struct Key;
  
      // Maximum length of an NVS key name, as specified in the ESP-IDF documentation.
      static constexpr size_t kMaxConfigKeyNameLength = 15;
  
      // NVS namespaces used to store device configuration information.
      static const char kConfigNamespace_ChipFactory[];
      static const char kConfigNamespace_ChipConfig[];
      static const char kConfigNamespace_ChipCounters[];
  
      // Key definitions for well-known keys.
      static const Key kConfigKey_SerialNum;
      static const Key kConfigKey_UniqueId;
      static const Key kConfigKey_MfrDeviceId;
      static const Key kConfigKey_MfrDeviceCert;
      static const Key kConfigKey_MfrDeviceICACerts;
      static const Key kConfigKey_MfrDevicePrivateKey;
      static const Key kConfigKey_HardwareVersion;
      static const Key kConfigKey_ManufacturingDate;
      static const Key kConfigKey_SetupPinCode;
      static const Key kConfigKey_FabricId;
      static const Key kConfigKey_ServiceConfig;
      static const Key kConfigKey_PairedAccountId;
      static const Key kConfigKey_ServiceId;
      static const Key kConfigKey_FabricSecret;
      static const Key kConfigKey_GroupKeyIndex;
      static const Key kConfigKey_LastUsedEpochKeyId;
      static const Key kConfigKey_FailSafeArmed;
      static const Key kConfigKey_WiFiStationSecType;
      static const Key kConfigKey_SetupDiscriminator;
      static const Key kConfigKey_RegulatoryLocation;
      static const Key kConfigKey_CountryCode;
      static const Key kConfigKey_Breadcrumb;
      static const Key kConfigKey_Spake2pIterationCount;
      static const Key kConfigKey_Spake2pSalt;
      static const Key kConfigKey_Spake2pVerifier;
  
      // CHIP Counter keys
      static const Key kCounterKey_RebootCount;
      static const Key kCounterKey_UpTime;
      static const Key kCounterKey_TotalOperationalHours;
  
      static const char kGroupKeyNamePrefix[];
  
      // Config value accessors.
      static CHIP_ERROR ReadConfigValue(Key key, bool & val);
      static CHIP_ERROR ReadConfigValue(Key key, uint32_t & val);
      static CHIP_ERROR ReadConfigValue(Key key, uint64_t & val);
      static CHIP_ERROR ReadConfigValueStr(Key key, char * buf, size_t bufSize, size_t & outLen);
      static CHIP_ERROR ReadConfigValueBin(Key key, uint8_t * buf, size_t bufSize, size_t & outLen);
      static CHIP_ERROR WriteConfigValue(Key key, bool val);
      static CHIP_ERROR WriteConfigValue(Key key, uint32_t val);
      static CHIP_ERROR WriteConfigValue(Key key, uint64_t val);
      static CHIP_ERROR WriteConfigValueStr(Key key, const char * str);
      static CHIP_ERROR WriteConfigValueStr(Key key, const char * str, size_t strLen);
      static CHIP_ERROR WriteConfigValueBin(Key key, const uint8_t * data, size_t dataLen);
      static CHIP_ERROR ClearConfigValue(Key key);
      static bool ConfigValueExists(Key key);
  
      // NVS Namespace helper functions.
      static CHIP_ERROR EnsureNamespace(const char * ns);
      static CHIP_ERROR ClearNamespace(const char * ns);
  
      static void RunConfigUnitTest(void);
  };
  
  struct ESP32Config::Key
  {
      const char * Namespace;
      const char * Name;
  
      bool operator==(const Key & other) const;
  
      template <typename T, typename std::enable_if_t<std::is_convertible<T, const char *>::value, int> = 0>
      Key(const char * aNamespace, T aName) : Namespace(aNamespace), Name(aName)
      {}
  
      template <size_t N>
      Key(const char * aNamespace, const char (&aName)[N]) : Namespace(aNamespace), Name(aName)
      {
          // Note: N includes null-terminator.
          static_assert(N <= ESP32Config::kMaxConfigKeyNameLength + 1, "Key too long");
      }
  };
  
  inline bool ESP32Config::Key::operator==(const Key & other) const
  {
      return strcmp(Namespace, other.Namespace) == 0 && strcmp(Name, other.Name) == 0;
  }
  
  } // namespace Internal
  } // namespace DeviceLayer
  } // namespace chip
  