/*
 * Copyright 2020 The Android Open Source Project
 *
 * 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.
 */

#include "storage/storage_module.h"

#include <bluetooth/log.h>
#include <com_android_bluetooth_flags.h>

#include <chrono>
#include <ctime>
#include <iomanip>
#include <memory>
#include <utility>

#include "common/bind.h"
#include "metrics/counter_metrics.h"
#include "os/alarm.h"
#include "os/files.h"
#include "os/handler.h"
#include "os/parameter_provider.h"
#include "os/system_properties.h"
#include "storage/config_cache.h"
#include "storage/config_keys.h"
#include "storage/legacy_config_file.h"
#include "storage/mutation.h"

namespace bluetooth {
namespace storage {

using os::Alarm;
using os::Handler;

static const std::string kFactoryResetProperty = "persist.bluetooth.factoryreset";

static const size_t kDefaultTempDeviceCapacity = 10000;
// Save config whenever there is a change, but delay it by this value so that burst config change
// won't overwhelm disk
static const std::chrono::milliseconds kDefaultConfigSaveDelay = std::chrono::milliseconds(3000);
// Writing a config to disk takes a minimum 10 ms on a decent x86_64 machine
// The config saving delay must be bigger than this value to avoid overwhelming the disk
static const std::chrono::milliseconds kMinConfigSaveDelay = std::chrono::milliseconds(20);

const int kConfigFileComparePass = 1;
const std::string kConfigFilePrefix = "bt_config-origin";
const std::string kConfigFileHash = "hash";

const std::string StorageModule::kInfoSection = BTIF_STORAGE_SECTION_INFO;
const std::string StorageModule::kTimeCreatedProperty = "TimeCreated";
const std::string StorageModule::kTimeCreatedFormat = "%Y-%m-%d %H:%M:%S";

const std::string StorageModule::kAdapterSection = BTIF_STORAGE_SECTION_ADAPTER;

StorageModule::StorageModule(std::string config_file_path,
                             std::chrono::milliseconds config_save_delay,
                             size_t temp_devices_capacity, bool is_restricted_mode,
                             bool is_single_user_mode)
    : config_file_path_(std::move(config_file_path)),
      config_save_delay_(config_save_delay),
      temp_devices_capacity_(temp_devices_capacity),
      is_restricted_mode_(is_restricted_mode),
      is_single_user_mode_(is_single_user_mode) {
  log::assert_that(config_save_delay > kMinConfigSaveDelay,
                   "Config save delay of {} ms is not enough, must be at least {} ms to avoid "
                   "overwhelming the "
                   "disk",
                   config_save_delay_.count(), kMinConfigSaveDelay.count());
}

StorageModule::~StorageModule() {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  pimpl_.reset();
}

const ModuleFactory StorageModule::Factory = ModuleFactory([]() {
  return new StorageModule(os::ParameterProvider::ConfigFilePath(), kDefaultConfigSaveDelay,
                           kDefaultTempDeviceCapacity, false, false);
});

struct StorageModule::impl {
  explicit impl(Handler* handler, ConfigCache cache, size_t in_memory_cache_size_limit)
      : config_save_alarm_(handler),
        cache_(std::move(cache)),
        memory_only_cache_(in_memory_cache_size_limit, {}) {}
  Alarm config_save_alarm_;
  ConfigCache cache_;
  ConfigCache memory_only_cache_;
  bool has_pending_config_save_ = false;
};

Mutation StorageModule::Modify() {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return Mutation(&pimpl_->cache_, &pimpl_->memory_only_cache_);
}

void StorageModule::SaveDelayed() {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  if (pimpl_->has_pending_config_save_) {
    return;
  }
  pimpl_->config_save_alarm_.Schedule(
          common::BindOnce(&StorageModule::SaveImmediately, common::Unretained(this)),
          config_save_delay_);
  pimpl_->has_pending_config_save_ = true;
}

void StorageModule::SaveImmediately() {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  if (pimpl_->has_pending_config_save_) {
    pimpl_->config_save_alarm_.Cancel();
    pimpl_->has_pending_config_save_ = false;
  }
#ifndef TARGET_FLOSS
  log::assert_that(
          LegacyConfigFile::FromPath(config_file_path_).Write(pimpl_->cache_),
          "assert failed: LegacyConfigFile::FromPath(config_file_path_).Write(pimpl_->cache_)");
#else
  if (!LegacyConfigFile::FromPath(config_file_path_).Write(pimpl_->cache_)) {
    log::error("Unable to write config file to disk");
  }
#endif
  // save checksum if it is running in common criteria mode
  if (bluetooth::os::ParameterProvider::GetBtKeystoreInterface() != nullptr &&
      bluetooth::os::ParameterProvider::IsCommonCriteriaMode()) {
    bluetooth::os::ParameterProvider::GetBtKeystoreInterface()->set_encrypt_key_or_remove_key(
            kConfigFilePrefix, kConfigFileHash);
  }
}

void StorageModule::Clear() {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  pimpl_->cache_.Clear();
}

void StorageModule::ListDependencies(ModuleList* list) const {
  list->add<metrics::CounterMetrics>();
}

void StorageModule::Start() {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  if (os::GetSystemProperty(kFactoryResetProperty) == "true") {
    log::info("{} is true, delete config files", kFactoryResetProperty);
    LegacyConfigFile::FromPath(config_file_path_).Delete();
    os::SetSystemProperty(kFactoryResetProperty, "false");
  }
  if (!is_config_checksum_pass(kConfigFileComparePass)) {
    LegacyConfigFile::FromPath(config_file_path_).Delete();
  }
  auto config = LegacyConfigFile::FromPath(config_file_path_).Read(temp_devices_capacity_);
  bool save_needed = false;
  if (!config || !config->HasSection(kAdapterSection)) {
    log::warn("Failed to load config at {}; creating new empty ones", config_file_path_);
    config.emplace(temp_devices_capacity_, Device::kLinkKeyProperties);

    // Set config file creation timestamp
    std::stringstream ss;
    auto now = std::chrono::system_clock::now();
    auto now_time_t = std::chrono::system_clock::to_time_t(now);
    ss << std::put_time(std::localtime(&now_time_t), kTimeCreatedFormat.c_str());
    config->SetProperty(kInfoSection, kTimeCreatedProperty, ss.str());
    save_needed = true;
  }
  pimpl_ = std::make_unique<impl>(GetHandler(), std::move(config.value()), temp_devices_capacity_);
  pimpl_->cache_.SetPersistentConfigChangedCallback(
          [this] { this->CallOn(this, &StorageModule::SaveDelayed); });

  // Cleanup temporary pairings if we have left guest mode
  if (!com::android::bluetooth::flags::guest_mode_bond() && !is_restricted_mode_) {
    config->RemoveSectionWithProperty("Restricted");
  }

  config->FixDeviceTypeInconsistencies();
  if (bluetooth::os::ParameterProvider::GetBtKeystoreInterface() != nullptr) {
    bluetooth::os::ParameterProvider::GetBtKeystoreInterface()
            ->ConvertEncryptOrDecryptKeyIfNeeded();
  }

  if (save_needed) {
    SaveDelayed();
  }
}

void StorageModule::Stop() {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  if (pimpl_->has_pending_config_save_) {
    // Save pending changes before stopping the module.
    SaveImmediately();
  }
  if (bluetooth::os::ParameterProvider::GetBtKeystoreInterface() != nullptr) {
    bluetooth::os::ParameterProvider::GetBtKeystoreInterface()->clear_map();
  }
  pimpl_.reset();
}

std::string StorageModule::ToString() const { return "Storage Module"; }

Device StorageModule::GetDeviceByLegacyKey(hci::Address legacy_key_address) {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return Device(&pimpl_->cache_, &pimpl_->memory_only_cache_, std::move(legacy_key_address),
                Device::ConfigKeyAddressType::LEGACY_KEY_ADDRESS);
}

Device StorageModule::GetDeviceByClassicMacAddress(hci::Address classic_address) {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return Device(&pimpl_->cache_, &pimpl_->memory_only_cache_, std::move(classic_address),
                Device::ConfigKeyAddressType::CLASSIC_ADDRESS);
}

Device StorageModule::GetDeviceByLeIdentityAddress(hci::Address le_identity_address) {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return Device(&pimpl_->cache_, &pimpl_->memory_only_cache_, std::move(le_identity_address),
                Device::ConfigKeyAddressType::LE_IDENTITY_ADDRESS);
}

std::vector<Device> StorageModule::GetBondedDevices() {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  auto persistent_sections = pimpl_->cache_.GetPersistentSections();
  std::vector<Device> result;
  result.reserve(persistent_sections.size());
  for (const auto& section : persistent_sections) {
    result.emplace_back(&pimpl_->cache_, &pimpl_->memory_only_cache_, section);
  }
  return result;
}

bool StorageModule::is_config_checksum_pass(int check_bit) {
  return (os::ParameterProvider::GetCommonCriteriaConfigCompareResult() & check_bit) == check_bit;
}

bool StorageModule::HasSection(const std::string& section) const {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return pimpl_->cache_.HasSection(section);
}

bool StorageModule::HasProperty(const std::string& section, const std::string& property) const {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return pimpl_->cache_.HasProperty(section, property);
}

std::optional<std::string> StorageModule::GetProperty(const std::string& section,
                                                      const std::string& property) const {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return pimpl_->cache_.GetProperty(section, property);
}

void StorageModule::SetProperty(std::string section, std::string property, std::string value) {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  pimpl_->cache_.SetProperty(section, property, value);
}

std::vector<std::string> StorageModule::GetPersistentSections() const {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return pimpl_->cache_.GetPersistentSections();
}

void StorageModule::RemoveSection(const std::string& section) {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  pimpl_->cache_.RemoveSection(section);
}

bool StorageModule::RemoveProperty(const std::string& section, const std::string& property) {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return pimpl_->cache_.RemoveProperty(section, property);
}

void StorageModule::ConvertEncryptOrDecryptKeyIfNeeded() {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  pimpl_->cache_.ConvertEncryptOrDecryptKeyIfNeeded();
}

void StorageModule::RemoveSectionWithProperty(const std::string& property) {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return pimpl_->cache_.RemoveSectionWithProperty(property);
}

void StorageModule::SetBool(const std::string& section, const std::string& property, bool value) {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  ConfigCacheHelper::FromConfigCache(pimpl_->cache_).SetBool(section, property, value);
}

std::optional<bool> StorageModule::GetBool(const std::string& section,
                                           const std::string& property) const {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return ConfigCacheHelper::FromConfigCache(pimpl_->cache_).GetBool(section, property);
}

void StorageModule::SetUint64(const std::string& section, const std::string& property,
                              uint64_t value) {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  ConfigCacheHelper::FromConfigCache(pimpl_->cache_).SetUint64(section, property, value);
}

std::optional<uint64_t> StorageModule::GetUint64(const std::string& section,
                                                 const std::string& property) const {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return ConfigCacheHelper::FromConfigCache(pimpl_->cache_).GetUint64(section, property);
}

void StorageModule::SetUint32(const std::string& section, const std::string& property,
                              uint32_t value) {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  ConfigCacheHelper::FromConfigCache(pimpl_->cache_).SetUint32(section, property, value);
}

std::optional<uint32_t> StorageModule::GetUint32(const std::string& section,
                                                 const std::string& property) const {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return ConfigCacheHelper::FromConfigCache(pimpl_->cache_).GetUint32(section, property);
}
void StorageModule::SetInt64(const std::string& section, const std::string& property,
                             int64_t value) {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  ConfigCacheHelper::FromConfigCache(pimpl_->cache_).SetInt64(section, property, value);
}
std::optional<int64_t> StorageModule::GetInt64(const std::string& section,
                                               const std::string& property) const {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return ConfigCacheHelper::FromConfigCache(pimpl_->cache_).GetInt64(section, property);
}

void StorageModule::SetInt(const std::string& section, const std::string& property, int value) {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  ConfigCacheHelper::FromConfigCache(pimpl_->cache_).SetInt(section, property, value);
}

std::optional<int> StorageModule::GetInt(const std::string& section,
                                         const std::string& property) const {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return ConfigCacheHelper::FromConfigCache(pimpl_->cache_).GetInt(section, property);
}

void StorageModule::SetBin(const std::string& section, const std::string& property,
                           const std::vector<uint8_t>& value) {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  ConfigCacheHelper::FromConfigCache(pimpl_->cache_).SetBin(section, property, value);
}

std::optional<std::vector<uint8_t>> StorageModule::GetBin(const std::string& section,
                                                          const std::string& property) const {
  std::lock_guard<std::recursive_mutex> lock(mutex_);
  return ConfigCacheHelper::FromConfigCache(pimpl_->cache_).GetBin(section, property);
}

}  // namespace storage
}  // namespace bluetooth