// Copyright 2020 Google LLC
//
// 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
//
//     https://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.

#ifndef PLATFORM_API_PLATFORM_H_
#define PLATFORM_API_PLATFORM_H_

#include <cstddef>
#include <cstdint>
#include <functional>
#include <memory>
#include <string>

#include "absl/status/statusor.h"
#include "absl/strings/string_view.h"
#include "internal/platform/implementation/app_lifecycle_monitor.h"
#include "internal/platform/implementation/atomic_boolean.h"
#include "internal/platform/implementation/atomic_reference.h"
#include "internal/platform/implementation/awdl.h"
#include "internal/platform/implementation/ble.h"
#include "internal/platform/implementation/bluetooth_adapter.h"
#include "internal/platform/implementation/bluetooth_classic.h"
#include "internal/platform/implementation/condition_variable.h"
#include "internal/platform/implementation/count_down_latch.h"
#include "internal/platform/implementation/credential_storage.h"
#include "internal/platform/implementation/device_info.h"
#include "internal/platform/implementation/http_loader.h"
#include "internal/platform/implementation/input_file.h"
#include "internal/platform/implementation/log_message.h"
#include "internal/platform/implementation/mutex.h"
#include "internal/platform/implementation/output_file.h"
#include "internal/platform/implementation/scheduled_executor.h"
#include "internal/platform/implementation/submittable_executor.h"
#include "internal/platform/implementation/timer.h"
#ifndef NO_WEBRTC
#include "internal/platform/implementation/webrtc.h"
#endif
#ifndef NEARBY_CHROMIUM
#include "internal/platform/implementation/preferences_manager.h"
#endif
#include "internal/platform/implementation/wifi.h"
#include "internal/platform/implementation/wifi_direct.h"
#include "internal/platform/implementation/wifi_hotspot.h"
#include "internal/platform/implementation/wifi_lan.h"
#include "internal/platform/os_name.h"
#include "internal/platform/payload_id.h"

namespace nearby {
namespace api {

// API rework notes:
// https://docs.google.com/spreadsheets/d/1erZNkX7pX8s5jWTHdxgjntxTMor3BGiY2H_fC_ldtoQ/edit#gid=381357998
class ImplementationPlatform {
 public:
  // General platform support:
  // - atomic variables (boolean, and any other copyable type)
  // - synchronization primitives:
  //   - mutex (regular, and recursive)
  //   - condition variable (must work with regular mutex only)
  //   - CountDownLatch : to ensure at least N threads are waiting.
  // - file I/O
  // - Logging
  static std::string GetCustomSavePath(const std::string& parent_folder,
                                       const std::string& file_name);

  static std::string GetDownloadPath(const std::string& parent_folder,
                                     const std::string& file_name);

  static std::string GetDownloadPath(const std::string& file_name);

  static std::string GetAppDataPath(const std::string& file_name);

  static OSName GetCurrentOS();

  // Atomics:
  // =======

  // Atomic boolean: special case. Uses native platform atomics.
  // Does not use locking.
  // Does not use dynamic memory allocations in operations.
  static std::unique_ptr<AtomicBoolean> CreateAtomicBoolean(bool initial_value);

  // Supports enums and integers up to 32-bit.
  // Does not use locking, if platform supports 32-bit atomics natively.
  // Does not use dynamic memory allocations in operations.
  static std::unique_ptr<AtomicUint32> CreateAtomicUint32(std::uint32_t value);

  static std::unique_ptr<CountDownLatch> CreateCountDownLatch(
      std::int32_t count);

#pragma push_macro("CreateMutex")
#undef CreateMutex
  static std::unique_ptr<Mutex> CreateMutex(Mutex::Mode mode);
#pragma pop_macro("CreateMutex")

  static std::unique_ptr<ConditionVariable> CreateConditionVariable(
      Mutex* mutex);

  static std::unique_ptr<InputFile> CreateInputFile(PayloadId);

  static std::unique_ptr<InputFile> CreateInputFile(const std::string&);

  static std::unique_ptr<OutputFile> CreateOutputFile(PayloadId);

  static std::unique_ptr<OutputFile> CreateOutputFile(const std::string&);

  static std::unique_ptr<LogMessage> CreateLogMessage(
      const char* file, int line, LogMessage::Severity severity);

  // Java-like Executors
  static std::unique_ptr<SubmittableExecutor> CreateSingleThreadExecutor();
  static std::unique_ptr<SubmittableExecutor> CreateMultiThreadExecutor(
      std::int32_t max_concurrency);
  static std::unique_ptr<ScheduledExecutor> CreateScheduledExecutor();

  // Protocol implementations, domain-specific support
  static std::unique_ptr<AwdlMedium> CreateAwdlMedium();
  static std::unique_ptr<BluetoothAdapter> CreateBluetoothAdapter();
  static std::unique_ptr<BluetoothClassicMedium> CreateBluetoothClassicMedium(
      BluetoothAdapter&);
  static std::unique_ptr<api::ble::BleMedium> CreateBleMedium(
      api::BluetoothAdapter&);
  static std::unique_ptr<api::CredentialStorage> CreateCredentialStorage();
  static std::unique_ptr<WifiMedium> CreateWifiMedium();
  static std::unique_ptr<WifiLanMedium> CreateWifiLanMedium();
  static std::unique_ptr<WifiHotspotMedium> CreateWifiHotspotMedium();
  static std::unique_ptr<WifiDirectMedium> CreateWifiDirectMedium();
  static std::unique_ptr<Timer> CreateTimer();
  static std::unique_ptr<DeviceInfo> CreateDeviceInfo();
#ifndef NO_WEBRTC
  static std::unique_ptr<WebRtcMedium> CreateWebRtcMedium();
#endif

#if defined(NEARBY_CHROMIUM)
  static std::unique_ptr<AppLifecycleMonitor> CreateAppLifecycleMonitor(
      std::function<void(AppLifecycleMonitor::AppLifecycleState)>
          state_updated_callback) {
    return nullptr;
  }
#else
  static std::unique_ptr<AppLifecycleMonitor> CreateAppLifecycleMonitor(
      std::function<void(AppLifecycleMonitor::AppLifecycleState)>
          state_updated_callback);
#endif

  // Gets HTTP response from remote server.
  //
  // @param request Webrequest
  //
  // @return returns absl::FailedPreconditionError if having platform error.
  //         return WebResponse if HTTP status code between 200 and 300.
  //         other cases will return absl Status in error.
  static absl::StatusOr<WebResponse> SendRequest(const WebRequest& request);

#if defined(NEARBY_CHROMIUM)
  static std::unique_ptr<nearby::api::PreferencesManager>
  CreatePreferencesManager(absl::string_view path) {
    return nullptr;
  }
#else
  static std::unique_ptr<nearby::api::PreferencesManager>
  CreatePreferencesManager(absl::string_view path);
#endif
};

}  // namespace api
}  // namespace nearby

#endif  // PLATFORM_API_PLATFORM_H_