// Copyright 2022 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.

#include "sharing/nearby_file_handler.h"

#include <stdint.h>
#include <functional>
#include <memory>
#include <optional>
#include <utility>
#include <vector>

#include "absl/functional/any_invocable.h"
#include "absl/time/clock.h"
#include "absl/time/time.h"
#include "absl/types/span.h"
#include "internal/base/file_path.h"
#include "internal/base/files.h"
#include "internal/platform/task_runner.h"
#include "internal/platform/task_runner_impl.h"
#include "sharing/internal/api/sharing_platform.h"
#include "sharing/internal/public/logging.h"

namespace nearby {
namespace sharing {
namespace {

using ::nearby::sharing::api::SharingPlatform;

}  // namespace

NearbyFileHandler::NearbyFileHandler(SharingPlatform& platform,
                                     std::unique_ptr<TaskRunner> runner)
    : platform_(platform) {
  if (runner) {
    sequenced_task_runner_ = std::move(runner);
  } else {
    sequenced_task_runner_ = std::make_unique<TaskRunnerImpl>(1);
  }
}

NearbyFileHandler::~NearbyFileHandler() = default;

void NearbyFileHandler::DeleteFilesFromDisk(
    std::vector<FilePath> file_paths, DeleteFilesFromDiskCallback callback) {
  sequenced_task_runner_->PostTask([callback = std::move(callback),
                                    file_paths = std::move(file_paths)]() {
    // wait 1 second to make the file being released from another process.
    absl::SleepFor(absl::Seconds(1));
    for (const auto& file_path : file_paths) {
      if (!Files::FileExists(file_path)) {
        continue;
      }
      if (Files::RemoveFile(file_path)) {
        VLOG(1) << __func__
                << ": Removed partial file. File=" << file_path.ToString();
      } else {
        // Try once more after 3 seconds.
        absl::SleepFor(absl::Seconds(3));
        if (Files::RemoveFile(file_path)) {
          VLOG(1) << __func__
                  << ": Removed partial file after additional delay. File="
                  << file_path.ToString();
        } else {
          LOG(ERROR) << __func__
                     << "Can't remove file: " << file_path.ToString();
        }
      }
    }
    callback();
  });
}

void NearbyFileHandler::UpdateFilesOriginMetadata(
    std::vector<FilePath> file_paths,
    absl::AnyInvocable<void(bool success)> callback) {
  sequenced_task_runner_->PostTask(
      [this, callback = std::move(callback),
       file_paths = std::move(file_paths)]() mutable {
        std::move(callback)(platform_.UpdateFileOriginMetadata(file_paths));
      });
}

}  // namespace sharing
}  // namespace nearby