/*
 * Copyright (C) 2019 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 "common/libs/utils/archive.h"

#include <unistd.h>

#include <string>
#include <utility>
#include <vector>

#include <android-base/logging.h>
#include <android-base/strings.h>

#include "common/libs/utils/subprocess.h"

namespace cuttlefish {
namespace {

Result<std::vector<std::string>> ExtractHelper(
    std::vector<std::string>& files, const std::string& archive_filepath,
    const std::string& target_directory, const bool keep_archive) {
  CF_EXPECT(!files.empty(), "No files extracted from " << archive_filepath);

  auto it = files.begin();
  while (it != files.end()) {
    if (*it == "" || android::base::EndsWith(*it, "/")) {
      it = files.erase(it);
    } else {
      *it = target_directory + "/" + *it;
      it++;
    }
  }

  if (!keep_archive && unlink(archive_filepath.data()) != 0) {
    LOG(ERROR) << "Could not delete " << archive_filepath;
    files.push_back(archive_filepath);
  }

  return {files};
}

}  // namespace

Archive::Archive(const std::string& file) : file_(file) {}

Archive::~Archive() {}

std::vector<std::string> Archive::Contents() {
  Command bsdtar_cmd("/usr/bin/bsdtar");
  bsdtar_cmd.AddParameter("-tf");
  bsdtar_cmd.AddParameter(file_);
  std::string bsdtar_input, bsdtar_output;
  auto bsdtar_ret = RunWithManagedStdio(std::move(bsdtar_cmd), &bsdtar_input,
                                             &bsdtar_output, nullptr);
  if (bsdtar_ret != 0) {
    LOG(ERROR) << "`bsdtar -tf \"" << file_ << "\"` returned " << bsdtar_ret;
  }
  return bsdtar_ret == 0
      ? android::base::Split(bsdtar_output, "\n")
      : std::vector<std::string>();
}

bool Archive::ExtractAll(const std::string& target_directory) {
  return ExtractFiles({}, target_directory);
}

bool Archive::ExtractFiles(const std::vector<std::string>& to_extract,
                           const std::string& target_directory) {
  Command bsdtar_cmd("/usr/bin/bsdtar");
  bsdtar_cmd.AddParameter("-x");
  bsdtar_cmd.AddParameter("-v");
  bsdtar_cmd.AddParameter("-C");
  bsdtar_cmd.AddParameter(target_directory);
  bsdtar_cmd.AddParameter("-f");
  bsdtar_cmd.AddParameter(file_);
  bsdtar_cmd.AddParameter("-S");
  for (const auto& extract : to_extract) {
    bsdtar_cmd.AddParameter(extract);
  }
  bsdtar_cmd.RedirectStdIO(Subprocess::StdIOChannel::kStdOut,
                           Subprocess::StdIOChannel::kStdErr);
  auto bsdtar_ret = bsdtar_cmd.Start().Wait();
  if (bsdtar_ret != 0) {
    LOG(ERROR) << "bsdtar extraction on \"" << file_ << "\" returned "
               << bsdtar_ret;
  }
  return bsdtar_ret == 0;
}

std::string Archive::ExtractToMemory(const std::string& path) {
  Command bsdtar_cmd("/usr/bin/bsdtar");
  bsdtar_cmd.AddParameter("-xf");
  bsdtar_cmd.AddParameter(file_);
  bsdtar_cmd.AddParameter("-O");
  bsdtar_cmd.AddParameter(path);
  std::string stdout_str;
  auto ret =
      RunWithManagedStdio(std::move(bsdtar_cmd), nullptr, &stdout_str, nullptr);
  if (ret != 0) {
    LOG(ERROR) << "Could not extract \"" << path << "\" from \"" << file_
               << "\" to memory.";
    return "";
  }
  return stdout_str;
}

Result<std::vector<std::string>> ExtractImages(
    const std::string& archive_filepath, const std::string& target_directory,
    const std::vector<std::string>& images, const bool keep_archive) {
  Archive archive(archive_filepath);
  CF_EXPECT(archive.ExtractFiles(images, target_directory),
            "Could not extract images from \"" << archive_filepath << "\" to \""
                                               << target_directory << "\"");

  std::vector<std::string> files = images;
  return ExtractHelper(files, archive_filepath, target_directory, keep_archive);
}

Result<std::string> ExtractImage(const std::string& archive_filepath,
                                 const std::string& target_directory,
                                 const std::string& image,
                                 const bool keep_archive) {
  std::vector<std::string> result = CF_EXPECT(
      ExtractImages(archive_filepath, target_directory, {image}, keep_archive));
  return {result.front()};
}

Result<std::vector<std::string>> ExtractArchiveContents(
    const std::string& archive_filepath, const std::string& target_directory,
    const bool keep_archive) {
  Archive archive(archive_filepath);
  CF_EXPECT(archive.ExtractAll(target_directory),
            "Could not extract \"" << archive_filepath << "\" to \""
                                   << target_directory << "\"");

  std::vector<std::string> files = archive.Contents();
  return ExtractHelper(files, archive_filepath, target_directory, keep_archive);
}

} // namespace cuttlefish