/* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
   file Copyright.txt or https://cmake.org/licensing for details.  */
#include "cmCPackArchiveGenerator.h"

#include <cstring>
#include <map>
#include <ostream>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

#include "cmCPackComponentGroup.h"
#include "cmCPackGenerator.h"
#include "cmCPackLog.h"
#include "cmGeneratedFileStream.h"
#include "cmStringAlgorithms.h"
#include "cmSystemTools.h"
#include "cmValue.h"
#include "cmWorkingDirectory.h"

enum class DeduplicateStatus
{
  Skip,
  Add,
  Error
};

/**
 * @class cmCPackArchiveGenerator::Deduplicator
 * @brief A utility class for deduplicating files, folders, and symlinks.
 *
 * This class is responsible for identifying duplicate files, folders, and
 * symlinks when generating an archive. It keeps track of the paths that have
 * been processed and helps in deciding whether a new path should be added,
 * skipped, or flagged as an error.
 */
class cmCPackArchiveGenerator::Deduplicator
{
private:
  /**
   * @brief Compares a file with already processed files.
   *
   * @param path The path of the file to compare.
   * @param localTopLevel The top-level directory for the file.
   * @return DeduplicateStatus indicating whether to add, skip, or flag an
   * error for the file.
   */
  DeduplicateStatus CompareFile(const std::string& path,
                                const std::string& localTopLevel)
  {
    auto fileItr = this->Files.find(path);
    if (fileItr != this->Files.end()) {
      return cmSystemTools::FilesDiffer(path, fileItr->second)
        ? DeduplicateStatus::Error
        : DeduplicateStatus::Skip;
    }

    this->Files[path] = cmStrCat(localTopLevel, "/", path);
    return DeduplicateStatus::Add;
  }

  /**
   * @brief Compares a folder with already processed folders.
   *
   * @param path The path of the folder to compare.
   * @return DeduplicateStatus indicating whether to add or skip the folder.
   */
  DeduplicateStatus CompareFolder(const std::string& path)
  {
    if (this->Folders.find(path) != this->Folders.end()) {
      return DeduplicateStatus::Skip;
    }

    this->Folders.emplace(path);
    return DeduplicateStatus::Add;
  }

  /**
   * @brief Compares a symlink with already processed symlinks.
   *
   * @param path The path of the symlink to compare.
   * @return DeduplicateStatus indicating whether to add, skip, or flag an
   * error for the symlink.
   */
  DeduplicateStatus CompareSymlink(const std::string& path)
  {
    auto symlinkItr = this->Symlink.find(path);
    std::string symlinkValue;
    auto status = cmSystemTools::ReadSymlink(path, symlinkValue);
    if (!status.IsSuccess()) {
      return DeduplicateStatus::Error;
    }

    if (symlinkItr != this->Symlink.end()) {
      return symlinkValue == symlinkItr->second ? DeduplicateStatus::Skip
                                                : DeduplicateStatus::Error;
    }

    this->Symlink[path] = symlinkValue;
    return DeduplicateStatus::Add;
  }

public:
  /**
   * @brief Determines the deduplication status of a given path.
   *
   * This method identifies whether the given path is a file, folder, or
   * symlink and then delegates to the appropriate comparison method.
   *
   * @param path The path to check for deduplication.
   * @param localTopLevel The top-level directory for the path.
   * @return DeduplicateStatus indicating the action to take for the given
   * path.
   */
  DeduplicateStatus IsDeduplicate(const std::string& path,
                                  const std::string& localTopLevel)
  {
    DeduplicateStatus status;
    if (cmSystemTools::FileIsDirectory(path)) {
      status = this->CompareFolder(path);
    } else if (cmSystemTools::FileIsSymlink(path)) {
      status = this->CompareSymlink(path);
    } else {
      status = this->CompareFile(path, localTopLevel);
    }

    return status;
  }

private:
  std::unordered_map<std::string, std::string> Symlink;
  std::unordered_set<std::string> Folders;
  std::unordered_map<std::string, std::string> Files;
};

cmCPackGenerator* cmCPackArchiveGenerator::Create7ZGenerator()
{
  return new cmCPackArchiveGenerator(cmArchiveWrite::CompressNone, "7zip",
                                     ".7z");
}

cmCPackGenerator* cmCPackArchiveGenerator::CreateTBZ2Generator()
{
  return new cmCPackArchiveGenerator(cmArchiveWrite::CompressBZip2, "paxr",
                                     ".tar.bz2");
}

cmCPackGenerator* cmCPackArchiveGenerator::CreateTGZGenerator()
{
  return new cmCPackArchiveGenerator(cmArchiveWrite::CompressGZip, "paxr",
                                     ".tar.gz");
}

cmCPackGenerator* cmCPackArchiveGenerator::CreateTXZGenerator()
{
  return new cmCPackArchiveGenerator(cmArchiveWrite::CompressXZ, "paxr",
                                     ".tar.xz");
}

cmCPackGenerator* cmCPackArchiveGenerator::CreateTZGenerator()
{
  return new cmCPackArchiveGenerator(cmArchiveWrite::CompressCompress, "paxr",
                                     ".tar.Z");
}

cmCPackGenerator* cmCPackArchiveGenerator::CreateTZSTGenerator()
{
  return new cmCPackArchiveGenerator(cmArchiveWrite::CompressZstd, "paxr",
                                     ".tar.zst");
}

cmCPackGenerator* cmCPackArchiveGenerator::CreateZIPGenerator()
{
  return new cmCPackArchiveGenerator(cmArchiveWrite::CompressNone, "zip",
                                     ".zip");
}

cmCPackArchiveGenerator::cmCPackArchiveGenerator(
  cmArchiveWrite::Compress compress, std::string format, std::string extension)
  : Compress(compress)
  , ArchiveFormat(std::move(format))
  , OutputExtension(std::move(extension))
{
}

cmCPackArchiveGenerator::~cmCPackArchiveGenerator() = default;

std::string cmCPackArchiveGenerator::GetArchiveComponentFileName(
  const std::string& component, bool isGroupName)
{
  std::string componentUpper(cmSystemTools::UpperCase(component));
  std::string packageFileName;

  if (this->IsSet("CPACK_ARCHIVE_" + componentUpper + "_FILE_NAME")) {
    packageFileName +=
      *this->GetOption("CPACK_ARCHIVE_" + componentUpper + "_FILE_NAME");
  } else if (this->IsSet("CPACK_ARCHIVE_FILE_NAME")) {
    packageFileName += this->GetComponentPackageFileName(
      *this->GetOption("CPACK_ARCHIVE_FILE_NAME"), component, isGroupName);
  } else {
    packageFileName += this->GetComponentPackageFileName(
      *this->GetOption("CPACK_PACKAGE_FILE_NAME"), component, isGroupName);
  }

  packageFileName += this->GetOutputExtension();

  return packageFileName;
}

int cmCPackArchiveGenerator::InitializeInternal()
{
  this->SetOptionIfNotSet("CPACK_INCLUDE_TOPLEVEL_DIRECTORY", "1");
  cmValue newExtensionValue = this->GetOption("CPACK_ARCHIVE_FILE_EXTENSION");
  if (!newExtensionValue.IsEmpty()) {
    std::string newExtension = *newExtensionValue;
    if (!cmHasLiteralPrefix(newExtension, ".")) {
      newExtension = cmStrCat('.', newExtension);
    }
    cmCPackLogger(cmCPackLog::LOG_DEBUG,
                  "Using user-provided file extension "
                    << newExtension << " instead of the default "
                    << this->OutputExtension << std::endl);
    this->OutputExtension = std::move(newExtension);
  }
  return this->Superclass::InitializeInternal();
}

int cmCPackArchiveGenerator::addOneComponentToArchive(
  cmArchiveWrite& archive, cmCPackComponent* component,
  Deduplicator* deduplicator)
{
  cmCPackLogger(cmCPackLog::LOG_VERBOSE,
                "   - packaging component: " << component->Name << std::endl);
  // Add the files of this component to the archive
  std::string localToplevel(this->GetOption("CPACK_TEMPORARY_DIRECTORY"));
  localToplevel += "/" + this->GetSanitizedDirOrFileName(component->Name);
  // Change to local toplevel
  cmWorkingDirectory workdir(localToplevel);
  if (workdir.Failed()) {
    cmCPackLogger(cmCPackLog::LOG_ERROR,
                  "Failed to change working directory to "
                    << localToplevel << " : "
                    << std::strerror(workdir.GetLastResult()) << std::endl);
    return 0;
  }
  std::string filePrefix;
  if (this->IsOn("CPACK_COMPONENT_INCLUDE_TOPLEVEL_DIRECTORY")) {
    filePrefix = cmStrCat(this->GetOption("CPACK_PACKAGE_FILE_NAME"), '/');
  }
  cmValue installPrefix = this->GetOption("CPACK_PACKAGING_INSTALL_PREFIX");
  if (installPrefix && installPrefix->size() > 1 &&
      (*installPrefix)[0] == '/') {
    // add to file prefix and remove the leading '/'
    filePrefix += installPrefix->substr(1);
    filePrefix += "/";
  }
  for (std::string const& file : component->Files) {
    std::string rp = filePrefix + file;

    DeduplicateStatus status = DeduplicateStatus::Add;
    if (deduplicator) {
      status = deduplicator->IsDeduplicate(rp, localToplevel);
    }

    if (!deduplicator || status == DeduplicateStatus::Add) {
      cmCPackLogger(cmCPackLog::LOG_DEBUG, "Adding file: " << rp << std::endl);
      archive.Add(rp, 0, nullptr, false);
    } else if (status == DeduplicateStatus::Error) {
      cmCPackLogger(cmCPackLog::LOG_ERROR,
                    "ERROR The data in files with the "
                    "same filename is different.");
      return 0;
    } else {
      cmCPackLogger(cmCPackLog::LOG_DEBUG,
                    "Passing file: " << rp << std::endl);
    }

    if (!archive) {
      cmCPackLogger(cmCPackLog::LOG_ERROR,
                    "ERROR while packaging files: " << archive.GetError()
                                                    << std::endl);
      return 0;
    }
  }
  return 1;
}

/*
 * The macro will open/create a file 'filename'
 * an declare and open the associated
 * cmArchiveWrite 'archive' object.
 */
#define DECLARE_AND_OPEN_ARCHIVE(filename, archive)                           \
  cmGeneratedFileStream gf;                                                   \
  gf.Open((filename), false, true);                                           \
  if (!GenerateHeader(&gf)) {                                                 \
    cmCPackLogger(cmCPackLog::LOG_ERROR,                                      \
                  "Problem to generate Header for archive <"                  \
                    << (filename) << ">." << std::endl);                      \
    return 0;                                                                 \
  }                                                                           \
  cmArchiveWrite archive(gf, this->Compress, this->ArchiveFormat, 0,          \
                         this->GetThreadCount());                             \
  do {                                                                        \
    if (!archive.Open()) {                                                    \
      cmCPackLogger(cmCPackLog::LOG_ERROR,                                    \
                    "Problem to open archive <"                               \
                      << (filename) << ">, ERROR = " << (archive).GetError()  \
                      << std::endl);                                          \
      return 0;                                                               \
    }                                                                         \
    if (!(archive)) {                                                         \
      cmCPackLogger(cmCPackLog::LOG_ERROR,                                    \
                    "Problem to create archive <"                             \
                      << (filename) << ">, ERROR = " << (archive).GetError()  \
                      << std::endl);                                          \
      return 0;                                                               \
    }                                                                         \
  } while (false)

int cmCPackArchiveGenerator::PackageComponents(bool ignoreGroup)
{
  this->packageFileNames.clear();
  // The default behavior is to have one package by component group
  // unless CPACK_COMPONENTS_IGNORE_GROUP is specified.
  if (!ignoreGroup) {
    for (auto const& compG : this->ComponentGroups) {
      cmCPackLogger(cmCPackLog::LOG_VERBOSE,
                    "Packaging component group: " << compG.first << std::endl);
      // Begin the archive for this group
      std::string packageFileName = std::string(this->toplevel) + "/" +
        this->GetArchiveComponentFileName(compG.first, true);

      Deduplicator deduplicator;

      // open a block in order to automatically close archive
      // at the end of the block
      {
        DECLARE_AND_OPEN_ARCHIVE(packageFileName, archive);
        // now iterate over the component of this group
        for (cmCPackComponent* comp : (compG.second).Components) {
          // Add the files of this component to the archive
          this->addOneComponentToArchive(archive, comp, &deduplicator);
        }
      }
      // add the generated package to package file names list
      this->packageFileNames.push_back(std::move(packageFileName));
    }
    // Handle Orphan components (components not belonging to any groups)
    for (auto& comp : this->Components) {
      // Does the component belong to a group?
      if (!comp.second.Group) {
        cmCPackLogger(
          cmCPackLog::LOG_VERBOSE,
          "Component <"
            << comp.second.Name
            << "> does not belong to any group, package it separately."
            << std::endl);
        std::string packageFileName = std::string(this->toplevel);
        packageFileName +=
          "/" + this->GetArchiveComponentFileName(comp.first, false);

        {
          DECLARE_AND_OPEN_ARCHIVE(packageFileName, archive);
          // Add the files of this component to the archive
          this->addOneComponentToArchive(archive, &(comp.second), nullptr);
        }
        // add the generated package to package file names list
        this->packageFileNames.push_back(std::move(packageFileName));
      }
    }
  }
  // CPACK_COMPONENTS_IGNORE_GROUPS is set
  // We build 1 package per component
  else {
    for (auto& comp : this->Components) {
      std::string packageFileName = std::string(this->toplevel);
      packageFileName +=
        "/" + this->GetArchiveComponentFileName(comp.first, false);

      {
        DECLARE_AND_OPEN_ARCHIVE(packageFileName, archive);
        // Add the files of this component to the archive
        this->addOneComponentToArchive(archive, &(comp.second), nullptr);
      }
      // add the generated package to package file names list
      this->packageFileNames.push_back(std::move(packageFileName));
    }
  }
  return 1;
}

int cmCPackArchiveGenerator::PackageComponentsAllInOne()
{
  // reset the package file names
  this->packageFileNames.clear();
  this->packageFileNames.emplace_back(this->toplevel);
  this->packageFileNames[0] += "/";

  if (this->IsSet("CPACK_ARCHIVE_FILE_NAME")) {
    this->packageFileNames[0] += *this->GetOption("CPACK_ARCHIVE_FILE_NAME");
  } else {
    this->packageFileNames[0] += *this->GetOption("CPACK_PACKAGE_FILE_NAME");
  }

  this->packageFileNames[0] += this->GetOutputExtension();

  cmCPackLogger(cmCPackLog::LOG_VERBOSE,
                "Packaging all groups in one package..."
                "(CPACK_COMPONENTS_ALL_GROUPS_IN_ONE_PACKAGE is set)"
                  << std::endl);
  DECLARE_AND_OPEN_ARCHIVE(packageFileNames[0], archive);

  Deduplicator deduplicator;

  // The ALL COMPONENTS in ONE package case
  for (auto& comp : this->Components) {
    // Add the files of this component to the archive
    this->addOneComponentToArchive(archive, &(comp.second), &deduplicator);
  }

  // archive goes out of scope so it will finalized and closed.
  return 1;
}

int cmCPackArchiveGenerator::PackageFiles()
{
  cmCPackLogger(cmCPackLog::LOG_DEBUG,
                "Toplevel: " << this->toplevel << std::endl);

  if (this->WantsComponentInstallation()) {
    // CASE 1 : COMPONENT ALL-IN-ONE package
    // If ALL COMPONENTS in ONE package has been requested
    // then the package file is unique and should be open here.
    if (this->componentPackageMethod == ONE_PACKAGE) {
      return this->PackageComponentsAllInOne();
    }
    // CASE 2 : COMPONENT CLASSICAL package(s) (i.e. not all-in-one)
    // There will be 1 package for each component group
    // however one may require to ignore component group and
    // in this case you'll get 1 package for each component.
    return this->PackageComponents(this->componentPackageMethod ==
                                   ONE_PACKAGE_PER_COMPONENT);
  }

  // CASE 3 : NON COMPONENT package.
  DECLARE_AND_OPEN_ARCHIVE(packageFileNames[0], archive);
  cmWorkingDirectory workdir(this->toplevel);
  if (workdir.Failed()) {
    cmCPackLogger(cmCPackLog::LOG_ERROR,
                  "Failed to change working directory to "
                    << this->toplevel << " : "
                    << std::strerror(workdir.GetLastResult()) << std::endl);
    return 0;
  }
  for (std::string const& file : this->files) {
    // Get the relative path to the file
    std::string rp = cmSystemTools::RelativePath(this->toplevel, file);
    archive.Add(rp, 0, nullptr, false);
    if (!archive) {
      cmCPackLogger(cmCPackLog::LOG_ERROR,
                    "Problem while adding file <"
                      << file << "> to archive <" << this->packageFileNames[0]
                      << ">, ERROR = " << archive.GetError() << std::endl);
      return 0;
    }
  }
  // The destructor of cmArchiveWrite will close and finish the write
  return 1;
}

int cmCPackArchiveGenerator::GenerateHeader(std::ostream* /*unused*/)
{
  return 1;
}

bool cmCPackArchiveGenerator::SupportsComponentInstallation() const
{
  // The Component installation support should only
  // be activated if explicitly requested by the user
  // (for backward compatibility reason)
  return this->IsOn("CPACK_ARCHIVE_COMPONENT_INSTALL");
}

int cmCPackArchiveGenerator::GetThreadCount() const
{
  int threads = 1;

  // CPACK_ARCHIVE_THREADS overrides CPACK_THREADS
  if (this->IsSet("CPACK_ARCHIVE_THREADS")) {
    threads = std::stoi(*this->GetOption("CPACK_ARCHIVE_THREADS"));
  } else if (this->IsSet("CPACK_THREADS")) {
    threads = std::stoi(*this->GetOption("CPACK_THREADS"));
  }

  return threads;
}