text: import glob
  import logging
  import os
  import tarfile
  import zipfile
  
  from pathlib import Path
  from typing import TYPE_CHECKING
  from typing import Dict
  from typing import Iterator
  from typing import List
  from typing import Optional
  from typing import Union
  
  import pkginfo
  
  from poetry.core.factory import Factory
  from poetry.core.packages.dependency import Dependency
  from poetry.core.packages.package import Package
  from poetry.core.pyproject.toml import PyProjectTOML
  from poetry.core.utils.helpers import parse_requires
  from poetry.core.utils.helpers import temporary_directory
  from poetry.core.version.markers import InvalidMarker
  
  from poetry.utils.env import EnvCommandError
  from poetry.utils.env import ephemeral_environment
  from poetry.utils.setup_reader import SetupReader
  
  
  if TYPE_CHECKING:
      from poetry.core.packages.project_package import ProjectPackage
  
  
  logger = logging.getLogger(__name__)
  
  PEP517_META_BUILD = """\
  import pep517.build
  import pep517.meta
  
  path='{source}'
  system=pep517.build.compat_system(path)
  pep517.meta.build(source_dir=path, dest='{dest}', system=system)
  """
  
  PEP517_META_BUILD_DEPS = ["pep517===0.8.2", "toml==0.10.1"]
  
  
  class PackageInfoError(ValueError):
      def __init__(
          self, path: Union[Path, str], *reasons: Union[BaseException, str]
      ) -> None:
          reasons = (f"Unable to determine package info for path: {path!s}",) + reasons
          super().__init__("\n\n".join(str(msg).strip() for msg in reasons if msg))
  
  
  class PackageInfo:
      def __init__(
          self,
          name: Optional[str] = None,
          version: Optional[str] = None,
          summary: Optional[str] = None,
          platform: Optional[str] = None,
          requires_dist: Optional[List[str]] = None,
          requires_python: Optional[str] = None,
          files: Optional[List[Dict[str, str]]] = None,
          cache_version: Optional[str] = None,
      ):
          self.name = name
          self.version = version
          self.summary = summary
          self.platform = platform
          self.requires_dist = requires_dist
          self.requires_python = requires_python
          self.files = files or []
          self._cache_version = cache_version
          self._source_type = None
          self._source_url = None
          self._source_reference = None
  
      @property
      def cache_version(self) -> Optional[str]:
          return self._cache_version
  
      def update(self, other: "PackageInfo") -> "PackageInfo":
          self.name = other.name or self.name
          self.version = other.version or self.version
          self.summary = other.summary or self.summary
          self.platform = other.platform or self.platform
          self.requires_dist = other.requires_dist or self.requires_dist
          self.requires_python = other.requires_python or self.requires_python
          self.files = other.files or self.files
          self._cache_version = other.cache_version or self._cache_version
          return self
  
      def asdict(self) -> Dict[str, Optional[Union[str, List[str]]]]:
          """
          Helper method to convert package info into a dictionary used for caching.
          """
          return {
              "name": self.name,
              "version": self.version,
              "summary": self.summary,
              "platform": self.platform,
              "requires_dist": self.requires_dist,
              "requires_python": self.requires_python,
              "files": self.files,
              "_cache_version": self._cache_version,
          }
  
      @classmethod
      def load(cls, data: Dict[str, Optional[Union[str, List[str]]]]) -> "PackageInfo":
          """
          Helper method to load data from a dictionary produced by `PackageInfo.asdict()`.
  
          :param data: Data to load. This is expected to be a `dict` object output by `asdict()`.
          """
          cache_version = data.pop("_cache_version", None)
          return cls(cache_version=cache_version, **data)
  
      @classmethod
      def _log(cls, msg: str, level: str = "info") -> None:
          """Internal helper method to log information."""
          getattr(logger, level)(f"<debug>{cls.__name__}:</debug> {msg}")
  
      def to_package(
          self,
          name: Optional[str] = None,
          extras: Optional[List[str]] = None,
          root_dir: Optional[Path] = None,
      ) -> Package:
          """
          Create a new `poetry.core.packages.package.Package` instance using metadata from this instance.
  
          :param name: Name to use for the package, if not specified name from this instance is used.
          :param extras: Extras to activate for this package.
          :param root_dir:  Optional root directory to use for the package. If set, dependency strings
              will be parsed relative to this directory.
          """
          name = name or self.name
  
          if not self.version:
              # The version could not be determined, so we raise an error since it is mandatory.
              raise RuntimeError(f"Unable to retrieve the package version for {name}")
  
          package = Package(
              name=name,
              version=self.version,
              source_type=self._source_type,
              source_url=self._source_url,
              source_reference=self._source_reference,
          )
          package.description = self.summary
          package.root_dir = root_dir
          package.python_versions = self.requires_python or "*"
          package.files = self.files
  
          if root_dir or (self._source_type in {"directory"} and self._source_url):
              # this is a local poetry project, this means we can extract "richer" requirement information
              # eg: development requirements etc.
              poetry_package = self._get_poetry_package(path=root_dir or self._source_url)
              if poetry_package:
                  package.extras = poetry_package.extras
                  for dependency in poetry_package.requires:
                      package.add_dependency(dependency)
  
                  return package
  
          seen_requirements = set()
  
          for req in self.requires_dist or []:
              try:
                  # Attempt to parse the PEP-508 requirement string
                  dependency = Dependency.create_from_pep_508(req, relative_to=root_dir)
              except InvalidMarker:
                  # Invalid marker, We strip the markers hoping for the best
                  req = req.split(";")[0]
                  dependency = Dependency.create_from_pep_508(req, relative_to=root_dir)
              except ValueError:
                  # Likely unable to parse constraint so we skip it
                  self._log(
                      f"Invalid constraint ({req}) found in {package.name}-{package.version} dependencies, "
                      "skipping",
                      level="warning",
                  )
                  continue
  
              if dependency.in_extras:
                  # this dependency is required by an extra package
                  for extra in dependency.in_extras:
                      if extra not in package.extras:
                          # this is the first time we encounter this extra for this package
                          package.extras[extra] = []
  
                      package.extras[extra].append(dependency)
  
              req = dependency.to_pep_508(with_extras=True)
  
              if req not in seen_requirements:
                  package.add_dependency(dependency)
                  seen_requirements.add(req)
  
          return package
  
      @classmethod
      def _from_distribution(
          cls, dist: Union[pkginfo.BDist, pkginfo.SDist, pkginfo.Wheel]
      ) -> "PackageInfo":
          """
          Helper method to parse package information from a `pkginfo.Distribution` instance.
  
          :param dist: The distribution instance to parse information from.
          """
          requirements = None
  
          if dist.requires_dist:
              requirements = list(dist.requires_dist)
          else:
              requires = Path(dist.filename) / "requires.txt"
              if requires.exists():
                  with requires.open(encoding="utf-8") as f:
                      requirements = parse_requires(f.read())
  
          info = cls(
              name=dist.name,
              version=dist.version,
              summary=dist.summary,
              platform=dist.supported_platforms,
              requires_dist=requirements,
              requires_python=dist.requires_python,
          )
  
          info._source_type = "file"
          info._source_url = Path(dist.filename).resolve().as_posix()
  
          return info
  
      @classmethod
      def _from_sdist_file(cls, path: Path) -> "PackageInfo":
          """
          Helper method to parse package information from an sdist file. We attempt to first inspect the
          file using `pkginfo.SDist`. If this does not provide us with package requirements, we extract the
          source and handle it as a directory.
  
          :param path: The sdist file to parse information from.
          """
          info = None
  
          try:
              info = cls._from_distribution(pkginfo.SDist(str(path)))
          except ValueError:
              # Unable to determine dependencies
              # We pass and go deeper
              pass
          else:
              if info.requires_dist is not None:
                  # we successfully retrieved dependencies from sdist metadata
                  return info
  
          # Still not dependencies found
          # So, we unpack and introspect
          suffix = path.suffix
  
          if suffix == ".zip":
              context = zipfile.ZipFile
          else:
              if suffix == ".bz2":
                  suffixes = path.suffixes
                  if len(suffixes) > 1 and suffixes[-2] == ".tar":
                      suffix = ".tar.bz2"
              else:
                  suffix = ".tar.gz"
  
              context = tarfile.open
  
          with temporary_directory() as tmp:
              tmp = Path(tmp)
              with context(path.as_posix()) as archive:
                  archive.extractall(tmp.as_posix())
  
              # a little bit of guess work to determine the directory we care about
              elements = list(tmp.glob("*"))
  
              if len(elements) == 1 and elements[0].is_dir():
                  sdist_dir = elements[0]
              else:
                  sdist_dir = tmp / path.name.rstrip(suffix)
                  if not sdist_dir.is_dir():
                      sdist_dir = tmp
  
              # now this is an unpacked directory we know how to deal with
              new_info = cls.from_directory(path=sdist_dir)
  
          if not info:
              return new_info
  
          return info.update(new_info)
  
      @staticmethod
      def has_setup_files(path: Path) -> bool:
          return any((path / f).exists() for f in SetupReader.FILES)
  
      @classmethod
      def from_setup_files(cls, path: Path) -> "PackageInfo":
          """
          Mechanism to parse package information from a `setup.[py|cfg]` file. This uses the implementation
          at `poetry.utils.setup_reader.SetupReader` in order to parse the file. This is not reliable for
          complex setup files and should only attempted as a fallback.
  
          :param path: Path to `setup.py` file
          """
          if not cls.has_setup_files(path):
              raise PackageInfoError(
                  path, "No setup files (setup.py, setup.cfg) was found."
              )
  
          try:
              result = SetupReader.read_from_directory(path)
          except Exception as e:
              raise PackageInfoError(path, e)
  
          python_requires = result["python_requires"]
          if python_requires is None:
              python_requires = "*"
  
          requires = ""
          for dep in result["install_requires"]:
              requires += dep + "\n"
  
          if result["extras_require"]:
              requires += "\n"
  
          for extra_name, deps in result["extras_require"].items():
              requires += f"[{extra_name}]\n"
  
              for dep in deps:
                  requires += dep + "\n"
  
              requires += "\n"
  
          requirements = parse_requires(requires)
  
          info = cls(
              name=result.get("name"),
              version=result.get("version"),
              summary=result.get("description", ""),
              requires_dist=requirements or None,
              requires_python=python_requires,
          )
  
          if not (info.name and info.version) and not info.requires_dist:
              # there is nothing useful here
              raise PackageInfoError(
                  path,
                  "No core metadata (name, version, requires-dist) could be retrieved.",
              )
  
          return info
  
      @staticmethod
      def _find_dist_info(path: Path) -> Iterator[Path]:
          """
          Discover all `*.*-info` directories in a given path.
  
          :param path: Path to search.
          """
          pattern = "**/*.*-info"
          # Sometimes pathlib will fail on recursive symbolic links, so we need to workaround it
          # and use the glob module instead. Note that this does not happen with pathlib2
          # so it's safe to use it for Python < 3.4.
          directories = glob.iglob(path.joinpath(pattern).as_posix(), recursive=True)
  
          for d in directories:
              yield Path(d)
  
      @classmethod
      def from_metadata(cls, path: Path) -> Optional["PackageInfo"]:
          """
          Helper method to parse package information from an unpacked metadata directory.
  
          :param path: The metadata directory to parse information from.
          """
          if path.suffix in {".dist-info", ".egg-info"}:
              directories = [path]
          else:
              directories = cls._find_dist_info(path=path)
  
          for directory in directories:
              try:
                  if directory.suffix == ".egg-info":
                      dist = pkginfo.UnpackedSDist(directory.as_posix())
                  elif directory.suffix == ".dist-info":
                      dist = pkginfo.Wheel(directory.as_posix())
                  else:
                      continue
                  break
              except ValueError:
                  continue
          else:
              try:
                  # handle PKG-INFO in unpacked sdist root
                  dist = pkginfo.UnpackedSDist(path.as_posix())
              except ValueError:
                  return None
  
          info = cls._from_distribution(dist=dist)
          if info:
              return info
          return None
  
      @classmethod
      def from_package(cls, package: Package) -> "PackageInfo":
          """
          Helper method to inspect a `Package` object, in order to generate package info.
  
          :param package: This must be a poetry package instance.
          """
          requires = {dependency.to_pep_508() for dependency in package.requires}
  
          for extra_requires in package.extras.values():
              for dependency in extra_requires:
                  requires.add(dependency.to_pep_508())
  
          return cls(
              name=package.name,
              version=str(package.version),
              summary=package.description,
              platform=package.platform,
              requires_dist=list(requires),
              requires_python=package.python_versions,
              files=package.files,
          )
  
      @staticmethod
      def _get_poetry_package(path: Path) -> Optional["ProjectPackage"]:
          # Note: we ignore any setup.py file at this step
          # TODO: add support for handling non-poetry PEP-517 builds
          if PyProjectTOML(path.joinpath("pyproject.toml")).is_poetry_project():
              return Factory().create_poetry(path).package
          return None
  
      @classmethod
      def _pep517_metadata(cls, path: Path) -> "PackageInfo":
          """
          Helper method to use PEP-517 library to build and read package metadata.
  
          :param path: Path to package source to build and read metadata for.
          """
          info = None
          try:
              info = cls.from_setup_files(path)
              if all([info.version, info.name, info.requires_dist]):
                  return info
          except PackageInfoError:
              pass
  
          with ephemeral_environment(
              with_pip=True, with_wheel=True, with_setuptools=True
          ) as venv:
              # TODO: cache PEP 517 build environment corresponding to each project venv
              dest_dir = venv.path.parent / "dist"
              dest_dir.mkdir()
  
              pep517_meta_build_script = PEP517_META_BUILD.format(
                  source=path.as_posix(), dest=dest_dir.as_posix()
              )
  
              try:
                  venv.run_pip(
                      "install",
                      "--disable-pip-version-check",
                      "--ignore-installed",
                      *PEP517_META_BUILD_DEPS,
                  )
                  venv.run(
                      "python",
                      "-",
                      input_=pep517_meta_build_script,
                  )
                  return cls.from_metadata(dest_dir)
              except EnvCommandError as e:
                  # something went wrong while attempting pep517 metadata build
                  # fallback to egg_info if setup.py available
                  cls._log(f"PEP517 build failed: {e}", level="debug")
                  setup_py = path / "setup.py"
                  if not setup_py.exists():
                      raise PackageInfoError(
                          path,
                          e,
                          "No fallback setup.py file was found to generate egg_info.",
                      )
  
                  cwd = Path.cwd()
                  os.chdir(path.as_posix())
                  try:
                      venv.run("python", "setup.py", "egg_info")
                      return cls.from_metadata(path)
                  except EnvCommandError as fbe:
                      raise PackageInfoError(
                          path, "Fallback egg_info generation failed.", fbe
                      )
                  finally:
                      os.chdir(cwd.as_posix())
  
          if info:
              cls._log(f"Falling back to parsed setup.py file for {path}", "debug")
              return info
  
          # if we reach here, everything has failed and all hope is lost
          raise PackageInfoError(path, "Exhausted all core metadata sources.")
  
      @classmethod
      def from_directory(cls, path: Path, disable_build: bool = False) -> "PackageInfo":
          """
          Generate package information from a package source directory. If `disable_build` is not `True` and
          introspection of all available metadata fails, the package is attempted to be build in an isolated
          environment so as to generate required metadata.
  
          :param path: Path to generate package information from.
          :param disable_build: If not `True` and setup reader fails, PEP 517 isolated build is attempted in
              order to gather metadata.
          """
          project_package = cls._get_poetry_package(path)
          if project_package:
              info = cls.from_package(project_package)
          else:
              info = cls.from_metadata(path)
  
              if not info or info.requires_dist is None:
                  try:
                      if disable_build:
                          info = cls.from_setup_files(path)
                      else:
                          info = cls._pep517_metadata(path)
                  except PackageInfoError:
                      if not info:
                          raise
  
                      # we discovered PkgInfo but no requirements were listed
  
          info._source_type = "directory"
          info._source_url = path.as_posix()
  
          return info
  
      @classmethod
      def from_sdist(cls, path: Path) -> "PackageInfo":
          """
          Gather package information from an sdist file, packed or unpacked.
  
          :param path: Path to an sdist file or unpacked directory.
          """
          if path.is_file():
              return cls._from_sdist_file(path=path)
  
          # if we get here then it is neither an sdist instance nor a file
          # so, we assume this is an directory
          return cls.from_directory(path=path)
  
      @classmethod
      def from_wheel(cls, path: Path) -> "PackageInfo":
          """
          Gather package information from a wheel.
  
          :param path: Path to wheel.
          """
          try:
              return cls._from_distribution(pkginfo.Wheel(str(path)))
          except ValueError:
              return PackageInfo()
  
      @classmethod
      def from_bdist(cls, path: Path) -> "PackageInfo":
          """
          Gather package information from a bdist (wheel etc.).
  
          :param path: Path to bdist.
          """
          if isinstance(path, (pkginfo.BDist, pkginfo.Wheel)):
              cls._from_distribution(dist=path)
  
          if path.suffix == ".whl":
              return cls.from_wheel(path=path)
  
          try:
              return cls._from_distribution(pkginfo.BDist(str(path)))
          except ValueError as e:
              raise PackageInfoError(path, e)
  
      @classmethod
      def from_path(cls, path: Path) -> "PackageInfo":
          """
          Gather package information from a given path (bdist, sdist, directory).
  
          :param path: Path to inspect.
          """
          try:
              return cls.from_bdist(path=path)
          except PackageInfoError:
              return cls.from_sdist(path=path)
  