text: """Cache Management
  """
  
  import hashlib
  import json
  import logging
  import os
  from typing import Any, Dict, List, Optional, Set
  
  from pipenv.patched.notpip._vendor.packaging.tags import Tag, interpreter_name, interpreter_version
  from pipenv.patched.notpip._vendor.packaging.utils import canonicalize_name
  
  from pipenv.patched.notpip._internal.exceptions import InvalidWheelFilename
  from pipenv.patched.notpip._internal.models.format_control import FormatControl
  from pipenv.patched.notpip._internal.models.link import Link
  from pipenv.patched.notpip._internal.models.wheel import Wheel
  from pipenv.patched.notpip._internal.utils.temp_dir import TempDirectory, tempdir_kinds
  from pipenv.patched.notpip._internal.utils.urls import path_to_url
  
  logger = logging.getLogger(__name__)
  
  
  def _hash_dict(d: Dict[str, str]) -> str:
      """Return a stable sha224 of a dictionary."""
      s = json.dumps(d, sort_keys=True, separators=(",", ":"), ensure_ascii=True)
      return hashlib.sha224(s.encode("ascii")).hexdigest()
  
  
  class Cache:
      """An abstract class - provides cache directories for data from links
  
  
      :param cache_dir: The root of the cache.
      :param format_control: An object of FormatControl class to limit
          binaries being read from the cache.
      :param allowed_formats: which formats of files the cache should store.
          ('binary' and 'source' are the only allowed values)
      """
  
      def __init__(
          self, cache_dir: str, format_control: FormatControl, allowed_formats: Set[str]
      ) -> None:
          super().__init__()
          assert not cache_dir or os.path.isabs(cache_dir)
          self.cache_dir = cache_dir or None
          self.format_control = format_control
          self.allowed_formats = allowed_formats
  
          _valid_formats = {"source", "binary"}
          assert self.allowed_formats.union(_valid_formats) == _valid_formats
  
      def _get_cache_path_parts(self, link: Link) -> List[str]:
          """Get parts of part that must be os.path.joined with cache_dir"""
  
          # We want to generate an url to use as our cache key, we don't want to
          # just re-use the URL because it might have other items in the fragment
          # and we don't care about those.
          key_parts = {"url": link.url_without_fragment}
          if link.hash_name is not None and link.hash is not None:
              key_parts[link.hash_name] = link.hash
          if link.subdirectory_fragment:
              key_parts["subdirectory"] = link.subdirectory_fragment
  
          # Include interpreter name, major and minor version in cache key
          # to cope with ill-behaved sdists that build a different wheel
          # depending on the python version their setup.py is being run on,
          # and don't encode the difference in compatibility tags.
          # https://github.com/pypa/pip/issues/7296
          key_parts["interpreter_name"] = interpreter_name()
          key_parts["interpreter_version"] = interpreter_version()
  
          # Encode our key url with sha224, we'll use this because it has similar
          # security properties to sha256, but with a shorter total output (and
          # thus less secure). However the differences don't make a lot of
          # difference for our use case here.
          hashed = _hash_dict(key_parts)
  
          # We want to nest the directories some to prevent having a ton of top
          # level directories where we might run out of sub directories on some
          # FS.
          parts = [hashed[:2], hashed[2:4], hashed[4:6], hashed[6:]]
  
          return parts
  
      def _get_candidates(self, link: Link, canonical_package_name: str) -> List[Any]:
          can_not_cache = not self.cache_dir or not canonical_package_name or not link
          if can_not_cache:
              return []
  
          formats = self.format_control.get_allowed_formats(canonical_package_name)
          if not self.allowed_formats.intersection(formats):
              return []
  
          candidates = []
          path = self.get_path_for_link(link)
          if os.path.isdir(path):
              for candidate in os.listdir(path):
                  candidates.append((candidate, path))
          return candidates
  
      def get_path_for_link(self, link: Link) -> str:
          """Return a directory to store cached items in for link."""
          raise NotImplementedError()
  
      def get(
          self,
          link: Link,
          package_name: Optional[str],
          supported_tags: List[Tag],
      ) -> Link:
          """Returns a link to a cached item if it exists, otherwise returns the
          passed link.
          """
          raise NotImplementedError()
  
  
  class SimpleWheelCache(Cache):
      """A cache of wheels for future installs."""
  
      def __init__(self, cache_dir: str, format_control: FormatControl) -> None:
          super().__init__(cache_dir, format_control, {"binary"})
  
      def get_path_for_link(self, link: Link) -> str:
          """Return a directory to store cached wheels for link
  
          Because there are M wheels for any one sdist, we provide a directory
          to cache them in, and then consult that directory when looking up
          cache hits.
  
          We only insert things into the cache if they have plausible version
          numbers, so that we don't contaminate the cache with things that were
          not unique. E.g. ./package might have dozens of installs done for it
          and build a version of 0.0...and if we built and cached a wheel, we'd
          end up using the same wheel even if the source has been edited.
  
          :param link: The link of the sdist for which this will cache wheels.
          """
          parts = self._get_cache_path_parts(link)
          assert self.cache_dir
          # Store wheels within the root cache_dir
          return os.path.join(self.cache_dir, "wheels", *parts)
  
      def get(
          self,
          link: Link,
          package_name: Optional[str],
          supported_tags: List[Tag],
      ) -> Link:
          candidates = []
  
          if not package_name:
              return link
  
          canonical_package_name = canonicalize_name(package_name)
          for wheel_name, wheel_dir in self._get_candidates(link, canonical_package_name):
              try:
                  wheel = Wheel(wheel_name)
              except InvalidWheelFilename:
                  continue
              if canonicalize_name(wheel.name) != canonical_package_name:
                  logger.debug(
                      "Ignoring cached wheel %s for %s as it "
                      "does not match the expected distribution name %s.",
                      wheel_name,
                      link,
                      package_name,
                  )
                  continue
              if not wheel.supported(supported_tags):
                  # Built for a different python/arch/etc
                  continue
              candidates.append(
                  (
                      wheel.support_index_min(supported_tags),
                      wheel_name,
                      wheel_dir,
                  )
              )
  
          if not candidates:
              return link
  
          _, wheel_name, wheel_dir = min(candidates)
          return Link(path_to_url(os.path.join(wheel_dir, wheel_name)))
  
  
  class EphemWheelCache(SimpleWheelCache):
      """A SimpleWheelCache that creates it's own temporary cache directory"""
  
      def __init__(self, format_control: FormatControl) -> None:
          self._temp_dir = TempDirectory(
              kind=tempdir_kinds.EPHEM_WHEEL_CACHE,
              globally_managed=True,
          )
  
          super().__init__(self._temp_dir.path, format_control)
  
  
  class CacheEntry:
      def __init__(
          self,
          link: Link,
          persistent: bool,
      ):
          self.link = link
          self.persistent = persistent
  
  
  class WheelCache(Cache):
      """Wraps EphemWheelCache and SimpleWheelCache into a single Cache
  
      This Cache allows for gracefully degradation, using the ephem wheel cache
      when a certain link is not found in the simple wheel cache first.
      """
  
      def __init__(self, cache_dir: str, format_control: FormatControl) -> None:
          super().__init__(cache_dir, format_control, {"binary"})
          self._wheel_cache = SimpleWheelCache(cache_dir, format_control)
          self._ephem_cache = EphemWheelCache(format_control)
  
      def get_path_for_link(self, link: Link) -> str:
          return self._wheel_cache.get_path_for_link(link)
  
      def get_ephem_path_for_link(self, link: Link) -> str:
          return self._ephem_cache.get_path_for_link(link)
  
      def get(
          self,
          link: Link,
          package_name: Optional[str],
          supported_tags: List[Tag],
      ) -> Link:
          cache_entry = self.get_cache_entry(link, package_name, supported_tags)
          if cache_entry is None:
              return link
          return cache_entry.link
  
      def get_cache_entry(
          self,
          link: Link,
          package_name: Optional[str],
          supported_tags: List[Tag],
      ) -> Optional[CacheEntry]:
          """Returns a CacheEntry with a link to a cached item if it exists or
          None. The cache entry indicates if the item was found in the persistent
          or ephemeral cache.
          """
          retval = self._wheel_cache.get(
              link=link,
              package_name=package_name,
              supported_tags=supported_tags,
          )
          if retval is not link:
              return CacheEntry(retval, persistent=True)
  
          retval = self._ephem_cache.get(
              link=link,
              package_name=package_name,
              supported_tags=supported_tags,
          )
          if retval is not link:
              return CacheEntry(retval, persistent=False)
  
          return None
  