"""The HFS file entry implementation."""

import copy

from dfdatetime import hfs_time as dfdatetime_hfs_time
from dfdatetime import posix_time as dfdatetime_posix_time

from dfvfs.lib import definitions
from dfvfs.lib import errors
from dfvfs.path import hfs_path_spec
from dfvfs.resolver import resolver
from dfvfs.vfs import attribute
from dfvfs.vfs import extent
from dfvfs.vfs import file_entry
from dfvfs.vfs import hfs_attribute
from dfvfs.vfs import hfs_data_stream
from dfvfs.vfs import hfs_directory


class HFSFileEntry(file_entry.FileEntry):
    """File system file entry that uses pyfshfs."""

    TYPE_INDICATOR = definitions.TYPE_INDICATOR_HFS

    # Mappings of HFS file types to dfVFS file entry types.
    _ENTRY_TYPES = {
        0x1000: definitions.FILE_ENTRY_TYPE_PIPE,
        0x2000: definitions.FILE_ENTRY_TYPE_CHARACTER_DEVICE,
        0x4000: definitions.FILE_ENTRY_TYPE_DIRECTORY,
        0x6000: definitions.FILE_ENTRY_TYPE_BLOCK_DEVICE,
        0x8000: definitions.FILE_ENTRY_TYPE_FILE,
        0xA000: definitions.FILE_ENTRY_TYPE_LINK,
        0xC000: definitions.FILE_ENTRY_TYPE_SOCKET,
        0xE000: definitions.FILE_ENTRY_TYPE_WHITEOUT,
    }

    def __init__(
        self,
        resolver_context,
        file_system,
        path_spec,
        fshfs_file_entry=None,
        is_root=False,
        is_virtual=False,
    ):
        """Initializes a file entry.

        Args:
          resolver_context (Context): resolver context.
          file_system (FileSystem): file system.
          path_spec (PathSpec): path specification.
          fshfs_file_entry (Optional[pyfshfs.file_entry]): HFS file entry.
          is_root (Optional[bool]): True if the file entry is the root file entry
              of the corresponding file system.
          is_virtual (Optional[bool]): True if the file entry is a virtual file
              entry emulated by the corresponding file system.

        Raises:
          BackEndError: if the pyfshfs file entry is missing.
        """
        if not fshfs_file_entry:
            fshfs_file_entry = file_system.GetHFSFileEntryByPathSpec(path_spec)
        if not fshfs_file_entry:
            raise errors.BackEndError("Missing pyfshfs file entry.")

        if is_root:
            file_entry_name = ""
        else:
            file_entry_name = fshfs_file_entry.name

        super().__init__(
            resolver_context,
            file_system,
            path_spec,
            is_root=is_root,
            is_virtual=is_virtual,
        )
        self._fshfs_file_entry = fshfs_file_entry
        self._name = file_entry_name

        self.entry_type = self._ENTRY_TYPES.get(
            fshfs_file_entry.file_mode & 0xF000, None
        )

    def _GetAttributes(self):
        """Retrieves the attributes.

        Returns:
          list[Attribute]: attributes.
        """
        if self._attributes is None:
            self._attributes = []

            for fshfs_extended_attribute in self._fshfs_file_entry.extended_attributes:
                extended_attribute = hfs_attribute.HFSExtendedAttribute(
                    fshfs_extended_attribute
                )
                self._attributes.append(extended_attribute)

        return self._attributes

    def _GetDataStreams(self):
        """Retrieves the data streams.

        Returns:
          list[HFSDataStream]: data streams.
        """
        if self._data_streams is None:
            self._data_streams = []

            if self.entry_type == definitions.FILE_ENTRY_TYPE_FILE:
                data_stream = hfs_data_stream.HFSDataStream(self, None)
                self._data_streams.append(data_stream)

            fshfs_data_stream = self._fshfs_file_entry.get_resource_fork()
            if fshfs_data_stream:
                data_stream = hfs_data_stream.HFSDataStream(self, fshfs_data_stream)
                self._data_streams.append(data_stream)

        return self._data_streams

    def _GetDirectory(self):
        """Retrieves a directory.

        Returns:
          HFSDirectory: directory or None if not available.
        """
        if self.entry_type != definitions.FILE_ENTRY_TYPE_DIRECTORY:
            return None

        return hfs_directory.HFSDirectory(
            self._file_system, self.path_spec, self._fshfs_file_entry
        )

    def _GetLink(self):
        """Retrieves the link.

        Returns:
          str: path of the linked file.
        """
        if self._link is None:
            self._link = self._fshfs_file_entry.symbolic_link_target

        return self._link

    def _GetStatAttribute(self):
        """Retrieves a stat attribute.

        Returns:
          StatAttribute: a stat attribute or None if not available.
        """
        stat_attribute = attribute.StatAttribute()
        stat_attribute.device_number = self._fshfs_file_entry.device_number
        stat_attribute.group_identifier = self._fshfs_file_entry.group_identifier
        stat_attribute.inode_number = self._fshfs_file_entry.identifier
        stat_attribute.mode = self._fshfs_file_entry.file_mode
        stat_attribute.number_of_links = self._fshfs_file_entry.number_of_links
        stat_attribute.owner_identifier = self._fshfs_file_entry.owner_identifier
        stat_attribute.size = self._fshfs_file_entry.size
        stat_attribute.type = self.entry_type

        return stat_attribute

    def _GetSubFileEntries(self):
        """Retrieves a sub file entries generator.

        Yields:
          HFSFileEntry: a sub file entry.
        """
        if self._directory is None:
            self._directory = self._GetDirectory()

        if self._directory:
            for path_spec in self._directory.entries:
                yield HFSFileEntry(self._resolver_context, self._file_system, path_spec)

    @property
    def access_time(self):
        """dfdatetime.DateTimeValues: access time or None if not available."""
        timestamp = self._fshfs_file_entry.get_access_time_as_integer()
        if timestamp is None:
            return None

        return dfdatetime_hfs_time.HFSTime(timestamp=timestamp)

    @property
    def added_time(self):
        """dfdatetime.DateTimeValues: added time or None if not available."""
        timestamp = self._fshfs_file_entry.get_added_time_as_integer()
        if timestamp is None:
            return None

        return dfdatetime_posix_time.PosixTime(timestamp=timestamp)

    @property
    def backup_time(self):
        """dfdatetime.DateTimeValues: backup time or None if not available."""
        timestamp = self._fshfs_file_entry.get_backup_time_as_integer()
        return dfdatetime_hfs_time.HFSTime(timestamp=timestamp)

    @property
    def change_time(self):
        """dfdatetime.DateTimeValues: change time or None if not available."""
        timestamp = self._fshfs_file_entry.get_entry_modification_time_as_integer()
        if timestamp is None:
            return None

        return dfdatetime_hfs_time.HFSTime(timestamp=timestamp)

    @property
    def creation_time(self):
        """dfdatetime.DateTimeValues: creation time or None if not available."""
        timestamp = self._fshfs_file_entry.get_creation_time_as_integer()
        return dfdatetime_hfs_time.HFSTime(timestamp=timestamp)

    @property
    def name(self):
        """str: name of the file entry, which does not include the full path."""
        return self._name

    @property
    def modification_time(self):
        """dfdatetime.DateTimeValues: modification time or None if not available."""
        timestamp = self._fshfs_file_entry.get_modification_time_as_integer()
        return dfdatetime_hfs_time.HFSTime(timestamp=timestamp)

    @property
    def size(self):
        """int: size of the file entry in bytes or None if not available."""
        return self._fshfs_file_entry.size

    def GetExtents(self):
        """Retrieves the extents.

        Returns:
          list[Extent]: the extents.
        """
        if self.entry_type != definitions.FILE_ENTRY_TYPE_FILE:
            return []

        extents = []
        for extent_index in range(self._fshfs_file_entry.number_of_extents):
            extent_offset, extent_size, extent_flags = (
                self._fshfs_file_entry.get_extent(extent_index)
            )

            if extent_flags & 0x1:
                extent_type = definitions.EXTENT_TYPE_SPARSE
            else:
                extent_type = definitions.EXTENT_TYPE_DATA

            data_stream_extent = extent.Extent(
                extent_type=extent_type, offset=extent_offset, size=extent_size
            )
            extents.append(data_stream_extent)

        return extents

    def GetFileObject(self, data_stream_name=""):
        """Retrieves a file-like object of a specific data stream.

        Args:
          data_stream_name (Optional[str]): name of the data stream, where an empty
              string represents the default data stream.

        Returns:
          FileIO: a file-like object or None if not available.
        """
        if self.entry_type != definitions.FILE_ENTRY_TYPE_FILE or (
            data_stream_name and data_stream_name != "rsrc"
        ):
            return None

        # Make sure to make the changes on a copy of the path specification, so we
        # do not alter self.path_spec.
        path_spec = copy.deepcopy(self.path_spec)
        if data_stream_name:
            setattr(path_spec, "data_stream", data_stream_name)

        return resolver.Resolver.OpenFileObject(
            path_spec, resolver_context=self._resolver_context
        )

    def GetHFSFileEntry(self):
        """Retrieves the HFS file entry.

        Returns:
          pyfshfs.file_entry: HFS file entry.
        """
        return self._fshfs_file_entry

    def GetLinkedFileEntry(self):
        """Retrieves the linked file entry, e.g. for a symbolic link.

        Returns:
          HFSFileEntry: linked file entry or None if not available.
        """
        link = self._GetLink()
        if not link:
            return None

        parent_path_spec = getattr(self.path_spec, "parent", None)
        path_spec = hfs_path_spec.HFSPathSpec(location=link, parent=parent_path_spec)

        is_root = bool(link == self._file_system.LOCATION_ROOT)

        return HFSFileEntry(
            self._resolver_context, self._file_system, path_spec, is_root=is_root
        )

    def GetParentFileEntry(self):
        """Retrieves the parent file entry.

        Returns:
          HFSFileEntry: parent file entry or None if not available.
        """
        parent_location = None

        location = getattr(self.path_spec, "location", None)
        if location is not None:
            parent_location = self._file_system.DirnamePath(location)
            if parent_location == "":
                parent_location = self._file_system.PATH_SEPARATOR

        parent_path_spec = getattr(self.path_spec, "parent", None)
        path_spec = hfs_path_spec.HFSPathSpec(
            location=parent_location, parent=parent_path_spec
        )

        is_root = bool(parent_location == self._file_system.LOCATION_ROOT)

        return HFSFileEntry(
            self._resolver_context, self._file_system, path_spec, is_root=is_root
        )
