from __future__ import annotations

import abc

import contextlib

import os

import typing

from typing import (

    Any,

    Callable,

    Dict,

    Iterable,

    Iterator,

    List,

    Optional,

    Protocol,

    Tuple,

)

if typing.TYPE_CHECKING:

    # Almost all mercurial modules are only imported in the type checking phase

    # to avoid circular imports

    from . import (

        matcher,

        status as istatus,

    )

    # TODO: finish adding type hints

    AddParentChangeCallbackT = Callable[

        ["idirstate", Tuple[Any, Any], Tuple[Any, Any]], Any

    ]

    """The callback type for dirstate.addparentchangecallback()."""

    # TODO: add a Protocol for dirstatemap.DirStateItem? (It is

    #  conditionalized with python or rust implementations.  Also,

    #  git.dirstate needs to yield non-None from ``items()``.)

    DirstateItemT = Any  # dirstatemap.DirstateItem

    IgnoreFileAndLineT = Tuple[Optional[bytes], int, bytes]

    """The return type of dirstate._ignorefileandline(), which holds

    ``(file, lineno, originalline)``.

    """

    FlagFuncFallbackT = Callable[[], "FlagFuncReturnT"]

    """The type for the dirstate.flagfunc() fallback function."""

    FlagFuncReturnT = Callable[[bytes], bytes]

    """The return type of dirstate.flagfunc()."""

    # TODO: verify and complete this- it came from a pytype *.pyi file

    StatusReturnT = Tuple[Any, istatus.Status, Any]

    """The return type of dirstate.status()."""

    """The type for a transaction used with dirstate.

    This is meant to help callers avoid having to remember to delay the import

    of the transaction module.

    """

    # TODO: The value can also be mercurial.osutil.stat

    WalkReturnT = Dict[bytes, Optional[os.stat_result]]

    """The return type of dirstate.walk().

    The matched files are keyed in the dictionary, mapped to a stat-like object

    if the file exists.

    """

class idirstate(Protocol):

    # TODO: convert these constructor args to fields?

    # def __init__(

    #     self,

    #     opener,

    #     ui,

    #     root,

    #     validate,

    #     sparsematchfn,

    #     nodeconstants,

    #     use_dirstate_v2,

    #     use_tracked_hint=False,

    # ):

    #     """Create a new dirstate object.

    #

    #     opener is an open()-like callable that can be used to open the

    #     dirstate file; root is the root of the directory tracked by

    #     the dirstate.

    #     """

    # TODO: all these private methods and attributes should be made

    # public or removed from the interface.

    # TODO: decorate with `@rootcache(b'.hgignore')` like dirstate class?

    @property

    def _ignore(self) -> matcher.IMatcher:

        """Matcher for ignored files."""

    @property

    @abc.abstractmethod

    def is_changing_any(self) -> bool:

        """True if any changes in progress."""

    @property

    @abc.abstractmethod

    def is_changing_parents(self) -> bool:

        """True if parents changes in progress."""

    @property

    @abc.abstractmethod

    def is_changing_files(self) -> bool:

        """True if file tracking changes in progress."""

    @abc.abstractmethod

    def _ignorefileandline(self, f: bytes) -> IgnoreFileAndLineT:

        """Given a file `f`, return the ignore file and line that ignores it."""

    # TODO: decorate with `@util.propertycache` like dirstate class?

    #  (can't because circular import)

    @property

    @abc.abstractmethod

    def _checklink(self) -> bool:

        """Callable for checking symlinks."""  # TODO: this comment looks stale

    # TODO: decorate with `@util.propertycache` like dirstate class?

    #  (can't because circular import)

    @property

    @abc.abstractmethod

    def _checkexec(self) -> bool:

        """Callable for checking exec bits."""  # TODO: this comment looks stale

    @contextlib.contextmanager

    @abc.abstractmethod

    def changing_parents(self, repo) -> Iterator:  # TODO: typehint this

        """Context manager for handling dirstate parents.

        If an exception occurs in the scope of the context manager,

        the incoherent dirstate won't be written when wlock is

        released.

        """

    @contextlib.contextmanager

    @abc.abstractmethod

    def changing_files(self, repo) -> Iterator:  # TODO: typehint this

        """Context manager for handling dirstate files.

        If an exception occurs in the scope of the context manager,

        the incoherent dirstate won't be written when wlock is

        released.

        """

    @abc.abstractmethod

    def hasdir(self, d: bytes) -> bool:

        pass

    @abc.abstractmethod

    def flagfunc(self, buildfallback: FlagFuncFallbackT) -> FlagFuncReturnT:

        """build a callable that returns flags associated with a filename

        The information is extracted from three possible layers:

        1. the file system if it supports the information

        2. the "fallback" information stored in the dirstate if any

        3. a more expensive mechanism inferring the flags from the parents.

        """

    @abc.abstractmethod

    def getcwd(self) -> bytes:

        """Return the path from which a canonical path is calculated.

        This path should be used to resolve file patterns or to convert

        canonical paths back to file paths for display. It shouldn't be

        used to get real file paths. Use vfs functions instead.

        """

    @abc.abstractmethod

    def pathto(self, f: bytes, cwd: Optional[bytes] = None) -> bytes:

        pass

    @abc.abstractmethod

    def get_entry(self, path: bytes) -> DirstateItemT:

        """return a DirstateItem for the associated path"""

    @abc.abstractmethod

    def __contains__(self, key: Any) -> bool:

        """Check if bytestring `key` is known to the dirstate."""

    @abc.abstractmethod

    def __iter__(self) -> Iterator[bytes]:

        """Iterate the dirstate's contained filenames as bytestrings."""

    @abc.abstractmethod

    def items(self) -> Iterator[Tuple[bytes, DirstateItemT]]:

        """Iterate the dirstate's entries as (filename, DirstateItem.

        As usual, filename is a bytestring.

        """

    iteritems = items

    @abc.abstractmethod

    def parents(self) -> List[bytes]:

        pass

    @abc.abstractmethod

    def p1(self) -> bytes:

        pass

    @abc.abstractmethod

    def p2(self) -> bytes:

        pass

    @abc.abstractmethod

    def branch(self) -> bytes:

        pass

    # TODO: typehint the return.  It's a copies Map of some sort.

    @abc.abstractmethod

    def setparents(self, p1: bytes, p2: Optional[bytes] = None):

        """Set dirstate parents to p1 and p2.

        When moving from two parents to one, "merged" entries a

        adjusted to normal and previous copy records discarded and

        returned by the call.

        See localrepo.setparents()

        """

    @abc.abstractmethod

    def setbranch(

        self, branch: bytes, transaction: Optional[TransactionT]

    ) -> None:

        pass

    @abc.abstractmethod

    def invalidate(self) -> None:

        """Causes the next access to reread the dirstate.

        This is different from localrepo.invalidatedirstate() because it always

        rereads the dirstate. Use localrepo.invalidatedirstate() if you want to

        check whether the dirstate has changed before rereading it."""

    @abc.abstractmethod

    def copy(self, source: Optional[bytes], dest: bytes) -> None:

        """Mark dest as a copy of source. Unmark dest if source is None."""

    @abc.abstractmethod

    def copied(self, file: bytes) -> Optional[bytes]:

        pass

    @abc.abstractmethod

    def copies(self) -> Dict[bytes, bytes]:

        pass

    @abc.abstractmethod

    def normalize(

        self, path: bytes, isknown: bool = False, ignoremissing: bool = False

    ) -> bytes:

        """

        normalize the case of a pathname when on a casefolding filesystem

        isknown specifies whether the filename came from walking the

        disk, to avoid extra filesystem access.

        If ignoremissing is True, missing path are returned

        unchanged. Otherwise, we try harder to normalize possibly

        existing path components.

        The normalized case is determined based on the following precedence:

        - version of name already stored in the dirstate

        - version of name stored on disk

        - version provided via command arguments

        """

    @abc.abstractmethod

    def clear(self) -> None:

        pass

    @abc.abstractmethod

    def rebuild(

        self,

        parent: bytes,

        allfiles: Iterable[bytes],  # TODO: more than iterable? (uses len())

        changedfiles: Optional[Iterable[bytes]] = None,

    ) -> None:

        pass

    @abc.abstractmethod

    def write(self, tr: Optional[TransactionT]) -> None:

        pass

    @abc.abstractmethod

    def addparentchangecallback(

        self, category: bytes, callback: AddParentChangeCallbackT

    ) -> None:

        """add a callback to be called when the wd parents are changed

        Callback will be called with the following arguments:

            dirstate, (oldp1, oldp2), (newp1, newp2)

        Category is a unique identifier to allow overwriting an old callback

        with a newer callback.

        """

    @abc.abstractmethod

    def walk(

        self,

        match: matcher.IMatcher,

        subrepos: Any,  # TODO: figure out what this is

        unknown: bool,

        ignored: bool,

        full: bool = True,

    ) -> WalkReturnT:

        """

        Walk recursively through the directory tree, finding all files

        matched by match.

        If full is False, maybe skip some known-clean files.

        Return a dict mapping filename to stat-like object (either

        mercurial.osutil.stat instance or return value of os.stat()).

        """

    @abc.abstractmethod

    def status(

        self,

        match: matcher.IMatcher,

        subrepos: bool,

        ignored: bool,

        clean: bool,

        unknown: bool,

    ) -> StatusReturnT:

        """Determine the status of the working copy relative to the

        dirstate and return a pair of (unsure, status), where status is of type

        scmutil.status and:

          unsure:

            files that might have been modified since the dirstate was

            written, but need to be read to be sure (size is the same

            but mtime differs)

          status.modified:

            files that have definitely been modified since the dirstate

            was written (different size or mode)

          status.clean:

            files that have definitely not been modified since the

            dirstate was written

        """

    # TODO: could return a list, except git.dirstate is a generator

    @abc.abstractmethod

    def matches(self, match: matcher.IMatcher) -> Iterable[bytes]:

        """

        return files in the dirstate (in whatever state) filtered by match

        """

    # TODO: finish adding typehints here, and to subclasses

    @abc.abstractmethod

    def verify(

        self, m1, m2, p1: bytes, narrow_matcher: Optional[Any] = None

    ) -> Iterator[bytes]:

        """

        check the dirstate contents against the parent manifest and yield errors

        """