# dirstatemap.py

#

# This software may be used and distributed according to the terms of the

# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

import errno

from .i18n import _

from . import (

    error,

    pathutil,

    policy,

    pycompat,

    txnutil,

    util,

)

from .dirstateutils import (

    docket as docketmod,

)

parsers = policy.importmod('parsers')

rustmod = policy.importrust('dirstate')

propertycache = util.propertycache

if rustmod is None:

    DirstateItem = parsers.DirstateItem

else:

    DirstateItem = rustmod.DirstateItem

rangemask = 0x7FFFFFFF

class _dirstatemapcommon(object):

    """

    Methods that are identical for both implementations of the dirstatemap

    class, with and without Rust extensions enabled.

    """

    # please pytype

    _map = None

    copymap = None

    def __init__(self, ui, opener, root, nodeconstants, use_dirstate_v2):

        self._use_dirstate_v2 = use_dirstate_v2

        self._nodeconstants = nodeconstants

        self._ui = ui

        self._opener = opener

        self._root = root

        self._filename = b'dirstate'

        self._nodelen = 20  # Also update Rust code when changing this!

        self._parents = None

        self._dirtyparents = False

        # for consistent view between _pl() and _read() invocations

        self._pendingmode = None

    def preload(self):

        """Loads the underlying data, if it's not already loaded"""

        self._map

    def get(self, key, default=None):

        return self._map.get(key, default)

    def __len__(self):

        return len(self._map)

    def __iter__(self):

        return iter(self._map)

    def __contains__(self, key):

        return key in self._map

    def __getitem__(self, item):

        return self._map[item]

    ### sub-class utility method

    #

    # Use to allow for generic implementation of some method while still coping

    # with minor difference between implementation.

    def _dirs_incr(self, filename, old_entry=None):

        """incremente the dirstate counter if applicable

        This might be a no-op for some subclass who deal with directory

        tracking in a different way.

        """

    def _dirs_decr(self, filename, old_entry=None, remove_variant=False):

        """decremente the dirstate counter if applicable

        This might be a no-op for some subclass who deal with directory

        tracking in a different way.

        """

    def _refresh_entry(self, f, entry):

        """record updated state of an entry"""

    def _insert_entry(self, f, entry):

        """add a new dirstate entry (or replace an unrelated one)

        The fact it is actually new is the responsability of the caller

        """

    def _drop_entry(self, f):

        """remove any entry for file f

        This should also drop associated copy information

        The fact we actually need to drop it is the responsability of the caller"""

    ### method to manipulate the entries

    def set_possibly_dirty(self, filename):

        """record that the current state of the file on disk is unknown"""

        entry = self[filename]

        entry.set_possibly_dirty()

        self._refresh_entry(filename, entry)

    def set_clean(self, filename, mode, size, mtime):

        """mark a file as back to a clean state"""

        entry = self[filename]

        mtime = mtime & rangemask

        size = size & rangemask

        entry.set_clean(mode, size, mtime)

        self._refresh_entry(filename, entry)

        self.copymap.pop(filename, None)

    def set_tracked(self, filename):

        new = False

        entry = self.get(filename)

        if entry is None:

            self._dirs_incr(filename)

            entry = DirstateItem(

                wc_tracked=True,

            )

            self._insert_entry(filename, entry)

            new = True

        elif not entry.tracked:

            self._dirs_incr(filename, entry)

            entry.set_tracked()

            self._refresh_entry(filename, entry)

            new = True

        else:

            # XXX This is probably overkill for more case, but we need this to

            # fully replace the `normallookup` call with `set_tracked` one.

            # Consider smoothing this in the future.

            entry.set_possibly_dirty()

            self._refresh_entry(filename, entry)

        return new

    def set_untracked(self, f):

        """Mark a file as no longer tracked in the dirstate map"""

        entry = self.get(f)

        if entry is None:

            return False

        else:

            self._dirs_decr(f, old_entry=entry, remove_variant=not entry.added)

            if not entry.merged:

                self.copymap.pop(f, None)

            entry.set_untracked()

            self._refresh_entry(f, entry)

            return True

    def reset_state(

        self,

        filename,

        wc_tracked=False,

        p1_tracked=False,

        p2_tracked=False,

        merged=False,

        clean_p1=False,

        clean_p2=False,

        possibly_dirty=False,

        parentfiledata=None,

    ):

        """Set a entry to a given state, diregarding all previous state

        This is to be used by the part of the dirstate API dedicated to

        adjusting the dirstate after a update/merge.

        note: calling this might result to no entry existing at all if the

        dirstate map does not see any point at having one for this file

        anymore.

        """

        if merged and (clean_p1 or clean_p2):

            msg = b'`merged` argument incompatible with `clean_p1`/`clean_p2`'

            raise error.ProgrammingError(msg)

        # copy information are now outdated

        # (maybe new information should be in directly passed to this function)

        self.copymap.pop(filename, None)

        if not (p1_tracked or p2_tracked or wc_tracked):

            old_entry = self._map.get(filename)

            self._drop_entry(filename)

            self._dirs_decr(filename, old_entry=old_entry)

            return

        old_entry = self._map.get(filename)

        self._dirs_incr(filename, old_entry)

        entry = DirstateItem(

            wc_tracked=wc_tracked,

            p1_tracked=p1_tracked,

            parentfiledata=parentfiledata,

        )

        self._insert_entry(filename, entry)

class dirstatemap(_dirstatemapcommon):

    """Map encapsulating the dirstate's contents.

    The dirstate contains the following state:

    - `identity` is the identity of the dirstate file, which can be used to

      detect when changes have occurred to the dirstate file.

    - `parents` is a pair containing the parents of the working copy. The

      parents are updated by calling `setparents`.

    - the state map maps filenames to tuples of (state, mode, size, mtime),

      where state is a single character representing 'normal', 'added',

      'removed', or 'merged'. It is read by treating the dirstate as a

      dict.  File state is updated by calling various methods (see each

      documentation for details):

      - `reset_state`,

      - `set_tracked`

      - `set_untracked`

      - `set_clean`

      - `set_possibly_dirty`

    - `copymap` maps destination filenames to their source filename.

    The dirstate also provides the following views onto the state:

    - `filefoldmap` is a dict mapping normalized filenames to the denormalized

      form that they appear as in the dirstate.

    - `dirfoldmap` is a dict mapping normalized directory names to the

      denormalized form that they appear as in the dirstate.

    """

    def __init__(self, ui, opener, root, nodeconstants, use_dirstate_v2):

        super(dirstatemap, self).__init__(

            ui, opener, root, nodeconstants, use_dirstate_v2

        )

        if self._use_dirstate_v2:

            msg = "Dirstate V2 not supportedi"

            msg += "(should have detected unsupported requirement)"

            raise error.ProgrammingError(msg)

    ### Core data storage and access

    @propertycache

    def _map(self):

        self._map = {}

        self.read()

        return self._map

    @propertycache

    def copymap(self):

        self.copymap = {}

        self._map

        return self.copymap

    def clear(self):

        self._map.clear()

        self.copymap.clear()

        self.setparents(self._nodeconstants.nullid, self._nodeconstants.nullid)

        util.clearcachedproperty(self, b"_dirs")

        util.clearcachedproperty(self, b"_alldirs")

        util.clearcachedproperty(self, b"filefoldmap")

        util.clearcachedproperty(self, b"dirfoldmap")

    def items(self):

        return pycompat.iteritems(self._map)

    # forward for python2,3 compat

    iteritems = items

    def debug_iter(self, all):

        """

        Return an iterator of (filename, state, mode, size, mtime) tuples

        `all` is unused when Rust is not enabled

        """

        for (filename, item) in self.items():

            yield (filename, item.state, item.mode, item.size, item.mtime)

    def keys(self):

        return self._map.keys()

    ### reading/setting parents

    def parents(self):

        if not self._parents:

            try:

                fp = self._opendirstatefile()

                st = fp.read(2 * self._nodelen)

                fp.close()

            except IOError as err:

                if err.errno != errno.ENOENT:

                    raise

                # File doesn't exist, so the current state is empty

                st = b''

            l = len(st)

            if l == self._nodelen * 2:

                self._parents = (

                    st[: self._nodelen],

                    st[self._nodelen : 2 * self._nodelen],

                )

            elif l == 0:

                self._parents = (

                    self._nodeconstants.nullid,

                    self._nodeconstants.nullid,

                )

            else:

                raise error.Abort(

                    _(b'working directory state appears damaged!')

                )

        return self._parents

    def setparents(self, p1, p2, fold_p2=False):

        self._parents = (p1, p2)

        self._dirtyparents = True

        copies = {}

        if fold_p2:

            for f, s in pycompat.iteritems(self._map):

                # Discard "merged" markers when moving away from a merge state

                if s.merged or s.from_p2:

                    source = self.copymap.pop(f, None)

                    if source:

                        copies[f] = source

                    s.drop_merge_data()

        return copies

    ### disk interaction

    def read(self):

        # ignore HG_PENDING because identity is used only for writing

        self.identity = util.filestat.frompath(

            self._opener.join(self._filename)

        )

        try:

            fp = self._opendirstatefile()

            try:

                st = fp.read()

            finally:

                fp.close()

        except IOError as err:

            if err.errno != errno.ENOENT:

                raise

            return

        if not st:

            return

        if util.safehasattr(parsers, b'dict_new_presized'):

            # Make an estimate of the number of files in the dirstate based on

            # its size. This trades wasting some memory for avoiding costly

            # resizes. Each entry have a prefix of 17 bytes followed by one or

            # two path names. Studies on various large-scale real-world repositories

            # found 54 bytes a reasonable upper limit for the average path names.

            # Copy entries are ignored for the sake of this estimate.

            self._map = parsers.dict_new_presized(len(st) // 71)

        # Python's garbage collector triggers a GC each time a certain number

        # of container objects (the number being defined by

        # gc.get_threshold()) are allocated. parse_dirstate creates a tuple

        # for each file in the dirstate. The C version then immediately marks

        # them as not to be tracked by the collector. However, this has no

        # effect on when GCs are triggered, only on what objects the GC looks

        # into. This means that O(number of files) GCs are unavoidable.

        # Depending on when in the process's lifetime the dirstate is parsed,

        # this can get very expensive. As a workaround, disable GC while

        # parsing the dirstate.

        #

        # (we cannot decorate the function directly since it is in a C module)

        parse_dirstate = util.nogc(parsers.parse_dirstate)

        p = parse_dirstate(self._map, self.copymap, st)

        if not self._dirtyparents:

            self.setparents(*p)

        # Avoid excess attribute lookups by fast pathing certain checks

        self.__contains__ = self._map.__contains__

        self.__getitem__ = self._map.__getitem__

        self.get = self._map.get