# dirstate.py - working directory tracking for mercurial

#

# Copyright 2005-2007 Matt Mackall <mpm@selenic.com>

#

# 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 collections

import contextlib

import errno

import os

import stat

from .i18n import _

from .node import nullid

from . import (

    encoding,

    error,

    match as matchmod,

    parsers,

    pathutil,

    pycompat,

    scmutil,

    txnutil,

    util,

)

propertycache = util.propertycache

filecache = scmutil.filecache

_rangemask = 0x7fffffff

dirstatetuple = parsers.dirstatetuple

class repocache(filecache):

    """filecache for files in .hg/"""

    def join(self, obj, fname):

        return obj._opener.join(fname)

class rootcache(filecache):

    """filecache for files in the repository root"""

    def join(self, obj, fname):

        return obj._join(fname)

def _getfsnow(vfs):

    '''Get "now" timestamp on filesystem'''

    tmpfd, tmpname = vfs.mkstemp()

    try:

        return os.fstat(tmpfd).st_mtime

    finally:

        os.close(tmpfd)

        vfs.unlink(tmpname)

def nonnormalentries(dmap):

    '''Compute the nonnormal dirstate entries from the dmap'''

    try:

        return parsers.nonnormalotherparententries(dmap)

    except AttributeError:

        nonnorm = set()

        otherparent = set()

        for fname, e in dmap.iteritems():

            if e[0] != 'n' or e[3] == -1:

                nonnorm.add(fname)

            if e[0] == 'n' and e[2] == -2:

                otherparent.add(fname)

        return nonnorm, otherparent

class dirstate(object):

    def __init__(self, opener, ui, root, validate):

        '''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.

        '''

        self._opener = opener

        self._validate = validate

        self._root = root

        # ntpath.join(root, '') of Python 2.7.9 does not add sep if root is

        # UNC path pointing to root share (issue4557)

        self._rootdir = pathutil.normasprefix(root)

        # internal config: ui.forcecwd

        forcecwd = ui.config('ui', 'forcecwd')

        if forcecwd:

            self._cwd = forcecwd

        self._dirty = False

        self._dirtypl = False

        self._lastnormaltime = 0

        self._ui = ui

        self._filecache = {}

        self._parentwriters = 0

        self._filename = 'dirstate'

        self._pendingfilename = '%s.pending' % self._filename

        self._plchangecallbacks = {}

        self._origpl = None

        self._updatedfiles = set()

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

        self._pendingmode = None

    @contextlib.contextmanager

    def parentchange(self):

        '''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.

        '''

        self._parentwriters += 1

        yield

        # Typically we want the "undo" step of a context manager in a

        # finally block so it happens even when an exception

        # occurs. In this case, however, we only want to decrement

        # parentwriters if the code in the with statement exits

        # normally, so we don't have a try/finally here on purpose.

        self._parentwriters -= 1

    def beginparentchange(self):

        '''Marks the beginning of a set of changes that involve changing

        the dirstate parents. If there is an exception during this time,

        the dirstate will not be written when the wlock is released. This

        prevents writing an incoherent dirstate where the parent doesn't

        match the contents.

        '''

        self._parentwriters += 1

    def endparentchange(self):

        '''Marks the end of a set of changes that involve changing the

        dirstate parents. Once all parent changes have been marked done,

        the wlock will be free to write the dirstate on release.

        '''

        if self._parentwriters > 0:

            self._parentwriters -= 1

    def pendingparentchange(self):

        '''Returns true if the dirstate is in the middle of a set of changes

        that modify the dirstate parent.

        '''

        return self._parentwriters > 0

    @propertycache

    def _map(self):

        '''Return the dirstate contents as a map from filename to

        (state, mode, size, time).'''

        self._read()

        return self._map

    @propertycache

    def _copymap(self):

        self._read()

        return self._copymap

    @propertycache

    def _nonnormalset(self):

        nonnorm, otherparents = nonnormalentries(self._map)

        self._otherparentset = otherparents

        return nonnorm

    @propertycache

    def _otherparentset(self):

        nonnorm, otherparents = nonnormalentries(self._map)

        self._nonnormalset = nonnorm

        return otherparents

    @propertycache

    def _filefoldmap(self):

        try:

            makefilefoldmap = parsers.make_file_foldmap

        except AttributeError:

            pass

        else:

            return makefilefoldmap(self._map, util.normcasespec,

                                   util.normcasefallback)

        f = {}

        normcase = util.normcase

        for name, s in self._map.iteritems():

            if s[0] != 'r':

                f[normcase(name)] = name

        f['.'] = '.' # prevents useless util.fspath() invocation

        return f

    @propertycache

    def _dirfoldmap(self):

        f = {}

        normcase = util.normcase

        for name in self._dirs:

            f[normcase(name)] = name

        return f

    @repocache('branch')

    def _branch(self):

        try:

            return self._opener.read("branch").strip() or "default"

        except IOError as inst:

            if inst.errno != errno.ENOENT:

                raise

            return "default"

    @propertycache

    def _pl(self):

        try:

            fp = self._opendirstatefile()

            st = fp.read(40)

            fp.close()

            l = len(st)

            if l == 40:

                return st[:20], st[20:40]

            elif l > 0 and l < 40:

                raise error.Abort(_('working directory state appears damaged!'))

        except IOError as err:

            if err.errno != errno.ENOENT:

                raise

        return [nullid, nullid]

    @propertycache

    def _dirs(self):

        return util.dirs(self._map, 'r')

    def dirs(self):

        return self._dirs

    @rootcache('.hgignore')

    def _ignore(self):

        files = self._ignorefiles()

        if not files:

            return util.never

        pats = ['include:%s' % f for f in files]

        return matchmod.match(self._root, '', [], pats, warn=self._ui.warn)

    @propertycache

    def _slash(self):

        return self._ui.configbool('ui', 'slash') and pycompat.ossep != '/'

    @propertycache

    def _checklink(self):

        return util.checklink(self._root)

    @propertycache

    def _checkexec(self):

        return util.checkexec(self._root)

    @propertycache

    def _checkcase(self):

        return not util.fscasesensitive(self._join('.hg'))

    def _join(self, f):

        # much faster than os.path.join()

        # it's safe because f is always a relative path

        return self._rootdir + f

    def flagfunc(self, buildfallback):

        if self._checklink and self._checkexec:

            def f(x):

                try:

                    st = os.lstat(self._join(x))

                    if util.statislink(st):

                        return 'l'

                    if util.statisexec(st):

                        return 'x'

                except OSError:

                    pass

                return ''

            return f

        fallback = buildfallback()

        if self._checklink:

            def f(x):

                if os.path.islink(self._join(x)):

                    return 'l'

                if 'x' in fallback(x):

                    return 'x'

                return ''

            return f

        if self._checkexec:

            def f(x):

                if 'l' in fallback(x):

                    return 'l'

                if util.isexec(self._join(x)):

                    return 'x'

                return ''

            return f

        else:

            return fallback

    @propertycache

    def _cwd(self):

        return pycompat.getcwd()

    def getcwd(self):

        '''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.

        '''

        cwd = self._cwd

        if cwd == self._root:

            return ''

        # self._root ends with a path separator if self._root is '/' or 'C:\'

        rootsep = self._root

        if not util.endswithsep(rootsep):

            rootsep += pycompat.ossep

        if cwd.startswith(rootsep):

            return cwd[len(rootsep):]

        else:

            # we're outside the repo. return an absolute path.

            return cwd

    def pathto(self, f, cwd=None):

        if cwd is None:

            cwd = self.getcwd()

        path = util.pathto(self._root, cwd, f)

        if self._slash:

            return util.pconvert(path)

        return path

    def __getitem__(self, key):

        '''Return the current state of key (a filename) in the dirstate.

        States are:

          n  normal

          m  needs merging

          r  marked for removal

          a  marked for addition

          ?  not tracked

        '''

        return self._map.get(key, ("?",))[0]

    def __contains__(self, key):

        return key in self._map

    def __iter__(self):

        for x in sorted(self._map):

            yield x

    def iteritems(self):

        return self._map.iteritems()

    def parents(self):

        return [self._validate(p) for p in self._pl]

    def p1(self):

        return self._validate(self._pl[0])

    def p2(self):

        return self._validate(self._pl[1])

    def branch(self):

        return encoding.tolocal(self._branch)

    def setparents(self, p1, p2=nullid):

        """Set dirstate parents to p1 and p2.

        When moving from two parents to one, 'm' merged entries a

        adjusted to normal and previous copy records discarded and

        returned by the call.

        See localrepo.setparents()

        """

        if self._parentwriters == 0:

            raise ValueError("cannot set dirstate parent without "

                             "calling dirstate.beginparentchange")

        self._dirty = self._dirtypl = True

        oldp2 = self._pl[1]

        if self._origpl is None:

            self._origpl = self._pl

        self._pl = p1, p2

        copies = {}

        if oldp2 != nullid and p2 == nullid:

            candidatefiles = self._nonnormalset.union(self._otherparentset)

            for f in candidatefiles:

                s = self._map.get(f)

                if s is None:

                    continue

                # Discard 'm' markers when moving away from a merge state

                if s[0] == 'm':

                    if f in self._copymap:

                        copies[f] = self._copymap[f]

                    self.normallookup(f)

                # Also fix up otherparent markers