# Mercurial bookmark support code

#

# Copyright 2008 David Soria Parra <dsp@php.net>

#

# 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

import struct

from .i18n import _

from .node import (

    bin,

    hex,

    short,

    wdirid,

)

from . import (

    encoding,

    error,

    obsutil,

    pycompat,

    scmutil,

    txnutil,

    util,

)

# label constants

# until 3.5, bookmarks.current was the advertised name, not

# bookmarks.active, so we must use both to avoid breaking old

# custom styles

activebookmarklabel = 'bookmarks.active bookmarks.current'

BOOKMARKS_IN_STORE_REQUIREMENT = 'bookmarksinstore'

def bookmarksinstore(repo):

    return BOOKMARKS_IN_STORE_REQUIREMENT in repo.requirements

def bookmarksvfs(repo):

    return repo.svfs if bookmarksinstore(repo) else repo.vfs

def _getbkfile(repo):

    """Hook so that extensions that mess with the store can hook bm storage.

    For core, this just handles wether we should see pending

    bookmarks or the committed ones. Other extensions (like share)

    may need to tweak this behavior further.

    """

    fp, pending = txnutil.trypending(repo.root, bookmarksvfs(repo), 'bookmarks')

    return fp

class bmstore(object):

    r"""Storage for bookmarks.

    This object should do all bookmark-related reads and writes, so

    that it's fairly simple to replace the storage underlying

    bookmarks without having to clone the logic surrounding

    bookmarks. This type also should manage the active bookmark, if

    any.

    This particular bmstore implementation stores bookmarks as

    {hash}\s{name}\n (the same format as localtags) in

    .hg/bookmarks. The mapping is stored as {name: nodeid}.

    """

    def __init__(self, repo):

        self._repo = repo

        self._refmap = refmap = {}  # refspec: node

        self._nodemap = nodemap = {}  # node: sorted([refspec, ...])

        self._clean = True

        self._aclean = True

        nm = repo.changelog.nodemap

        try:

            with _getbkfile(repo) as bkfile:

                for line in bkfile:

                    line = line.strip()

                    if not line:

                        continue

                    try:

                        sha, refspec = line.split(' ', 1)

                        node = tonode(sha)

                        if node in nm:

                            refspec = encoding.tolocal(refspec)

                            refmap[refspec] = node

                            nrefs = nodemap.get(node)

                            if nrefs is None:

                                nodemap[node] = [refspec]

                            else:

                                nrefs.append(refspec)

                                if nrefs[-2] > refspec:

                                    # bookmarks weren't sorted before 4.5

                                    nrefs.sort()

                    except (TypeError, ValueError):

                        # TypeError:

                        # - bin(...)

                        # ValueError:

                        # - node in nm, for non-20-bytes entry

                        # - split(...), for string without ' '

                        bookmarkspath = '.hg/bookmarks'

                        if bookmarksinstore(repo):

                            bookmarkspath = '.hg/store/bookmarks'

        except IOError as inst:

            if inst.errno != errno.ENOENT:

                raise

        self._active = _readactive(repo, self)

    @property

    def active(self):

        return self._active

    @active.setter

    def active(self, mark):

        if mark is not None and mark not in self._refmap:

            raise AssertionError('bookmark %s does not exist!' % mark)

        self._active = mark

        self._aclean = False

    def __len__(self):

        return len(self._refmap)

    def __iter__(self):

        return iter(self._refmap)

    def iteritems(self):

        return self._refmap.iteritems()

    def items(self):

        return self._refmap.items()

    # TODO: maybe rename to allnames()?

    def keys(self):

        return self._refmap.keys()

    # TODO: maybe rename to allnodes()? but nodes would have to be deduplicated

    # could be self._nodemap.keys()

    def values(self):

        return self._refmap.values()

    def __contains__(self, mark):

        return mark in self._refmap

    def __getitem__(self, mark):

        return self._refmap[mark]

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

        return self._refmap.get(mark, default)

    def _set(self, mark, node):

        self._clean = False

        if mark in self._refmap:

            self._del(mark)

        self._refmap[mark] = node

        nrefs = self._nodemap.get(node)

        if nrefs is None:

            self._nodemap[node] = [mark]

        else:

            nrefs.append(mark)

            nrefs.sort()

    def _del(self, mark):

        self._clean = False

        node = self._refmap.pop(mark)

        nrefs = self._nodemap[node]

        if len(nrefs) == 1:

            assert nrefs[0] == mark

            del self._nodemap[node]

        else:

            nrefs.remove(mark)

    def names(self, node):

        """Return a sorted list of bookmarks pointing to the specified node"""

        return self._nodemap.get(node, [])

    def applychanges(self, repo, tr, changes):

        """Apply a list of changes to bookmarks

        """

        bmchanges = tr.changes.get('bookmarks')

        for name, node in changes:

            old = self._refmap.get(name)

            if node is None:

                self._del(name)

            else:

                self._set(name, node)

            if bmchanges is not None:

                # if a previous value exist preserve the "initial" value

                previous = bmchanges.get(name)

                if previous is not None:

                    old = previous[0]

                bmchanges[name] = (old, node)

        self._recordchange(tr)

    def _recordchange(self, tr):

        """record that bookmarks have been changed in a transaction

        The transaction is then responsible for updating the file content."""

        location = '' if bookmarksinstore(self._repo) else 'plain'

        tr.hookargs['bookmark_moved'] = '1'

    def _writerepo(self, repo):

        """Factored out for extensibility"""

        rbm = repo._bookmarks

        if rbm.active not in self._refmap:

            rbm.active = None

            rbm._writeactive()

        if bookmarksinstore(repo):

            vfs = repo.svfs

            lock = repo.lock()

        else:

            vfs = repo.vfs

            lock = repo.wlock()

        with lock:

            with vfs('bookmarks', 'w', atomictemp=True, checkambig=True) as f:

                self._write(f)

    def _writeactive(self):

        if self._aclean:

            return

        with self._repo.wlock():

            if self._active is not None:

                    f.write(encoding.fromlocal(self._active))

            else:

                self._repo.vfs.tryunlink('bookmarks.current')

        self._aclean = True

    def _write(self, fp):

        for name, node in sorted(self._refmap.iteritems()):

            fp.write("%s %s\n" % (hex(node), encoding.fromlocal(name)))

        self._clean = True

        self._repo.invalidatevolatilesets()

    def expandname(self, bname):

        if bname == '.':

            if self.active:

                return self.active

            else:

                raise error.RepoLookupError(_("no active bookmark"))

        return bname

    def checkconflict(self, mark, force=False, target=None):

        """check repo for a potential clash of mark with an existing bookmark,

        branch, or hash

        If target is supplied, then check that we are moving the bookmark

        forward.

        If force is supplied, then forcibly move the bookmark to a new commit

        regardless if it is a move forward.

        If divergent bookmark are to be deleted, they will be returned as list.

        """

        cur = self._repo['.'].node()

        if mark in self._refmap and not force:

            if target:

                if self._refmap[mark] == target and target == cur:

                    # re-activating a bookmark

                    return []

                rev = self._repo[target].rev()

                anc = self._repo.changelog.ancestors([rev])

                bmctx = self._repo[self[mark]]

                # allow resolving a single divergent bookmark even if moving

                # the bookmark across branches when a revision is specified

                # that contains a divergent bookmark

                if bmctx.rev() not in anc and target in divs:

                    return divergent2delete(self._repo, [target], mark)

                delbms = divergent2delete(self._repo, deletefrom, mark)

                if validdest(self._repo, bmctx, self._repo[target]):

                    self._repo.ui.status(

                    return delbms

            raise error.Abort(

        if len(mark) > 3 and not force:

            try:

                shadowhash = scmutil.isrevsymbol(self._repo, mark)

            except error.LookupError:  # ambiguous identifier

                shadowhash = False

            if shadowhash:

                self._repo.ui.warn(

        return []

def _readactive(repo, marks):

    """

    Get the active bookmark. We can have an active bookmark that updates

    itself as we commit. This function returns the name of that bookmark.

    It is stored in .hg/bookmarks.current

    """

    # No readline() in osutil.posixfile, reading everything is

    # cheap.

    content = repo.vfs.tryread('bookmarks.current')

    mark = encoding.tolocal((content.splitlines() or [''])[0])

    if mark == '' or mark not in marks:

        mark = None

    return mark

def activate(repo, mark):

    """

    Set the given bookmark to be 'active', meaning that this bookmark will

    follow new commits that are made.

    The name is recorded in .hg/bookmarks.current

    """

    repo._bookmarks.active = mark

    repo._bookmarks._writeactive()

def deactivate(repo):

    """

    Unset the active bookmark in this repository.

    """

    repo._bookmarks.active = None

    repo._bookmarks._writeactive()

def isactivewdirparent(repo):

    """

    Tell whether the 'active' bookmark (the one that follows new commits)

    points to one of the parents of the current working directory (wdir).

    While this is normally the case, it can on occasion be false; for example,

    immediately after a pull, the active bookmark can be moved to point

    to a place different than the wdir. This is solved by running `hg update`.

    """

    mark = repo._activebookmark

    marks = repo._bookmarks

    parents = [p.node() for p in repo[None].parents()]

def divergent2delete(repo, deletefrom, bm):

    """find divergent versions of bm on nodes in deletefrom.

    the list of bookmark to delete."""

    todelete = []

    marks = repo._bookmarks

    divergent = [b for b in marks if b.split('@', 1)[0] == bm.split('@', 1)[0]]

    for mark in divergent: