# filelog.py - file history class for mercurial

#

# Copyright 2005-2007 Olivia Mackall <olivia@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

from .i18n import _

from .node import nullrev

from . import (

    error,

    revlog,

)

from .interfaces import (

    repository,

    util as interfaceutil,

)

from .utils import storageutil

from .revlogutils import (

    constants as revlog_constants,

)

@interfaceutil.implementer(repository.ifilestorage)

class filelog(object):

    def __init__(self, opener, path):

        self._revlog = revlog.revlog(

            opener,

            # XXX should use the unencoded path

            target=(revlog_constants.KIND_FILELOG, path),

            indexfile=b'/'.join((b'data', path + b'.i')),

            censorable=True,

        )

        # Full name of the user visible file, relative to the repository root.

        # Used by LFS.

        self._revlog.filename = path

        self.nullid = self._revlog.nullid

    def __len__(self):

        return len(self._revlog)

    def __iter__(self):

        return self._revlog.__iter__()

    def hasnode(self, node):

        if node in (self.nullid, nullrev):

            return False

        try:

            self._revlog.rev(node)

            return True

        except (TypeError, ValueError, IndexError, error.LookupError):

            return False

    def revs(self, start=0, stop=None):

        return self._revlog.revs(start=start, stop=stop)

    def parents(self, node):

        return self._revlog.parents(node)

    def parentrevs(self, rev):

        return self._revlog.parentrevs(rev)

    def rev(self, node):

        return self._revlog.rev(node)

    def node(self, rev):

        return self._revlog.node(rev)

    def lookup(self, node):

        return storageutil.fileidlookup(

            self._revlog, node, self._revlog.indexfile

        )

    def linkrev(self, rev):

        return self._revlog.linkrev(rev)

    def commonancestorsheads(self, node1, node2):

        return self._revlog.commonancestorsheads(node1, node2)

    # Used by dagop.blockdescendants().

    def descendants(self, revs):

        return self._revlog.descendants(revs)

    def heads(self, start=None, stop=None):

        return self._revlog.heads(start, stop)

    # Used by hgweb, children extension.

    def children(self, node):

        return self._revlog.children(node)

    def iscensored(self, rev):

        return self._revlog.iscensored(rev)

    def revision(self, node, _df=None, raw=False):

        return self._revlog.revision(node, _df=_df, raw=raw)

    def rawdata(self, node, _df=None):

        return self._revlog.rawdata(node, _df=_df)

    def emitrevisions(

        self,

        nodes,

        nodesorder=None,

        revisiondata=False,

        assumehaveparentrevisions=False,

        deltamode=repository.CG_DELTAMODE_STD,

        sidedata_helpers=None,

    ):

        return self._revlog.emitrevisions(

            nodes,

            nodesorder=nodesorder,

            revisiondata=revisiondata,

            assumehaveparentrevisions=assumehaveparentrevisions,

            deltamode=deltamode,

            sidedata_helpers=sidedata_helpers,

        )

    def addrevision(

        self,

        revisiondata,

        transaction,

        linkrev,

        p1,

        p2,

        node=None,

        flags=revlog.REVIDX_DEFAULT_FLAGS,

        cachedelta=None,

    ):

        return self._revlog.addrevision(

            revisiondata,

            transaction,

            linkrev,

            p1,

            p2,

            node=node,

            flags=flags,

            cachedelta=cachedelta,

        )

    def addgroup(

        self,

        deltas,

        linkmapper,

        transaction,

        addrevisioncb=None,

        duplicaterevisioncb=None,

        maybemissingparents=False,

    ):

        if maybemissingparents:

            raise error.Abort(

                _(

                    b'revlog storage does not support missing '

                    b'parents write mode'

                )

            )

        return self._revlog.addgroup(

            deltas,

            linkmapper,

            transaction,

            addrevisioncb=addrevisioncb,

            duplicaterevisioncb=duplicaterevisioncb,

        )

    def getstrippoint(self, minlink):

        return self._revlog.getstrippoint(minlink)

    def strip(self, minlink, transaction):

        return self._revlog.strip(minlink, transaction)

    def censorrevision(self, tr, node, tombstone=b''):

        return self._revlog.censorrevision(tr, node, tombstone=tombstone)

    def files(self):

        return self._revlog.files()

    def read(self, node):

        return storageutil.filtermetadata(self.revision(node))

    def add(self, text, meta, transaction, link, p1=None, p2=None):

        if meta or text.startswith(b'\1\n'):

            text = storageutil.packmeta(meta, text)

        rev = self.addrevision(text, transaction, link, p1, p2)

        return self.node(rev)

    def renamed(self, node):

        return storageutil.filerevisioncopied(self, node)

    def size(self, rev):

        """return the size of a given revision"""

        # for revisions with renames, we have to go the slow way

        node = self.node(rev)

        if self.renamed(node):

            return len(self.read(node))

        if self.iscensored(rev):

            return 0

        # XXX if self.read(node).startswith("\1\n"), this returns (size+4)

        return self._revlog.size(rev)

    def cmp(self, node, text):

        """compare text with a given file revision

        returns True if text is different than what is stored.

        """

        return not storageutil.filedataequivalent(self, node, text)

    def verifyintegrity(self, state):

        return self._revlog.verifyintegrity(state)

    def storageinfo(

        self,

        exclusivefiles=False,

        sharedfiles=False,

        revisionscount=False,

        trackedsize=False,

        storedsize=False,

    ):

        return self._revlog.storageinfo(

            exclusivefiles=exclusivefiles,

            sharedfiles=sharedfiles,

            revisionscount=revisionscount,

            trackedsize=trackedsize,

            storedsize=storedsize,

        )

    # TODO these aren't part of the interface and aren't internal methods.

    # Callers should be fixed to not use them.

    # Used by bundlefilelog, unionfilelog.

    @property

    def indexfile(self):

        return self._revlog.indexfile

    @indexfile.setter

    def indexfile(self, value):

        self._revlog.indexfile = value

    # Used by repo upgrade.

    def clone(self, tr, destrevlog, **kwargs):

        if not isinstance(destrevlog, filelog):

            raise error.ProgrammingError(b'expected filelog to clone()')

        return self._revlog.clone(tr, destrevlog._revlog, **kwargs)

class narrowfilelog(filelog):

    """Filelog variation to be used with narrow stores."""

    def __init__(self, opener, path, narrowmatch):

        super(narrowfilelog, self).__init__(opener, path)

        self._narrowmatch = narrowmatch

    def renamed(self, node):

        res = super(narrowfilelog, self).renamed(node)

        # Renames that come from outside the narrowspec are problematic

        # because we may lack the base text for the rename. This can result

        # in code attempting to walk the ancestry or compute a diff

        # encountering a missing revision. We address this by silently

        # removing rename metadata if the source file is outside the

        # narrow spec.

        #

        # A better solution would be to see if the base revision is available,

        # rather than assuming it isn't.

        #

        # An even better solution would be to teach all consumers of rename

        # metadata that the base revision may not be available.

        #

        # TODO consider better ways of doing this.

        if res and not self._narrowmatch(res[0]):

            return None

        return res

    def size(self, rev):

        # Because we have a custom renamed() that may lie, we need to call

        # the base renamed() to report accurate results.

        node = self.node(rev)

        if super(narrowfilelog, self).renamed(node):

            return len(self.read(node))

        else:

            return super(narrowfilelog, self).size(rev)

    def cmp(self, node, text):

        # We don't call `super` because narrow parents can be buggy in case of a

        # ambiguous dirstate. Always take the slow path until there is a better

        # fix, see issue6150.

        # Censored files compare against the empty file.

        if self.iscensored(self.rev(node)):

            return text != b''

        return self.read(node) != text