# context.py - changeset and file context objects for mercurial

#

# Copyright 2006, 2007 Matt Mackall <mpm@selenic.com>

#

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

# of the GNU General Public License, incorporated herein by reference.

from node import nullid, nullrev, short, hex

from i18n import _

import ancestor, bdiff, revlog, util, os, errno

class propertycache(object):

    def __init__(self, func):

        self.func = func

        self.name = func.__name__

    def __get__(self, obj, type=None):

        result = self.func(obj)

        setattr(obj, self.name, result)

        return result

class changectx(object):

    """A changecontext object makes access to data related to a particular

    changeset convenient."""

    def __init__(self, repo, changeid=''):

        """changeid is a revision number, node, or tag"""

        if changeid == '':

            changeid = '.'

        self._repo = repo

        if isinstance(changeid, (long, int)):

            self._rev = changeid

            self._node = self._repo.changelog.node(changeid)

        else:

            self._node = self._repo.lookup(changeid)

            self._rev = self._repo.changelog.rev(self._node)

    def __str__(self):

        return short(self.node())

    def __int__(self):

        return self.rev()

    def __repr__(self):

        return "<changectx %s>" % str(self)

    def __hash__(self):

        try:

            return hash(self._rev)

        except AttributeError:

            return id(self)

    def __eq__(self, other):

        try:

            return self._rev == other._rev

        except AttributeError:

            return False

    def __ne__(self, other):

        return not (self == other)

    def __nonzero__(self):

        return self._rev != nullrev

    def _changeset(self):

        return self._repo.changelog.read(self.node())

    _changeset = propertycache(_changeset)

    def _manifest(self):

        return self._repo.manifest.read(self._changeset[0])

    _manifest = propertycache(_manifest)

    def _manifestdelta(self):

        return self._repo.manifest.readdelta(self._changeset[0])

    _manifestdelta = propertycache(_manifestdelta)

    def _parents(self):

        p = self._repo.changelog.parentrevs(self._rev)

        if p[1] == nullrev:

            p = p[:-1]

        return [changectx(self._repo, x) for x in p]

    _parents = propertycache(_parents)

    def __contains__(self, key):

        return key in self._manifest

    def __getitem__(self, key):

        return self.filectx(key)

    def __iter__(self):

        for f in util.sort(self._manifest):

            yield f

    def changeset(self): return self._changeset

    def manifest(self): return self._manifest

    def rev(self): return self._rev

    def node(self): return self._node

    def hex(self): return hex(self._node)

    def user(self): return self._changeset[1]

    def date(self): return self._changeset[2]

    def files(self): return self._changeset[3]

    def description(self): return self._changeset[4]

    def branch(self): return self._changeset[5].get("branch")

    def extra(self): return self._changeset[5]

    def tags(self): return self._repo.nodetags(self._node)

    def parents(self):

        """return contexts for each parent changeset"""

        return self._parents

    def children(self):

        """return contexts for each child changeset"""

        c = self._repo.changelog.children(self._node)

        return [changectx(self._repo, x) for x in c]

    def ancestors(self):

        for a in self._repo.changelog.ancestors(self._rev):

            yield changectx(self._repo, a)

    def descendants(self):

        for d in self._repo.changelog.descendants(self._rev):

            yield changectx(self._repo, d)

    def _fileinfo(self, path):

        if '_manifest' in self.__dict__:

            try:

                return self._manifest[path], self._manifest.flags(path)

            except KeyError:

                raise revlog.LookupError(self._node, path,

                                         _('not found in manifest'))

        if '_manifestdelta' in self.__dict__ or path in self.files():

            if path in self._manifestdelta:

                return self._manifestdelta[path], self._manifestdelta.flags(path)

        node, flag = self._repo.manifest.find(self._changeset[0], path)

        if not node:

            raise revlog.LookupError(self._node, path,

                                     _('not found in manifest'))

        return node, flag

    def filenode(self, path):

        return self._fileinfo(path)[0]

    def flags(self, path):

        try:

            return self._fileinfo(path)[1]

        except revlog.LookupError:

            return ''

    def filectx(self, path, fileid=None, filelog=None):

        """get a file context from this changeset"""

        if fileid is None:

            fileid = self.filenode(path)

        return filectx(self._repo, path, fileid=fileid,

                       changectx=self, filelog=filelog)

    def ancestor(self, c2):

        """

        return the ancestor context of self and c2

        """

        n = self._repo.changelog.ancestor(self._node, c2._node)

        return changectx(self._repo, n)

    def walk(self, match):

        fdict = dict.fromkeys(match.files())

        # for dirstate.walk, files=['.'] means "walk the whole tree".

        # follow that here, too

        fdict.pop('.', None)

        for fn in self:

            for ffn in fdict:

                # match if the file is the exact name or a directory

                if ffn == fn or fn.startswith("%s/" % ffn):

                    del fdict[ffn]

                    break

            if match(fn):

                yield fn

        for fn in util.sort(fdict):

            if match.bad(fn, 'No such file in rev ' + str(self)) and match(fn):

                yield fn

class filectx(object):

    """A filecontext object makes access to data related to a particular

       filerevision convenient."""

    def __init__(self, repo, path, changeid=None, fileid=None,

                 filelog=None, changectx=None):

        """changeid can be a changeset revision, node, or tag.

           fileid can be a file revision or node."""

        self._repo = repo

        self._path = path

        assert (changeid is not None

                or fileid is not None

                or changectx is not None)

        if filelog:

            self._filelog = filelog

        if changeid is not None:

            self._changeid = changeid

        if changectx is not None:

            self._changectx = changectx

        if fileid is not None:

            self._fileid = fileid

    def _changectx(self):

        return changectx(self._repo, self._changeid)

    _changectx = propertycache(_changectx)

    def _filelog(self):

        return self._repo.file(self._path)

    _filelog = propertycache(_filelog)

    def _changeid(self):

        if '_changectx' in self.__dict__:

            return self._changectx.rev()

        else:

            return self._filelog.linkrev(self._filerev)

    _changeid = propertycache(_changeid)

    def _filenode(self):

        if '_fileid' in self.__dict__:

            return self._filelog.lookup(self._fileid)

        else:

            return self._changectx.filenode(self._path)

    _filenode = propertycache(_filenode)

    def _filerev(self):

        return self._filelog.rev(self._filenode)

    _filerev = propertycache(_filerev)

    def _repopath(self):

        return self._path

    _repopath = propertycache(_repopath)

    def __nonzero__(self):

        try:

            n = self._filenode

            return True

        except revlog.LookupError:

            # file is missing

            return False

    def __str__(self):

        return "%s@%s" % (self.path(), short(self.node()))

    def __repr__(self):

        return "<filectx %s>" % str(self)

    def __hash__(self):

        try:

            return hash((self._path, self._fileid))

        except AttributeError:

            return id(self)

    def __eq__(self, other):

        try:

            return (self._path == other._path

                    and self._fileid == other._fileid)

        except AttributeError:

            return False

    def __ne__(self, other):

        return not (self == other)

    def filectx(self, fileid):

        '''opens an arbitrary revision of the file without

        opening a new filelog'''

        return filectx(self._repo, self._path, fileid=fileid,

                       filelog=self._filelog)

    def filerev(self): return self._filerev

    def filenode(self): return self._filenode

    def flags(self): return self._changectx.flags(self._path)

    def filelog(self): return self._filelog

    def rev(self):

        if '_changectx' in self.__dict__:

            return self._changectx.rev()

        if '_changeid' in self.__dict__:

            return self._changectx.rev()

        return self._filelog.linkrev(self._filerev)

    def linkrev(self): return self._filelog.linkrev(self._filerev)

    def node(self): return self._changectx.node()

    def user(self): return self._changectx.user()

    def date(self): return self._changectx.date()

    def files(self): return self._changectx.files()

    def description(self): return self._changectx.description()

    def branch(self): return self._changectx.branch()

    def manifest(self): return self._changectx.manifest()

    def changectx(self): return self._changectx

    def data(self): return self._filelog.read(self._filenode)

    def path(self): return self._path

    def size(self): return self._filelog.size(self._filerev)

    def cmp(self, text): return self._filelog.cmp(self._filenode, text)

    def renamed(self):

        """check if file was actually renamed in this changeset revision

        If rename logged in file revision, we report copy for changeset only

        if file revisions linkrev points back to the changeset in question

        or both changeset parents contain different file revisions.

        """

        renamed = self._filelog.renamed(self._filenode)

        if not renamed:

            return renamed

        if self.rev() == self.linkrev():

            return renamed

        name = self.path()

        fnode = self._filenode

        for p in self._changectx.parents():

            try:

                if fnode == p.filenode(name):

                    return None

            except revlog.LookupError:

                pass

        return renamed

    def parents(self):

        p = self._path

        fl = self._filelog

        pl = [(p, n, fl) for n in self._filelog.parents(self._filenode)]

        r = self._filelog.renamed(self._filenode)

        if r:

            pl[0] = (r[0], r[1], None)

        return [filectx(self._repo, p, fileid=n, filelog=l)

                for p,n,l in pl if n != nullid]

    def children(self):

        # hard for renames

        c = self._filelog.children(self._filenode)

        return [filectx(self._repo, self._path, fileid=x,

                        filelog=self._filelog) for x in c]

    def annotate(self, follow=False, linenumber=None):

        '''returns a list of tuples of (ctx, line) for each line

        in the file, where ctx is the filectx of the node where

        that line was last changed.

        This returns tuples of ((ctx, linenumber), line) for each line,

        if "linenumber" parameter is NOT "None".

        In such tuples, linenumber means one at the first appearance

        in the managed file.

        To reduce annotation cost,

        this returns fixed value(False is used) as linenumber,

        if "linenumber" parameter is "False".'''

        def decorate_compat(text, rev):

            return ([rev] * len(text.splitlines()), text)

        def without_linenumber(text, rev):

            return ([(rev, False)] * len(text.splitlines()), text)

        def with_linenumber(text, rev):

            size = len(text.splitlines())

            return ([(rev, i) for i in xrange(1, size + 1)], text)

        decorate = (((linenumber is None) and decorate_compat) or

                    (linenumber and with_linenumber) or

                    without_linenumber)

        def pair(parent, child):

            for a1, a2, b1, b2 in bdiff.blocks(parent[1], child[1]):

                child[0][b1:b2] = parent[0][a1:a2]

            return child

        getlog = util.cachefunc(lambda x: self._repo.file(x))

        def getctx(path, fileid):

            log = path == self._path and self._filelog or getlog(path)

            return filectx(self._repo, path, fileid=fileid, filelog=log)

        getctx = util.cachefunc(getctx)

        def parents(f):

            # we want to reuse filectx objects as much as possible

            p = f._path

            if f._filerev is None: # working dir

                pl = [(n.path(), n.filerev()) for n in f.parents()]

            else:

                pl = [(p, n) for n in f._filelog.parentrevs(f._filerev)]

            if follow:

                r = f.renamed()

                if r:

                    pl[0] = (r[0], getlog(r[0]).rev(r[1]))

            return [getctx(p, n) for p, n in pl if n != nullrev]

        # use linkrev to find the first changeset where self appeared

        if self.rev() != self.linkrev():

            base = self.filectx(self.filerev())

        else:

            base = self

        # find all ancestors

        needed = {base: 1}

        visit = [base]

        files = [base._path]

        while visit:

            f = visit.pop(0)

            for p in parents(f):

                if p not in needed:

                    needed[p] = 1

                    visit.append(p)

                    if p._path not in files:

                        files.append(p._path)

                else:

                    # count how many times we'll use this

                    needed[p] += 1

        # sort by revision (per file) which is a topological order

        visit = []

        for f in files:

            fn = [(n.rev(), n) for n in needed if n._path == f]

            visit.extend(fn)

        hist = {}

        for r, f in util.sort(visit):

            curr = decorate(f.data(), f)

            for p in parents(f):

                if p != nullid:

                    curr = pair(hist[p], curr)

                    # trim the history of unneeded revs

                    needed[p] -= 1

                    if not needed[p]:

                        del hist[p]

            hist[f] = curr

        return zip(hist[f][0], hist[f][1].splitlines(1))

    def ancestor(self, fc2):

        """

        find the common ancestor file context, if any, of self, and fc2

        """

        acache = {}

        # prime the ancestor cache for the working directory

        for c in (self, fc2):

            if c._filerev == None:

                pl = [(n.path(), n.filenode()) for n in c.parents()]

                acache[(c._path, None)] = pl

        flcache = {self._repopath:self._filelog, fc2._repopath:fc2._filelog}

        def parents(vertex):

            if vertex in acache:

                return acache[vertex]

            f, n = vertex

            if f not in flcache:

                flcache[f] = self._repo.file(f)

            fl = flcache[f]

            pl = [(f, p) for p in fl.parents(n) if p != nullid]

            re = fl.renamed(n)

            if re:

                pl.append(re)

            acache[vertex] = pl

            return pl

        a, b = (self._path, self._filenode), (fc2._path, fc2._filenode)

        v = ancestor.ancestor(a, b, parents)

        if v:

            f, n = v

            return filectx(self._repo, f, fileid=n, filelog=flcache[f])

        return None

class workingctx(changectx):

    """A workingctx object makes access to data related to

    the current working directory convenient.

    parents - a pair of parent nodeids, or None to use the dirstate.

    date - any valid date string or (unixtime, offset), or None.

    user - username string, or None.

    extra - a dictionary of extra values, or None.

    changes - a list of file lists as returned by localrepo.status()

               or None to use the repository status.

    """

    def __init__(self, repo, parents=None, text="", user=None, date=None,

                 extra=None, changes=None):

        self._repo = repo

        self._rev = None

        self._node = None

        self._text = text