# keyword.py - keyword expansion for mercurial

'''keyword expansion hack against the grain of a DSCM

This extension lets you expand RCS/CVS-like keywords in a Mercurial

repository.

There are many good reasons why this is not needed in a distributed

SCM, still it may be useful in very small projects based on single

files (like LaTeX packages), that are mostly addressed to an audience

not running a version control system.

Supported $keywords$ are:

    Revision: changeset id

    Author:   full username

    Date:     %a %b %d %H:%M:%S %Y %z $

    RCSFile:  basename,v

    Source:   /path/to/basename,v

    Id:       basename,v csetid %Y-%m-%d %H:%M:%S %s shortname

    Header:   /path/to/basename,v csetid %Y-%m-%d %H:%M:%S %s shortname

Simple setup in hgrc:

    # enable extension

    # keyword.py in hgext folder, specify full path otherwise

    hgext.keyword =

    # filename patterns for expansion are configured in this section

    [keyword]

    **.py = expand

    ...

'''

from mercurial.node import *

from mercurial import context, filelog, revlog, util

import os.path, re

re_kw = re.compile(

        r'\$(Id|Header|Author|Date|Revision|RCSFile|Source)[^$]*?\$')

def kwexpand(matchobj, repo, path, changeid=None, fileid=None, filelog=None):

    '''Called by kwrepo.commit and kwfilelog.read.

    Sets supported keywords as local variables and evaluates them to

    their expansion if matchobj is equal to string representation.'''

    c = context.filectx(repo, path,

            changeid=changeid, fileid=fileid, filelog=filelog)

    date = c.date()

    Revision = c.changectx()

    Author = c.user()

    RCSFile = os.path.basename(path)+',v'

    Source = repo.wjoin(path)+',v'

    Date = util.datestr(date=date)

    revdateauth = '%s %s %s' % (Revision,

            util.datestr(date=date, format=util.defaultdateformats[0]),

            util.shortuser(Author))

    Header = '%s %s' % (Source, revdateauth)

    Id = '%s %s' % (RCSFile, revdateauth)

    return '$%s: %s $' % (matchobj.group(1), eval(matchobj.group(1)))

def kwfmatches(ui, repo, files):

    '''Selects candidates for keyword substitution

    configured in keyword section in hgrc.'''

    files = [f for f in files if not f.startswith('.hg')]

    if not files:

        return []

    candidates = []

    fmatchers = [util.matcher(repo.root, '', [pat], [], [])[1]

            for pat, opt in ui.configitems('keyword')

            if opt == 'expand']

    for f in files:

        for mf in fmatchers:

            if mf(f):

                candidates.append(f)

                break

    return candidates

def reposetup(ui, repo):

    if not repo.local():

        return

    class kwrepo(repo.__class__):

        def file(self, f):

            if f[0] == '/':

                f = f[1:]

            return filelog.filelog(self.sopener, f, self, self.revlogversion)

        def commit(self, files=None, text="", user=None, date=None,

                match=util.always, force=False, lock=None, wlock=None,

                force_editor=False, p1=None, p2=None, extra={}):

            commit = []

            remove = []

            changed = []

            use_dirstate = (p1 is None) # not rawcommit

            extra = extra.copy()

            if use_dirstate:

                if files:

                    for f in files:

                        s = self.dirstate.state(f)

                        if s in 'nmai':

                            commit.append(f)

                        elif s == 'r':

                            remove.append(f)

                        else:

                            ui.warn(_("%s not tracked!\n") % f)

                else:

                    changes = self.status(match=match)[:5]

                    modified, added, removed, deleted, unknown = changes

                    commit = modified + added

                    remove = removed

            else:

                commit = files

            if use_dirstate:

                p1, p2 = self.dirstate.parents()

                update_dirstate = True

            else:

                p1, p2 = p1, p2 or nullid

                update_dirstate = (self.dirstate.parents()[0] == p1)

            c1 = self.changelog.read(p1)

            c2 = self.changelog.read(p2)

            m1 = self.manifest.read(c1[0]).copy()

            m2 = self.manifest.read(c2[0])

            if use_dirstate:

                branchname = self.workingctx().branch()

                try:

                    branchname = branchname.decode('UTF-8').encode('UTF-8')

                except UnicodeDecodeError:

                    raise util.Abort(_('branch name not in UTF-8!'))

            else:

                branchname = ""

            if use_dirstate:

                oldname = c1[5].get("branch", "") # stored in UTF-8

                if not commit and not remove and not force and p2 == nullid and \

                       branchname == oldname:

                    ui.status(_("nothing changed\n"))

                    return None

            xp1 = hex(p1)

            if p2 == nullid: xp2 = ''

            else: xp2 = hex(p2)

            self.hook("precommit", throw=True, parent1=xp1, parent2=xp2)

            if not wlock:

                wlock = self.wlock()

            if not lock:

                lock = self.lock()

            tr = self.transaction()

            # check in files

            new = {}

            linkrev = self.changelog.count()

            commit.sort()

            for f in commit:

                ui.note(f + "\n")

                try:

                    new[f] = self.filecommit(f, m1, m2, linkrev, tr, changed)

                    if use_dirstate:

                        ui.warn(_("trouble committing %s!\n") % f)

                        raise

                    else:

                        remove.append(f)

            # update manifest

            m1.update(new)

            remove.sort()

            for f in remove:

                if f in m1:

                    del m1[f]

            # add changeset

            new = new.keys()

            new.sort()

            user = user or ui.username()

            if not text or force_editor:

                edittext = []

                if text:

                    edittext.append(text)

                edittext.append("")

                edittext.append("HG: user: %s" % user)

                if p2 != nullid:

                    edittext.append("HG: branch merge")

                edittext.extend(["HG: changed %s" % f for f in changed])

                if not changed and not remove:

                    edittext.append("HG: no files changed")

                edittext.append("")

                # run editor in the repository root

                olddir = os.getcwd()

                os.chdir(self.root)

                text = ui.edit("\n".join(edittext), user)

                os.chdir(olddir)

            lines = [line.rstrip() for line in text.rstrip().splitlines()]

            while lines and not lines[0]:

                del lines[0]

            if not lines:

                return None

            text = '\n'.join(lines)

            if branchname:

                extra["branch"] = branchname

                                   user, date, extra)

            self.hook('pretxncommit', throw=True, node=hex(n), parent1=xp1,

                      parent2=xp2)

            # substitute keywords

            for f in kwfmatches(ui, self, changed):

                data = self.wfile(f).read()

                if not util.binary(data):

                    data, kwct = re_kw.subn(lambda m:

                            kwexpand(m, self, f, changeid=hex(n)), data)

                    if kwct:

                        ui.debug(_('overwriting %s expanding keywords\n' % f))

                        self.wfile(f, 'w').write(data)

            tr.close()

            if use_dirstate or update_dirstate:

                self.dirstate.setparents(n)

                if use_dirstate:

                    self.dirstate.update(new, "n")

                    self.dirstate.forget(removed)

            self.hook("commit", node=hex(n), parent1=xp1, parent2=xp2)

            return n

    class kwfilelog(filelog.filelog):

        def __init__(self, opener, path, repo,

                     defversion=revlog.REVLOG_DEFAULT_VERSION):

            super(kwfilelog, self).__init__(opener, path, defversion)

            self._repo = repo

            self._path = path

        def read(self, node):

            data = super(kwfilelog, self).read(node)

                return re_kw.sub(lambda m:

                        kwexpand(m, self._repo, self._path,

                            fileid=node, filelog=self), data)

            return data

        def cmp(self, node, text):

                text = re_kw.sub(r'$\1$', text)

            return super(kwfilelog, self).cmp(node, text)

    filelog.filelog = kwfilelog

    repo.__class__ = kwrepo