# convert.py Foreign SCM converter

#

# 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, incorporated herein by reference.

from common import NoRepo

from cvs import convert_cvs

from git import convert_git

from hg import convert_mercurial

from mercurial import hg, ui, util, commands

commands.norepo += " convert"

converters = [convert_cvs, convert_git, convert_mercurial]

def converter(ui, path, rev=None):

    if not os.path.isdir(path):

        raise util.Abort("%s: not a directory" % path)

    for c in converters:

        try:

            if rev:

                return c(ui, path, rev=rev)

            else:

                return c(ui, path)

        except NoRepo:

            pass

    raise util.Abort("%s: unknown repository type" % path)

class convert(object):

    def __init__(self, ui, source, dest, mapfile, opts):

        self.source = source

        self.dest = dest

        self.ui = ui

        self.opts = opts

        self.commitcache = {}

        self.mapfile = mapfile

        self.mapfilefd = None

        self.authors = {}

        self.authorfile = None

        self.map = {}

        try:

            origmapfile = open(self.mapfile, 'r')

            for l in origmapfile:

                sv, dv = l[:-1].split()

                self.map[sv] = dv

            origmapfile.close()

        except IOError:

            pass

        # Read first the dst author map if any

        authorfile = self.dest.authorfile()

        if authorfile and os.path.exists(authorfile):

            self.readauthormap(authorfile)

        # Extend/Override with new author map if necessary

        if opts.get('authors'):

            self.readauthormap(opts.get('authors'))

            self.authorfile = self.dest.authorfile()

    def walktree(self, heads):

        '''Return a mapping that identifies the uncommitted parents of every

        uncommitted changeset.'''

        visit = heads

        known = {}

        parents = {}

        while visit:

            n = visit.pop(0)

            if n in known or n in self.map: continue

            known[n] = 1

            self.commitcache[n] = self.source.getcommit(n)

            cp = self.commitcache[n].parents

            parents[n] = []

            for p in cp:

                parents[n].append(p)

                visit.append(p)

        return parents

    def toposort(self, parents):

        '''Return an ordering such that every uncommitted changeset is

        preceeded by all its uncommitted ancestors.'''

        visit = parents.keys()

        seen = {}

        children = {}

        while visit:

            n = visit.pop(0)

            if n in seen: continue

            seen[n] = 1

            # Ensure that nodes without parents are present in the 'children'

            # mapping.

            children.setdefault(n, [])

            for p in parents[n]:

                if not p in self.map:

                    visit.append(p)

                children.setdefault(p, []).append(n)

        s = []

        removed = {}

        visit = children.keys()

        while visit:

            n = visit.pop(0)

            if n in removed: continue

            dep = 0

            if n in parents:

                for p in parents[n]:

                    if p in self.map: continue

                    if p not in removed:

                        # we're still dependent

                        visit.append(n)

                        dep = 1

                        break

            if not dep:

                # all n's parents are in the list

                removed[n] = 1

                if n not in self.map:

                    s.append(n)

                if n in children:

                    for c in children[n]:

                        visit.insert(0, c)

        if self.opts.get('datesort'):

            depth = {}

            for n in s:

                depth[n] = 0

                pl = [p for p in self.commitcache[n].parents

                      if p not in self.map]

                if pl:

                    depth[n] = max([depth[p] for p in pl]) + 1

            s = [(depth[n], self.commitcache[n].date, n) for n in s]

            s.sort()

            s = [e[2] for e in s]

        return s

    def mapentry(self, src, dst):

        if self.mapfilefd is None:

            try:

                self.mapfilefd = open(self.mapfile, "a")

            except IOError, (errno, strerror):

                raise util.Abort("Could not open map file %s: %s, %s\n" % (self.mapfile, errno, strerror))

        self.map[src] = dst

        self.mapfilefd.write("%s %s\n" % (src, dst))

        self.mapfilefd.flush()

    def writeauthormap(self):

        authorfile = self.authorfile

        if authorfile:

           self.ui.status('Writing author map file %s\n' % authorfile)

           ofile = open(authorfile, 'w+')

           for author in self.authors:

               ofile.write("%s=%s\n" % (author, self.authors[author]))

           ofile.close()

    def readauthormap(self, authorfile):

        afile = open(authorfile, 'r')

        for line in afile:

            try:

                srcauthor = line.split('=')[0].strip()

                dstauthor = line.split('=')[1].strip()

                if srcauthor in self.authors and dstauthor != self.authors[srcauthor]:

                    self.ui.status(

                        'Overriding mapping for author %s, was %s, will be %s\n'

                        % (srcauthor, self.authors[srcauthor], dstauthor))

                else:

                    self.ui.debug('Mapping author %s to %s\n'

                                  % (srcauthor, dstauthor))

                    self.authors[srcauthor] = dstauthor

            except IndexError:

                self.ui.warn(

                    'Ignoring bad line in author file map %s: %s\n'

                    % (authorfile, line))

        afile.close()

    def copy(self, rev):

        c = self.commitcache[rev]

        files = self.source.getchanges(rev)

        for f, v in files:

            try:

                data = self.source.getfile(f, v)

            except IOError, inst:

                self.dest.delfile(f)

            else:

                e = self.source.getmode(f, v)

                self.dest.putfile(f, e, data)

        r = [self.map[v] for v in c.parents]

        f = [f for f, v in files]

        newnode = self.dest.putcommit(f, r, c)

        self.mapentry(rev, newnode)

    def convert(self):

        try:

            self.ui.status("scanning source...\n")

            heads = self.source.getheads()

            parents = self.walktree(heads)

            self.ui.status("sorting...\n")

            t = self.toposort(parents)

            num = len(t)

            c = None

            self.ui.status("converting...\n")

            for c in t:

                num -= 1

                desc = self.commitcache[c].desc

                if "\n" in desc:

                    desc = desc.splitlines()[0]

                author = self.commitcache[c].author

                author = self.authors.get(author, author)

                self.commitcache[c].author = author

                self.ui.status("%d %s\n" % (num, desc))

                self.copy(c)

            tags = self.source.gettags()

            ctags = {}

            for k in tags:

                v = tags[k]

                if v in self.map:

                    ctags[k] = self.map[v]

            if c and ctags:

                nrev = self.dest.puttags(ctags)

                # write another hash correspondence to override the previous

                # one so we don't end up with extra tag heads

                if nrev:

                    self.mapentry(c, nrev)

            self.writeauthormap()

        finally:

            self.cleanup()

    def cleanup(self):

       if self.mapfilefd:

           self.mapfilefd.close()

def _convert(ui, src, dest=None, mapfile=None, **opts):

    '''Convert a foreign SCM repository to a Mercurial one.

    Accepted source formats:

    - GIT

    - CVS

    Accepted destination formats:

    - Mercurial

    If no revision is given, all revisions will be converted. Otherwise,

    convert will only import up to the named revision (given in a format

    understood by the source).

    If destination isn't given, a new Mercurial repo named <src>-hg will

    be created. If <mapfile> isn't given, it will be put in a default

    location (<dest>/.hg/shamap by default)

    The <mapfile> is a simple text file that maps each source commit ID to

    the destination ID for that revision, like so:

    <source ID> <destination ID>

    If the file doesn't exist, it's automatically created.  It's updated

    on each commit copied, so convert-repo can be interrupted and can

    be run repeatedly to copy new commits.

    The [username mapping] file is a simple text file that maps each source

    commit author to a destination commit author. It is handy for source SCMs

    that use unix logins to identify authors (eg: CVS). One line per author

    mapping and the line format is:

    srcauthor=whatever string you want

    '''

    if not dest:

        dest = src + "-hg"

        ui.status("assuming destination %s\n" % dest)

    # Try to be smart and initalize things when required

    if os.path.isdir(dest):

        if len(os.listdir(dest)) > 0:

            try:

                hg.repository(ui, dest)

                ui.status("destination %s is a Mercurial repository\n" % dest)

            except hg.RepoError:

                raise util.Abort(

                    "destination directory %s is not empty.\n"

                    "Please specify an empty directory to be initialized\n"

                    "or an already initialized mercurial repository"

                    % dest)

        else:

            ui.status("initializing destination %s repository\n" % dest)

            hg.repository(ui, dest, create=True)

    elif os.path.exists(dest):

        raise util.Abort("destination %s exists and is not a directory" % dest)

    else:

        ui.status("initializing destination %s repository\n" % dest)

        hg.repository(ui, dest, create=True)

    destc = converter(ui, dest)

    if not hasattr(destc, "putcommit"):

        raise util.Abort("%s: can't write to this repo type" % src)

    if not mapfile:

        try:

            mapfile = destc.mapfile()

        except:

            mapfile = os.path.join(destc, "map")

    c = convert(ui, srcc, destc, mapfile, opts)

    c.convert()

cmdtable = {

    "convert":

        (_convert,

         [('A', 'authors', '', 'username mapping filename'),

          ('r', 'rev', '', 'import up to target revision REV'),

          ('', 'datesort', None, 'try to sort changesets by date')],

         'hg convert [OPTION]... SOURCE [DEST [MAPFILE]]'),

}