/brz/remove-bazaar

# Copyright (C) 2009 Canonical Ltd

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

"""Map from Git sha's to Bazaar objects."""

import bzrlib

from bzrlib import ui

from bzrlib.errors import NoSuchRevision

from bzrlib.plugins.git.mapping import (

    inventory_to_tree_and_blobs,

    revision_to_commit,

    )

from bzrlib.plugins.git.shamap import GitShaMap

from dulwich.objects import (

    Blob,

    )

class GitObjectConverter(object):

    def __init__(self, repository, mapping=None):

        self.repository = repository

        if mapping is None:

            self.mapping = self.repository.get_mapping()

        else:

            self.mapping = mapping

        self._idmap = GitShaMap(self.repository._transport)

    def _update_sha_map(self):

        all_revids = self.repository.all_revision_ids()

        graph = self.repository.get_graph()

        present_revids = set(self._idmap.revids())

        pb = ui.ui_factory.nested_progress_bar()

        try:

            for i, revid in enumerate(graph.iter_topo_order(all_revids)):

                if revid in present_revids:

                    continue

                pb.update("updating git map", i, len(all_revids))

                self._update_sha_map_revision(revid)

        finally:

            self._idmap.commit()

            pb.finished()

    def _update_sha_map_revision(self, revid):

        inv = self.repository.get_inventory(revid)

        objects = inventory_to_tree_and_blobs(self.repository, self.mapping, revid)

        for sha, o, path in objects:

            if path == "":

                tree_sha = sha

            ie = inv[inv.path2id(path)]

            if ie.kind in ("file", "symlink"):

                self._idmap.add_entry(sha, "blob", (ie.file_id, ie.revision))

            elif ie.kind == "directory":

                self._idmap.add_entry(sha, "tree", (path, ie.revision))

            else:

                raise AssertionError()

        rev = self.repository.get_revision(revid)

        commit_obj = revision_to_commit(rev, tree_sha, self._idmap._parent_lookup)

        self._idmap.add_entry(commit_obj.sha().hexdigest(), "commit", (revid, tree_sha))

    def _get_blob(self, fileid, revision):

        """Return a Git Blob object from a fileid and revision stored in bzr.

        :param fileid: File id of the text

        :param revision: Revision of the text

        """

        text = self.repository.texts.get_record_stream([(fileid, revision)], "unordered", True).next().get_bytes_as("fulltext")

        blob = Blob()

        blob._text = text

        return blob

    def _get_tree(self, path, revid):

        raise NotImplementedError(self._get_tree)

    def _get_commit(self, revid, tree_sha):

        rev = self.repository.get_revision(revid)

        return revision_to_commit(rev, tree_sha, self._idmap._parent_lookup)

    def __getitem__(self, sha):

        # See if sha is in map

        try:

            (type, type_data) = self._idmap.lookup_git_sha(sha)

        except KeyError:

            # if not, see if there are any unconverted revisions and add them 

            # to the map, search for sha in map again

            self._update_sha_map()

            (type, type_data) = self._idmap.lookup_git_sha(sha)

        # convert object to git object

        if type == "commit":

            return self._get_commit(*type_data)

        elif type == "blob":

            return self._get_blob(*type_data)

        elif type == "tree":

            return self._get_tree(*type_data)

        else:

            raise AssertionError("Unknown object type '%s'" % type)