/brz/remove-bazaar

# Copyright (C) 2008 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

from bzrlib import osutils, urlutils

from bzrlib.errors import InvalidRevisionId

from bzrlib.inventory import Inventory

from bzrlib.repository import InterRepository

from bzrlib.trace import info

from bzrlib.plugins.git import git

from bzrlib.plugins.git.repository import LocalGitRepository, GitRepository, GitFormat

from bzrlib.plugins.git.remote import RemoteGitRepository

from dulwich.objects import Commit

from cStringIO import StringIO

class BzrFetchGraphWalker(object):

    def __init__(self, repository, mapping):

        self.repository = repository

        self.mapping = mapping

        self.done = set()

        self.heads = set(repository.all_revision_ids())

        self.parents = {}

    def ack(self, sha):

        revid = self.mapping.revision_id_foreign_to_bzr(sha)

        self.remove(revid)

    def remove(self, revid):

        self.done.add(revid)

        if ref in self.heads:

            self.heads.remove(revid)

        if revid in self.parents:

            for p in self.parents[revid]:

                self.remove(p)

    def next(self):

        while self.heads:

            ret = self.heads.pop()

            ps = self.repository.get_parent_map([ret])[ret]

            self.parents[ret] = ps

            self.heads.update([p for p in ps if not p in self.done])

            try:

                self.done.add(ret)

                return self.mapping.revision_id_bzr_to_foreign(ret)

            except InvalidRevisionId:

                pass

        return None

def import_git_blob(repo, mapping, path, blob, inv):

    """Import a git blob object into a bzr repository.

    :param repo: bzr repository

    :param path: Path in the tree

    :param blob: A git blob

    """

    file_id = mapping.generate_file_id(path)

    repo.texts.add_lines((file_id, blob.id),

        [], #FIXME 

        osutils.split_lines(blob.data))

    ie = inv.add_path(path, "file", file_id)

def import_git_tree(repo, mapping, path, tree, inv, lookup_object):

    """Import a git tree object into a bzr repository.

    :param repo: A Bzr repository object

    :param path: Path in the tree

    :param tree: A git tree object

    :param inv: Inventory object

    """

    file_id = mapping.generate_file_id(path)

    repo.texts.add_lines((file_id, tree.id),

        [], #FIXME 

        [])

    inv.add_path(path, "directory", file_id)

    for mode, name, hexsha in tree.entries():

        entry_kind = (mode & 0700000) / 0100000

        basename = name.decode("utf-8")

        if path == "":

            child_path = name

        else:

            child_path = urlutils.join(path, name)

        if entry_kind == 0:

            tree = lookup_object(hexsha)

            import_git_tree(repo, mapping, child_path, tree, inv, lookup_object)

        elif entry_kind == 1:

            blob = lookup_object(hexsha)

            import_git_blob(repo, mapping, child_path, blob, inv)

        else:

            raise AssertionError("Unknown blob kind, perms=%r." % (mode,))

def import_git_objects(repo, mapping, object_iter):

    """Import a set of git objects into a bzr repository.

    :param repo: Bazaar repository

    :param mapping: Mapping to use

    :param object_iter: Iterator over Git objects.

    """

    # TODO: a more (memory-)efficient implementation of this

    objects = {}

    for o in object_iter:

        objects[o.id] = o

    root_trees = {}

    # Find and convert commit objects

    for o in objects.itervalues():

        if isinstance(o, Commit):

            rev = mapping.import_commit(o)

            root_trees[rev] = objects[o.tree]

    # Create the inventory objects

    for rev, root_tree in root_trees.iteritems():

        # We have to do this here, since we have to walk the tree and 

        # we need to make sure to import the blobs / trees with the riht 

        # path; this may involve adding them more than once.

        inv = Inventory()

        inv.revision_id = rev.revision_id

        def lookup_object(sha):

            if sha in objects:

                return objects[sha]

            return reconstruct_git_object(repo, mapping, sha)

        import_git_tree(repo, mapping, "", root_tree, inv, lookup_object)

        repo.add_revision(rev.revision_id, rev, inv)

def reconstruct_git_commit(repo, rev):

    raise NotImplementedError(self.reconstruct_git_commit)

def reconstruct_git_object(repo, mapping, sha):

    # Commit

    revid = mapping.revision_id_foreign_to_bzr(sha)

    try:

        rev = repo.get_revision(revid)

    except NoSuchRevision:

        pass

    else:

        return reconstruct_git_commit(rev)

    # TODO: Tree

    # TODO: Blob

    raise KeyError("No such object %s" % sha)

class InterGitRepository(InterRepository):

    _matching_repo_format = GitFormat()

    @staticmethod

    def _get_repo_format_to_test():

        return None

    def copy_content(self, revision_id=None, pb=None):

        """See InterRepository.copy_content."""

        self.fetch(revision_id, pb, find_ghosts=False)

    def fetch(self, revision_id=None, pb=None, find_ghosts=False, 

              mapping=None):

        if mapping is None:

            mapping = self.source.get_mapping()

        def progress(text):

            if pb is not None:

                pb.note("git: %s" % text)

            else:

                info("git: %s" % text)

        def determine_wants(heads):

            if revision_id is None:

                ret = heads.values()

            else:

                ret = [mapping.revision_id_bzr_to_foreign(revision_id)]

            return [rev for rev in ret if not self.target.has_revision(mapping.revision_id_foreign_to_bzr(rev))]

        graph_walker = BzrFetchGraphWalker(self.target, mapping)

        self.target.lock_write()

        try:

            self.target.start_write_group()

            try:

                import_git_objects(self.target, mapping,

                    iter(self.source.fetch_objects(determine_wants, graph_walker, 

                        progress)))

            finally:

                self.target.commit_write_group()

        finally:

            self.target.unlock()

    @staticmethod

    def is_compatible(source, target):

        """Be compatible with GitRepository."""

        # FIXME: Also check target uses VersionedFile

        return (isinstance(source, LocalGitRepository) and 

                target.supports_rich_root())