/brz/remove-bazaar

# Copyright (C) 2007 Canonical Ltd

# Copyright (C) 2008-2009 Jelmer Vernooij <jelmer@samba.org>

# Copyright (C) 2008 John Carr

#

# 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

"""Converters, etc for going between Bazaar and Git ids."""

import stat

from bzrlib import (

    bencode,

    errors,

    foreign,

    osutils,

    trace,

    urlutils,

    )

from bzrlib.inventory import (

    ROOT_ID,

    )

from bzrlib.foreign import (

    ForeignVcs, 

    VcsMappingRegistry, 

    ForeignRevision,

    )

DEFAULT_FILE_MODE = stat.S_IFREG | 0644

def escape_file_id(file_id):

    return file_id.replace('_', '__').replace(' ', '_s')

def unescape_file_id(file_id):

    ret = []

    i = 0

    while i < len(file_id):

        if file_id[i] != '_':

            ret.append(file_id[i])

        else:

            if file_id[i+1] == '_':

                ret.append("_")

            elif file_id[i+1] == 's':

                ret.append(" ")

            else:

                raise AssertionError("unknown escape character %s" % file_id[i+1])

            i += 1

        i += 1

    return "".join(ret)

def fix_person_identifier(text):

    if "<" in text and ">" in text:

        return text

    return "%s <%s>" % (text, text)

def warn_escaped(commit, num_escaped):

    trace.warning("Escaped %d XML-invalid characters in %s. Will be unable "

                  "to regenerate the SHA map.", num_escaped, commit)

def warn_unusual_mode(commit, path, mode):

    trace.mutter("Unusual file mode %o for %s in %s. Storing as revision property. ",

                 mode, path, commit)

def squash_revision(target_repo, rev):

    """Remove characters that can't be stored from a revision, if necessary.

    :param target_repo: Repository in which the revision will be stored

    :param rev: Revision object, will be modified in-place

    """

    if not getattr(target_repo._serializer, "squashes_xml_invalid_characters", True):

        return

    from bzrlib.xml_serializer import escape_invalid_chars

    rev.message, num_escaped = escape_invalid_chars(rev.message)

    if num_escaped:

        warn_escaped(rev.foreign_revid, num_escaped)

    if 'author' in rev.properties:

        rev.properties['author'], num_escaped = escape_invalid_chars(

            rev.properties['author'])

        if num_escaped:

            warn_escaped(rev.foreign_revid, num_escaped)

    rev.committer, num_escaped = escape_invalid_chars(rev.committer)

    if num_escaped:

        warn_escaped(rev.foreign_revid, num_escaped)

class BzrGitMapping(foreign.VcsMapping):

    """Class that maps between Git and Bazaar semantics."""

    experimental = False

    def __init__(self):

        super(BzrGitMapping, self).__init__(foreign_git)

    def __eq__(self, other):

        return type(self) == type(other) and self.revid_prefix == other.revid_prefix

    @classmethod

    def revision_id_foreign_to_bzr(cls, git_rev_id):

        """Convert a git revision id handle to a Bazaar revision id."""

        return "%s:%s" % (cls.revid_prefix, git_rev_id)

    @classmethod

    def revision_id_bzr_to_foreign(cls, bzr_rev_id):

        """Convert a Bazaar revision id to a git revision id handle."""

        if not bzr_rev_id.startswith("%s:" % cls.revid_prefix):

            raise errors.InvalidRevisionId(bzr_rev_id, cls)

        return bzr_rev_id[len(cls.revid_prefix)+1:], cls()

    def generate_file_id(self, path):

        # Git paths are just bytestrings

        # We must just hope they are valid UTF-8..

        if path == "":

            return ROOT_ID

        return escape_file_id(path)

    def parse_file_id(self, file_id):

        if file_id == ROOT_ID:

            return ""

        return unescape_file_id(file_id)

    def import_unusual_file_modes(self, rev, unusual_file_modes):

        if unusual_file_modes:

            ret = [(name, unusual_file_modes[name]) for name in sorted(unusual_file_modes.keys())]

            rev.properties['file-modes'] = bencode.bencode(ret)

    def export_unusual_file_modes(self, rev):

        try:

            return dict([(self.generate_file_id(path), mode) for (path, mode) in bencode.bdecode(rev.properties['file-modes'])])

        except KeyError:

            return {}

    def import_commit(self, commit):

        """Convert a git commit to a bzr revision.

        :return: a `bzrlib.revision.Revision` object.

        """

        if commit is None:

            raise AssertionError("Commit object can't be None")

        rev = ForeignRevision(commit.id, self, self.revision_id_foreign_to_bzr(commit.id))

        rev.parent_ids = tuple([self.revision_id_foreign_to_bzr(p) for p in commit.parents])

        rev.message = commit.message.decode("utf-8", "replace")

        rev.committer = str(commit.committer).decode("utf-8", "replace")

        if commit.committer != commit.author:

            rev.properties['author'] = str(commit.author).decode("utf-8", "replace")

        if commit.commit_time != commit.author_time:

            rev.properties['author-timestamp'] = str(commit.author_time)

        if commit.commit_timezone != commit.author_timezone:

            rev.properties['author-timezone'] = "%d" % (commit.author_timezone, )

        rev.timestamp = commit.commit_time

        rev.timezone = commit.commit_timezone

        return rev

class BzrGitMappingv1(BzrGitMapping):

    revid_prefix = 'git-v1'

    experimental = False

    def __str__(self):

        return self.revid_prefix

class BzrGitMappingExperimental(BzrGitMappingv1):

    revid_prefix = 'git-experimental'

    experimental = True

class GitMappingRegistry(VcsMappingRegistry):

    """Registry with available git mappings."""

    def revision_id_bzr_to_foreign(self, bzr_revid):

        if not bzr_revid.startswith("git-"):

            raise errors.InvalidRevisionId(bzr_revid, None)

        (mapping_version, git_sha) = bzr_revid.split(":", 1)

        mapping = self.get(mapping_version)

        return mapping.revision_id_bzr_to_foreign(bzr_revid)

    parse_revision_id = revision_id_bzr_to_foreign

mapping_registry = GitMappingRegistry()

mapping_registry.register_lazy('git-v1', "bzrlib.plugins.git.mapping",

                                   "BzrGitMappingv1")

mapping_registry.register_lazy('git-experimental', "bzrlib.plugins.git.mapping",

                                   "BzrGitMappingExperimental")

class ForeignGit(ForeignVcs):

    """The Git Stupid Content Tracker"""

    def __init__(self):

        super(ForeignGit, self).__init__(mapping_registry)

    @classmethod

    def show_foreign_revid(cls, foreign_revid):

        return { "git commit": foreign_revid }

foreign_git = ForeignGit()

default_mapping = BzrGitMappingv1()

def text_to_blob(texts, entry):

    from dulwich.objects import Blob

    text = texts.get_record_stream([(entry.file_id, entry.revision)], 'unordered', True).next().get_bytes_as('fulltext')

    blob = Blob()

    blob._text = text

    return blob

def symlink_to_blob(entry):

    from dulwich.objects import Blob

    blob = Blob()

    blob._text = entry.symlink_target

    return blob

def mode_is_executable(mode):

    """Check if mode should be considered executable."""

    return bool(mode & 0111)

def mode_kind(mode):

    """Determine the Bazaar inventory kind based on Unix file mode."""

    entry_kind = (mode & 0700000) / 0100000

    if entry_kind == 0:

        return 'directory'

    elif entry_kind == 1:

        file_kind = (mode & 070000) / 010000

        if file_kind == 0:

            return 'file'

        elif file_kind == 2:

            return 'symlink'

        elif file_kind == 6:

            return 'tree-reference'

        else:

            raise AssertionError(

                "Unknown file kind %d, perms=%o." % (file_kind, mode,))

    else:

        raise AssertionError(

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

def entry_mode(entry):

    """Determine the git file mode for an inventory entry."""

    if entry.kind == 'directory':

        return stat.S_IFDIR

    elif entry.kind == 'symlink':

        return stat.S_IFLNK

    elif entry.kind == 'file':

        mode = stat.S_IFREG | 0644

        if entry.executable:

            mode |= 0111

        return mode

    else:

        raise AssertionError

def directory_to_tree(entry, lookup_ie_sha1, unusual_modes):

    from dulwich.objects import Tree

    tree = Tree()

    for name in sorted(entry.children.keys()):

        ie = entry.children[name]

        try:

            mode = unusual_modes[ie.file_id]

        except KeyError:

            mode = entry_mode(ie)

        tree.add(mode, name.encode("utf-8"), lookup_ie_sha1(ie))

    tree.serialize()

    return tree

def extract_unusual_modes(rev):

    try:

        foreign_revid, mapping = mapping_registry.parse_revision_id(rev.revision_id)

    except errors.InvalidRevisionId:

        return {}

    else:

        return mapping.export_unusual_file_modes(rev)

def inventory_to_tree_and_blobs(inventory, texts, mapping, unusual_modes, cur=None):

    """Convert a Bazaar tree to a Git tree.

    :return: Yields tuples with object sha1, object and path

    """

    from dulwich.objects import Tree

    import stat

    stack = []

    if cur is None:

        cur = ""

    tree = Tree()

    # stack contains the set of trees that we haven't 

    # finished constructing

    for path, entry in inventory.iter_entries():

        while stack and not path.startswith(osutils.pathjoin(cur, "")):

            # We've hit a file that's not a child of the previous path

            tree.serialize()

            sha = tree.id

            yield sha, tree, cur.encode("utf-8")

            mode = unusual_modes.get(cur.encode("utf-8"), stat.S_IFDIR)

            t = (mode, urlutils.basename(cur).encode('UTF-8'), sha)

            cur, tree = stack.pop()

            tree.add(*t)

        if entry.kind == "directory":

            stack.append((cur, tree))

            cur = path

            tree = Tree()

        else:

            if entry.kind == "file":

                blob = text_to_blob(texts, entry)

            elif entry.kind == "symlink":

                blob = symlink_to_blob(entry)

            else:

                raise AssertionError("Unknown kind %s" % entry.kind)

            sha = blob.id

            yield sha, blob, path.encode("utf-8")

            name = urlutils.basename(path).encode("utf-8")

            mode = unusual_modes.get(path.encode("utf-8"), entry_mode(entry))

            tree.add(mode, name, sha)

    while len(stack) > 1:

        tree.serialize()

        sha = tree.id

        yield sha, tree, cur.encode("utf-8")

        mode = unusual_modes.get(cur.encode('utf-8'), stat.S_IFDIR)

        t = (mode, urlutils.basename(cur).encode('UTF-8'), sha)

        cur, tree = stack.pop()

        tree.add(*t)

    tree.serialize()

    yield tree.id, tree, cur.encode("utf-8")

def revision_to_commit(rev, tree_sha, parent_lookup):

    """Turn a Bazaar revision in to a Git commit

    :param tree_sha: Tree sha for the commit

    :param parent_lookup: Function for looking up the GIT sha equiv of a bzr revision

    :return dulwich.objects.Commit represent the revision:

    """

    from dulwich.objects import Commit

    commit = Commit()

    commit.tree = tree_sha

    for p in rev.parent_ids:

        git_p = parent_lookup(p)

        if git_p is not None:

            assert len(git_p) == 40, "unexpected length for %r" % git_p

            commit.parents.append(git_p)

    commit.message = rev.message.encode("utf-8")

    commit.committer = fix_person_identifier(rev.committer.encode("utf-8"))

    commit.author = fix_person_identifier(rev.get_apparent_authors()[0].encode("utf-8"))

    commit.commit_time = long(rev.timestamp)

    if 'author-timestamp' in rev.properties:

        commit.author_time = long(rev.properties['author-timestamp'])

    else:

        commit.author_time = commit.commit_time

    commit.commit_timezone = rev.timezone

    if 'author-timezone' in rev.properties:

        commit.author_timezone = int(rev.properties['author-timezone'])

    else:

        commit.author_timezone = commit.commit_timezone 

    return commit