~bzr-pqm/bzr/bzr.dev

# Copyright (C) 2007 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

"""Reconfigure a bzrdir into a new tree/branch/repository layout"""

from bzrlib import (

    branch,

    errors,

    )

class Reconfigure(object):

    def __init__(self, bzrdir, new_bound_location=None):

        self.bzrdir = bzrdir

        self.new_bound_location = new_bound_location

        try:

            self.repository = self.bzrdir.find_repository()

        except errors.NoRepositoryPresent:

            self.repository = None

        try:

            branch = self.bzrdir.open_branch()

            if branch.bzrdir.root_transport.base == bzrdir.root_transport.base:

                self.local_branch = branch

                self.referenced_branch = None

            else:

                self.local_branch = None

                self.referenced_branch = branch

        except errors.NotBranchError:

            self.local_branch = None

            self.referenced_branch = None

        try:

            self.tree = bzrdir.open_workingtree()

        except errors.NoWorkingTree:

            self.tree = None

        self._unbind = False

        self._bind = False

        self._destroy_reference = False

        self._create_branch = False

        self._destroy_tree = False

        self._create_tree = False

        self._create_repository = False

    @staticmethod

    def to_branch(bzrdir):

        """Return a Reconfiguration to convert this bzrdir into a branch

        :param bzrdir: The bzrdir to reconfigure

        :raise errors.AlreadyBranch: if bzrdir is already a branch

        :raise errors.ReconfigurationNotSupported: if bzrdir does not contain

            a branch or branch reference

        """

        reconfiguration = Reconfigure(bzrdir)

        reconfiguration._plan_changes(want_tree=False, want_branch=True,

                                      want_bound=False)

        if not reconfiguration.changes_planned():

            raise errors.AlreadyBranch(bzrdir)

        return reconfiguration

    @staticmethod

    def to_tree(bzrdir):

        """Return a Reconfiguration to convert this bzrdir into a tree

        :param bzrdir: The bzrdir to reconfigure

        :raise errors.AlreadyTree: if bzrdir is already a tree

        :raise errors.ReconfigurationNotSupported: if bzrdir does not contain

            a branch or branch reference

        """

        reconfiguration = Reconfigure(bzrdir)

        reconfiguration._plan_changes(want_tree=True, want_branch=True,

                                      want_bound=False)

        if not reconfiguration.changes_planned():

            raise errors.AlreadyTree(bzrdir)

        return reconfiguration

    @staticmethod

    def to_checkout(bzrdir, bound_location=None):

        """Return a Reconfiguration to convert this bzrdir into a checkout

        :param bzrdir: The bzrdir to reconfigure

        :param bound_location: The location the checkout should be bound to.

        :raise errors.AlreadyCheckout: if bzrdir is already a checkout

        :raise errors.ReconfigurationNotSupported: if bzrdir does not contain

            a branch or branch reference

        """

        reconfiguration = Reconfigure(bzrdir, bound_location)

        reconfiguration._plan_changes(want_tree=True, want_branch=True,

                                      want_bound=True)

        if not reconfiguration.changes_planned():

            raise errors.AlreadyCheckout(bzrdir)

        return reconfiguration

    def _plan_changes(self, want_tree, want_branch, want_bound):

        """Determine which changes are needed to assume the configuration"""

        if self.repository is None:

            self._create_repository = True

        if self.local_branch is None:

            if want_branch is True:

                if self.referenced_branch is not None:

                    self._destroy_reference = True

                    self._create_branch = True

                    if want_bound:

                        self._bind = True

                else:

                    raise errors.ReconfigurationNotSupported(self.bzrdir)

        else:

            if want_bound:

                if self.local_branch.get_bound_location() is None:

                    self._bind = True

            else:

                if self.local_branch.get_bound_location() is not None:

                    self._unbind = True

        if not want_tree and self.tree is not None:

            self._destroy_tree = True

        if want_tree and self.tree is None:

            self._create_tree = True

    def changes_planned(self):

        """Return True if changes are planned, False otherwise"""

        return (self._unbind or self._bind or self._destroy_tree

                or self._create_tree or self._destroy_reference

                or self._create_branch or self._create_repository)

    def _check(self):

        """Raise if reconfiguration would destroy local changes"""

        if self._destroy_tree:

            changes = self.tree.changes_from(self.tree.basis_tree())

            if changes.has_changed():

                raise errors.UncommittedChanges(self.tree)

    def _select_bind_location(self):

        """Select a location to bind to.

        Preference is:

        1. user specified location

        2. branch reference location (it's a kind of bind location)

        3. previous bind location (it was a good choice once)

        4. push location (it's writeable, so committable)

        5. parent location (it's pullable, so update-from-able)

        """

        if self.new_bound_location is not None:

            return self.new_bound_location

        if self.local_branch is not None:

            old_bound = self.local_branch.get_old_bound_location()

            if old_bound is not None:

                return old_bound

            push_location = self.local_branch.get_push_location()

            if push_location is not None:

                return push_location

            parent = self.local_branch.get_parent()

            if parent is not None:

                return parent

        elif self.referenced_branch is not None:

            return self.referenced_branch.base

        raise errors.NoBindLocation(self.bzrdir)

    def apply(self, force=False):

        """Apply the reconfiguration

        :param force: If true, the reconfiguration is applied even if it will

            destroy local changes.

        :raise errors.UncommittedChanges: if the local tree is to be destroyed

            but contains uncommitted changes.

        :raise errors.NoBindLocation: if no bind location was specified and

            none could be autodetected.

        """

        if not force:

            self._check()

        if self._create_repository:

            repo = self.bzrdir.create_repository()

        else:

            repo = self.repository

        if self._create_branch:

            repo.fetch(self.referenced_branch.repository,

                       self.referenced_branch.last_revision())

        if self._destroy_reference:

            reference_info = self.referenced_branch.last_revision_info()

            self.bzrdir.destroy_branch()

        if self._create_branch:

            local_branch = self.bzrdir.create_branch()

            local_branch.set_last_revision_info(*reference_info)

        else:

            local_branch = self.local_branch

        if self._destroy_tree:

            self.bzrdir.destroy_workingtree()

        if self._create_tree:

            self.bzrdir.create_workingtree()

        if self._unbind:

            self.local_branch.unbind()

        if self._bind:

            bind_location = self._select_bind_location()

            local_branch.bind(branch.Branch.open(bind_location))