# Copyright (C) 2006 by Szilveszter Farkas (Phanatic) <szilveszter.farkas@gmail.com>
# Some parts of the code are:
# Copyright (C) 2005, 2006 by 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

import errno
import os

import bzrlib
import bzrlib.bzrdir as bzrdir

from bzrlib.branch import Branch

from bzrlib.errors import (AlreadyBranchError, BranchExistsWithoutWorkingTree)

def branch(from_location, to_location, revision=None):
    """ Create a branch from a local/remote location.
    
    :param from_location: the original location of the branch
    
    :param to_location: the directory where the branch should be created
    
    :param revision: if specified, the given revision will be branched
    
    :return: number of revisions branched
    """
    from bzrlib.transport import get_transport

    br_from = Branch.open(from_location)

    br_from.lock_read()

    try:
        basis_dir = None
        if revision is not None:
            revision_id = br_from.get_rev_id(revision)
        else:
            revision_id = None

        to_location = to_location + '/' + os.path.basename(from_location.rstrip("/\\"))
        name = None
        to_transport = get_transport(to_location)

        to_transport.mkdir('.')

        try:
            dir = br_from.bzrdir.sprout(to_transport.base, revision_id, basis_dir)
            branch = dir.open_branch()
        except NoSuchRevision:
            to_transport.delete_tree('.')
            raise

        if name:
            branch.control_files.put_utf8('branch-name', name)
    finally:
        br_from.unlock()
        
    return branch.revno()

def checkout(branch_location, to_location, revision=None, lightweight=False):
    """ Create a new checkout of an existing branch.
    
    :param branch_location: the location of the branch you'd like to checkout
    
    :param to_location: the directory where the checkout should be created
    
    :param revision: the given revision will be checkout'ed (be aware!)
    
    :param lightweight: perform a lightweight checkout (be aware!)
    """
    source = Branch.open(branch_location)
    
    if revision is not None:
        revision_id = source.get_rev_id(revision)
    else:
        revision_id = None

    # if the source and to_location are the same, 
    # and there is no working tree,
    # then reconstitute a branch
    if (bzrlib.osutils.abspath(to_location) ==
        bzrlib.osutils.abspath(branch_location)):
        try:
            source.bzrdir.open_workingtree()
        except NoWorkingTree:
            source.bzrdir.create_workingtree()
            return

    to_location = to_location + '/' + os.path.basename(branch_location.rstrip("/\\"))
    
    os.mkdir(to_location)

    old_format = bzrlib.bzrdir.BzrDirFormat.get_default_format()
    bzrlib.bzrdir.BzrDirFormat.set_default_format(bzrdir.BzrDirMetaFormat1())

    try:
        if lightweight:
            checkout = bzrdir.BzrDirMetaFormat1().initialize(to_location)
            bzrlib.branch.BranchReferenceFormat().initialize(checkout, source)
        else:
            checkout_branch = bzrlib.bzrdir.BzrDir.create_branch_convenience(
                to_location, force_new_tree=False)
            checkout = checkout_branch.bzrdir
            checkout_branch.bind(source)
            if revision_id is not None:
                rh = checkout_branch.revision_history()
                checkout_branch.set_revision_history(rh[:rh.index(revision_id) + 1])

        checkout.create_workingtree(revision_id)
    finally:
        bzrlib.bzrdir.BzrDirFormat.set_default_format(old_format)

def init(location):
    """ Initialize a directory.
    
    :param location: full path to the directory you want to be versioned
    """
    from bzrlib.builtins import get_format_type

    format = get_format_type('default')
 
    if not os.path.exists(location):
        os.mkdir(location)
 
    try:
        existing_bzrdir = bzrdir.BzrDir.open(location)
    except NotBranchError:
        bzrdir.BzrDir.create_branch_convenience(location, format=format)
    else:
        if existing_bzrdir.has_branch():
            if existing_bzrdir.has_workingtree():
                raise AlreadyBranchError(location)
            else:
                raise BranchExistsWithoutWorkingTree(location)
        else:
            existing_bzrdir.create_branch()
            existing_bzrdir.create_workingtree()