/brz/remove-bazaar

#! /usr/bin/env python

# -*- coding: UTF-8 -*-

# 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

"""XML externalization support."""

# "XML is like violence: if it doesn't solve your problem, you aren't

# using enough of it." -- various

# importing this module is fairly slow because it has to load several

# ElementTree bits

try:

    from util.cElementTree import ElementTree, SubElement, Element

except ImportError:

    from util.elementtree.ElementTree import ElementTree, SubElement, Element

from bzrlib.inventory import ROOT_ID, Inventory, InventoryEntry

class Serializer(object):

    """Abstract object serialize/deserialize"""

    def write_inventory(self, inv, f):

        """Write inventory to a file"""

        elt = self._pack_inventory(inv)

        self._write_element(elt, f)

    def read_inventory(self, f):

        return self._unpack_inventory(self._read_element(f))

    def _write_element(self, elt, f):

        ElementTree(elt).write(f, 'utf-8')

        f.write('\n')

    def _read_element(self, f):

        return ElementTree().parse(f)

class _Serializer_v4(Serializer):

    """Version 0.0.4 serializer"""

    __slots__ = []

    def _pack_inventory(self, inv):

        """Convert to XML Element"""

        e = Element('inventory')

        e.text = '\n'

        if inv.root.file_id not in (None, ROOT_ID):

            e.set('file_id', inv.root.file_id)

        for path, ie in inv.iter_entries():

            e.append(self._pack_entry(ie))

        return e

    def _pack_entry(self, ie):

        """Convert InventoryEntry to XML element"""

        e = Element('entry')

        e.set('name', ie.name)

        e.set('file_id', ie.file_id)

        e.set('kind', ie.kind)

        if ie.text_size != None:

            e.set('text_size', '%d' % ie.text_size)

        for f in ['text_id', 'text_sha1']:

            v = getattr(ie, f)

            if v != None:

                e.set(f, v)

        # to be conservative, we don't externalize the root pointers

        # for now, leaving them as null in the xml form.  in a future

        # version it will be implied by nested elements.

        if ie.parent_id != ROOT_ID:

            assert isinstance(ie.parent_id, basestring)

            e.set('parent_id', ie.parent_id)

        e.tail = '\n'

        return e

    def _unpack_inventory(self, elt):

        """Construct from XML Element

        """

        assert elt.tag == 'inventory'

        root_id = elt.get('file_id') or ROOT_ID

        inv = Inventory(root_id)

        for e in elt:

            ie = self._unpack_entry(e)

            if ie.parent_id == ROOT_ID:

                ie.parent_id = root_id

            inv.add(ie)

        return inv

    def _unpack_entry(self, elt):

        assert elt.tag == 'entry'

        ## original format inventories don't have a parent_id for

        ## nodes in the root directory, but it's cleaner to use one

        ## internally.

        parent_id = elt.get('parent_id')

        if parent_id == None:

            parent_id = ROOT_ID

        ie = InventoryEntry(elt.get('file_id'),

                              elt.get('name'),

                              elt.get('kind'),

                              parent_id)

        ie.text_id = elt.get('text_id')

        ie.text_sha1 = elt.get('text_sha1')

        ## mutter("read inventoryentry: %r" % (elt.attrib))

        v = elt.get('text_size')

        ie.text_size = v and int(v)

        return ie

"""singleton instance"""

serializer_v4 = _Serializer_v4()

def pack_xml(o, f):

    """Write object o to file f as XML.

    o must provide a to_element method.

    """

    ElementTree(o.to_element()).write(f, 'utf-8')

    f.write('\n')

def unpack_xml(cls, f):

    return cls.from_element(ElementTree().parse(f))