## Zope shared file, mixin class, provides XML export/import facilities
## Copyright (C) 2000  J. David Ibáñez, Andres Marzal
##                     Universitat Jaume I, Spain
## email: al028823@alumail.uji.es

## 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.

__doc__ = """XML support"""
__version__ = "0.1"

from string import join, replace
from types import StringType

from Globals import HTML
from Shared.DC.xml import pyexpat


## Mixin class, to export/import objects to/from XML
class XMLio:
  xml_attributes = ()
  xml_elements = ()

  ## To XML
  def _xml_get_attributes(self):
    attributes = []
    for x in self.xml_attributes:
      attributes.append('%s="%s"' % (x, str(getattr(self, x))))
    return attributes

  def xml_get_attributes(self):
    return self._xml_get_attributes()

  def _xml_get_elements(self):
    elements = []
    for x in self.xml_elements:
      elements.append('<%s><![CDATA[%s]]></%s>'
                      % (x, str(getattr(self, x)), x))
    return elements

  def xml_get_elements(self):
    return self._xml_get_elements()


  def _toXML(self):
    attributes = self.xml_get_attributes()
    elements = self.xml_get_elements()

    if elements:
      s = ['<%s %s>' % (self.xml_name, join(attributes))]
      s = s + elements
      s.append('</%s>' % self.xml_name)
    else:
      s = ['<%s %s />' % (self.xml_name, join(attributes))]

    return s

  def toXML(self):
    """ """
    return join(self._toXML(), '\n  ')

  ## From XML
  def xml_start(self, attributes):
    pass

  def start(self, tag, attrs):
    attributes = {}
    for i in range(0, len(attrs), 2):
      attributes[attrs[i]] = decode(attrs[i+1])
    if self._xml_stack:
      element = self._xml_stack[-1]
      if type(element) is not StringType:
        method = '_xml_start_%s' % tag
        if hasattr(element, method):
          new_object = getattr(element, method)(attributes)
          self._xml_stack.append(new_object)
          return
        elif tag in element.xml_elements:
          self._xml_stack.append(tag)
          return      
    elif self.xml_name == tag:
      self.xml_start(attributes)
      self._xml_stack.append(self)
      return
    raise 'Syntax Error: unexpected %s start tag' % tag

  def end(self, tag):
    del self._xml_stack[-1]
    return

  def cdata(self, data):
    if self.in_cdata:
      self.xml_data = self.xml_data + data

  def start_cdata(self):
    self.xml_data = ''
    self.in_cdata=1

  def end_cdata(self):
    self.in_cdata=0
    if len(self._xml_stack) >= 2:
      tag = self._xml_stack[-1]
      element = self._xml_stack[-2]
      if type(tag) is StringType and type(element) is not StringType:
        setattr(element, tag, self.xml_data)
        del self.xml_data
        return
    raise 'Syntax Error: unexpacted CDATA section'



  def fromXML(self, file, text=''):
    """ """
    self._xml_stack = []

    p = pyexpat.ParserCreate()
    p.StartElementHandler = self.start
    p.EndElementHandler = self.end
    p.CharacterDataHandler = self.cdata
    p.StartCdataSectionHandler = self.start_cdata
    p.EndCdataSectionHandler = self.end_cdata

    self.in_cdata = 0

    source = text
    if file != None:
      if hasattr(file, 'filename'):
        ## File upload
        if file.filename:
          source = file.read()
      else:
        ## python file
        source = file.read()

    for c in source[:-1]:
      c = encode(c)
      rv = p.Parse(c, 0)
    rv = p.Parse(source[-1], 1)

    del self.in_cdata
    del self._xml_stack


    if not rv:
      raise '%s at line %s, column %s' % (pyexpat.ErrorString(p.ErrorCode),
                                          p.ErrorLineNumber,
                                          p.ErrorColumnNumber)


  XMLForm = HTML(
    """<HTML><HEAD></HEAD><BODY BGCOLOR="#FFFFFF">
    <dtml-var manage_tabs>
    <H2>Export</H2>
     <FORM ACTION="toXML" METHOD="post"><INPUT TYPE="submit" VALUE=" Export ">
     </FORM>
    <H2>Import</H2>
     <FORM ACTION="fromXML" METHOD="post" ENCTYPE="multipart/form-data">
      <TABLE>
       <TR><TD><INPUT TYPE="file" NAME="file" SIZE="25"></TD></TR>
       <TR><TD><TEXTAREA NAME="text" COLS="60" ROWS="16"></TEXTAREA></TD></TR>
       <TR><TD><INPUT TYPE="submit" VALUE=" From XML "></TD></TR>
      </TABLE>
     </FORM>
    </BODY></HTML>""", globals())


schars = {'á': '_aacute_', 'à': '_agrave_',
          'é': '_eacute_', 'è': '_egrave_',
          'í': '_iacute_', 'ì': '_igrave_',
          'ó': '_oacute_', 'ò': '_ograve_',
          'ú': '_uacute_', 'ù': '_ugrave_',
          'Á': '_Aacute_', 'À': '_Agrave_',
          'É': '_Eacute_', 'È': '_Egrave_',
          'Í': '_Iacute_', 'Ì': '_Igrave_',
          'Ó': '_Oacute_', 'Ò': '_Ograve_',
          'Ú': '_Uacute_', 'Ù': '_Ugrave_',
          'ñ': '_ntilde_', 'Ñ': '_Ntilde_',
          '·': '_mdt_'}

def encode(c):
  return schars.get(c, c)

def decode(s):
  for c, e in schars.items():
    s = replace(s, e, c)
  return s