##############################################################################
#
# Copyright (c) 2002 Nexedi SARL and Contributors. All Rights Reserved.
#                    Jean-Paul Smets-Solanes <jp@nexedi.com>
#
# WARNING: This program as such is intended to be used by professional
# programmers who take the whole responsability of assessing all potential
# consequences resulting from its eventual inadequacies and bugs
# End users who are looking for a ready-to-use solution with commercial
# garantees and support are strongly adviced to contract a Free Software
# Service Company
#
# 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.
#
##############################################################################

from DateTime import DateTime
from operator import add
from xmlrpclib import Fault
import re
import socket

from AccessControl import ClassSecurityInfo, getSecurityManager
from Acquisition import aq_base
from Globals import PersistentMapping
from Products.CMFCore.utils import getToolByName
from Products.ERP5Type import Permissions, PropertySheet, Constraint, Interface
from Products.ERP5Type.XMLObject import XMLObject
from Products.ERP5Type.WebDAVSupport import TextContent
from Products.ERP5Type.Message import Message
from Products.ERP5Type.Utils import convertToUpperCase, convertToMixedCase
from Products.ERP5.Document.Url import UrlMixIn

_MARKER = []
VALID_ORDER_KEY_LIST = ('user_login', 'content', 'file_name', 'input')

def makeSortedTuple(kw):
  items = kw.items()
  items.sort()
  return tuple(items)

class ConversionError(Exception):pass

class ConversionCacheMixin:
  """
    This class provides a generic API to store in the ZODB
    various converted versions of a file or of a string.

    Versions are stored in dictionaries; the class stores also
    generation time of every format and its mime-type string.
    Format can be a string or a tuple (e.g. format, resolution).

    TODO:
    * Implement ZODB BLOB
  """
  # time of generation of various formats
  _cached_time = None # Defensive programming - prevent caching to RAM
  # generated files (cache)
  _cached_data = None # Defensive programming - prevent caching to RAM
  # mime types for cached formats XXX to be refactored
  _cached_mime = None # Defensive programming - prevent caching to RAM

  # Declarative security
  security = ClassSecurityInfo()
  security.declareObjectProtected(Permissions.AccessContentsInformation)

  security.declareProtected(Permissions.ModifyPortalContent, 'clearConversionCache')
  def clearConversionCache(self):
    """
    Clear cache (invoked by interaction workflow upon file upload
    needed here to overwrite class attribute with instance attrs
    """
    self._cached_time = PersistentMapping()
    self._cached_data = PersistentMapping()
    self._cached_mime = PersistentMapping()

  security.declareProtected(Permissions.View, 'updateConversionCache')
  def updateConversionCache(self):
    aself = aq_base(self)
    if not hasattr(aself, '_cached_time') or self._cached_time is None:
      self._cached_time = PersistentMapping()
    if not hasattr(aself, '_cached_data') or self._cached_data is None:
      self._cached_data = PersistentMapping()
    if not hasattr(aself, '_cached_mime') or self._cached_mime is None:
      self._cached_mime = PersistentMapping()

  security.declareProtected(Permissions.View, 'hasConversion')
  def hasConversion(self, **format):
    """
      Checks whether we have a version in this format
    """
    self.updateConversionCache()
    return self._cached_data.has_key(makeSortedTuple(format))

  security.declareProtected(Permissions.View, 'getCacheTime')
  def getCacheTime(self, **format):
    """
      Checks when 
if ever was the file produced
    """
    self.updateConversionCache()
    return self._cached_time.get(makeSortedTuple(format), 0)

  security.declareProtected(Permissions.ModifyPortalContent, 'updateConversion')
  def updateConversion(self, **format):
    self.updateConversionCache()
    self._cached_time[makeSortedTuple(format)] = DateTime()

  security.declareProtected(Permissions.ModifyPortalContent, 'setConversion')
  def setConversion(self, data, mime=None, **format):
    """
    Saves a version of the document in a given format; records mime type
    and conversion time (which is right now).
    """
    self.updateConversionCache()
    tformat = makeSortedTuple(format)
    if mime is not None:
      self._cached_mime[tformat] = mime
    if data is not None:
      self._cached_data[tformat] = data
      self.updateConversion(**format)
    self._p_changed = 1

  security.declareProtected(Permissions.View, 'getConversion')
  def getConversion(self, **format):
    """
    Returns version of the document in a given format, if it has it; otherwise
    returns empty string (the caller should check hasConversion before calling
    this function.

    (we could be much cooler here - pass testing and updating methods to this function
    so that it does it all by itself; this'd eliminate the need for setConversion public method)
    XXX-BG: I'm not sure now what I meant by this...
    """
    self.updateConversionCache()
    tformat = makeSortedTuple(format)
    return self._cached_mime.get(tformat, ''), self._cached_data.get(tformat, '')

  security.declareProtected(Permissions.View, 'getConversionCacheInfo')
  def getConversionCacheInfo(self):
    """
    Get cache details as string (for debugging)
    """
    self.updateConversionCache()
    s = 'CACHE INFO:<br/><table><tr><td>format</td><td>size</td><td>time</td><td>is changed</td></tr>'
    for f in self._cached_time.keys():
      t = self._cached_time[f]
      data = self._cached_data.get(f)
      if data:
        if isinstance(data, str):
          ln = len(data)
        else:
          ln = 0
          while data is not None:
            ln += len(data.data)
            data = data.next
      else:
        ln = 'no data!!!'
      s += '<tr><td>%s</td><td>%s</td><td>%s</td><td>%s</td></tr>' % (f, str(ln), str(t), '-')
    s += '</table>'
    return s


class Document(XMLObject, UrlMixIn):
  """
      Document is an abstract class with all methods
      related to document management in ERP5. This includes
      searchable text, explicit relations, implicit relations,
      metadata, versions, languages, etc.

      Documents may either store their content directly or
      cache content which is retrieved from a specified URL.
      The second case if often referred as "External Document".
      Standalone "External Documents" may be created by specifying
      a URL to the contribution tool which is in charge of initiating
      the download process and selecting the appropriate document type.
      Groups of "External Documents" may also be generated from
      so-called "External Source" (refer to ExternalSource class
      for more information).

      External Documents may be downloaded once or at
      regular interval. The later can be useful to update the content
      of an external source. Previous versions may be stored
      in place or kept in a separate file. 

      There are currently two types of Document subclasses:

      * File for binary file based documents. File
        has subclasses such as Image, OOoDocument,
        PDFDocument, etc. to implement specific conversion
        methods.

      * TextDocument for text based documents. TextDocument
        has subclasses such as Wiki to implement specific
        methods. TextDocument itself has a subclass
        (XSLTDocument) which provides XSLT based analysis
        and transformation of XML content based on XSLT
        templates. 

      Document classes which implement conversion should use
      the ConversionCacheMixin class so that converted values are
      stored inside ZODB and do not need to be recalculated.

      XXX IDEA - ISSUE: generic API for conversion.
        converted_document = document.convert(...)

      Instances can be created directly, or via portal_contributions tool
      which manages document ingestion process whereby a file can be uploaded
      by http or sent in by email or dropped in by webdav or in some other
      way as yet unknown. The ingestion process has the following steps:

      (1) portal type detection
      (2) object creation and upload of data
      (3) metadata discovery (optionally with conversion of data to another format)
      (4) other possible actions to finalise the ingestion (ex. by assigning
          a reference)

      This class handles (3) and calls a ZMI script to do (4).

      Metadata can be drawn from various sources:

      input      -   data supplied with http request or set on the object during (2) (e.g.
                     discovered from email text)
      file_name  -    data which might be encoded in file name
      user_login -   information about user who is contributing the file
      content    -   data which might be derived from document content

      If a certain property is defined in more than one source, it is set according to
      preference order returned by a script 
         Document_getPreferredDocumentMetadataDiscoveryOrderList
         (or any type-based version since discovery is type dependent)

      Methods for discovering metadata are:

        getPropertyDictFromInput
        getPropertyDictFromFileName
        getPropertyDictFromUserLogin
        getPropertyDictFromContent

      Methods for processing content are implemented either in 
      Document class or in Base class:

        getSearchableReferenceList (Base)
        getSearchableText (Base)
        index_html (Document)

      Methods for handling relations are implemented either in 
      Document class or in Base class:

        getImplicitSuccessorValueList (Base)
        getImplicitPredecessorValueList (Base)
        getImplicitSimilarValueList (Base)
        getSimilarCloudValueList (Document)

      Implicit relations consist in finding document references inside
      searchable text (ex. INV-23456) and deducting relations from that.
      Two customisable methods required. One to find a list of implicit references
      inside the content (getSearchableReferenceList) and one to convert a given
      document reference into a list of reference strings which could
      be present in other content (asSearchableReferenceList).

      document.getSearchableReferenceList() returns
        [
         {'reference':' INV-12367'},
         {'reference': 'INV-1112', 'version':'012}', 
         {'reference': 'AB-CC-DRK', 'version':'011', 'language': 'en'}
        ]

      The Document class behaviour can be extended / customized through scripts
      (which are type-based so can be adjusted per portal type).

      * Document_getPropertyDictFromUserLogin - finds a user (by user_login or from session)
        and returns properties which should be set on the document

      * Document_getPropertyDictFromContent - analyzes document content and returns
        properties which should be set on the document

      * Base_getImplicitSuccessorValueList - finds appropriate all documents
        referenced in the current content

      * Base_getImplicitPredecessorValueList - finds document predecessors based on
        the document coordinates (can use only complete coordinates, or also partial)

      * Document_getPreferredDocumentMetadataDiscoveryOrderList - returns an order
        in which metadata should be set/overwritten

      * Document_finishIngestion - called by portal_activities after all the ingestion
        is completed (and after document has been converted, so text_content
        is available if the document has it)

      * Document_getNewRevision - calculates revision number which should be set
        on this document. Implementation depends on revision numbering policy which
        can be very different. Interaction workflow should call setNewRevision method.

      Subcontent: documents may include subcontent (files, images, etc.)
      so that publication of rich content can be path independent.

    Consistency checking:
      Default implementation uses DocumentReferenceConstraint to check if the 
      reference/language/version triplet is unique. Additional constraints
      can be added if necessary.
  """

  meta_type = 'ERP5 Document'
  portal_type = 'Document'
  add_permission = Permissions.AddPortalContent
  isPortalContent = 1
  isRADContent = 1
  isDocument = 1
  __dav_collection__=0

  # Declarative security
  security = ClassSecurityInfo()
  security.declareObjectProtected(Permissions.AccessContentsInformation)

  # Declarative properties
  property_sheets = ( PropertySheet.Base
                    , PropertySheet.XMLObject
                    , PropertySheet.CategoryCore
                    , PropertySheet.DublinCore
                    , PropertySheet.Version
                    , PropertySheet.Document
                    , PropertySheet.Url
                    )

  # Declarative interfaces
  __implements__ = ()

  searchable_property_list = ('title', 'description', 'id', 'reference',
                              'version', 'short_title', 'keyword',
                              'subject', 'source_reference', 'source_project_title')

  data = '' # some day this will be in property sheets
  base_format = 'base storage format'

  ### Content processing methods
  security.declareProtected(Permissions.View, 'index_html')
  def index_html(self, REQUEST, RESPONSE, format=None, force=0, **kw):
    """
      We follow here the standard Zope API for files and images
      and extend it to support format conversion. The idea
      is that an image which ID is "something.jpg" should
      ne directly accessible through the URL
      /a/b/something.jpg. The same is true for a file and
      for any document type which primary purpose is to
      be used by a helper application rather than displayed
      as HTML in a web browser. Exceptions to this approach
      include Web Pages which are intended to be primarily rendered
      withing the layout of a Web Site or withing a standard ERP5 page.
      Please refer to the index_html of TextDocument.

      Should return appropriate format (calling convert
      if necessary) and set headers.

      format - the format specied in the form of an extension
      string (ex. jpeg, html, text, txt, etc.)
      force - convert doc even if it has a cached version which seems to be up2date
      **kw can be various things - e.g. resolution

      TODO:
      - implement guards API so that conversion to certain
        formats require certain permission
      - force parameter should be somehow restricted
        to prevent denial of service attack
    """
    pass

  security.declareProtected(Permissions.View, 'convert')
  def convert(self, format, **kw):
    """
      Main content conversion function, returns result which should
      be returned and stored in cache.
      format - the format specied in the form of an extension
      string (ex. jpeg, html, text, txt, etc.)
      **kw can be various things - e.g. resolution

      TODO:
      - implement guards API so that conversion to certain
        formats require certain permission
    """
    pass

  security.declareProtected(Permissions.View, 'asText')
  def asText(self):
    """
      Converts the content of the document to a textual representation.
    """
    return self.convert('text')

  security.declareProtected(Permissions.View, 'getSearchableText')
  def getSearchableText(self, md=None):
    """
      Used by the catalog for basic full text indexing.
      Uses searchable_property_list attribute to put together various properties
      of the document into one searchable text string.

      XXX-JPS - This method is nice. It should probably be moved to Base class
      searchable_property_list could become a standard class attribute.

      TODO (future): Make this property a per portal type property.
    """
    def getPropertyListOrValue(property):
      """
        we try to get a list, else we get value and convert to list
      """
      val = self.getPropertyList(property)
      if val is None:
        val = self.getProperty(property)
        if val is not None and val != '':
          val = [val]
        else:
          val = []
      else:
        val = list(val)
      return val
    searchable_text = reduce(add, map(lambda x: getPropertyListOrValue(x),
                                                self.searchable_property_list))
    searchable_text = ' '.join(searchable_text)
    return searchable_text

  # Compatibility with CMF Catalog
  SearchableText = getSearchableText

  ### Relation getters
  def getSearchableReferenceList(self):
    """
      Public Method
      
      This method returns a list of dictionaries which can
      be used to find objects by reference. It uses for
      that a regular expression defined at system level
      preferences.
    """
    text = self.getSearchableText()
    regexp = self.portal_preferences.getPreferredDocumentReferenceRegularExpression()
    try:
      rx_search = re.compile(regexp)
    except TypeError: # no regexp in preference
      self.log('please set document reference regexp in preferences')
      return []
    res = rx_search.finditer(text)
    res = [(r.group(), r.groupdict()) for r in res]
    return res
    
  security.declareProtected(Permissions.View, 'getImplicitSuccessorValueList')
  def getImplicitSuccessorValueList(self):
    """
      Find objects which we are referencing (if our text_content contains
      references of other documents). The whole implementation is delegated to
      Base_getImplicitSuccessorValueList script.

      The implementation goes in 2 steps:

    - Step 1: extract with a regular expression
      a list of distionaries with various parameters such as 
      reference, portal_type, language, version, user, etc. This
      part is configured through a portal preference.

    - Step 2: read the list of dictionaries
      and build a list of values by calling portal_catalog
      with appropriate parameters (and if possible build 
      a complex query whenever this becomes available in
      portal catalog)
      
      The script is reponsible for calling getSearchableReferenceList
      so that it can use another approach if needed.
      
      NOTE: passing a group_by parameter may be useful at a
      later stage of the implementation.
    """
    # XXX results should be cached as volatile attributes
    refs = [r[1] for r in self.getSearchableReferenceList()]
    res = self.Base_getImplicitSuccessorValueList(refs)
    # get unique latest (most relevant) versions
    res = [r.getObject().getLatestVersionValue() for r in res]
    res_dict = dict.fromkeys(res)
    return res_dict.keys()

  security.declareProtected(Permissions.View, 'getImplicitPredecessorValueList')
  def getImplicitPredecessorValueList(self):
    """
      This function tries to find document which are referencing us - by reference only, or
      by reference/language etc. Implementation is passed to 
        Base_getImplicitPredecessorValueList

      The script should proceed in two steps:

      Step 1: build a list of references out of the context
      (ex. INV-123456, 123456, etc.)

      Step 2: search using the portal_catalog and use
      priorities (ex. INV-123456 before 123456)
      ( if possible build  a complex query whenever 
      this becomes available in portal catalog )

      NOTE: passing a group_by parameter may be useful at a
      later stage of the implementation.
    """
    # XXX results should be cached as volatile attributes
    method = self._getTypeBasedMethod('getImplicitPredecessorValueList', 
        fallback_script_id = 'Base_getImplicitPredecessorValueList')
    lst = method()
    # make it unique first time (before getting lastversionvalue)
    di = dict.fromkeys([r.getObject() for r in lst])
    # then get latest version and make unique again
    di = dict.fromkeys([o.getLatestVersionValue() for o in di.keys()])
    ref = self.getReference()
    return [o for o in di.keys() if o.getReference() != ref] # every object has its own reference in SearchableText

  security.declareProtected(Permissions.View, 'getImplicitSimilarValueList')
  def getImplicitSimilarValueList(self):
    """
      Analyses content of documents to find out by the content which documents
      are similar. Not implemented yet. 

      No cloud needed because transitive process
    """
    return []

  security.declareProtected(Permissions.View, 'getSimilarCloudValueList')
  def getSimilarCloudValueList(self, depth=0):
    """
      Returns all documents which are similar to us, directly or indirectly, and
      in both directions. In other words, it is a transitive closure of similar 
      relation. Every document is returned in the latest version available.
    """
    lista = {}
    depth = int(depth)

    #gettername = 'get%sValueList' % convertToUpperCase(category)
    #relatedgettername = 'get%sRelatedValueList' % convertToUpperCase(category)

    def getRelatedList(ob, level=0):
      level += 1
      #getter = getattr(self, gettername)
      #relatedgetter = getattr(self, relatedgettername)
      #res = getter() + relatedgetter()
      res = ob.getSimilarValueList() + ob.getSimilarRelatedValueList()
      for r in res:
        if lista.get(r) is None:
          lista[r] = True # we use dict keys to ensure uniqueness
          if level != depth:
            getRelatedList(r, level)

    getRelatedList(self)
    lista_latest = {}
    for o in lista.keys():
      lista_latest[o.getLatestVersionValue()] = True # get latest versions avoiding duplicates again
    if lista_latest.has_key(self): 
      lista_latest.pop(self) # remove this document
    if lista_latest.has_key(self.getLatestVersionValue()): 
      lista_latest.pop(self()) # remove this document

    return lista_latest.keys()

  security.declareProtected(Permissions.View, 'hasFile')
  def hasFile(self):
    """
    Checks whether we have an initial file
    """
    _marker = []
    if getattr(self,'data', _marker) is not _marker: # XXX-JPS - use propertysheet accessors
      d = getattr(self, 'data')
      return d is not None and d != ''
    return False

  ### Version and language getters - might be moved one day to a mixin class in base
  security.declareProtected(Permissions.View, 'getLatestVersionValue')
  def getLatestVersionValue(self, language=None):
    """
      Tries to find the latest version with the latest revision
      of self which the current user is allowed to access.

      If language is provided, return the latest document
      in the language.

      If language is not provided, return the latest version
      in original language or in the user language if the version is
      the same.
    """
    if not self.getReference():
      return self
    catalog = getToolByName(self, 'portal_catalog', None)
    kw = dict(reference=self.getReference(), sort_on=(('version','descending'),('revision','descending'),))
    if language is not None: kw['language'] = language
    res = catalog(**kw)

    original_language = self.getOriginalLanguage()
    user_language = self.Localizer.get_selected_language()

    # if language was given return it
    if language is not None:
      return res[0].getObject()
    else:
      first = res[0]
      in_original = None
      for ob in res:
        if ob.getLanguage() == original_language:
          # this is in original language
          in_original = ob
        if ob.getVersion() != first.getVersion():
          # we are out of the latest version - return in_original or first
          if in_original is not None:
            return in_original.getObject()
          else:
            return first.getObject() # this shouldn't happen in real life
        if ob.getLanguage() == user_language:
          # we found it in the user language
          return ob.getObject()
    # this is the only doc in this version
    return self

  security.declareProtected(Permissions.View, 'getVersionValueList')
  def getVersionValueList(self, version=None, language=None):
    """
      Returns a list of documents with same reference, same portal_type
      but different version and given language or any language if not given.
    """
    catalog = getToolByName(self, 'portal_catalog', None)
    kw = dict(portal_type=self.getPortalType(),
                   reference=self.getReference(),
                   group_by=('revision',),
                   order_by=(('revision', 'descending', 'SIGNED'),)
                  )
    if version: kw['version'] = version
    if language: kw['language'] = language
    return catalog(**kw)

  security.declareProtected(Permissions.View, 'isVersionUnique')
  def isVersionUnique(self):
    """
      Returns true if no other document of the same
      portal_type and reference has the same version and language
      
      XXX should delegate to script with proxy roles
      XXX-JPS revision ?
    """
    catalog = getToolByName(self, 'portal_catalog', None)
    # XXX why this does not work???
    #return catalog.countResults(portal_type=self.getPortalType(),
                                #reference=self.getReference(),
                                #version=self.getVersion(),
                                #language=self.getLanguage(),
                                #) <= 1
    return len(catalog(portal_type=self.getPortalType(),
                                reference=self.getReference(),
                                version=self.getVersion(),
                                language=self.getLanguage(),
                                )) <= 1

  security.declareProtected(Permissions.View, 'getLatestRevisionValue')
  def getLatestRevisionValue(self):
    """
      Returns the latest revision of ourselves
    """
    if not self._checkCompleteCoordinates():
      return None
    catalog = getToolByName(self, 'portal_catalog', None)
    res = catalog(
        reference=self.getReference(),
        language=self.getLanguage(),
        version=self.getVersion(),
        sort_on=(('revision','descending'),)
        )
    if len(res) == 0:
      return None
    return res[0].getObject()

  security.declareProtected(Permissions.View, 'getRevisionValueList')
  def getRevisionValueList(self):
    """
      Returns a list revision strings for a given reference, version, language
      XXX should it return revision strings, or docs (as the func name would suggest)?

      XXX-JPS return values - getRevisionList returns revisions 
    """
    # Use portal_catalog
    if not self._checkCompleteCoordinates():
      return []
    res = self.portal_catalog(reference=self.getReference(),
                  language=self.getLanguage(),
                  version=self.getVersion()
                  )
    d = {}
    for r in res:
      d[r.getRevision()] = True
      revs = d.keys()
      revs.sort(reverse=True)
    return revs

  security.declarePrivate('_checkCompleteCoordinates')
  def _checkCompleteCoordinates(self):
    """
      test if the doc has all coordinates

      XXX-JPS - revision ?
    """
    reference = self.getReference()
    version = self.getVersion()
    language = self.getLanguage()
    return (reference and version and language)
  
  security.declareProtected(Permissions.ModifyPortalContent, 'setNewRevision')
  def setNewRevision(self, immediate_reindex=False):
    """
      Set a new revision number automatically
      Delegates to ZMI script because revision numbering policies can be different.
      Should be called by interaction workflow upon appropriate action.

      Sometimes we should reindex immediately, to avoid other doc setting
      the same revision (if revisions are global and there is heavy traffic)
    """
    # Use portal_catalog without security (proxy roles on scripts)
    method = self._getTypeBasedMethod('getNewRevision', 
        fallback_script_id = 'Document_getNewRevision')
    new_rev = method()
    self.setRevision(new_rev)
    if immediate_reindex:
      self.immediateReindexObject()
    else:
      self.reindexObject()
  
  security.declareProtected(Permissions.View, 'getLanguageList')
  def getLanguageList(self, version=None):
    """
      Returns a list of languages which this document is available in
      for the current user.
    """
    if not self.getReference(): return []
    catalog = getToolByName(self, 'portal_catalog', None)
    kw = dict(portal_type=self.getPortalType(),
                           reference=self.getReference(),
                           group_by=('language',))
    if version is not None:
      kw['version'] = version
    return map(lambda o:o.getLanguage(), catalog(**kw))

  security.declareProtected(Permissions.View, 'getOriginalLanguage')
  def getOriginalLanguage(self):
    """
      Returns the original language of this document.

      XXX-JPS not implemented yet ?
    """
    # Approach 1: use portal_catalog and creation dates
    # Approach 2: use workflow analysis (delegate to script if necessary)
    #             workflow analysis is the only way for multiple orginals
    # XXX - cache or set?
    reference = self.getReference()
    if not reference:
      return 
    catalog = getToolByName(self, 'portal_catalog', None)
    res = catalog(reference=self.getReference(), sort_on=(('creation_date','ascending'),))
    # XXX this should be security-unaware - delegate to script with proxy roles
    return res[0].getLanguage() # XXX what happens if it is empty?
    

  ### Property getters
  # Property Getters are document dependent so that we can
  # handle the weird cases in which needed properties change with the type of document
  # and the usual cases in which accessing content changes with the meta type
  security.declareProtected(Permissions.ModifyPortalContent,'getPropertyDictFromUserLogin')
  def getPropertyDictFromUserLogin(self, user_login=None):
    """
      Based on the user_login, find out as many properties as needed.
      returns properties which should be set on the document
    """
    if user_login is None:
      user_login = str(getSecurityManager().getUser())
    method = self._getTypeBasedMethod('getPropertyDictFromUserLogin',
        fallback_script_id='Document_getPropertyDictFromUserLogin')
    return method(user_login)

  security.declareProtected(Permissions.ModifyPortalContent,'getPropertyDictFromContent')
  def getPropertyDictFromContent(self):
    """
      Based on the document content, find out as many properties as needed.
      returns properties which should be set on the document
    """
    # XXX this method should first make sure we have text content
    # or do a conversion
    method = self._getTypeBasedMethod('getPropertyDictFromContent',
        fallback_script_id='Document_getPropertyDictFromContent')
    return method()

  security.declareProtected(Permissions.ModifyPortalContent,'getPropertyDictFromFileName')
  def getPropertyDictFromFileName(self, file_name):
    """
      Based on the file name, find out as many properties as needed.
      returns properties which should be set on the document
    """
    return self.portal_contributions.getPropertyDictFromFileName(file_name)

  security.declareProtected(Permissions.ModifyPortalContent,'getPropertyDictFromInput')
  def getPropertyDictFromInput(self):
    """
      Get properties which were supplied explicitly to the ingestion method
      (discovered or supplied before the document was created).
    """
    if hasattr(self, '_backup_input'):
      return getattr(self, '_backup_input')
    kw = {}
    for id in self.propertyIds():
      # We should not consider file data
      if id not in ('data', 'categories_list', 'uid', 'id', 'text_content', ) \
            and self.hasProperty(id):
        kw[id] = self.getProperty(id)
    self._backup_input = kw # We could use volatile and pass kw in activate
                            # if we are garanteed that _backup_input does not
                            # disappear within a given transaction
    return kw


  ### Metadata disovery and ingestion methods
  security.declareProtected(Permissions.ModifyPortalContent, 'discoverMetadata')
  def discoverMetadata(self, file_name, user_login=None):
    """
      This is the main metadata discovery function - controls the process
      of discovering data from various sources. The discovery itself is
      delegated to scripts or uses preference-configurable regexps.

      file_name - this parameter is a file name of the form "AA-BBB-CCC-223-en"

      user_login - this is a login string of a person; can be None if the user is
        currently logged in, then we'll get him from session
    """

    # Get the order
    # Preference is made of a sequence of 'user_login', 'content', 'file_name', 'input'
    self.setSourceReference(file_name)
    method = self._getTypeBasedMethod('getPreferredDocumentMetadataDiscoveryOrderList', 
        fallback_script_id = 'Document_getPreferredDocumentMetadataDiscoveryOrderList')
    order_list = list(method())

    # Start with everything until content
    content_index = order_list.index('content')

    # Start with everything until content - build a dictionnary according to the order
    kw = {}
    first_list = order_list[:content_index]
    first_list.reverse()
    for order_id in first_list:
      if order_id not in VALID_ORDER_KEY_LIST:
        # Prevent security attack or bad preferences
        raise AttributeError, "%s is not in valid order key list" % order_id
      method_id = 'getPropertyDictFrom%s' % convertToUpperCase(order_id)
      method = getattr(self, method_id)
      if order_id == 'file_name':
        result = method(file_name)
      elif order_id == 'user_login':
        result = method(user_login)
      else:
        result = method()
      if result is not None:
        kw.update(result)
      
    # Edit content
    try:
      del(kw['portal_type'])
    except KeyError:
      pass

    self.edit(**kw)

    # Finish in second stage
    self.activate().finishMetadataDiscovery()
    
  security.declareProtected(Permissions.ModifyPortalContent, 'finishMetadataDiscovery')
  def finishMetadataDiscovery(self):
    """
      This is called by portal_activities, to leave time-consuming procedures
      for later. It converts what needs conversion to base, and
      does things that can be done only after it is converted).
    """
    self.convertToBase()
    # Get the order from preferences
    # Preference is made of a sequence of 'user_login', 'content', 'file_name', 'input'
    method = self._getTypeBasedMethod('getPreferredDocumentMetadataDiscoveryOrderList', 
        fallback_script_id = 'Document_getPreferredDocumentMetadataDiscoveryOrderList')
    order_list = list(method())

    # Start with everything until content
    content_index = order_list.index('content')

    # do content and everything that is later
    kw = {}
    for order_id in order_list[content_index:]:
      if order_id not in VALID_ORDER_KEY_LIST:
        # Prevent security attack or bad preferences
        raise AttributeError, "%s is not in valid order key list" % order_id
      method_id = 'getPropertyDictFrom%s' % convertToUpperCase(order_id)
      method = getattr(self, method_id)
      if order_id == 'file_name':
        result = method(self.getSourceReference())
      # XXX a problem - if user_login was explicitly supplied 
      # we don't have it here (volatile attr would have been lost by now)
      # so we can't have user_login after content
      #elif order_id == 'user_login':
        #result = method(user_login)
      elif order_id == 'user_login':
        raise AttributeError, "user_login can not be done in second stage"
      else:
        result = method()
      if result is not None:
        kw.update(result)
      
    # Edit content
    self.edit(**kw)

    # Erase backup attributes
    delattr(self, '_backup_input')

    # Finish ingestion by calling method
    self.finishIngestion()

  security.declareProtected(Permissions.ModifyPortalContent, 'finishIngestion')
  def finishIngestion(self):
    """
      Finish the ingestion process by calling the appropriate script
    """
    return self._getTypeBasedMethod('finishIngestion',
        fallback_script_id='Document_finishIngestion')

  security.declareProtected(Permissions.View, 'convertToBase')
  def convertToBase(self, REQUEST=None):
    """
      This is run upon upload of the file to make the first
      conversion; calls _convertToBase which be default does
      nothing.
      Records the result in processing_status_workflow
      In OOo documents it converts into ODF format so that we can easily
      convert into other formats, play with metadata and such.
      In PDF doc it converts to plain text, so that we don't have to
      reconvert every time we reindex the object.
    """
    try:
      msg = self._convertToBase()
      if msg is None:
        msg = 'Converted to %s.' % self.base_format
      self.convertFile(comment=msg) # Invoke workflow method
    except NotImplementedError:# we don't do any workflow action if nothing has been done
      msg = '' 
    except ConversionError, e:
      msg = 'Problem: %s' % (str(e) or 'undefined.')
      self.processFile(comment=msg)
    except Fault, e:
      msg = 'Problem: %s' % (repr(e) or 'undefined.')
      self.processFile(comment=msg)
    except socket.error, e:
      msg = 'Problem: %s' % (repr(e) or 'undefined.')
      self.processFile(comment=msg)
    return msg


  def _convertToBase(self):
    """
      API method - some subclasses store data in a certain 'base' format
      (e.g. OOoDocument uses ODF)

      XXX-JPS What is this ? Explain. Name unclear
    """
    raise NotImplementedError

# vim: filetype=python syntax=python shiftwidth=2
