##############################################################################
#
# Copyright (c) 2009 Nexedi SA and Contributors. All Rights Reserved.
#                    Jean-Paul Smets-Solanes <jp@nexedi.com>
#                    Yusuke Muraoka <yusuke@nexedi.com>
#
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# consequences resulting from its eventual inadequacies and bugs
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# 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.
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# 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.
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##############################################################################

from Globals import InitializeClass, PersistentMapping
from AccessControl import ClassSecurityInfo

from Products.CMFCore.PortalFolder import ContentFilter
from Products.ERP5Type import Permissions, PropertySheet, Constraint, Interface
from Products.ERP5.Document.Path import Path
from Products.ERP5.Document.BusinessProcess import BackTrack

import zope.interface

class BusinessPath(Path):
  """
    The BusinessPath class embeds all information related to 
    lead times and parties involved at a give phase of a business
    process.

    BusinessPath are also used as helper to build buildable movements.
    Here is the typical code of an alarm:
   
    Approach 1: explanation per explanation
      builder = portal_deliveries.default_order_builder
      for path in builder.getSpecialiseRelatedValueList() # or wharever category
        for explanation in portal_catalog(buildable=1, portal_type='Order'):
          path.build(explanation)

      Pros: easy explanation based approach
      Cons: buildable column added in delivery table
            reexpand of a finished order might generate remaining buildable

    Approach 2: isBuildable is indexed for SimulationMovements
      isBuildable() method is added to SimulationMovement

      Pros: global select is possible
      Cons: reindex of simulation is required
            slow indexing

    Approach 3: isBuildable is invoked during build "after select" process
      builder = portal_deliveries.default_order_builder
      for path in builder.getSpecialiseRelatedValueList() # or wharever category
        builder.build(causality_uid=path.getUid(),) # Select movemenents

      Pros: global select is possible
      Cons: global select retrieves long lists
            slow build

     Method 3 is best
  """
  meta_type = 'ERP5 Business Path'
  portal_type = 'Business Path'
  isPredicate = 1

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

  # Declarative properties
  property_sheets = ( PropertySheet.Base
                    , PropertySheet.XMLObject
                    , PropertySheet.CategoryCore
                    , PropertySheet.DublinCore
                    , PropertySheet.Folder
                    , PropertySheet.Comment
                    , PropertySheet.Arrow
                    , PropertySheet.Chain
                    , PropertySheet.BusinessPath
                    )

  # Declarative interfaces
  zope.interface.implements(Interface.ICategoryAccessProvider,
                            Interface.IArrow)

  # IBusinessPath Interface
  security.declareProtected(Permissions.AccessContentsInformation, 'getSourceBaseCategoryList')
  def getSourceBaseCategoryList(self):
    """
      Returns all categories which are used to define the source
      of this Arrow
    """
    # Naive implementation - we must use category groups instead
    return ('source', 'source_section', 'source_payment', 'source_project', )

  security.declareProtected(Permissions.AccessContentsInformation, 'getDestinationBaseCategoryList')
  def getDestinationBaseCategoryList(self):
    """
      Returns all categories which are used to define the destination
      of this Arrow
    """
    # Naive implementation - we must use category groups instead
    return ('destination', 'destination_section', 'destination_payment', 'destination_project', )

  # ICategoryAccessProvider overriden methods
  def _getCategoryMembershipList(self, category, **kw):
    """
      Overriden in order to take into account dynamic arrow
      categories
    """
    context = kw.get('context')
    result = Path._getCategoryMembershipList(self, category, **kw)
    if context is not None:
      dynamic_category_list = self._getDynamicCategoryList(context)
      dynamic_category_list= self._filterCategoryList(dynamic_category_list, category, **kw)
      # TODO: static categories should have priority over dynamic categories
      result = dynamic_category_list + result
    return result

  def _getAcquiredCategoryMembershipList(self, category, **kw):
    """
      Overriden in order to take into account dynamic arrow
      categories
    """
    context = kw.pop('context', None)
    result = Path._getAcquiredCategoryMembershipList(self, category, **kw)
    if context is not None:
      dynamic_category_list = self._getDynamicCategoryList(context)
      dynamic_category_list= self._filterCategoryList(dynamic_category_list, category, **kw)
      # TODO: static categories should have priority over dynamic categories
      result = dynamic_category_list + result
    return result

  def _filterCategoryList(self, category_list, category, spec=(), filter=None, portal_type=(), base=0, 
                         keep_default=1, checked_permission=None):
    """
      XXX - implementation missing
      TBD - look at CategoryTool._buildFilter for inspiration
    """
    return category_list

  # Dynamic context based categories
  def _getDynamicCategoryList(self, context):
    return self._getDynamicSourceCategoryList(context) \
         + self._getDynamicDestinationCategoryList(context)

  def _getDynamicSourceCategoryList(self, context):
    method_id = self.getSourceMethodId()
    if method_id:
      method = getattr(self, method_id)
      return method(context)
    return []

  def _getDynamicDestinationCategoryList(self, context):
    method_id = self.getDestinationMethodId()
    if method_id:
      method = getattr(self, method_id)
      return method(context)
    return []

  # Core API
  def isBuildable(self, explanation):
    """
    """
    if self.isCompleted(explanation):
      return False # No need to build what was already built
    if self.isFrozen(explanation):
      return False # No need to build what is frozen
    predecessor = self.getPredecessorValue()
    if predecessor is None:
      return True # No predecessor, let's build
    if predecessor.isCompleted(explanation):
      return True
    return False

  def isPartiallyBuildable(self, explanation):
    """
      Not sure if this will exist some day XXX
    """

  def _getRelatedSimulationMovementList(self, explanation):
    """
      
    """
    return self.getCausalityRelatedValueList(portal_type='Simulation Movement',
                                             explanation_uid=explanation.getUid())

  def isCompleted(self, explanation):
    """
      Looks at all simulation related movements
      and checks the simulation_state of the delivery
    """
    acceptable_state_list = self.getCompletedStateList()
    for movement in self._getRelatedSimulationMovementList(explanation):
      if movement.getSimulationState() not in acceptable_state_list:
        return False
    return True

  def isPartiallyCompleted(self, explanation):
    """
      Looks at all simulation related movements
      and checks the simulation_state of the delivery
    """
    acceptable_state_list = self.getCompletedStateList()
    for movement in self._getRelatedSimulationMovementList(explanation):
      if movement.getSimulationState() in acceptable_state_list:
        return True
    return False

  def isFrozen(self, explanation):
    """
      Looks at all simulation related movements
      and checks if frozen
    """
    movement_list = self._getRelatedSimulationMovementList(explanation)
    if len(movement_list) == 0:
      return False # Nothing to be considered as Frozen
    for movement in movement_list:
      if not movement.isFrozen():
        return False
    return True

  def build(self, explanation):
    """
      Build
    """
    builder_list = self.getBuilderList() # Missing method
    for builder in builder_list:
      builder.build(causality_uid=self.getUid()) # This is one way of doing
      builder.build(movement_relative_url_list=
        self._getRelatedSimulationMovementList(explanation)) # Another way

  # Date calculation
  def getExpectedStartDate(self, explanation, predecessor_date=None, *args, **kwargs):
    """
      Returns the expected start date for this
      path based on the explanation.

      predecessor_date -- if provided, computes the date base on the
                          date value provided
    """
    return self._getExpectedDate(explanation,
                                 self._getRootExplanationExpectedStartDate,
                                 self._getPredecessorExpectedStartDate,
                                 self._getSuccessorExpectedStartDate,
                                 predecessor_date=predecessor_date,
                                 *args, **kwargs)

  def _getRootExplanationExpectedStartDate(self, explanation, *args, **kwargs):
    if self.getParentValue().isStartDateReferential():
      return explanation.getStartDate()
    else:
      return self.getExpectedStopDate(explanation, *args, **kwargs)\
             - self.getLeadTime()

  def _getPredecessorExpectedStartDate(self, explanation, predecessor_date=None, *args, **kwargs):
    if predecessor_date is None:
      node = self.getPredecessorValue()
      if node is not None:
        predecessor_date = node.getExpectedCompletionDate(explanation, *args, **kwargs)
    if predecessor_date is not None:
      return predecessor_date + self.getWaitTime()

  def _getSuccessorExpectedStartDate(self, explanation, *args, **kwargs):
    node = self.getSuccessorValue()
    if node is not None:
      return node.getExpectedBeginningDate(explanation, *args, **kwargs)\
             - self.getLeadTime()

  def getExpectedStopDate(self, explanation, predecessor_date=None, *args, **kwargs):
    """
      Returns the expected stop date for this
      path based on the explanation.

      predecessor_date -- if provided, computes the date base on the
                          date value provided
    """
    return self._getExpectedDate(explanation,
                                 self._getRootExplanationExpectedStopDate,
                                 self._getPredecessorExpectedStopDate,
                                 self._getSuccessorExpectedStopDate,
                                 predecessor_date=predecessor_date,
                                 *args, **kwargs)

  def _getRootExplanationExpectedStopDate(self, explanation, *args, **kwargs):
    if self.getParentValue().isStopDateReferential():
      return explanation.getStopDate()
    else:
      return self.getExpectedStartDate(explanation, *args, **kwargs)\
             + self.getLeadTime()

  def _getPredecessorExpectedStopDate(self, explanation, *args, **kwargs):
    node = self.getPredecessorValue()
    if node is not None:
      return node.getExpectedCompletionDate(explanation, *args, **kwargs)\
             + self.getWaitTime() + self.getLeadTime()

  def _getSuccessorExpectedStopDate(self, explanation, *args, **kwargs):
    node = self.getSuccessorValue()
    if node is not None:
      return node.getExpectedBeginningDate(explanation, *args, **kwargs)

  def _getExpectedDate(self, explanation, root_explanation_method,
                       predecessor_method, successor_method,
                       visited=None, *args, **kwargs):
    """
      Returns the expected stop date for this
      path based on the explanation.

      root_explanation_method -- used when the path is root explanation
      predecessor_method --- used to get expected date of side of predecessor
      successor_method --- used to get expected date of side of successor
      visited -- only used to prevent infinite recursion internally
    """
    if visited is None:
      visited = []

    # mark the path as visited
    if self not in visited:
      visited.append(self)

    if self.isDeliverable():
      return root_explanation_method(
        explanation, visited=visited, *args, **kwargs)

    predecessor_expected_date = None
    try:
      predecessor_expected_date = predecessor_method(
        explanation, visited=visited, *args, **kwargs)
    except BackTrack:
      pass

    successor_expected_date = None
    try:
      successor_expected_date = successor_method(
        explanation, visited=visited, *args, **kwargs)
    except BackTrack:
      pass

    if successor_expected_date is not None or \
       predecessor_expected_date is not None:
      # return minimum expected date but it is not None
      if successor_expected_date is None:
        return predecessor_expected_date
      elif predecessor_expected_date is None:
        return successor_expected_date
      else:
        if predecessor_expected_date < successor_expected_date:
          return predecessor_expected_date
        else:
          return successor_expected_date