##############################################################################
#
# Copyright (c) 2002,2007 Nexedi SA 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 Products.CMFActivity.ActivityTool import Message, registerActivity
import sys
#from time import time
from SQLBase import SQLBase, sort_message_key

import transaction

from zLOG import LOG, TRACE, WARNING, ERROR, INFO, PANIC

# Stop validating more messages when this limit is reached
MAX_VALIDATED_LIMIT = 1000
# Read up to this number of messages to validate.
READ_MESSAGE_LIMIT = 1000

MAX_MESSAGE_LIST_SIZE = 100

class SQLDict(SQLBase):
  """
    A simple OOBTree based queue. It should be compatible with transactions
    and provide sequentiality. Should not create conflict
    because use of OOBTree.
  """
  sql_table = 'message'

  # Transaction commit methods
  def prepareQueueMessageList(self, activity_tool, message_list):
    registered_message_list = [m for m in message_list if m.is_registered]
    for i in xrange(0, len(registered_message_list), MAX_MESSAGE_LIST_SIZE):
      message_list = registered_message_list[i:i + MAX_MESSAGE_LIST_SIZE]
      path_list = ['/'.join(m.object_path) for m in message_list]
      active_process_uid_list = [m.active_process_uid for m in message_list]
      method_id_list = [m.method_id for m in message_list]
      priority_list = [m.activity_kw.get('priority', 1) for m in message_list]
      date_list = [m.activity_kw.get('at_date') for m in message_list]
      group_method_id_list = [m.getGroupId() for m in message_list]
      tag_list = [m.activity_kw.get('tag', '') for m in message_list]
      serialization_tag_list = [m.activity_kw.get('serialization_tag', '')
                                for m in message_list]
      order_validation_text_list = []
      processing_node_list = []
      for m in message_list:
        m.order_validation_text = x = self.getOrderValidationText(m)
        # BBB: 'order_validation_text' SQL column is now useless.
        #      If we remove it, 'message' & 'message_queue'  can have the same
        #      schema, and much code can be merged into SQLBase.
        order_validation_text_list.append(x)
        processing_node_list.append(0 if x == 'none' else -1)
      dumped_message_list = map(Message.dump, message_list)
      # The uid_list also is store in the ZODB
      uid_list = activity_tool.getPortalObject().portal_ids.generateNewIdList(
        id_generator='uid', id_group='portal_activity',
        id_count=len(message_list))
      activity_tool.SQLDict_writeMessageList(
        uid_list=uid_list,
        path_list=path_list,
        active_process_uid_list=active_process_uid_list,
        method_id_list=method_id_list,
        priority_list=priority_list,
        message_list=dumped_message_list,
        date_list=date_list,
        group_method_id_list=group_method_id_list,
        tag_list=tag_list,
        serialization_tag_list=serialization_tag_list,
        processing_node_list=processing_node_list,
        order_validation_text_list=order_validation_text_list)

  def generateMessageUID(self, m):
    return (tuple(m.object_path), m.method_id, m.activity_kw.get('tag'), m.activity_kw.get('group_id'))

  def isMessageRegistered(self, activity_buffer, activity_tool, m):
    # BBB: deprecated
    return self.generateMessageUID(m) in activity_buffer.getUidSet(self)

  def registerMessage(self, activity_buffer, activity_tool, m):
    message_id = self.generateMessageUID(m)
    uid_set = activity_buffer.getUidSet(self)
    if message_id in uid_set:
      return
    uid_set.add(message_id)
    super(SQLDict, self).registerMessage(activity_buffer, activity_tool, m)

  def unregisterMessage(self, activity_buffer, activity_tool, m):
    m.is_registered = False # This prevents from inserting deleted messages into the queue
    class_name = self.__class__.__name__
    uid_set = activity_buffer.getUidSet(self)
    uid_set.discard(self.generateMessageUID(m))

  def getRegisteredMessageList(self, activity_buffer, activity_tool):
    message_list = activity_buffer.getMessageList(self)
    return [m for m in message_list if m.is_registered]

  def getProcessableMessageLoader(self, activity_tool, processing_node):
    path_and_method_id_dict = {}
    def load(line):
      # getProcessableMessageList already fetch messages with the same
      # group_method_id, so what remains to be filtered on are path and
      # method_id.
      # XXX: What about tag ?
      path = line.path
      method_id = line.method_id
      key = path, method_id
      uid = line.uid
      original_uid = path_and_method_id_dict.get(key)
      if original_uid is None:
        m = Message.load(line.message, uid=uid, line=line)
        merge_parent = m.activity_kw.get('merge_parent')
        try:
          if merge_parent:
            path_list = []
            while merge_parent != path:
              path = path.rsplit('/', 1)[0]
              assert path
              original_uid = path_and_method_id_dict.get((path, method_id))
              if original_uid is not None:
                return None, original_uid, [uid]
              path_list.append(path)
            uid_list = []
            if path_list:
              result = activity_tool.SQLDict_selectParentMessage(
                path=path_list,
                method_id=method_id,
                group_method_id=line.group_method_id,
                processing_node=processing_node)
              if result: # found a parent
                # mark child as duplicate
                uid_list.append(uid)
                # switch to parent
                line = result[0]
                key = line.path, method_id
                uid = line.uid
                m = Message.load(line.message, uid=uid, line=line)
            # return unreserved similar children
            result = activity_tool.SQLDict_selectChildMessageList(
              path=line.path,
              method_id=method_id,
              group_method_id=line.group_method_id)
            reserve_uid_list = [x.uid for x in result]
            uid_list += reserve_uid_list
            if not line.processing_node:
              # reserve found parent
              reserve_uid_list.append(uid)
          else:
            result = activity_tool.SQLDict_selectDuplicatedLineList(
              path=path,
              method_id=method_id,
              group_method_id=line.group_method_id)
            reserve_uid_list = uid_list = [x.uid for x in result]
          if reserve_uid_list:
            activity_tool.SQLDict_reserveDuplicatedLineList(
              processing_node=processing_node, uid=reserve_uid_list)
          else:
            activity_tool.SQLDict_commit() # release locks
        except:
          self._log(WARNING, 'getDuplicateMessageUidList got an exception')
          activity_tool.SQLDict_rollback() # release locks
          raise
        if uid_list:
          self._log(TRACE, 'Reserved duplicate messages: %r' % uid_list)
        path_and_method_id_dict[key] = uid
        return m, uid, uid_list
      # We know that original_uid != uid because caller skips lines we returned
      # earlier.
      return None, original_uid, [uid]
    return load

  def distribute(self, activity_tool, node_count):
    offset = 0
    assignMessage = getattr(activity_tool, 'SQLBase_assignMessage', None)
    if assignMessage is not None:
      now_date = self.getNow(activity_tool)
      validated_count = 0
      while 1:
        result = self._getMessageList(activity_tool, processing_node=-1,
                                      to_date=now_date,
                                      offset=offset, count=READ_MESSAGE_LIMIT)
        if not result:
          return
        transaction.commit()

        validation_text_dict = {'none': 1}
        message_dict = {}
        for line in result:
          message = Message.load(line.message, uid=line.uid, line=line)
          if not hasattr(message, 'order_validation_text'): # BBB
            message.order_validation_text = line.order_validation_text
          self.getExecutableMessageList(activity_tool, message, message_dict,
                                        validation_text_dict, now_date=now_date)

        if message_dict:
          message_unique_dict = {}
          serialization_tag_dict = {}
          distributable_uid_set = set()
          deletable_uid_list = []

          # remove duplicates
          # SQLDict considers object_path, method_id, tag to unify activities,
          # but ignores method arguments. They are outside of semantics.
          for message in message_dict.itervalues():
            message_unique_dict.setdefault(self.generateMessageUID(message),
                                           []).append(message)
          for message_list in message_unique_dict.itervalues():
            if len(message_list) > 1:
              # Sort list of duplicates to keep the message with highest score
              message_list.sort(key=sort_message_key)
              deletable_uid_list += [m.uid for m in message_list[1:]]
            message = message_list[0]
            serialization_tag = message.activity_kw.get('serialization_tag')
            if serialization_tag is None:
              distributable_uid_set.add(message.uid)
            else:
              serialization_tag_dict.setdefault(serialization_tag,
                                                []).append(message)
          # Don't let through if there is the same serialization tag in the
          # message dict. If there is the same serialization tag, only one can
          # be validated and others must wait.
          # But messages with group_method_id are exceptions. serialization_tag
          # does not stop validating together. Because those messages should
          # be processed together at once.
          for message_list in serialization_tag_dict.itervalues():
            # Sort list of messages to validate the message with highest score
            message_list.sort(key=sort_message_key)
            distributable_uid_set.add(message_list[0].uid)
            group_method_id = message_list[0].line.group_method_id
            if group_method_id == '\0':
              continue
            for message in message_list[1:]:
              if group_method_id == message.line.group_method_id:
                distributable_uid_set.add(message.uid)
          if deletable_uid_list:
            activity_tool.SQLBase_delMessage(table=self.sql_table,
                                             uid=deletable_uid_list)
          distributable_count = len(distributable_uid_set)
          if distributable_count:
            assignMessage(table=self.sql_table,
              processing_node=0, uid=tuple(distributable_uid_set))
            validated_count += distributable_count
            if validated_count >= MAX_VALIDATED_LIMIT:
              return
        offset += READ_MESSAGE_LIMIT

registerActivity(SQLDict)