#
#

# Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Google Inc.
#
# 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., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA.


"""Logical units dealing with OS."""

from ganeti import compat
from ganeti import locking
from ganeti import qlang
from ganeti import query
from ganeti.cmdlib.base import QueryBase, NoHooksLU


class OsQuery(QueryBase):
  FIELDS = query.OS_FIELDS

  def ExpandNames(self, lu):
    # Lock all nodes in shared mode
    # Temporary removal of locks, should be reverted later
    # TODO: reintroduce locks when they are lighter-weight
    lu.needed_locks = {}
    #self.share_locks[locking.LEVEL_NODE] = 1
    #self.needed_locks[locking.LEVEL_NODE] = locking.ALL_SET

    # The following variables interact with _QueryBase._GetNames
    if self.names:
      self.wanted = self.names
    else:
      self.wanted = locking.ALL_SET

    self.do_locking = self.use_locking

  def DeclareLocks(self, lu, level):
    pass

  @staticmethod
  def _DiagnoseByOS(rlist):
    """Remaps a per-node return list into an a per-os per-node dictionary

    @param rlist: a map with node names as keys and OS objects as values

    @rtype: dict
    @return: a dictionary with osnames as keys and as value another
        map, with node UUIDs as keys and tuples of (path, status, diagnose,
        variants, parameters, api_versions) as values, eg::

          {"debian-etch": {"node1-uuid": [(/usr/lib/..., True, "", [], []),
                                          (/srv/..., False, "invalid api")],
                           "node2-uuid": [(/srv/..., True, "", [], [])]}
          }

    """
    all_os = {}
    # we build here the list of nodes that didn't fail the RPC (at RPC
    # level), so that nodes with a non-responding node daemon don't
    # make all OSes invalid
    good_node_uuids = [node_uuid for node_uuid in rlist
                       if not rlist[node_uuid].fail_msg]
    for node_uuid, nr in rlist.items():
      if nr.fail_msg or not nr.payload:
        continue
      for (name, path, status, diagnose, variants,
           params, api_versions) in nr.payload:
        if name not in all_os:
          # build a list of nodes for this os containing empty lists
          # for each node in node_list
          all_os[name] = {}
          for nuuid in good_node_uuids:
            all_os[name][nuuid] = []
        # convert params from [name, help] to (name, help)
        params = [tuple(v) for v in params]
        all_os[name][node_uuid].append((path, status, diagnose,
                                        variants, params, api_versions))
    return all_os

  def _GetQueryData(self, lu):
    """Computes the list of nodes and their attributes.

    """
    # Locking is not used
    assert not (compat.any(lu.glm.is_owned(level)
                           for level in locking.LEVELS
                           if level != locking.LEVEL_CLUSTER) or
                self.do_locking or self.use_locking)

    valid_node_uuids = [node.uuid
                        for node in lu.cfg.GetAllNodesInfo().values()
                        if not node.offline and node.vm_capable]
    pol = self._DiagnoseByOS(lu.rpc.call_os_diagnose(valid_node_uuids))
    cluster = lu.cfg.GetClusterInfo()

    data = {}

    for (os_name, os_data) in pol.items():
      info = query.OsInfo(name=os_name, valid=True, node_status=os_data,
                          hidden=(os_name in cluster.hidden_os),
                          blacklisted=(os_name in cluster.blacklisted_os))

      variants = set()
      parameters = set()
      api_versions = set()

      for idx, osl in enumerate(os_data.values()):
        info.valid = bool(info.valid and osl and osl[0][1])
        if not info.valid:
          break

        (node_variants, node_params, node_api) = osl[0][3:6]
        if idx == 0:
          # First entry
          variants.update(node_variants)
          parameters.update(node_params)
          api_versions.update(node_api)
        else:
          # Filter out inconsistent values
          variants.intersection_update(node_variants)
          parameters.intersection_update(node_params)
          api_versions.intersection_update(node_api)

      info.variants = list(variants)
      info.parameters = list(parameters)
      info.api_versions = list(api_versions)

      data[os_name] = info

    # Prepare data in requested order
    return [data[name] for name in self._GetNames(lu, pol.keys(), None)
            if name in data]


class LUOsDiagnose(NoHooksLU):
  """Logical unit for OS diagnose/query.

  """
  REQ_BGL = False

  @staticmethod
  def _BuildFilter(fields, names):
    """Builds a filter for querying OSes.

    """
    name_filter = qlang.MakeSimpleFilter("name", names)

    # Legacy behaviour: Hide hidden, blacklisted or invalid OSes if the
    # respective field is not requested
    status_filter = [[qlang.OP_NOT, [qlang.OP_TRUE, fname]]
                     for fname in ["hidden", "blacklisted"]
                     if fname not in fields]
    if "valid" not in fields:
      status_filter.append([qlang.OP_TRUE, "valid"])

    if status_filter:
      status_filter.insert(0, qlang.OP_AND)
    else:
      status_filter = None

    if name_filter and status_filter:
      return [qlang.OP_AND, name_filter, status_filter]
    elif name_filter:
      return name_filter
    else:
      return status_filter

  def CheckArguments(self):
    self.oq = OsQuery(self._BuildFilter(self.op.output_fields, self.op.names),
                       self.op.output_fields, False)

  def ExpandNames(self):
    self.oq.ExpandNames(self)

  def Exec(self, feedback_fn):
    return self.oq.OldStyleQuery(self)