# Copyright (C) 2014-2015 MongoDB, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

module Mongo
  module Operation
    module Write

      # A MongoDB remove user operation.
      #
      # @example Create the remove user operation.
      #   Write::RemoveUser.new(:db_name => 'test', :name => name)
      #
      # @param [ Hash ] spec The specifications for the remove.
      #
      # @option spec :name [ String ] The user name.
      # @option spec :db_name [ String ] The name of the database.
      #
      # @since 2.0.0
      class RemoveUser
        include Executable
        include Specifiable

        # Execute the remove user operation.
        #
        # @example Execute the operation.
        #   operation.execute(context)
        #
        # @param [ Mongo::Server::Context ] context The context for this operation.
        #
        # @return [ Result ] The operation result.
        #
        # @since 2.0.0
        def execute(context)
          if context.features.write_command_enabled?
            execute_write_command(context)
          else
            execute_message(context)
          end
        end

        private

        def execute_write_command(context)
          Result.new(Command::RemoveUser.new(spec).execute(context)).validate!
        end

        def execute_message(context)
          context.with_connection do |connection|
            Result.new(connection.dispatch([ message, gle ].compact)).validate!
          end
        end

        def message
          Protocol::Delete.new(db_name, Auth::User::COLLECTION, { user: user_name })
        end
      end
    end
  end
end