#
# Author:: Kurt Yoder (ktyopscode@yoderhome.com)
# Copyright:: Copyright (c) 2010 Kurt Yoder
# License:: Apache License, Version 2.0
#
# 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 Ohai
  module Common
    module DMI
      # List of IDs and what they translate to
      # from 'man 8 dmidecode'
      # all-lowercase, all non-alphanumeric converted to '_'
      # 128-255 are 'oem_data_[id]'
      # Everything else is 'unknown'
      ID_TO_DESCRIPTION = {
        0 => "bios",
        1 => "system",
        2 => "base_board",
        3 => "chassis",
        4 => "processor",
        5 => "memory_controller",
        6 => "memory_module",
        7 => "cache",
        8 => "port_connector",
        9 => "system_slots",
        10 => "on_board_devices",
        11 => "oem_strings",
        12 => "system_configuration_options",
        13 => "bios_language",
        14 => "group_associations",
        15 => "system_event_log",
        16 => "physical_memory_array",
        17 => "memory_device",
        18 => "32_bit_memory_error",
        19 => "memory_array_mapped_address",
        20 => "memory_device_mapped_address",
        21 => "built_in_pointing_device",
        22 => "portable_battery",
        23 => "system_reset",
        24 => "hardware_security",
        25 => "system_power_controls",
        26 => "voltage_probe",
        27 => "cooling_device",
        28 => "temperature_probe",
        29 => "electrical_current_probe",
        30 => "out_of_band_remote_access",
        31 => "boot_integrity_services",
        32 => "system_boot",
        33 => "64_bit_memory_error",
        34 => "management_device",
        35 => "management_device_component",
        36 => "management_device_threshold_data",
        37 => "memory_channel",
        38 => "ipmi_device",
        39 => "power_supply",
        40 => "additional_information",
        41 => "onboard_devices_extended_information",
        42 => "management_controller_host_interfaces",
        126 => "disabled_entries",
        127 => "end_of_table_marker",
      }.freeze

      # list of IDs to collect from config or default to a sane list that prunes
      # away some of the less useful IDs
      ID_TO_CAPTURE = [ 0, 1, 2, 3, 4, 6, 11 ].freeze

      # the whitelisted DMI IDs. This is combination of the defaults + any additional
      # IDs defined in the :additional_dmi_ids config
      #
      # @return [Array] the list of DMI IDs to capture
      def whitelisted_ids
        if Ohai.config[:additional_dmi_ids]
          if [ Integer, Array ].include?(Ohai.config[:additional_dmi_ids].class)
            return ID_TO_CAPTURE + Array(Ohai.config[:additional_dmi_ids])
          else
            Ohai::Log.warn("The DMI plugin additional_dmi_ids config must be an array of IDs!")
          end
        end
        ID_TO_CAPTURE
      end

      # the human readable description from a DMI ID
      #
      # @param id [String, Integer] the ID to lookup
      #
      # @return [String]
      def id_lookup(id)
        id = id.to_i
        if (id >= 128) && (id <= 255)
          id = "oem_data_#{id}"
        elsif DMI::ID_TO_DESCRIPTION.key?(id)
          id = DMI::ID_TO_DESCRIPTION[id]
        else
          Ohai::Log.debug("unrecognized header id; falling back to 'unknown'")
          id = "unknown_dmi_id_#{id}"
        end
      rescue
        Ohai::Log.debug("failed to look up id #{id}, returning unchanged")
        id
      end

      # create simplified convenience access keys for each record type
      # for single occurrences of one type, copy to top level all fields and values
      # for multiple occurrences of same type, copy to top level all fields and values that are common to all records
      def convenience_keys(dmi)
        dmi.each do |type, records|
          in_common = Mash.new
          next unless records.is_a?(Mash)
          next unless records.key?("all_records")

          records[:all_records].each do |record|
            record.each do |field, value|
              next if value.is_a?(Mash)
              next if field.to_s == "application_identifier"
              next if field.to_s == "size"
              next if field.to_s == "record_id"

              translated = field.downcase.gsub(/[^a-z0-9]/, "_")
              value      = value.strip
              if in_common.key?(translated)
                in_common[translated] = nil unless in_common[translated] == value
              else
                in_common[translated] = value
              end
            end
          end
          in_common.each do |field, value|
            next if value.nil?

            dmi[type][field] = value.strip
          end
        end
      end

      module_function :id_lookup, :convenience_keys, :whitelisted_ids
    end
  end
end