# encoding: utf-8
require_library %w{ facter }

module FeduxOrgStdlib
  class SupportInformation
    private

    attr_reader :logger

    public

    def initialize(logger: FeduxOrgStdlib::Logging::Logger.new)
      @logger = logger
    end

    # Output support information as string
    #
    # @return [String]
    #   The available information
    def to_s
      result = []

      max_field_length = determine_max_field_length(facter_fields)

      result << format("%#{max_field_length}s | %s", 'Information', 'Value')
      result << format("%s + %s", '-' * max_field_length, '-' * 40)
      result.concat system_information.sort_by { |key, value| key }.map { |key, value| format("%#{max_field_length}s | %s", key, value) }

      result << ""
      result << ""
      result << ""

      max_field_length = determine_max_field_length(rubygems_information.keys)

      result << format("%#{max_field_length}s | %s", 'Information', 'Value')
      result << format("%s + %s", '-' * max_field_length, '-' * 40)
      result.concat rubygems_information.sort_by { |key, value| key }.map { |key, value| format("%#{max_field_length}s | %s", key, value) }

      result << ""
      result << ""
      result << ""

      max_field_length = determine_max_field_length(installed_rubygems.keys)

      result << format("%#{max_field_length}s | %s", 'Name', 'version')
      result << format("%s + %s", '-' * max_field_length, '-' * 40)
      result.concat installed_rubygems.sort_by { |key, value| key }.map { |key, value| format("%#{max_field_length}s | %s", key, value) }

      result.join "\n"
    end

    private

    def rubygems_information
      result = {}
      result[:ruby] = Gem.ruby
      result[:ruby_engine] = Gem.ruby_engine
      result[:ruby_api_version] = Gem.ruby_engine
      result[:rubygems_version] = Gem.rubygems_version

      result
    end

    def installed_rubygems
      result = {}
      Gem::Specification.find_all.each_with_object(result) { |e, a| a[e.name] = e.version }

      result
    end

    def system_information
      Timeout::timeout(10) do
        Facter.to_hash.keep_if { |key,_| facter_fields.include?(key.to_s) }
      end
    rescue Timeout::Error
      logger.warn 'Getting environment information took to long. Please make sure the name resolver is available. This might cause the latency.'
      {}
    end

    def determine_max_field_length(list)
      list.inject(0) { |memo, f| memo = f.size if f.size > memo ; memo}
    end

    def facter_fields
      %w[
            architecture 
            filesystems 
            hardwareisa 
            hardwaremodel 
            is_virtual 
            kernel 
            kernelmajversion 
            kernelrelease 
            kernelversion 
            memoryfree 
            memoryfree_mb 
            memorysize 
            memorysize_mb 
            memorytotal 
            operatingsystem 
            operatingsystemrelease 
            osfamily 
            path 
            physicalprocessorcount 
            processor0 
            processor1 
            processorcount 
            ps 
            rubysitedir 
            rubyversion 
            selinux 
            swapfree 
            swapfree_mb 
            swapsize 
            swapsize_mb 
            timezone 
            uptime 
            uptime_days 
            uptime_hours 
            uptime_seconds 
            virtual 
      ]
    end

  end
end