#
# Fluentd
#
#    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.
#

require 'logger'

module Diagtool
  class ValidUtils
    def initialize(log_level)
      @logger = Logger.new(STDOUT, level: log_level, formatter: proc {|severity, datetime, progname, msg|
        "#{datetime}: [Validutils] [#{severity}] #{msg}\n"
      })
      @def_ulimit = "65535".to_i
      @def_sysctl = Hash.new()
      @def_sysctl = { :net_core_somaxconn => "1024",
        :net_core_netdev_max_backlog => "5000",
        :net_core_rmem_max => "16777216",
        :net_core_wmem_max => "16777216",
        :net_ipv4_tcp_wmem => ["4096", "12582912", "16777216"],
        :net_ipv4_tcp_rmem => ["4096", "12582912", "16777216"],
        :net_ipv4_tcp_max_syn_backlog => "8096",
        :net_ipv4_tcp_slow_start_after_idle => "0",
        :net_ipv4_tcp_tw_reuse => "1",
        :net_ipv4_ip_local_port_range => ["10240", "65535"]}
      @logger.debug("Initialize Validation Utils:")
      @logger.debug("    Default ulimit: #{@def_ulimit}")
      @logger.debug("    Default sysctl: #{@def_sysctl}")
    end
    def valid_ulimit(ulimit_file)
      @logger.info("Loading ulimit file: #{ulimit_file}")
      File.readlines(ulimit_file).each { |line|
        if line.chomp.to_i >= @def_ulimit.to_i
          @logger.info("    ulimit => #{line.chomp.to_i} is correct")
          return true, @def_ulimit.to_i, line.chomp.to_i
        else
          @logger.warn("    ulimit => #{line.chomp.to_i} is incorrect, should be #{@def_ulimit}")
          return false, @def_ulimit.to_i, line.chomp.to_i
        end 
      }
    end
    def valid_sysctl(sysctl_file)
      h = Hash.new()
      v = Hash.new { |i,j| i[j] = Hash.new(&h.default_proc) }
      @logger.info("Loading sysctl file: #{sysctl_file}")
      File.readlines(sysctl_file).each{ |line|
        if line.include?("net")
          line_net = line.chomp.gsub(".","_").split("=")
          key = line_net[0].strip.to_sym
          if line_net[1].strip! =~ /\s/
            value = line_net[1].split(/\s/)
          else
            value= line_net[1]
          end
          h[key] = value
          if @def_sysctl[key] == value
            @logger.info("#{key} => #{value} is correct")
            v[key]['value'] = value
            v[key]['recommend'] = @def_sysctl[key]	
            v[key]['result'] = "correct"
          else
            @logger.warn("#{key} => #{value} is incorrect, should be #{@def_sysctl[key]}")
            v[key]['value'] = value
            v[key]['recommend'] = @def_sysctl[key]
            v[key]['result'] = "incorrect"
          end
        end
      }
      if h == @sysctl
        return true, v
      else
        return false, v
      end
    end
  end
end