module Oboe
  class InstallGenerator < ::Rails::Generators::Base
    source_root File.join(File.dirname(__FILE__), 'templates')
    desc "Copies an oboe initializer files to your application."

    def copy_initializer
      # Set defaults
      @tracing_mode = 'through'
      @sampling_rate = '300000'
      @verbose = 'false'

      say ""
      say set_color "Welcome to the Tracelytics Ruby instrumentation setup.", :green, :bold
      say ""
      say "To instrument your Rails application, you have the option to setup sampling strategies here."
      say ""
      say "More information on instrumenting Ruby applications can be found here:"
      say "http://support.tracelytics.com/kb/ruby/instrumenting-ruby-apps"
      while true do
        say ""
        say set_color "Tracing Mode", :green
        say "------------"
        say "When traces should be initiated for incoming requests. Valid options are 'always',"
        say "'through' (when the request is initiated with a tracing header from upstream) and 'never'."
        say "You must set this directive to 'always' in order to initiate tracing."
        say ""
        user_tracing_mode = ask set_color "* Tracing Mode? [through]:", :yellow
        user_tracing_mode.downcase!

        break if user_tracing_mode.blank?
        valid = ['always', 'through', 'never'].include?(user_tracing_mode)
        say set_color "Valid values are 'always', 'through' or 'never'", :red, :bold unless valid
        if valid
          @tracing_mode = user_tracing_mode
          break
        end
      end

      if @tracing_mode == "always"
        while true do
          say ""
          say set_color "Sampling Rate", :green
          say "-------------"
          say "This value reflects the number of requests out of every million that will be traced, and must be an integer between 0 and 1000000. Default is 300000 (30%)."
          say ""
          user_sampling_rate = ask set_color "* Sampling Rate? [300000]:", :yellow
          break if user_sampling_rate.blank?

          valid = user_sampling_rate.to_i.between?(1, 1000000)
          say set_color "Sampling Rate must be a number between 1 and 1000000", :red, :bold unless valid
          if valid
            @sampling_rate = user_sampling_rate.to_i
            break
          end
        end
      end

      say ""
      say "You can change these values in the future by modifying config/initializers/oboe.rb"
      say ""
      say "Thanks! Creating initialization file..."
      say ""

      template "oboe_initializer.rb", "config/initializers/oboe.rb"
    end
  end
end