=begin

= datadog.rb

*Copyright*::    (C) 2013 by Novu, LLC
*Author(s)*::    Tamara Temple <tamara.temple@novu.com>
*Since*::        2013-05-01

== Description

Manage the connection and communication from the app to DataDog service.

== Usage

require '.../datadog.rb'

class MyClass

  include DataDog
  api_key = 'Your DD API Key'
  dogger "Hi from MyClass!"

  begin
    # some operations
  rescue Exception => e
    dogger "Woops, an Error", :type => :error, :body => "#{e.class}: #{e}\n#{e.backtrace.join("\n")}"
  end

  # ... other class code

end

== Caveats

This module integrates with methadone, using it's logging features in
addition to sending the log message to data dog.  This isn't
necessarily the most robust intermingling...

=end

require 'dogapi'
require 'methadone'

module NewBackup

  module DataDog

    include Methadone::CLILogging

    DataDogger = Struct.new :api_key, :environment, :client

    module_function

    def api_key
      $dogger ||= DataDogger.new
      $dogger.api_key
    end
    
    def api_key=(api_key)
      $dogger ||= DataDogger.new
      $dogger.api_key=api_key
      debug "#{self.class}##{__method__}@#{File.basename(__FILE__)}:#{__LINE__}: $dogger.api_key: #{$dogger.api_key}"
    end

    def dogger(msg, options={})

      return if msg.nil? || msg.empty?

      if options[:type] == :error
        error msg
      else
        info msg
      end
      debug "#{self.class}##{__method__}@#{File.basename(__FILE__)}:#{__LINE__}: $dogger exists? #{$dogger.inspect}"
      debug "#{self.class}##{__method__}@#{File.basename(__FILE__)}:#{__LINE__}: $dogger.api_key: #{$dogger.api_key}"
      return if $dogger.api_key.nil? || $dogger.api_key.empty?
      
      $dogger.client ||= Dogapi::Client.new($dogger.api_key)
      debug "#{self.class}##{__method__}@#{File.basename(__FILE__)}:#{__LINE__}: $dogger.client: #{$dogger.client.inspect}"

      $dogger.environment ||= (ENV['RAILS_ENV'].nil? || ENV['RAILS_ENV'].empty?) ? 'development' : ENV['RAILS_ENV']

      hostname = `hostname`.chomp

      emit_options = {
        :msg_title => msg,
        :alert_type => (options[:type] == :error) ? 'error' : 'success',
        :tags => [ "host:#{hostname}", "env:#{$dogger.environment}", "new_backup" ],
        :priority => 'normal',
        :host => hostname,
        :source => 'MyApps'}

      body = options[:body] ||= msg

      this_event = Dogapi::Event.new(body, emit_options)
      debug "#{self.class}##{__method__}@#{File.basename(__FILE__)}:#{__LINE__}: emit_options: #{emit_options.to_yaml}\nbody: #{body}\nthis_event: #{this_event.inspect}"
      $dogger.client.emit_event(this_event)

    end

  end

end