# Copyright (c) 2013 AppNeta
# All rights reserved.

require 'base'

module Oboe_metal
  class Context
    class << self
      attr_accessor :layer_op
      
      def log(layer, label, options = {}, with_backtrace = false)
        evt = Oboe::Context.createEvent()
        evt.addInfo("Layer", layer.to_s)
        evt.addInfo("Label", label.to_s)

        options.each_pair do |k, v|
          evt.addInfo(k.to_s, v.to_s)
        end

        evt.addInfo("Backtrace", Oboe::API.backtrace) if with_backtrace

        Oboe.reporter.sendReport(evt) if Oboe.loaded
      end
       
      def tracing_layer_op?(operation)
        if operation.is_a?(Array)
          return operation.include?(@layer_op)
        else
          return @layer_op == operation
        end
      end
    end
  end

  class Event
    def self.metadataString(evt)
      evt.metadataString()
    end
  end
  
  class Reporter
    ##
    # Initialize the Oboe Context, reporter and report the initialization
    #
    def self.start
      begin
        return unless Oboe.loaded

        if Oboe.reporter
          Oboe.logger.warn "[oboe/warn] Attempt to start an already started reporter..."
          return
        end

        Oboe_metal::Context.init()

        Oboe.logger.debug "[oboe/debug] Initializing Heroku based reporter."
        
        # The Oboe Reporter is configured via Heroku config variables.
        Oboe.reporter = Oboe::Reporter.new(nil, nil)

        Oboe::API.report_init
      rescue Exception => e
        $stderr.puts e.message
        raise
      end
    end

    def self.sendReport(evt)
      Oboe.reporter.sendReport(evt) if Oboe.loaded
    end
  end
end

module Oboe 
  extend OboeBase
  include Oboe_metal

  class << self
    def sample?(opts = {})
      # Assure defaults since SWIG enforces Strings
      opts[:layer]      ||= ''
      opts[:xtrace]     ||= ''
      opts['X-TV-Meta'] ||= ''

      rv = Oboe::Context.sampleRequest(opts[:layer], opts[:xtrace], opts['X-TV-Meta'])

      # For older liboboe that returns true/false, just return that.
      return rv if [TrueClass, FalseClass].include?(rv.class) or (rv == 0)

      # liboboe version > 1.3.1 returning a bit masked integer with SampleRate and
      # source embedded
      Oboe.sample_rate = (rv & SAMPLE_RATE_MASK)
      Oboe.sample_source = (rv & SAMPLE_SOURCE_MASK) >> 24

      rv
    end
    
    def set_tracing_mode(mode)
      return unless Oboe.loaded

      value = mode.to_sym

      case value
      when :never
        Oboe::Context.setTracingMode(OBOE_TRACE_NEVER)

      when :always
        Oboe::Context.setTracingMode(OBOE_TRACE_ALWAYS)

      when :through
        Oboe::Context.setTracingMode(OBOE_TRACE_THROUGH)

      else
        Oboe.logger.fatal "[oboe/error] Invalid tracing mode set: #{mode}"
        Oboe::Context.setTracingMode(OBOE_TRACE_THROUGH)
      end
    end

    def set_sample_rate(rate)
      if Oboe.loaded
        # Update liboboe with the new SampleRate value
        Oboe::Context.setDefaultSampleRate(rate.to_i)
      end
    end

    # Disconnect/Reconnect wrappers used for forking webservers
    # such as Unicorn or Passenger
    #
    def disconnect!
      # To avoid an issue with SSL reconnects, delay Reporter initialization
      # until after the fork is completed.  Here, do nothing for now.
    end

    def reconnect!
      Oboe::Reporter.start
    end
  end
end

Oboe.loaded = true