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

module Oboe
  extend OboeBase
  include Oboe_metal

  class Reporter
    ##
    # Initialize the Oboe Context, reporter and report the initialization
    #
    def self.start
      return unless Oboe.loaded

      begin
        Oboe_metal::Context.init()

        if ENV.has_key?("OBOE_GEM_TEST")
          Oboe.reporter = Oboe::FileReporter.new("/tmp/trace_output.bson")
        else
          Oboe.reporter = Oboe::UdpReporter.new(Oboe::Config[:reporter_host], Oboe::Config[:reporter_port])
        end

        # Only report __Init from here if we are not instrumenting a framework.
        # Otherwise, frameworks will handle reporting __Init after full initialization
        unless defined?(::Rails) or defined?(::Sinatra) or defined?(::Padrino) or defined?(::Grape)
          Oboe::API.report_init
        end

      rescue Exception => e
        $stderr.puts e.message
        raise
      end
    end

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

    ##
    # clear_all_traces
    #
    # Truncates the trace output file to zero
    #
    def self.clear_all_traces
      File.truncate($trace_file, 0)
    end

    ##
    # get_all_traces
    #
    # Retrieves all traces written to the trace file
    #
    def self.get_all_traces
      io = File.open($trace_file, "r")
      contents = io.readlines(nil)

      return contents if contents.empty?

      s = StringIO.new(contents[0])

      traces = []

      until s.eof?
        if ::BSON.respond_to? :read_bson_document
          traces << BSON.read_bson_document(s)
        else
          traces << BSON::Document.from_bson(s)
        end
      end

      traces
    end
  end

  class Event
    def self.metadataString(evt)
      evt.metadataString()
    end
  end

  class << self
    def sample?(opts = {})
      begin
        return false unless Oboe.always?

        # Assure defaults since SWIG enforces Strings
        layer   = opts[:layer]      ? opts[:layer].strip      : ''
        xtrace  = opts[:xtrace]     ? opts[:xtrace].strip     : ''
        tv_meta = opts['X-TV-Meta'] ? opts['X-TV-Meta'].strip : ''

        rv = Oboe::Context.sampleRequest(layer, xtrace, 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
      rescue StandardError => e
        Oboe.logger.debug "[oboe/error] sample? error: #{e.inspect}"
        false
      end
    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
  end
end

Oboe.loaded = true