# encoding: utf-8

require 'one_apm/transaction/sample_buffer/transaction_sample_buffer'

module OneApm
  class Transaction
    class DeveloperModeSampleBuffer < TransactionSampleBuffer

      CAPACITY = 100

      def capacity
        max_capacity
      end

      # Dev mode is allowed more than the typical upper limit.
      # Sidestep normal cap by overriding max_capacity.
      def max_capacity
        CAPACITY
      end

      def harvest_samples
        NO_SAMPLES
      end

      def enabled?
        Manager.config[:developer_mode]
      end

      # Truncate to the last capacity samples we've received
      def truncate_samples
        @samples = @samples.last(capacity)
      end

      # We don't hold onto previously trapped transactions on harvest
      # We've already got all the traces we want, thank you!
      def store_previous(*)
      end

      # Captures the stack trace for a segment
      # This is expensive and not for production mode
      def visit_segment(segment)
        return unless enabled? && segment

        trace = strip_oneapm_frames(caller)
        trace = trace.first(40) if trace.length > 40
        segment[:backtrace] = trace
      end

      def strip_oneapm_frames(trace)
        while trace.first =~ /lib\/one_apm/
          trace.shift
        end
        trace
      end

    end
  end
end