# encoding: utf-8

require 'one_apm/support/helper'

# This class encapsulates an error that was noticed by OneApm in a managed app.
class OneApm::NoticedError
  extend OneApm::CollectionHelper
  include OneApm::Coerce

  attr_accessor :path, :timestamp, :params, :message, :exception_class_name
  attr_reader   :exception_id, :is_internal

  OA_STRIPPED_EXCEPTION_REPLACEMENT_MESSAGE = "Message removed by OneApm 'strip_exception_messages' setting"

  def initialize(path, data, exception, timestamp = Time.now)
    @exception_id = exception.object_id
    @path = path
    @params = OneApm::NoticedError.normalize_params(data)

    @exception_class_name = exception.is_a?(Exception) ? exception.class.name : 'Error'

    # It's critical that we not hold onto the exception class constant in this
    # class. These objects get serialized for Resque to a process that might
    # not have the original exception class loaded, so do all processing now
    # while we have the actual exception!
    @is_internal = (exception.class < OneApm::Agent::InternalAgentError)

    if exception.nil?
      @message = '<no message>'
    elsif exception.respond_to?('original_exception')
      @message = (exception.original_exception || exception).to_s
    else # exception is not nil, but does not respond to original_exception
      @message = exception.to_s
    end


    unless @message.is_a?(String)
      # In pre-1.9.3, Exception.new({}).to_s.class != String
      # That is, Exception#to_s may not return a String instance if one wasn't
      # passed in upon creation of the Exception. So, try to generate a useful
      # String representation of the exception message, falling back to failsafe
      @message = String(@message.inspect) rescue '<unknown message type>'
    end

    # clamp long messages to 4k so that we don't send a lot of
    # overhead across the wire
    @message = @message[0..4095] if @message.length > 4096

    # replace error message if enabled
    if OneApm::Manager.config[:'strip_exception_messages.enabled'] &&
       !self.class.passes_message_whitelist(exception.class)
      @message = OA_STRIPPED_EXCEPTION_REPLACEMENT_MESSAGE
    end

    @timestamp = timestamp
  end

  def ==(other)
    if other.respond_to?(:exception_id)
      exception_id == other.exception_id
    else
      false
    end
  end

  def self.passes_message_whitelist(exception_class)
    OneApm::Manager.config.stripped_exceptions_whitelist.any? do |klass|
      exception_class <= klass
    end
  end

  def to_collector_array(encoder=nil)
    [ OneApm::Helper.time_to_millis(timestamp),
      string(path),
      string(message),
      string(exception_class_name),
      params ]
  end
end