class RuboCop::Formatter::JUnitFormatter

def add_failure_to(testcase, offenses, cop_name)
  # One failure per offense. Zero failures is a passing test case,
  # for most surefire/nUnit parsers.
  offenses.each do |offense|
    REXML::Element.new('failure', testcase).tap do |failure|
      failure.attributes['type'] = cop_name
      failure.attributes['message'] = offense.message
      failure.add_text(offense.location.to_s)
    end
  end
end

def classname_attribute_value(file)
  file.gsub(/\.rb\Z/, '').gsub("#{Dir.pwd}/", '').tr('/', '.')
end

def file_finished(file, offenses)
  # TODO: Returns all cops with the same behavior as
  # the original rubocop-junit-formatter.
  # https://github.com/mikian/rubocop-junit-formatter/blob/v0.1.4/lib/rubocop/formatter/junit_formatter.rb#L9
  #
  # In the future, it would be preferable to return only enabled cops.
  Cop::Registry.all.each do |cop|
    target_offenses = offenses_for_cop(offenses, cop)
    next unless relevant_for_output?(options, target_offenses)
    REXML::Element.new('testcase', @testsuite).tap do |testcase|
      testcase.attributes['classname'] = classname_attribute_value(file)
      testcase.attributes['name'] = cop.cop_name
      add_failure_to(testcase, target_offenses, cop.cop_name)
    end
  end
end

def finished(_inspected_files)
  @document.write(output, 2)
end

def initialize(output, options = {})
  super
  @document = REXML::Document.new.tap do |document|
    document << REXML::XMLDecl.new
  end
  testsuites = REXML::Element.new('testsuites', @document)
  testsuite = REXML::Element.new('testsuite', testsuites)
  @testsuite = testsuite.tap do |element|
    element.add_attributes('name' => 'rubocop')
  end
end

def offenses_for_cop(all_offenses, cop)
  all_offenses.select do |offense|
    offense.cop_name == cop.cop_name
  end
end

def relevant_for_output?(options, target_offenses)
  !options[:display_only_failed] || target_offenses.any?
end