class RuboCop::Formatter::DisabledConfigFormatter

def command
  command = 'rubocop --auto-gen-config'
  if @exclude_limit_option
    command +=
      format(' --exclude-limit %<limit>d',
             limit: Integer(@exclude_limit_option))
  end
  command += ' --no-offense-counts' if @options[:no_offense_counts]
  if @options[:no_auto_gen_timestamp]
    command += ' --no-auto-gen-timestamp'
  end
  command
end

def cop_config_params(default_cfg, cfg)
  default_cfg.keys -
    %w[Description StyleGuide Reference Enabled Exclude Safe
       SafeAutoCorrect VersionAdded VersionChanged VersionRemoved] -
    cfg.keys
end

def default_config(cop_name)
  RuboCop::ConfigLoader.default_configuration[cop_name]
end

def excludes(offending_files, cop_name, parent)
  # Exclude properties in .rubocop_todo.yml override default ones, as well
  # as any custom excludes in .rubocop.yml, so in order to retain those
  # excludes we must copy them.
  # There can be multiple .rubocop.yml files in subdirectories, but we
  # just look at the current working directory
  config = ConfigStore.new.for(parent)
  cfg = config[cop_name] || {}
  ((cfg['Exclude'] || []) + offending_files).uniq
end

def file_finished(file, offenses)
  offenses.each do |o|
    @cops_with_offenses[o.cop_name] += 1
    @files_with_offenses[o.cop_name] ||= Set.new
    @files_with_offenses[o.cop_name] << file
  end
end

def file_started(_file, _file_info)
  @exclude_limit_option = @options[:exclude_limit]
  @exclude_limit = Integer(@exclude_limit_option ||
    RuboCop::Options::DEFAULT_MAXIMUM_EXCLUSION_ITEMS)
  @show_offense_counts = !@options[:no_offense_counts]
end

def finished(_inspected_files)
  output.puts format(HEADING, command: command, timestamp: timestamp)
  # Syntax isn't a real cop and it can't be disabled.
  @cops_with_offenses.delete('Lint/Syntax')
  output_offenses
  puts "Created #{output.path}."
end

def initialize(output, options = {})
  super
  @cops_with_offenses ||= Hash.new(0)
  @files_with_offenses ||= {}
end

def output_cop(cop_name, offense_count)
  output.puts
  cfg = self.class.config_to_allow_offenses[cop_name] || {}
  set_max(cfg, cop_name)
  # To avoid malformed YAML when potentially reading the config in
  # #excludes, we use an output buffer and append it to the actual output
  # only when it results in valid YAML.
  output_buffer = StringIO.new
  output_cop_comments(output_buffer, cfg, cop_name, offense_count)
  output_cop_config(output_buffer, cfg, cop_name)
  output.puts(output_buffer.string)
end

def output_cop_comments(output_buffer, cfg, cop_name, offense_count)
  if @show_offense_counts
    output_buffer.puts "# Offense count: #{offense_count}"
  end
  cop_class = Cop::Cop.registry.find_by_cop_name(cop_name)
  if cop_class && cop_class.new.support_autocorrect?
    output_buffer.puts '# Cop supports --auto-correct.'
  end
  default_cfg = default_config(cop_name)
  return unless default_cfg
  params = cop_config_params(default_cfg, cfg)
  return if params.empty?
  output_cop_param_comments(output_buffer, params, default_cfg)
end

def output_cop_config(output_buffer, cfg, cop_name)
  # 'Enabled' option will be put into file only if exclude
  # limit is exceeded.
  cfg_without_enabled = cfg.reject { |key| key == 'Enabled' }
  output_buffer.puts "#{cop_name}:"
  cfg_without_enabled.each do |key, value|
    value = value[0] if value.is_a?(Array)
    output_buffer.puts "  #{key}: #{value}"
  end
  output_offending_files(output_buffer, cfg_without_enabled, cop_name)
end

def output_cop_param_comments(output_buffer, params, default_cfg)
  config_params = params.reject { |p| p.start_with?('Supported') }
  output_buffer.puts(
    "# Configuration parameters: #{config_params.join(', ')}."
  )
  params.each do |param|
    value = default_cfg[param]
    next unless value.is_a?(Array)
    next if value.empty?
    output_buffer.puts "# #{param}: #{value.join(', ')}"
  end
end

def output_exclude_list(output_buffer, offending_files, cop_name)
  require 'pathname'
  parent = Pathname.new(Dir.pwd)
  output_buffer.puts '  Exclude:'
  excludes(offending_files, cop_name, parent).each do |exclude_path|
    output_exclude_path(output_buffer, exclude_path, parent)
  end
end

def output_exclude_path(output_buffer, exclude_path, parent)
  # exclude_path is either relative path, an absolute path, or a regexp.
  file_path = Pathname.new(exclude_path)
  relative = file_path.relative_path_from(parent)
  output_buffer.puts "    - '#{relative}'"
rescue ArgumentError
  file = exclude_path
  output_buffer.puts "    - '#{file}'"
rescue TypeError
  regexp = exclude_path
  output_buffer.puts "    - !ruby/regexp /#{regexp.source}/"
end

def output_offending_files(output_buffer, cfg, cop_name)
  return unless cfg.empty?
  offending_files = @files_with_offenses[cop_name].sort
  if offending_files.count > @exclude_limit
    output_buffer.puts '  Enabled: false'
  else
    output_exclude_list(output_buffer, offending_files, cop_name)
  end
end

def output_offenses
  @cops_with_offenses.sort.each do |cop_name, offense_count|
    output_cop(cop_name, offense_count)
  end
end

def set_max(cfg, cop_name)
  return unless cfg[:exclude_limit]
  # In case auto_gen_only_exclude is set, only modify the maximum if the
  # files are not excluded one by one.
  if !@options[:auto_gen_only_exclude] ||
     @files_with_offenses[cop_name].size > @exclude_limit
    cfg.merge!(cfg[:exclude_limit])
  end
  # Remove already used exclude_limit.
  cfg.reject! { |key| key == :exclude_limit }
end

def timestamp
  @options[:no_auto_gen_timestamp] ? '' : "on #{Time.now} "
end