class RuboCop::CLI::Command::AutoGenerateConfig

def add_formatter
  @options[:formatters] << [Formatter::DisabledConfigFormatter, AUTO_GENERATED_FILE]
end

def add_inheritance_from_auto_generated_file(config_file)
  file_string = " #{relative_path_to_todo_from_options_config}"
  config_file ||= ConfigFinder::DOTFILE
  if File.exist?(config_file)
    files = Array(ConfigLoader.load_yaml_configuration(config_file)['inherit_from'])
    return if files.include?(relative_path_to_todo_from_options_config)
    files.unshift(relative_path_to_todo_from_options_config)
    file_string = "\n  - #{files.join("\n  - ")}" if files.size > 1
    rubocop_yml_contents = existing_configuration(config_file)
  end
  write_config_file(config_file, file_string, rubocop_yml_contents)
  puts "Added inheritance from `#{relative_path_to_todo_from_options_config}` " \
       "in `#{ConfigFinder::DOTFILE}`."
end

def execute_runner
  Environment.new(@options, @config_store, @paths).run(:execute_runner)
end

def existing_configuration(config_file)
  File.read(config_file, encoding: Encoding::UTF_8)
      .sub(/^inherit_from: *[^\n]+/, PLACEHOLDER)
      .sub(/^inherit_from: *(\n *- *[^\n]+)+/, PLACEHOLDER)
end

def line_length_cop(config)
  config.for_cop('Layout/LineLength')
end

def line_length_enabled?(config)
  line_length_cop(config)['Enabled']
end

def max_line_length(config)
  line_length_cop(config)['Max']
end

def maybe_run_line_length_cop
  if only_exclude?
    skip_line_length_cop(PHASE_1_SKIPPED_ONLY_EXCLUDE)
  elsif !line_length_enabled?(@config_store.for_pwd)
    skip_line_length_cop(PHASE_1_DISABLED)
  elsif !same_max_line_length?(@config_store.for_pwd, ConfigLoader.default_configuration)
    skip_line_length_cop(PHASE_1_OVERRIDDEN)
  elsif options_has_only_flag?
    skip_line_length_cop(PHASE_1_SKIPPED_ONLY_COPS)
  else
    run_line_length_cop
  end
end

def only_exclude?
  @options[:auto_gen_only_exclude]
end

def options_has_only_flag?
  @options[:only]
end

def relative_path_to_todo_from_options_config
  return AUTO_GENERATED_FILE unless @options[:config]
  base = Pathname.new(Dir.pwd)
  config_dir = Pathname.new(@options[:config]).realpath.dirname
  # Don't have the path start with `/`
  return AUTO_GENERATED_FILE if config_dir == base
  "#{base.relative_path_from(config_dir)}/#{AUTO_GENERATED_FILE}"
end

def reset_config_and_auto_gen_file
  @config_store = ConfigStore.new
  @config_store.options_config = @options[:config] if @options[:config]
  File.open(AUTO_GENERATED_FILE, 'w') {} # create or truncate if exists
  add_inheritance_from_auto_generated_file(@options[:config])
end

def run
  add_formatter
  reset_config_and_auto_gen_file
  line_length_contents = maybe_run_line_length_cop
  run_all_cops(line_length_contents)
end

def run_all_cops(line_length_contents)
  puts Rainbow(PHASE_2).yellow
  result = execute_runner
  # This run was made with the current maximum length allowed, so append
  # the saved setting for LineLength.
  File.open(AUTO_GENERATED_FILE, 'a') { |f| f.write(line_length_contents) }
  result
end

def run_line_length_cop
  puts Rainbow(PHASE_1).yellow
  @options[:only] = ['Layout/LineLength']
  execute_runner
  @options.delete(:only)
  @config_store = ConfigStore.new
  @config_store.options_config = @options[:config] if @options[:config]
  # Save the todo configuration of the LineLength cop.
  File.read(AUTO_GENERATED_FILE).lines.drop_while { |line| line.start_with?('#') }.join
end

def same_max_line_length?(config1, config2)
  max_line_length(config1) == max_line_length(config2)
end

def skip_line_length_cop(reason)
  puts Rainbow("#{PHASE_1} #{reason}").yellow
  ''
end

def write_config_file(file_name, file_string, rubocop_yml_contents)
  lines = /\S/.match?(rubocop_yml_contents) ? rubocop_yml_contents.split("\n", -1) : []
  unless rubocop_yml_contents&.include?(PLACEHOLDER)
    doc_start_index = lines.index { |line| YAML_OPTIONAL_DOC_START.match?(line) } || -1
    lines.insert(doc_start_index + 1, PLACEHOLDER)
  end
  File.write(file_name, lines.join("\n")
                             .sub(/#{PLACEHOLDER}\n*/o, "inherit_from:#{file_string}\n\n")
                             .sub(/\n\n+\Z/, "\n"))
end