class Standard::Formatter

def determine_run_mode
  if File.split($PROGRAM_NAME).last == "rake"
    :rake
  else
    :cli
  end
end

def file_finished(file, offenses)
  track_stats(offenses)
  if (uncorrected_offenses = offenses.reject(&:corrected?)).any?
    print_header_once
    uncorrected_offenses.each do |o|
      output.printf("  %s:%d:%d: %s\n", path_to(file), o.line, o.real_column, o.message.tr("\n", " "))
    end
  end
end

def finished(_inspected_files)
  print_fix_suggestion
  print_todo_congratulations
end

def fixable_error_message(command)
  sales_pitch = if !options[:autocorrect]
    if @total_correctable_count > 1
      "fix up to #{@total_correctable_count} problems"
    else
      "potentially fix one problem"
    end
  elsif options[:autocorrect] && options[:safe_autocorrect]
    if @total_correctable_count > 1
      "DANGEROUSLY fix #{@total_correctable_count} problems"
    else
      "DANGEROUSLY fix one problem"
    end
  end
  <<~MSG
    standard: Run `#{command}` to #{sales_pitch}.
  MSG
end

def path_to(file)
  Pathname.new(file).relative_path_from(Pathname.new(Dir.pwd))
end

def potential_fix_mode
  return nil unless @total_correctable_count > 0
  if !options[:autocorrect]
    :fix
  elsif options[:autocorrect] && options[:safe_autocorrect]
    :fix_unsafely
  end
end

def print_fix_suggestion
  if (fix_mode = potential_fix_mode)
    run_mode = determine_run_mode
    command = if run_mode == :rake
      "rake standard:#{fix_mode}"
    else
      "standardrb --#{fix_mode.to_s.tr("_", "-")}"
    end
    output.print fixable_error_message(command)
  end
end

def print_header_once
  return if @header_printed_already
  output.print STANDARD_GREETING
  @header_printed_already = true
end

def print_todo_congratulations
  if @total_uncorrected_count == 0 &&
      options[:todo_file] &&
      options[:todo_ignore_files]&.none?
    output.print <<~HEADER
      Congratulations, you've successfully migrated this project to Standard! Delete `#{options[:todo_file]}` in celebration.
    HEADER
  end
end

def print_todo_warning
  todo_file = options[:todo_file]
  return unless todo_file
  todo_ignore_files = options[:todo_ignore_files]
  return unless todo_ignore_files&.any?
  output.print <<~HEADER
    WARNING: this project is being migrated to standard gradually via `#{todo_file}` and is ignoring these files:
  HEADER
  todo_ignore_files.each do |f|
    output.printf("  %s\n", f)
  end
end

def started(_target_files)
  @header_printed_already = false
  @total_correction_count = 0
  @total_correctable_count = 0
  @total_uncorrected_count = 0
  print_todo_warning
end

def track_stats(offenses)
  corrected = offenses.count(&:corrected?)
  @total_correction_count += corrected
  @total_correctable_count += offenses.count(&:correctable?) - corrected
  @total_uncorrected_count += offenses.count - corrected
end