require_relative '../student'
require_relative 'persistence_strategy'

class TXTPersistenceStrategy
  include PersistenceStrategy

  def load(filename)
    if File.exist?(filename)
      File.open(filename, 'r') do |file|
        file.each_line.map do |line|
          line.strip!
          next if line.empty?
          begin
            Student.from_string(line)
          rescue ArgumentError => e
            warn "Ошибка при парсинге строки: #{line}. #{e.message}"
            nil
          end
        end.compact
      end
    else
      []
    end
  end

  def save(filename, students)
    File.open(filename, 'w') do |file|
      students.each do |student|
        file.puts student.to_s
      end
    end
  end
end