require 'json'
require 'date'
require_relative 'students_list_base'
require_relative 'student'

class StudentsListJSON < StudentsListBase
  def load_from_file
    if File.exist?(@filename)
      file_content = File.read(@filename)
      begin
        data = JSON.parse(file_content)
        @students = data.map { |student_hash| hash_to_student(student_hash) }
      rescue JSON::ParserError => e
        warn "Ошибка парсинга JSON: #{e.message}"
        @students = []
      end
    else
      @students = []
    end
    self
  end

  def save_to_file
    data = @students.map { |student| student_to_hash(student) }
    File.open(@filename, 'w') do |file|
      file.write(JSON.pretty_generate(data))
    end
    self
  rescue IOError => e
    warn "Ошибка при записи в файл: #{e.message}"
    self
  end

  private

  def student_to_hash(student)
    {
      'id'         => student.id,
      'git'        => student.git,
      'surname'    => student.surname,
      'name'       => student.name,
      'patronymic' => student.patronymic,
      'birth_date' => student.birth_date.to_s,
      'phone'      => student.phone,
      'telegram'   => student.telegram,
      'email'      => student.email
    }
  end

  def hash_to_student(hash)
    Student.new(
      id:         hash['id'],
      git:        hash['git'],
      surname:    hash['surname'],
      name:       hash['name'],
      patronymic: hash['patronymic'],
      birth_date: Date.parse(hash['birth_date']),
      phone:      hash['phone'],
      telegram:   hash['telegram'],
      email:      hash['email']
    )
  end
end