require 'net/smtp'

# メールサーバーの設定
smtp_server = '[MAIl_SERVER]'
smtp_port = 587

# 送信元メールアドレスと認証情報
from_address = '[FROM_MAIL_ADDRESS]'
password = '[PASSWORD]'

# 送信先メールアドレス
to_address = '[TO_MAIL_ADDRESS]'

# 件名と本文
subject = 'Test Email'
body = 'This is a test email from Ruby.'

# メールヘッダ
message = <<MESSAGE
From: #{from_address}
To: #{to_address}
Subject: #{subject}
Date: #{Time.now.strftime("%a, %d %b %Y %H:%M:%S %z")}  # "Date" ヘッダーを追加
MIME-Version: 1.0
Content-type: text/html

#{body}
MESSAGE

# SMTPセッションの確立
Net::SMTP.start(smtp_server, smtp_port, 'localhost', from_address, password, :plain) do |smtp|
  # メール送信
  smtp.send_message(message, from_address, to_address)
end

puts 'Email sent successfully!'