import nodemailer from 'nodemailer'

const transporter = nodemailer.createTransport({
  host: process.env.SMTP_HOST,
  port: parseInt(process.env.SMTP_PORT || '465'),
  secure: true, // true for 465, false for other ports
  auth: {
    user: process.env.SMTP_USER,
    pass: process.env.SMTP_PASS,
  },
})

export async function sendInvitationEmail(
  to: string,
  inviterName: string,
  treeName: string,
  role: string,
  password?: string
) {
  const loginUrl = `${process.env.NEXTAUTH_URL}/auth/signin`
  const roleText = role === 'EDITOR' ? '编辑者' : '查看者'
  
  let htmlContent = `
    <div style="font-family: sans-serif; padding: 20px;">
      <h2>家族树协作邀请</h2>
      <p>您好，</p>
      <p><strong>${inviterName}</strong> 邀请您作为 <strong>${roleText}</strong> 加入家族树 <strong>"${treeName}"</strong>。</p>
  `

  if (password) {
    htmlContent += `
      <p>您的初始登录密码为：<br>
      <strong style="font-size: 18px; background: #eee; padding: 5px 10px; border-radius: 4px;">${password}</strong>
      </p>
      <p>请使用您的邮箱 (${to}) 和上述密码登录。</p>
    `
  } else {
    htmlContent += `
      <p>您可以使用现有的账号登录查看。</p>
    `
  }

  htmlContent += `
      <p>
        <a href="${loginUrl}" style="display: inline-block; background: #2563eb; color: white; padding: 10px 20px; text-decoration: none; border-radius: 5px;">
          立即登录
        </a>
      </p>
      <p style="color: #666; font-size: 12px; margin-top: 30px;">此邮件由中华家谱系统自动发送，请勿回复。</p>
    </div>
  `

  await transporter.sendMail({
    from: process.env.SMTP_FROM,
    to,
    subject: `[中华家谱] ${inviterName} 邀请您协作`,
    html: htmlContent,
  })
}