const nodemailer = require('nodemailer');

// 邮件配置 - 使用环境变量或默认配置
const emailConfig = {
  service: process.env.EMAIL_SERVICE || 'qq',
  auth: {
    user: process.env.EMAIL_USER || 'your-email@qq.com',
    pass: process.env.EMAIL_PASS || 'your-app-password'
  }
};

// 接收邮箱配置
const receiverEmail = process.env.ADMIN_EMAIL || 'admin@yourcompany.com';

// 检查邮件配置是否有效
const isEmailConfigured = emailConfig.auth.user !== 'your-email@qq.com' && 
                         emailConfig.auth.pass !== 'your-app-password' &&
                         receiverEmail !== 'admin@yourcompany.com';

// 创建邮件传输器（仅在配置有效时）
const transporter = isEmailConfigured ? nodemailer.createTransport(emailConfig) : null;

/**
 * 发送联系我们留言通知邮件
 * @param {Object} contactData 联系信息
 * @returns {Promise<boolean>} 发送结果
 */
async function sendContactNotification(contactData) {
  try {
    // 检查邮件配置是否有效
    if (!isEmailConfigured || !transporter) {
      console.log('邮件服务未配置，跳过发送通知邮件');
      return false;
    }

    const { name, email, phone, company, subject, message, createdAt } = contactData;
    
    const mailOptions = {
      from: emailConfig.auth.user,
      to: receiverEmail,
      subject: `【网站留言】${subject}`,
      html: `
        <div style="font-family: Arial, sans-serif; max-width: 600px; margin: 0 auto;">
          <h2 style="color: #333; border-bottom: 2px solid #4CAF50; padding-bottom: 10px;">
            新的联系我们留言
          </h2>
          
          <div style="background-color: #f9f9f9; padding: 20px; border-radius: 5px; margin: 20px 0;">
            <h3 style="color: #555; margin-top: 0;">联系人信息</h3>
            <p><strong>姓名：</strong> ${name}</p>
            <p><strong>邮箱：</strong> <a href="mailto:${email}">${email}</a></p>
            ${phone ? `<p><strong>电话：</strong> ${phone}</p>` : ''}
            ${company ? `<p><strong>公司：</strong> ${company}</p>` : ''}
            <p><strong>留言时间：</strong> ${new Date(createdAt).toLocaleString('zh-CN')}</p>
          </div>
          
          <div style="background-color: #fff; padding: 20px; border: 1px solid #ddd; border-radius: 5px;">
            <h3 style="color: #555; margin-top: 0;">留言主题</h3>
            <p style="font-size: 16px; font-weight: bold; color: #333;">${subject}</p>
            
            <h3 style="color: #555;">留言内容</h3>
            <div style="background-color: #f5f5f5; padding: 15px; border-radius: 3px; line-height: 1.6;">
              ${message.replace(/\n/g, '<br>')}
            </div>
          </div>
          
          <div style="margin-top: 20px; padding: 15px; background-color: #e8f5e8; border-radius: 5px;">
            <p style="margin: 0; color: #666; font-size: 14px;">
              <strong>提示：</strong>请及时回复客户留言，可直接回复到客户邮箱：<a href="mailto:${email}">${email}</a>
            </p>
          </div>
        </div>
      `
    };

    const result = await transporter.sendMail(mailOptions);
    console.log('邮件发送成功:', result.messageId);
    return true;
  } catch (error) {
    console.error('邮件发送失败:', error);
    return false;
  }
}

/**
 * 发送自动回复邮件给客户
 * @param {Object} contactData 联系信息
 * @returns {Promise<boolean>} 发送结果
 */
async function sendAutoReply(contactData) {
  try {
    // 检查邮件配置是否有效
    if (!isEmailConfigured || !transporter) {
      console.log('邮件服务未配置，跳过发送自动回复邮件');
      return false;
    }

    const { name, email, subject } = contactData;
    
    const mailOptions = {
      from: emailConfig.auth.user,
      to: email,
      subject: `感谢您的留言 - ${subject}`,
      html: `
        <div style="font-family: Arial, sans-serif; max-width: 600px; margin: 0 auto;">
          <h2 style="color: #4CAF50;">感谢您的留言！</h2>
          
          <p>尊敬的 ${name}，</p>
          
          <p>感谢您通过我们的网站联系我们。我们已经收到您的留言，我们的工作人员会在24小时内回复您。</p>
          
          <div style="background-color: #f9f9f9; padding: 15px; border-radius: 5px; margin: 20px 0;">
            <p><strong>您的留言主题：</strong>${subject}</p>
            <p><strong>提交时间：</strong>${new Date().toLocaleString('zh-CN')}</p>
          </div>
          
          <p>如有紧急事务，请直接拨打我们的客服电话：<strong>400-xxx-xxxx</strong></p>
          
          <hr style="border: none; border-top: 1px solid #eee; margin: 30px 0;">
          
          <p style="color: #666; font-size: 14px;">
            此邮件为系统自动发送，请勿直接回复。<br>
            如需联系我们，请访问：<a href="https://yourwebsite.com">https://yourwebsite.com</a>
          </p>
        </div>
      `
    };

    const result = await transporter.sendMail(mailOptions);
    console.log('自动回复邮件发送成功:', result.messageId);
    return true;
  } catch (error) {
    console.error('自动回复邮件发送失败:', error);
    return false;
  }
}

module.exports = {
  sendContactNotification,
  sendAutoReply
};