import nodemailer from "nodemailer";
import type { Transporter } from "nodemailer";
import { getGlobalConfigValue } from "#server/service/config";
import log4js from "logger";

const logger = log4js.getLogger("email");

export interface SmtpConfig {
  host: string;
  port: number;
  user: string;
  pass: string;
  from: string;
  secure: boolean;
}

export async function getSmtpConfig(): Promise<SmtpConfig> {
  const [host, port, user, pass, from, secure] = await Promise.all([
    getGlobalConfigValue("smtpHost"),
    getGlobalConfigValue("smtpPort"),
    getGlobalConfigValue("smtpUser"),
    getGlobalConfigValue("smtpPass"),
    getGlobalConfigValue("smtpFrom"),
    getGlobalConfigValue("smtpSecure"),
  ]);
  return { host, port, user, pass, from, secure };
}

export function createTransporter(config: SmtpConfig): Transporter {
  return nodemailer.createTransport({
    host: config.host,
    port: config.port,
    secure: config.secure,
    auth: config.user
      ? { user: config.user, pass: config.pass }
      : undefined,
  });
}

export async function testSmtpConnection(config: SmtpConfig): Promise<{ success: boolean; message: string }> {
  if (!config.host || !config.port) {
    return { success: false, message: "SMTP 服务器地址和端口未配置" };
  }
  try {
    const transporter = createTransporter(config);
    await transporter.verify();
    return { success: true, message: "SMTP 连接测试成功" };
  } catch (err: unknown) {
    const message = err instanceof Error ? err.message : "未知错误";
    logger.error("SMTP connection test failed: %s", message);
    return { success: false, message: `SMTP 连接失败: ${message}` };
  }
}

export interface SendMailOptions {
  to: string | string[];
  subject: string;
  text?: string;
  html?: string;
}

export async function sendMail(options: SendMailOptions): Promise<{ success: boolean; message: string }> {
  const config = await getSmtpConfig();

  if (!config.host || !config.port) {
    return { success: false, message: "SMTP 服务器未配置，请先在系统设置中配置邮件服务" };
  }

  if (!config.from) {
    return { success: false, message: "发件人地址未配置" };
  }

  try {
    const transporter = createTransporter(config);
    const info = await transporter.sendMail({
      from: config.from,
      to: Array.isArray(options.to) ? options.to.join(", ") : options.to,
      subject: options.subject,
      text: options.text,
      html: options.html,
    });
    logger.info("Email sent to %s, messageId: %s", options.to, info.messageId);
    return { success: true, message: "邮件发送成功" };
  } catch (err: unknown) {
    const message = err instanceof Error ? err.message : "未知错误";
    logger.error("Failed to send email to %s: %s", options.to, message);
    return { success: false, message: `邮件发送失败: ${message}` };
  }
}