#!/usr/bin/env python3
"""
邮件批量通知工具 - CLI 版
用于在新系统切换时批量给全员发送新的账号口令通知

Usage:
    python3 mail_sender.py users.txt
    python3 mail_sender.py users.txt --smtp smtp.ctvit.com.cn --port 465
    python3 mail_sender.py users.txt --sender zhangguozhong@ctvit.com.cn

TXT 格式：每行 邮箱 密码（空格 / tab / | / , 都支持）
"""

import os
import re
import sys
import time
import argparse
import smtplib
import logging
from datetime import datetime
from email.mime.text import MIMEText
from email.header import Header

# =====================================
# 日志配置
# =====================================
logging.basicConfig(
    level=logging.INFO,
    format="%(asctime)s [%(levelname)s] %(message)s",
    datefmt="%Y-%m-%d %H:%M:%S",
)
logger = logging.getLogger("MailSender")


# =====================================
# 邮件模板
# =====================================
DEFAULT_TEMPLATE = """亲爱的用户：

您好！这是您的账号配置信息：

您的邮件账号：{email}
您的初始口令：{password}

请务必妥善保管您的账号信息，不要泄露给他人。
如有疑问，请联系技术支持部门。

---
此邮件为系统自动发送，请勿直接回复。
"""


# =====================================
# TXT 解析
# =====================================
def parse_users(file_path):
    users = []
    with open(file_path, "r", encoding="utf-8") as f:
        for line in f:
            line = line.strip()
            if not line or line.startswith("#"):
                continue
            parts = re.split(r"[\s\t\|:;]+", line)
            if len(parts) < 2:
                continue
            email = parts[0].strip()
            password = parts[1].strip()
            if not email or "@" not in email:
                logger.warning(f"跳过无效行（非邮箱格式）: {line}")
                continue
            users.append({"email": email, "password": password})
    return users


# =====================================
# SMTP 连接（自动探测端口）
# =====================================
def build_smtp(smtp_server, smtp_port, sender_email, sender_pass):
    smtp_port = int(smtp_port)

    # 465 → SSL
    if smtp_port == 465:
        server = smtplib.SMTP_SSL(smtp_server, smtp_port, timeout=30)
        logger.info(f"📡 连接 {smtp_server}:{smtp_port} (SSL)")
        server.login(sender_email, sender_pass)
        return server

    # 587 → STARTTLS
    if smtp_port == 587:
        server = smtplib.SMTP(smtp_server, smtp_port, timeout=30)
        server.ehlo()
        server.starttls()
        server.ehlo()
        logger.info(f"📡 连接 {smtp_server}:{smtp_port} (STARTTLS)")
        server.login(sender_email, sender_pass)
        return server

    # 25 → 明文
    server = smtplib.SMTP(smtp_server, smtp_port, timeout=30)
    logger.info(f"📡 连接 {smtp_server}:{smtp_port} (明文)")
    server.login(sender_email, sender_pass)
    return server


# =====================================
# 单封发送（含重试）
# =====================================
def send_mail(server, sender_email, receiver_email, subject, content, reply_to=None):
    msg = MIMEText(content, "plain", "utf-8")
    msg["From"] = sender_email
    msg["To"] = receiver_email
    msg["Subject"] = Header(subject or "邮件通知", "utf-8")
    if reply_to:
        msg["Reply-To"] = reply_to
    server.sendmail(sender_email, [receiver_email], msg.as_string())


def send_with_retry(
    server, sender_email, receiver_email,
    subject, content, reply_to=None, max_retries=3
):
    last_error = None
    for attempt in range(1, max_retries + 1):
        try:
            send_mail(server, sender_email, receiver_email, subject, content, reply_to)
            return True, None
        except smtplib.SMTPServerDisconnected:
            last_error = "连接断开"
            if attempt < max_retries:
                wait = 2 ** attempt
                logger.warning(f"  ⚠ 连接断开，{wait}s 后重试 (第{attempt}次)")
                time.sleep(wait)
        except smtplib.SMTPResponseException as e:
            code = e.smtp_code
            if 400 <= code < 500 and attempt < max_retries:
                last_error = f"SMTP {code}"
                wait = 2 ** attempt
                logger.warning(f"  ⚠ SMTP {code}，{wait}s 后重试 (第{attempt}次)")
                time.sleep(wait)
            else:
                return False, f"SMTP {code}: {e}"
        except Exception as e:
            return False, str(e)
    return False, last_error


# =====================================
# 主流程
# =====================================
def main():
    parser = argparse.ArgumentParser(
        description="📧 邮件批量通知工具 (CLI)",
        formatter_class=argparse.RawDescriptionHelpFormatter,
        epilog="""
示例：
  python3 mail_sender.py users.txt
  python3 mail_sender.py users.txt --port 465 --sender xxx@qq.com
  python3 mail_sender.py users.txt --subject "系统账号通知" --delay 2
  python3 mail_sender.py users.txt --template my_template.txt
        """,
    )

    parser.add_argument("file", help="用户列表 TXT 文件路径（每行：邮箱 密码）")
    parser.add_argument("--smtp", default="smtp.ctvit.com.cn", help="SMTP 服务器地址（默认 smtp.ctvit.com.cn）")
    parser.add_argument("--port", type=int, default=25, help="SMTP 端口（默认 25，常见 465/587）")
    parser.add_argument("--sender", default="zhangguozhong@ctvit.com.cn", help="发件邮箱")
    parser.add_argument("--passwd", help="SMTP 密码/授权码（如不传则交互输入）")
    parser.add_argument("--subject", default="账号及口令通知", help="邮件主题")
    parser.add_argument("--reply-to", help="回复地址（可选）")
    parser.add_argument("--template", help="邮件模板文件路径（替代默认模板，支持 {email} {password}）")
    parser.add_argument("--delay", type=float, default=1.0, help="每封邮件间隔秒数（默认 1s）")
    parser.add_argument("--retry", type=int, default=3, help="失败重试次数（默认 3）")
    parser.add_argument("--test", action="store_true", help="测试模式：只给发件人自己发一封测试邮件")

    args = parser.parse_args()

    # ─── 检查文件 ───
    if not os.path.exists(args.file):
        logger.error(f"❌ 文件不存在: {args.file}")
        sys.exit(1)

    # ─── 读取模板 ───
    if args.template:
        with open(args.template, "r", encoding="utf-8") as f:
            template = f.read()
        logger.info(f"📝 使用自定义模板: {args.template}")
    else:
        template = DEFAULT_TEMPLATE
        logger.info("📝 使用默认模板")

    # ─── 获取密码 ───
    sender_pass = args.passwd
    if not sender_pass:
        import getpass
        sender_pass = getpass.getpass(f"🔑 请输入 {args.sender} 的 SMTP 密码/授权码: ")

    # ─── 解析用户列表 ───
    users = parse_users(args.file)
    if not users:
        logger.error("❌ 未识别到有效用户数据")
        sys.exit(1)
    logger.info(f"📋 共读取到 {len(users)} 个用户")

    # ─── 测试发送 ───
    if args.test:
        content = template.format(email=args.sender, password="123456")
        server = None
        try:
            server = build_smtp(args.smtp, args.port, args.sender, sender_pass)
            send_mail(server, args.sender, args.sender, f"[测试] {args.subject}", content, args.reply_to)
            logger.info(f"✅ 测试邮件发送成功（已发送至 {args.sender}）")
        except Exception as e:
            logger.error(f"❌ 测试发送失败: {e}")
            sys.exit(1)
        finally:
            if server:
                server.quit()
        return

    # ─── 正式发送 ───
    total = len(users)
    success_count = 0
    failed_count = 0
    failed_users = []

    server = None
    try:
        server = build_smtp(args.smtp, args.port, args.sender, sender_pass)
        logger.info(f"✅ 登录成功！开始批量发送（共 {total} 封）...")
        print("─" * 50)

        for idx, user in enumerate(users, 1):
            email = user["email"]
            password = user["password"]
            content = template.format(email=email, password=password)

            ok, err = send_with_retry(
                server, args.sender, email,
                args.subject, content,
                reply_to=args.reply_to,
                max_retries=args.retry,
            )

            if ok:
                success_count += 1
                logger.info(f"  [{idx}/{total}] ✅ {email}")
            else:
                failed_count += 1
                failed_users.append({"email": email, "error": err})
                logger.error(f"  [{idx}/{total}] ❌ {email} → {err}")

            # 发送间隔
            if idx < total:
                time.sleep(args.delay)

    except smtplib.SMTPAuthenticationError:
        logger.error("❌ SMTP 认证失败，请检查邮箱地址和密码/授权码是否正确")
        sys.exit(1)
    except Exception as e:
        logger.error(f"❌ 连接错误: {e}")
        sys.exit(1)
    finally:
        if server:
            server.quit()

    # ─── 汇总 ───
    print("═" * 50)
    logger.info(f"📊 发送汇总:")
    logger.info(f"   总  数：{total}")
    logger.info(f"   成  功：{success_count}")
    logger.info(f"   失  败：{failed_count}")

    if failed_users:
        print()
        logger.warning("📋 失败人员列表:")
        for fu in failed_users:
            logger.warning(f"   ❌ {fu['email']} → {fu['error']}")
        # 写入失败日志
        log_path = f"failed_{datetime.now().strftime('%Y%m%d_%H%M%S')}.txt"
        with open(log_path, "w", encoding="utf-8") as f:
            for fu in failed_users:
                f.write(f"{fu['email']}\t{fu['error']}\n")
        logger.info(f"📁 失败详情已保存至: {log_path}")

    if failed_count == 0:
        logger.info("🎉 全部发送成功！")
    elif success_count > 0:
        logger.info(f"⚠️ 部分失败，请检查失败列表重发")


if __name__ == "__main__":
    main()