"""
邮件接收 API 服务器
====================
接收 Cloudflare Email Routing 转发的邮件，供注册服务查询。

端点:
  POST /webhook          — Cloudflare 转发邮件到这里
  GET  /check/<email>    — 查询某邮箱的验证码
  GET  /domains          — 返回可用域名
  GET  /health           — 健康检查

用法:
  bash start.sh --email-service
  EMAIL_DOMAIN=your.domain bash start.sh --email-service --port 8080
"""
import os, re, json, time, sys
try:
    from dotenv import load_dotenv
    load_dotenv()
except ImportError:
    pass
from http.server import HTTPServer, ThreadingHTTPServer, BaseHTTPRequestHandler
from urllib.parse import urlparse, parse_qs
from threading import Lock

# 配置
DEFAULT_DOMAIN = os.environ.get("EMAIL_DOMAIN", "")
DEFAULT_PORT = 8080

# 存储
emails = {}  # {email_address: [{"code": "ABC123", "time": timestamp, "raw": "..."}]}
emails_lock = Lock()

# 清理过期邮件（5 分钟）
def cleanup_old():
    now = time.time()
    with emails_lock:
        for addr in list(emails.keys()):
            emails[addr] = [e for e in emails[addr] if now - e['time'] < 300]
            if not emails[addr]:
                del emails[addr]


def extract_code(text):
    """从邮件内容提取验证码（ABC-DEF 或 ABCDEF 格式）"""
    # 格式1: ABC-DEF
    m = re.search(r'>([A-Z0-9]{3}-[A-Z0-9]{3})<', text)
    if m:
        return m.group(1).replace('-', '')
    # 格式2: 直接 6 位
    m = re.search(r'>([A-Z0-9]{6})<', text)
    if m:
        return m.group(1)
    # 格式3: 正文中的 6 位
    m = re.search(r'\b([A-Z0-9]{3}-?[A-Z0-9]{3})\b', text)
    if m:
        return m.group(1).replace('-', '')
    return None


class EmailHandler(BaseHTTPRequestHandler):
    def do_POST(self):
        if self.path == '/webhook':
            content_length = int(self.headers.get('Content-Length', 0))
            body = self.rfile.read(content_length).decode('utf-8')

            try:
                data = json.loads(body)
            except:
                data = {}

            # Cloudflare Email Routing 格式
            to_addr = data.get('to', data.get('recipient', ''))
            from_addr = data.get('from', data.get('sender', ''))
            subject = data.get('subject', '')
            text = data.get('text', '')
            html = data.get('html', '')

            # 提取验证码
            content = f"{subject}\n{text}\n{html}"
            code = extract_code(content)

            if to_addr and code:
                with emails_lock:
                    if to_addr not in emails:
                        emails[to_addr] = []
                    emails[to_addr].append({
                        'code': code,
                        'time': time.time(),
                        'from': from_addr,
                        'subject': subject
                    })
                print(f'[+] {to_addr} code={code}', flush=True)

            self.send_response(200)
            self.send_header('Content-Type', 'application/json')
            self.end_headers()
            self.wfile.write(json.dumps({"ok": True, "code": code}).encode())
        else:
            self.send_response(404)
            self.end_headers()

    def do_GET(self):
        parsed = urlparse(self.path)
        path = parsed.path

        if path == '/health':
            self._json({"status": "ok", "emails": len(emails)})

        elif path == '/domains':
            self._json({"domains": [DEFAULT_DOMAIN]})

        elif path.startswith('/check/'):
            addr = path[7:]  # 去掉 /check/
            cleanup_old()
            with emails_lock:
                items = emails.get(addr, [])
                if items:
                    # 返回最新的验证码
                    latest = items[-1]
                    self._json({"code": latest['code'], "from": latest['from']})
                else:
                    self._json({"code": None})

        elif path == '/list':
            # 列出所有有邮件的地址（调试用）
            cleanup_old()
            with emails_lock:
                result = {addr: len(msgs) for addr, msgs in emails.items()}
            self._json(result)

        else:
            self.send_response(404)
            self.end_headers()

    def _json(self, data):
        body = json.dumps(data).encode()
        self.send_response(200)
        self.send_header('Content-Type', 'application/json')
        self.send_header('Content-Length', str(len(body)))
        self.end_headers()
        self.wfile.write(body)

    def log_message(self, format, *args):
        print(f"[HTTP] {args[0] if args else format}", flush=True)


def main():
    global DEFAULT_DOMAIN
    port = DEFAULT_PORT
    domain = DEFAULT_DOMAIN

    for i, arg in enumerate(sys.argv[1:]):
        if arg == '--port' and i + 2 <= len(sys.argv):
            port = int(sys.argv[i + 2])
        if arg == '--domain' and i + 2 <= len(sys.argv):
            domain = sys.argv[i + 2]

    DEFAULT_DOMAIN = domain

    print(f"[*] Email server starting on :{port}", flush=True)
    print(f"[*] Domain: {domain}", flush=True)
    print(f"[*] Webhook: http://0.0.0.0:{port}/webhook", flush=True)
    print(f"[*] Check: http://localhost:{port}/check/<email>", flush=True)

    server = ThreadingHTTPServer(('0.0.0.0', port), EmailHandler)
    server.serve_forever()


if __name__ == "__main__":
    main()