Initial commit: Dabit Time Manager project

Python-based time management application with UDP discovery,
TCP protocol communication, time sync, and drift monitoring.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

network/tcp_protocol.py

@@ -0,0 +1,77 @@
+"""ASCII 프로토콜 (시간 동기화 cmd30, 시간 읽기 cmd31)"""
+
+import socket
+from datetime import datetime
+
+from config import TCP_TIMEOUT, TCP_RECV_BUFFER, PROTOCOL_ENCODING
+from utils.time_format import datetime_to_protocol, protocol_to_datetime
+
+
+def sync_time(ip: str, port: int, dt: datetime | None = None) -> tuple[bool, str]:
+    """컨트롤러에 PC 시간 동기화 (명령 30).
+
+    패킷: ![0030YYMMDDdHHMMSS!]
+    예시: ![003026020912 30229!]  (2026-02-09 월 23:02:29)
+    응답: ![00300!] (성공) / ![0030F!] (실패)
+
+    Returns: (성공여부, 메시지)
+    """
+    if dt is None:
+        dt = datetime.now()
+
+    time_str = datetime_to_protocol(dt)
+    cmd = f"![0030{time_str}!]"
+
+    try:
+        resp = _tcp_send_recv(ip, port, cmd)
+    except Exception as e:
+        return False, f"연결 실패: {e}"
+
+    if "![00300!]" in resp:
+        return True, "동기화 성공"
+    elif "![0030F!]" in resp:
+        return False, "동기화 실패 (컨트롤러 응답 F)"
+    else:
+        return False, f"알 수 없는 응답: {resp}"
+
+
+def read_time(ip: str, port: int) -> tuple[datetime | None, datetime, datetime, str]:
+    """컨트롤러 시간 읽기 (명령 31).
+
+    패킷: ![0031!]
+    응답: ![0031YYMMDDdHHMMSS!]  (13자 시간 데이터)
+
+    Returns: (컨트롤러시간 | None, PC시간_before, PC시간_after, 에러메시지)
+    """
+    cmd = "![0031!]"
+
+    pc_before = datetime.now()
+    try:
+        resp = _tcp_send_recv(ip, port, cmd)
+    except Exception as e:
+        pc_after = datetime.now()
+        return None, pc_before, pc_after, f"연결 실패: {e}"
+    pc_after = datetime.now()
+
+    # 응답 파싱: ![0031YYMMDDdHHMMSS!]
+    # "![0031" 뒤에 13자의 시간 데이터
+    try:
+        start = resp.index("![0031") + 6
+        time_data = resp[start:start + 13]
+        ctrl_time = protocol_to_datetime(time_data)
+        return ctrl_time, pc_before, pc_after, ""
+    except (ValueError, IndexError) as e:
+        return None, pc_before, pc_after, f"응답 파싱 실패: {resp} ({e})"
+
+
+def _tcp_send_recv(ip: str, port: int, cmd: str) -> str:
+    """TCP 연결하여 명령 전송 후 응답 수신."""
+    sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+    sock.settimeout(TCP_TIMEOUT)
+    try:
+        sock.connect((ip, port))
+        sock.sendall(cmd.encode(PROTOCOL_ENCODING))
+        resp = sock.recv(TCP_RECV_BUFFER)
+        return resp.decode(PROTOCOL_ENCODING, errors="replace")
+    finally:
+        sock.close()