---

import socket
import threading
import json
import time

import cv2
import numpy as np

HOST = '0.0.0.0'
CMD_PORT = 5001
SCAN_PORT = 5002
VIDEO_PORT = 5000

current_cmd = {"linear_x": 0.0, "angular_z": 0.0}
cmd_lock = threading.Lock()


def command_server():
    server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    server_socket.bind((HOST, CMD_PORT))
    server_socket.listen(1)
    print(f"жду подключения робота на порту {CMD_PORT}...")

    conn, addr = server_socket.accept()
    print(f"робот подключился: {addr}")

    try:
        while True:
            with cmd_lock:
                data = json.dumps(current_cmd).encode('utf-8')
            conn.sendall(len(data).to_bytes(4, 'big') + data)
            time.sleep(0.1)
    except (ConnectionResetError, BrokenPipeError, OSError):
        print("робот отключился")
    finally:
        conn.close()
        server_socket.close()


def recv_exact(sock, n):
    buf = b''
    while len(buf) < n:
        chunk = sock.recv(n - len(buf))
        if not chunk:
            return None
        buf += chunk
    return buf


def video_server():
    server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    server_socket.bind((HOST, VIDEO_PORT))
    server_socket.listen(1)
    print(f"жду подключения робота на порту {VIDEO_PORT} (видео)...")

    conn, addr = server_socket.accept()
    print(f"робот подключился (видео): {addr}")

    try:
        while True:
            size_bytes = recv_exact(conn, 4)
            if size_bytes is None:
                break
            frame_size = int.from_bytes(size_bytes, byteorder='big')

            frame_data = recv_exact(conn, frame_size)
            if frame_data is None:
                break

            nparr = np.frombuffer(frame_data, np.uint8)
            frame = cv2.imdecode(nparr, cv2.IMREAD_COLOR)
            if frame is not None:
                cv2.imshow("Камера робота", frame)
                cv2.waitKey(1)
    except (ConnectionResetError, OSError):
        print("робот отключился (видео)")
    finally:
        conn.close()
        server_socket.close()
        cv2.destroyAllWindows()


scan_conn = None
scan_lock = threading.Lock()


def scan_server():
    global scan_conn
    server_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    server_socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
    server_socket.bind((HOST, SCAN_PORT))
    server_socket.listen(1)
    print(f"жду подключения робота на порту {SCAN_PORT} (лидар)...")

    conn, addr = server_socket.accept()
    print(f"робот подключился (лидар): {addr}")
    with scan_lock:
        scan_conn = conn


def request_distance():
    with scan_lock:
        conn = scan_conn
    if conn is None:
        print("канал лидара ещё не подключен")
        return
    try:
        conn.sendall(b'get')
        size_bytes = recv_exact(conn, 4)
        if size_bytes is None:
            print("робот не ответил")
            return
        msg_len = int.from_bytes(size_bytes, 'big')
        payload = recv_exact(conn, msg_len)
        data = json.loads(payload.decode('utf-8'))
        print(f"расстояние до ближайшей стены: {data['distance']:.2f} м")
    except (ConnectionResetError, OSError):
        print("канал лидара оборван")


def keyboard_input():
    print("""
i — вперёд      , — назад
j — влево       l — вправо
k — стоп
1 — расстояние до ближайшей стенки
q — выход
""")
    SPEED = 0.15
    TURN = 0.3

    try:
        while True:
            key = input(">> ").strip().lower()
            if key == '1':
                request_distance()
                continue
            with cmd_lock:
                if key == 'i':
                    current_cmd["linear_x"] = SPEED
                    current_cmd["angular_z"] = 0.0
                elif key == ',':
                    current_cmd["linear_x"] = -SPEED
                    current_cmd["angular_z"] = 0.0
                elif key == 'j':
                    current_cmd["linear_x"] = 0.0
                    current_cmd["angular_z"] = TURN
                elif key == 'l':
                    current_cmd["linear_x"] = 0.0
                    current_cmd["angular_z"] = -TURN
                elif key == 'k':
                    current_cmd["linear_x"] = 0.0
                    current_cmd["angular_z"] = 0.0
                elif key == 'q':
                    break
    except KeyboardInterrupt:
        pass
    finally:
        with cmd_lock:
            current_cmd["linear_x"] = 0.0
            current_cmd["angular_z"] = 0.0
        print("остановка, выход")


if __name__ == '__main__':
    threading.Thread(target=command_server, daemon=True).start()
    threading.Thread(target=scan_server, daemon=True).start()
    threading.Thread(target=video_server, daemon=True).start()
    keyboard_input()