import os
import sys
import time
import socket
import struct
import ctypes

ROOT = os.path.abspath(os.path.join(os.path.dirname(__file__), '..'))
if ROOT not in sys.path:
    sys.path.insert(0, ROOT)

from pymsc.core.app_controller import AppController
from pymsc.lib1553.structures import Udp1553Message, Udp1553Header, CommandWord
from pymsc.lib1553.constants import Marker
from pymsc.lib1553.messages.a3_graphic_setting import MsgA3Payload


def build_a3_packet():
    payload = MsgA3Payload()
    payload.graphic_order = 7
    payload.time_to_go = 42
    payload_bytes = bytes(payload)

    cw = CommandWord(wc=len(payload_bytes)//2, sa=3, tr=1, rt=20)
    wrapper = Udp1553Message(marker=Marker.CTRL_BEGIN, cw=cw, sw=0, error_code=0)
    cw_raw = int(wrapper.cw.raw)
    inv = (~cw_raw) & 0xFFFF

    packet = bytes(Udp1553Header()) + bytes(wrapper) + payload_bytes + struct.pack('<H', inv) + struct.pack('<H', Marker.CTRL_END) + struct.pack('<H', Marker.END_1553)
    return packet


def test_appcontroller_receives_a3():
    c = AppController()
    c.start()
    try:
        time.sleep(0.05)
        pkt = build_a3_packet()
        sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
        sock.sendto(pkt, ('127.0.0.1', c.udp_recv_port))

        # wait for monitor queue item
        got = None
        timeout = time.time() + 2.0
        while time.time() < timeout:
            try:
                item = c.monitor_queue.get(timeout=0.2)
                # expect label 'A3' somewhere
                if isinstance(item, tuple) and len(item) >= 3 and item[1] == 'A3':
                    got = item
                    break
            except Exception:
                pass

        assert got is not None, 'Did not receive decoded A3 in monitor_queue'
        # if payload decoded, third element contains JSON string or dict
        assert 'graphic_order' in str(got[3]) or 'CW' in str(got[3])
    finally:
        c.stop()