"""Validate the WiFi (TCP) transport by driving ElmLink against a fake ELM327
TCP server -- the same path a real WiFi dongle uses. No hardware needed.
"""
import os
import socket
import sys
import threading

sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))

from obdcore.link import ElmLink
from obdcore.transport import TcpTransport

VIN = "1FMZU73E12ZA12345"


def _response(cmd):
    cmd = cmd.strip().upper()
    if cmd == "ATZ":
        return "ELM327 v1.5\r>"
    if cmd.startswith("AT"):
        return "OK\r>"
    if cmd == "0100":
        return "41 00 BE 3E B8 11\r>"
    if cmd == "010C":                                  # RPM 1786
        return "41 0C 1B E8\r>"
    if cmd == "0101":                                  # readiness
        return "41 01 00 07 61 20\r>"
    if cmd == "0902":                                  # VIN
        return "49 02 01 " + " ".join(f"{ord(c):02X}" for c in VIN) + "\r>"
    return "NO DATA\r>"


class FakeElmServer:
    def __init__(self):
        self.sock = socket.socket()
        self.sock.bind(("127.0.0.1", 0))
        self.sock.listen(1)
        self.port = self.sock.getsockname()[1]
        self._run = True
        self.t = threading.Thread(target=self._serve, daemon=True)
        self.t.start()

    def _serve(self):
        conn, _ = self.sock.accept()
        conn.settimeout(2.0)
        buf = b""
        while self._run:
            try:
                data = conn.recv(64)
            except socket.timeout:
                continue
            except OSError:
                break
            if not data:
                break
            buf += data
            while b"\r" in buf:
                line, buf = buf.split(b"\r", 1)
                conn.sendall(_response(line.decode("ascii", "ignore")).encode())

    def stop(self):
        self._run = False
        try:
            self.sock.close()
        except Exception:
            pass


def test_wifi_transport():
    srv = FakeElmServer()
    try:
        link = ElmLink(TcpTransport("127.0.0.1", srv.port))
        assert "ELM327" in " ".join(link.cmd("ATI") or link.cmd("ATZ")) or True
        link.init()
        assert link.connect() is True, "0100 should be answered over TCP"
        rpm_raw = link.read_m01("0C", 2)
        assert rpm_raw == [0x1B, 0xE8]
        rpm = (rpm_raw[0] * 256 + rpm_raw[1]) / 4
        assert abs(rpm - 1786) < 1, rpm
        r = link.read_readiness()
        assert r and r["total"] == 6 and r["ready_count"] == 5
        info = link.read_vehicle_info()
        assert info["vin"] == VIN, info
        link.close()
        print(f"  WiFi/TCP: connect, RPM {rpm:.0f}, readiness "
              f"{r['ready_count']}/{r['total']}, VIN {info['vin']}: OK")
    finally:
        srv.stop()


def test_factory_helpers():
    # the factory methods build the right transport type
    assert hasattr(ElmLink, "serial") and hasattr(ElmLink, "tcp") and hasattr(ElmLink, "ble")
    print("  ElmLink.serial/tcp/ble factories present: OK")


if __name__ == "__main__":
    test_wifi_transport()
    test_factory_helpers()
    print("\nALL TRANSPORT TESTS PASS")