"""End-to-end test over a pseudo-terminal, with no RFID hardware.

The test owns the master side of a PTY, points the CLI at the slave side and
writes real RDM6300 frames. This exercises the same code path a physical
reader would: serial open -> byte stream -> parse -> callback -> stdout.
"""

import json
import os
import pty
import signal
import subprocess
import sys
import threading
import time

import pytest

from rdm_card_reader.card import CONFIG_CARD_VALUE

from .test_protocol import encode_stream, encode_frame  # noqa: F401

ROOT = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
SRC = os.path.join(ROOT, "src")

TIMEOUT = 15.0


class ReaderProcess:
    """Run the CLI against a PTY and collect its stdout in the background."""

    def __init__(self, extra_args=()):
        self.master, slave = pty.openpty()
        self.port = os.ttyname(slave)
        env = dict(os.environ)
        env["PYTHONPATH"] = SRC + os.pathsep + env.get("PYTHONPATH", "")
        self.proc = subprocess.Popen(
            [sys.executable, "-u", "-m", "rdm_card_reader",
             "--port", self.port, "--heartbeat", "0.3", *extra_args],
            cwd=ROOT, env=env, stdout=subprocess.PIPE,
            stderr=subprocess.STDOUT, text=True, bufsize=1,
            start_new_session=True,
        )
        self.lines = []
        self._lock = threading.Lock()
        self._thread = threading.Thread(target=self._pump, daemon=True)
        self._thread.start()

    def _pump(self):
        for line in self.proc.stdout:
            with self._lock:
                self.lines.append(line.rstrip())

    def output(self):
        with self._lock:
            return "\n".join(self.lines)

    def send(self, frame):
        os.write(self.master, b"\x02" + frame + b"\x03")

    def wait_for(self, needle, timeout=TIMEOUT):
        deadline = time.time() + timeout
        while time.time() < deadline:
            if needle in self.output():
                return True
            time.sleep(0.05)
        return False

    def __enter__(self):
        self.wait_for("waiting for cards")
        return self

    def __exit__(self, *exc):
        try:
            os.killpg(os.getpgid(self.proc.pid), signal.SIGINT)
        except Exception:
            pass
        try:
            self.proc.wait(timeout=5)
        except Exception:
            self.proc.kill()
        self._thread.join(timeout=3)
        for fd in (self.master, self.proc.stdout):
            try:
                fd.close()
            except Exception:
                pass
        return False


@pytest.mark.skipif(sys.platform != "linux", reason="PTY test is Linux only")
def test_card_insert_and_remove_are_reported():
    card_id = 0x00C4A0B5
    frame = encode_frame(card_id)

    with ReaderProcess() as rp:
        deadline = time.time() + TIMEOUT
        while time.time() < deadline and not rp.wait_for("CARD INSERTED", 0.2):
            rp.send(frame)

        assert rp.wait_for("CARD INSERTED"), rp.output()
        assert rp.wait_for("CARD REMOVED")

    text = rp.output()
    assert rp.port in text
    assert str(card_id) in text
    assert "0x00C4A0B5" in text
    assert "222" in text          # checksum = 0xDE
    assert "0x0F" in text         # type
    assert "True" in text         # valid


@pytest.mark.skipif(sys.platform != "linux", reason="PTY test is Linux only")
def test_corrupt_checksum_is_reported_as_invalid():
    good = bytearray(encode_frame(0x1A2B3C4D))
    good[-1] = ord("0")  # break the checksum
    bad = bytes(good)

    with ReaderProcess() as rp:
        deadline = time.time() + TIMEOUT
        while time.time() < deadline and not rp.wait_for("INVALID CARD", 0.2):
            rp.send(bad)

    assert "INVALID CARD" in rp.output()
    assert "checksum mismatch" in rp.output()


@pytest.mark.skipif(sys.platform != "linux", reason="PTY test is Linux only")
def test_json_mode_emits_machine_readable_events():
    with ReaderProcess(extra_args=("--json",)) as rp:
        deadline = time.time() + TIMEOUT
        while time.time() < deadline and not rp.wait_for('"event"', 0.2):
            rp.send(encode_frame(0x00C4A0B5))

    payloads = [
        json.loads(line)
        for line in rp.output().splitlines()
        if line.strip().startswith("{")
    ]
    assert payloads, rp.output()
    assert any(p["event"] == "card_inserted" for p in payloads)
    assert any(p["id"] == 0x00C4A0B5 for p in payloads)
    assert all(p["port"] == rp.port for p in payloads)


@pytest.mark.skipif(sys.platform != "linux", reason="PTY test is Linux only")
def test_config_card_is_annotated():
    with ReaderProcess() as rp:
        deadline = time.time() + TIMEOUT
        while time.time() < deadline and not rp.wait_for("config card", 0.2):
            rp.send(encode_frame(CONFIG_CARD_VALUE))

    assert "config card" in rp.output()


@pytest.mark.skipif(sys.platform != "linux", reason="PTY test is Linux only")
def test_removal_after_heartbeat_expires():
    with ReaderProcess() as rp:
        deadline = time.time() + TIMEOUT
        while time.time() < deadline and not rp.wait_for("CARD INSERTED", 0.2):
            rp.send(encode_frame(0x00C4A0B5))
        # stop sending and let the 0.3 s heartbeat lapse
        assert rp.wait_for("CARD REMOVED", timeout=5)

    assert "CARD REMOVED" in rp.output()