"""Tests Supervisor/Launcher mit echten Kindprozessen (PLAN.md §6.1A, §26).

Keine Mocks: die Tests starten reale Python-Kindprozesse und prüfen
Start, kontrolliertes Beenden, Neustart nach Absturz, Crashloop-Erkennung
und Recovery-Markierung.
"""

from __future__ import annotations

import sys
import time
from pathlib import Path

import pytest
from hms_launcher import AppPaths, ProcessSpec, Supervisor, find_free_port


def _sleeper(seconds: float = 30.0) -> list[str]:
    """Kindprozess-Kommando, das `seconds` lang still läuft."""
    return [sys.executable, "-c", f"import time; time.sleep({seconds})"]


def _crasher() -> list[str]:
    """Kindprozess-Kommando, das sofort mit Code 1 endet."""
    return [sys.executable, "-c", "import sys; sys.exit(1)"]


def _wait_exit(state, timeout: float = 5.0) -> None:
    deadline = time.monotonic() + timeout
    while state.proc is not None and state.proc.poll() is None and time.monotonic() < deadline:
        time.sleep(0.02)


def _wait_file(path: Path, timeout: float = 5.0) -> None:
    deadline = time.monotonic() + timeout
    while not path.is_file() and time.monotonic() < deadline:
        time.sleep(0.01)
    assert path.is_file(), f"kindprozess schrieb {path} nicht"


def test_find_free_port_returns_usable_port() -> None:
    port = find_free_port()
    assert 1024 <= port <= 65535
    import socket

    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as sock:
        sock.bind(("127.0.0.1", port))


def test_start_and_running_state(tmp_path: Path) -> None:
    sup = Supervisor(AppPaths(root=tmp_path))
    sup.start(ProcessSpec(name="renderer", cmd=_sleeper()))
    try:
        assert sup.state("renderer").running
        assert sup.check()["renderer"] == "running"
    finally:
        sup.shutdown()
    assert sup.state("renderer").returncode is not None


def test_duplicate_start_rejected(tmp_path: Path) -> None:
    sup = Supervisor(AppPaths(root=tmp_path))
    sup.start(ProcessSpec(name="core", cmd=_sleeper()))
    try:
        with pytest.raises(RuntimeError, match="already running"):
            sup.start(ProcessSpec(name="core", cmd=_sleeper()))
    finally:
        sup.shutdown()


def test_controlled_stop_uses_terminate(tmp_path: Path) -> None:
    sup = Supervisor(AppPaths(root=tmp_path))
    sup.start(ProcessSpec(name="core", cmd=_sleeper(), stop_timeout_s=5.0))
    rc = sup.stop("core")
    try:
        assert rc is not None
        assert not sup.state("core").running
        # kontrolliert beendet → kein Neustart durch check()
        assert sup.check()["core"] == "stopped"
        # keine Recovery-Markierung bei sauberem Stop
        assert sup.consume_recovery_marker() == []
    finally:
        sup.shutdown()


def test_crash_triggers_restart(tmp_path: Path) -> None:
    sup = Supervisor(AppPaths(root=tmp_path))
    spec = ProcessSpec(
        name="core", cmd=_sleeper(0.2), max_restarts=3, restart_window_s=30.0
    )
    sup.start(spec)
    _wait_exit(sup.state("core"))
    result = sup.check()  # Absturz erkannt → Neustart
    assert result["core"] == "restarted"
    assert sup.state("core").running
    assert len(sup.state("core").restarts) == 1
    sup.shutdown()


def test_crashloop_detection_stops_restarting(tmp_path: Path) -> None:
    sup = Supervisor(AppPaths(root=tmp_path))
    spec = ProcessSpec(name="core", cmd=_crasher(), max_restarts=2, restart_window_s=60.0)
    sup.start(spec)
    _wait_exit(sup.state("core"))
    assert sup.check()["core"] == "restarted"  # Neustart 1
    _wait_exit(sup.state("core"))
    assert sup.check()["core"] == "restarted"  # Neustart 2
    _wait_exit(sup.state("core"))
    assert sup.check()["core"] == "crashloop"  # Schwelle erreicht (§26.2)
    assert sup.state("core").crashlooped
    # weiteres check() startet nicht mehr
    assert sup.check()["core"] == "crashloop"
    sup.shutdown()


def test_non_restartable_process_stays_down(tmp_path: Path) -> None:
    sup = Supervisor(AppPaths(root=tmp_path))
    sup.start(ProcessSpec(name="oneshot", cmd=_crasher(), restartable=False))
    _wait_exit(sup.state("oneshot"))
    assert sup.check()["oneshot"] == "stopped"
    assert not sup.state("oneshot").running


def test_recovery_marker_on_forced_kill(tmp_path: Path) -> None:
    """Kindprozess ignoriert SIGTERM → kill → Recovery-Markierung (§26.4).

    Der Kindprozess bestätigt die Handler-Registrierung über eine Ready-Datei;
    erst danach sendet der Test SIGTERM (keine Race Condition).
    """
    if sys.platform == "win32":
        return  # Signal-Ignorieren unter Windows nicht testbar
    ready = tmp_path / "ready.txt"
    ignore_term = (
        "import signal, time, sys\n"
        "signal.signal(signal.SIGTERM, lambda *a: None)\n"
        f"open(r'{ready}', 'w').write('ok')\n"
        "time.sleep(30)\n"
    )
    sup = Supervisor(AppPaths(root=tmp_path))
    sup.start(
        ProcessSpec(
            name="stubborn",
            cmd=[sys.executable, "-c", ignore_term],
            stop_timeout_s=0.3,
        )
    )
    _wait_file(ready)  # Handler aktiv, bevor SIGTERM gesendet wird
    rc = sup.stop("stubborn")
    assert rc is not None
    lines = sup.consume_recovery_marker()
    assert any("forced-kill stubborn" in line for line in lines)
    # Markierung nach dem Lesen gelöscht
    assert sup.consume_recovery_marker() == []


def test_shutdown_stops_all_processes(tmp_path: Path) -> None:
    sup = Supervisor(AppPaths(root=tmp_path))
    sup.start(ProcessSpec(name="renderer", cmd=_sleeper()))
    sup.start(ProcessSpec(name="core", cmd=_sleeper()))
    sup.shutdown()
    assert not sup.state("renderer").running
    assert not sup.state("core").running


def test_environment_gets_gstreamer_vars(tmp_path: Path) -> None:
    """Kindprozess erbt die portable GStreamer-Umgebung (§9.2, ADR-0002).

    Der Kindprozess schreibt beide Variablen in eine Datei (kein stdout-
    Piping nötig)."""
    paths = AppPaths(root=tmp_path)
    result_file = tmp_path / "env_result.txt"
    probe = (
        "import os\n"
        f"open(r'{result_file}', 'w').write(\n"
        "    os.environ.get('GST_PLUGIN_SYSTEM_PATH_1_0', 'MISSING')\n"
        "    + '|'\n"
        "    + os.environ.get('GST_PLUGIN_PATH_1_0', 'MISSING')\n"
        ")\n"
    )
    sup = Supervisor(paths)
    sup.start(
        ProcessSpec(name="envprobe", cmd=[sys.executable, "-c", probe], restartable=False)
    )
    _wait_exit(sup.state("envprobe"))
    _wait_file(result_file)
    content = result_file.read_text(encoding="utf-8")
    system_path, plugin_path = content.split("|", 1)
    assert system_path == ""  # System-Plugins unterdrückt (§9.2)
    assert plugin_path.endswith("gstreamer-1.0")  # gebündelte Plugin-Untermenge