# -*- coding: utf-8 -*-
"""Tests de `monitor_estado.lock` — instancia unica (RF-22)."""

import json

import monitor_estado.lock as lock


def test_lock_impide_segunda_instancia(tmp_path, monkeypatch):
    """Una segunda adquisicion con la primera viva debe fallar (RF-22)."""
    monkeypatch.setattr(lock, "LOCK_PATH", tmp_path / ".lock")

    assert lock.adquirir() is True
    # Misma PID viva -> la segunda instancia no arranca.
    assert lock.adquirir() is False

    lock.liberar()
    assert not (tmp_path / ".lock").exists()
    assert lock.adquirir() is True
    lock.liberar()


def test_lock_recupera_lock_caducado(tmp_path, monkeypatch):
    """Un lock de un PID muerto no debe bloquear (se recupera)."""
    ruta = tmp_path / ".lock"
    monkeypatch.setattr(lock, "LOCK_PATH", ruta)
    ruta.write_text(json.dumps({"pid": 999999, "arranque": "2026-01-01T00:00:00"}), encoding="utf-8")

    assert lock.adquirir() is True
    lock.liberar()


def test_lock_liberar_no_borra_lock_ajeno(tmp_path, monkeypatch):
    """`liberar` solo elimina el lock si es de nuestro propio PID."""
    ruta = tmp_path / ".lock"
    monkeypatch.setattr(lock, "LOCK_PATH", ruta)
    ruta.write_text(json.dumps({"pid": 999999, "arranque": "x"}), encoding="utf-8")

    lock.liberar()
    assert ruta.exists()  # no era nuestro -> se respeta