"""Tests del resolver de Python runtime (issue 0033 fase B).

El resolver vive en C++ (jobs.cpp::cached_python_runtime). Como
pytest no puede llamarlo directo, los tests verifican el
comportamiento via efectos observables:

  1. La estructura del freeze script y su lock.
  2. Que el binario, al arrancar, loggea la procedencia del runtime
     (kind=embedded|registry_venv|env|system).

El test del binario solo corre si el .exe esta compilado para Linux
en el path esperado — si no, se skipea.
"""
from __future__ import annotations

import os
import shutil
import subprocess
from pathlib import Path

import pytest

from conftest import REGISTRY_ROOT, APP_DIR_SRC


GRAPH_EXPLORER_BIN = (
    REGISTRY_ROOT / "cpp" / "build" / "linux" / "apps"
    / "graph_explorer" / "graph_explorer"
)


def _runtime_log_line(stdout: str) -> str | None:
    for line in stdout.splitlines():
        if line.startswith("[jobs] python runtime:"):
            return line
    return None


@pytest.mark.skipif(not GRAPH_EXPLORER_BIN.exists(),
                     reason="binario graph_explorer no compilado")
def test_resolver_falls_back_to_registry_venv_when_no_embed(tmp_path):
    """Sin runtime/ junto al exe, debe caer a registry_venv."""
    # Copiamos el binario a tmp_path (sin runtime/) y lo arrancamos
    # desde el repo root (donde existe projects/default).
    bin_copy = tmp_path / "graph_explorer"
    shutil.copy(GRAPH_EXPLORER_BIN, bin_copy)
    bin_copy.chmod(0o755)

    proc = subprocess.run(
        [str(bin_copy)],
        cwd=str(REGISTRY_ROOT / "cpp"),
        capture_output=True, text=True, timeout=4,
        env={**os.environ, "DISPLAY": ""},  # forzamos GLFW fail rapido
    )
    line = _runtime_log_line(proc.stdout)
    assert line is not None, f"no se logueo runtime: {proc.stdout[-500:]}"
    assert "kind=registry_venv" in line, line
    assert "wsl=0" in line, line


@pytest.mark.skipif(not GRAPH_EXPLORER_BIN.exists(),
                     reason="binario graph_explorer no compilado")
def test_resolver_picks_embedded_when_runtime_present(tmp_path):
    """Con runtime/ junto al exe, debe elegir embedded."""
    bin_copy = tmp_path / "graph_explorer"
    shutil.copy(GRAPH_EXPLORER_BIN, bin_copy)
    bin_copy.chmod(0o755)

    # Faux runtime: solo necesita un ejecutable en bin/python3.
    rt = tmp_path / "runtime" / "python" / "bin"
    rt.mkdir(parents=True)
    fake_py = rt / "python3"
    fake_py.write_text("#!/bin/bash\necho fake\n")
    fake_py.chmod(0o755)

    proc = subprocess.run(
        [str(bin_copy)],
        cwd=str(REGISTRY_ROOT / "cpp"),
        capture_output=True, text=True, timeout=4,
        env={**os.environ, "DISPLAY": ""},
    )
    line = _runtime_log_line(proc.stdout)
    assert line is not None, f"no se logueo runtime: {proc.stdout[-500:]}"
    assert "kind=embedded" in line, line
    assert str(fake_py) in line, line


@pytest.mark.skipif(not GRAPH_EXPLORER_BIN.exists(),
                     reason="binario graph_explorer no compilado")
def test_resolver_uses_fn_python_env_var(tmp_path):
    """FN_PYTHON tiene prioridad sobre el venv del registry."""
    bin_copy = tmp_path / "graph_explorer"
    shutil.copy(GRAPH_EXPLORER_BIN, bin_copy)
    bin_copy.chmod(0o755)

    fake = tmp_path / "my_python"
    fake.write_text("#!/bin/bash\necho fake\n")
    fake.chmod(0o755)

    proc = subprocess.run(
        [str(bin_copy)],
        cwd=str(REGISTRY_ROOT / "cpp"),
        capture_output=True, text=True, timeout=4,
        env={**os.environ, "DISPLAY": "", "FN_PYTHON": str(fake)},
    )
    line = _runtime_log_line(proc.stdout)
    assert line is not None, f"no se logueo runtime: {proc.stdout[-500:]}"
    assert "kind=env" in line, line
    assert str(fake) in line, line


def test_freeze_script_is_idempotent(tmp_path):
    """Llamadas consecutivas con mismas deps no rehacen el runtime."""
    fake_app = tmp_path / "app"
    fake_app.mkdir()
    (fake_app / "app.md").write_text(
        "---\nname: x\npython_runtime: true\n"
        "python_runtime_deps:\n  - requests\n---\n",
        encoding="utf-8")

    script = APP_DIR_SRC / "tools" / "freeze_python_runtime.sh"

    # 1ra ejecucion: deberia hacer todo el trabajo.
    proc1 = subprocess.run(
        [str(script), str(fake_app), "linux"],
        capture_output=True, text=True, timeout=120,
    )
    if proc1.returncode != 0:
        pytest.skip(f"freeze fallo (sin uv?): {proc1.stderr[:200]}")
    assert (fake_app / "runtime" / ".lock").exists()
    lock1 = (fake_app / "runtime" / ".lock").read_text()

    # 2da: con el .lock ya escrito, debe reportar "sin cambios".
    proc2 = subprocess.run(
        [str(script), str(fake_app), "linux"],
        capture_output=True, text=True, timeout=10,
    )
    assert proc2.returncode == 0, proc2.stderr
    assert "sin cambios" in proc2.stdout, proc2.stdout
    lock2 = (fake_app / "runtime" / ".lock").read_text()
    assert lock1 == lock2