"""Preloading must leave ggml's runtime-selected CPU variants to ggml (#44)."""

from pathlib import Path
from unittest.mock import patch

from vocalinux.utils import pywhispercpp_loader


def _preload_names(tmp_path: Path, *names: str) -> list[str]:
    """Run the preloader over ``names`` in one directory and return what it dlopens."""
    for name in names:
        (tmp_path / name).write_bytes(b"")
    loaded: list[str] = []

    def record(path: str, mode: int = 0) -> object:
        loaded.append(Path(path).name)
        return object()

    with (
        patch.object(pywhispercpp_loader, "find_shared_library_dirs", return_value=[str(tmp_path)]),
        patch.object(pywhispercpp_loader, "_PRELOADED_LIBS", []),
        patch.object(pywhispercpp_loader.ctypes, "CDLL", side_effect=record),
    ):
        pywhispercpp_loader.preload_shared_libraries()
    return loaded


def test_preload_leaves_runtime_cpu_variants_to_ggml(tmp_path: Path) -> None:
    """Variants share one symbol table; preloading them RTLD_GLOBAL would interpose them."""
    loaded = _preload_names(
        tmp_path,
        "libggml.so.0",
        "libggml-base.so.0",
        "libggml-cpu-x64.so",
        "libggml-cpu-haswell.so",
        "libggml-vulkan.so",
        "libwhisper.so.1",
    )

    assert not [name for name in loaded if name.startswith("libggml-cpu-")]
    assert {"libggml.so.0", "libggml-base.so.0", "libggml-vulkan.so", "libwhisper.so.1"} <= set(
        loaded
    )


def test_preload_keeps_the_single_cpu_library_of_a_non_variant_build(tmp_path: Path) -> None:
    """Without GGML_CPU_ALL_VARIANTS the CPU backend is a dependency and must be preloaded."""
    loaded = _preload_names(tmp_path, "libggml.so.0", "libggml-cpu.so")

    assert "libggml-cpu.so" in loaded