from __future__ import annotations


def inventory_failure(
    component_mode: str, *, orbit_count: int, adaln_count: int, cache_count: int
) -> str | None:
    if cache_count:
        return "full dequantized caches present after clean load"
    low_bit_count = orbit_count + adaln_count
    if component_mode == "w4a4" and low_bit_count == 0:
        return "no low-bit modules restored"
    if component_mode == "source_copy" and low_bit_count:
        return "unexpected low-bit modules in source component copy"
    if component_mode not in {"w4a4", "source_copy"}:
        return f"unknown component mode: {component_mode}"
    return None