"""Device Manager 능력등급/정밀도/오버라이드 결정 로직 (계획 §8 unit).

실하드웨어는 T0만 밟으므로 T1~T3은 합성 VRAM 값으로 검증.
"""
from __future__ import annotations

from luke_scribe.devices import manager as m
from luke_scribe.devices.manager import DeviceManager
from luke_scribe.devices.profile import CapabilityTier
from luke_scribe.devices.vram_probe import GpuInfo


def _patch(monkeypatch, gpus: list[GpuInfo]) -> None:
    monkeypatch.setattr(m, "probe_gpus", lambda: gpus)
    monkeypatch.setattr(m, "probe_ram_mb", lambda: 16000)
    monkeypatch.setattr(m, "probe_disk_free_mb", lambda path=".": 100000)


def _gpu(cc: tuple[int, int], free: int, name: str = "TestGPU") -> GpuInfo:
    return GpuInfo(0, name, cc, free + 100, free)


def test_no_gpu_is_t0_cpu(monkeypatch):
    _patch(monkeypatch, [])
    p = DeviceManager.detect()
    assert p.kind == "cpu"
    assert p.tier == CapabilityTier.T0_CPU
    assert p.compute_type == "int8"


def test_weak_pascal_downgrades_to_cpu(monkeypatch):
    # GTX 1050: cc6.1, free 1990 → turbo(int8, 2340MB 헤드룸) 부족 → CPU 강등
    _patch(monkeypatch, [_gpu((6, 1), 1990, "GTX 1050")])
    p = DeviceManager.detect()
    assert p.tier == CapabilityTier.T0_CPU
    assert p.kind == "cpu"
    assert p.vram_free_mb == 1990  # GPU 정보는 보존(투명성)
    assert any("강등" in n for n in p.notes)


def test_t1_turbo_only(monkeypatch):
    # cc7.5, free 6000 → int8_float16; turbo 적재 OK, large-v3 무리
    _patch(monkeypatch, [_gpu((7, 5), 6000)])
    p = DeviceManager.detect()
    assert p.tier == CapabilityTier.T1_TURBO_GPU
    assert p.compute_type == "int8_float16"
    assert p.served_models["batch"].startswith("large-v3-turbo")


def test_t2_swap(monkeypatch):
    # cc7.5, free 16000 → float16; turbo·large-v3 각각 OK, 동시상주는 불가
    _patch(monkeypatch, [_gpu((7, 5), 16000)])
    p = DeviceManager.detect()
    assert p.tier == CapabilityTier.T2_SWAP
    assert p.compute_type == "float16"
    assert "swap" in p.served_models["batch"]


def test_t3_coresident(monkeypatch):
    # A100급: cc8.0, free 40000 → float16; turbo+large-v3 동시상주
    _patch(monkeypatch, [_gpu((8, 0), 40000, "A100")])
    p = DeviceManager.detect()
    assert p.tier == CapabilityTier.T3_CORESIDENT
    assert p.compute_type == "float16"
    assert p.served_models["batch"] == "large-v3@cuda"
    assert p.max_workers >= 1


def test_force_cpu_override(monkeypatch):
    _patch(monkeypatch, [_gpu((8, 0), 40000)])
    p = DeviceManager.detect(force_device="cpu")
    assert p.tier == CapabilityTier.T0_CPU
    assert p.kind == "cpu"


def test_workers_override(monkeypatch):
    _patch(monkeypatch, [_gpu((8, 0), 40000)])
    p = DeviceManager.detect(workers_override=3)
    assert p.max_workers == 3