"""ports.py 端口冻结测试(M1 设计 §4): Protocol 结构性检查 + Gate 快照校验。"""

import inspect
from typing import Any

import pytest

from polygateway.ports import (
    CacheBackend,
    EmbeddingTransport,
    GateDecision,
    GateState,
    GateUpdate,
    Middleware,
    OcrTransport,
    Permit,
    ProviderGate,
    RateLimiter,
    SourceSelector,
    StructuredOutputStrategy,
    TelemetryRecorder,
    TelemetryStatusProvider,
    Transport,
)
from polygateway.types import LLMResponse, SourceStats, TelemetryStatus


def _resp() -> LLMResponse:
    return LLMResponse("c", "t", "m", "p", 1, 2, 3, None, None, False, "cid")


class _DummyPermit:
    async def release(self) -> None: ...
    async def settle(self, actual_tokens: int) -> None: ...


class _DummyLimiter:
    async def try_acquire(self, source_key: str, est_tokens: int):
        return _DummyPermit()

    async def acquire(self, source_key: str, est_tokens: int):
        return _DummyPermit()

    async def source_stats(self, source_key: str):
        return SourceStats(0, 0, 0)

    async def mark_progress(self) -> None: ...
    async def progress_age_s(self) -> float:
        return 0.0


class _DummyGate:
    async def try_enter(self, source_name: str, owner: str):
        raise NotImplementedError

    async def record_success(self, entry):
        raise NotImplementedError

    async def record_failure(self, entry, reason: str, force_open: bool):
        raise NotImplementedError

    async def release_probe(self, entry):
        raise NotImplementedError

    async def retry_after_s(self, sources):
        return 0.0


class _DummyMw:
    async def __call__(self, request, call_next):
        return await call_next(request)


class _DummyTransport:
    async def complete(self, *, messages, source, stream, overlay, call_id, reasoning_effort):
        raise NotImplementedError


class _DummyCache:
    async def get(self, key: str):
        return None

    async def set(self, key: str, value: str, ttl_s: int) -> None: ...


class _DummySelector:
    def order(self, sources, stats):
        return list(sources)


class _DummyStrategy:
    def request_overlay(self, schema):
        return {}

    def parse(self, text: str) -> Any:
        return {}


class _DummyRecorder:
    async def record_llm_call(
        self,
        *,
        call_id,
        parent_call_id,
        session_id,
        model,
        provider,
        source_name,
        messages,
        response,
        thinking,
        prompt_tokens,
        completion_tokens,
        usage_source,
        latency_ms,
        ttft_ms,
        max_inter_token_ms,
        cache_hit,
        error,
        cost,
        cached_prompt_tokens,
        model_reported,
        sampling,
        reasoning_tokens,
        tenant_id,
        meta,
    ) -> None: ...


@pytest.mark.parametrize(
    ("impl", "protocol"),
    [
        (_DummyPermit(), Permit),
        (_DummyLimiter(), RateLimiter),
        (_DummyGate(), ProviderGate),
        (_DummyMw(), Middleware),
        (_DummyTransport(), Transport),
        (_DummyCache(), CacheBackend),
        (_DummySelector(), SourceSelector),
        (_DummyStrategy(), StructuredOutputStrategy),
        (_DummyRecorder(), TelemetryRecorder),
    ],
)
def test_protocols_are_runtime_checkable(impl, protocol):
    assert isinstance(impl, protocol)


class TestReasoningTierIsOnlyOnTheChatPort:
    """档位属于 chat 端口,且**只属于**它(Task 5b)。

    `@runtime_checkable` 只查方法名不查签名,故协议签名本身必须被显式断言——
    否则实现漏改一个参数,要到运行期调用才会以 `TypeError` 现形,而那时的现场
    离根因已经很远。
    """

    def test_chat_transport_carries_the_per_call_tier(self):
        params = inspect.signature(Transport.complete).parameters
        assert "reasoning_effort" in params
        # 不给默认值是有意的(与 TelemetryRecorder 同一既有约定): 库外无第三方
        # 实现者,写全签名成本为零,而默认值会把"漏传"变成静默的"不表态"
        assert params["reasoning_effort"].default is inspect.Parameter.empty

    @pytest.mark.parametrize(
        ("protocol", "method"),
        [
            (EmbeddingTransport, "embed"),
            (OcrTransport, "recognize_text"),
            (OcrTransport, "parse_layout"),
        ],
    )
    def test_other_transports_have_no_reasoning_tier(self, protocol, method):
        """embedding 与 OCR 没有推理语义,给它们加档位只会静默无效(issue #4 同款决策)。"""
        assert "reasoning_effort" not in inspect.signature(getattr(protocol, method)).parameters


class _DummyStatusProvider(_DummyRecorder):
    @property
    def telemetry_status(self) -> TelemetryStatus:
        return TelemetryStatus(
            degraded=False,
            fatal=False,
            reason=None,
            degraded_for_s=None,
            dropped_rows=0,
            retry_after_s=None,
        )


def test_status_provider_is_a_separate_optional_port():
    """状态**不得**并进 TelemetryRecorder: 那会让只实现 record_llm_call 的对象
    当场不再满足 @runtime_checkable 的结构检查(设计 §3.3,Codex 审查)。"""
    assert isinstance(_DummyStatusProvider(), TelemetryStatusProvider)
    assert isinstance(_DummyStatusProvider(), TelemetryRecorder)
    assert not isinstance(_DummyRecorder(), TelemetryStatusProvider)
    assert isinstance(_DummyRecorder(), TelemetryRecorder)  # 这条断言是那条决策的执法点


def _decision(**overrides) -> GateDecision:
    base = {
        "source_name": "qwen_1",
        "allowed": True,
        "state": GateState.CLOSED,
        "epoch": 0,
        "is_probe": False,
        "probe_owner": None,
        "retry_after_s": 0.0,
    }
    base.update(overrides)
    return GateDecision(**base)


class TestGateDecisionInvariants:
    """校验逐条移植 CHS ports.py:405-440。"""

    def test_valid_probe_decision(self):
        d = _decision(state=GateState.HALF_OPEN, is_probe=True, probe_owner="w1")
        assert d.is_probe and d.probe_owner == "w1"

    def test_empty_source_rejected(self):
        with pytest.raises(ValueError):
            _decision(source_name=" ")

    def test_negative_epoch_and_retry_after_rejected(self):
        with pytest.raises(ValueError):
            _decision(epoch=-1)
        with pytest.raises(ValueError):
            _decision(retry_after_s=-0.1)

    def test_open_state_cannot_allow(self):
        with pytest.raises(ValueError):
            _decision(state=GateState.OPEN, allowed=True)

    def test_half_open_admission_must_be_probe(self):
        with pytest.raises(ValueError):
            _decision(state=GateState.HALF_OPEN, is_probe=False)

    def test_probe_requires_owner_and_half_open(self):
        with pytest.raises(ValueError):
            _decision(state=GateState.HALF_OPEN, is_probe=True, probe_owner=None)
        with pytest.raises(ValueError):
            _decision(state=GateState.CLOSED, is_probe=True, probe_owner="w1")

    def test_non_probe_cannot_carry_owner(self):
        with pytest.raises(ValueError):
            _decision(probe_owner="w1")


class TestGateUpdate:
    def test_bounds(self):
        u = GateUpdate(
            applied=True, state=GateState.CLOSED, epoch=0, failure_count=0, retry_after_s=0.0
        )
        assert u.applied
        with pytest.raises(ValueError):
            GateUpdate(
                applied=True, state=GateState.CLOSED, epoch=-1, failure_count=0, retry_after_s=0.0
            )
        with pytest.raises(ValueError):
            GateUpdate(
                applied=True, state=GateState.CLOSED, epoch=0, failure_count=-1, retry_after_s=0.0
            )


class TestTelemetryRecorderSignature:
    """`record_llm_call` 的冻结签名以 `inspect.signature` 实测,不凭记忆断言。

    该 Protocol 的纪律是新增参数**不设默认值**(ports.py docstring):库外无第三方
    实现者,而带默认值的参数会让 emitter 漏传时静默落默认值——遥测里的租户归属
    一旦静默错位,事后无从分辨是"没传"还是"就是空的"。
    """

    def test_caller_dimensions_are_declared(self):
        import inspect

        params = inspect.signature(TelemetryRecorder.record_llm_call).parameters
        assert {"tenant_id", "meta"} <= set(params)

    @pytest.mark.parametrize(
        "name", ["tenant_id", "meta", "thinking_observation", "reasoning_effort"]
    )
    def test_caller_dimensions_have_no_default(self, name):
        import inspect

        param = inspect.signature(TelemetryRecorder.record_llm_call).parameters[name]
        assert param.default is inspect.Parameter.empty
        assert param.kind is inspect.Parameter.KEYWORD_ONLY


class TestOcrPorts:
    """M3 三个 OCR Protocol(设计 §3.2): runtime_checkable 结构判定。"""

    def test_ocr_ports_runtime_checkable(self):
        from polygateway.ports import OcrLayoutPort, OcrTextPort, OcrTransport

        class GoodClient:
            async def recognize_text(self, image): ...
            async def parse_layout(self, image): ...

        class GoodTransport:
            async def recognize_text(self, *, image, source, call_id): ...
            async def parse_layout(self, *, image, source, call_id): ...
            async def check_health(self, *, source): ...

        assert isinstance(GoodClient(), OcrTextPort)
        assert isinstance(GoodClient(), OcrLayoutPort)
        assert isinstance(GoodTransport(), OcrTransport)

    def test_missing_method_rejected(self):
        from polygateway.ports import OcrTransport

        class NoHealth:
            async def recognize_text(self, *, image, source, call_id): ...
            async def parse_layout(self, *, image, source, call_id): ...

        assert not isinstance(NoHealth(), OcrTransport)