"""OpenAI 错误分类的逐条测试。

`errors.py` 顶部标了「映射未经官方文档证实」——正因为它是推断出来的，才更要把
每条分支钉住：日后拿到真实错误数据来校正时，改动的影响面一眼可见。
"""

from __future__ import annotations

import pytest

from app.domain.generation import Retry, UserFacing
from app.providers.openai.errors import classify


class TestHighConfidenceOverrides:
    """文档没给错误码表，故只对少数语义明确的取值加细。"""

    @pytest.mark.parametrize("field", ["code", "type"])
    def test_insufficient_quota_is_not_worth_retrying(self, field):
        failure = classify(429, **{f"error_{field}": "insufficient_quota"})
        assert failure.retry is Retry.QUOTA
        assert failure.user_facing is UserFacing.QUOTA_EXHAUSTED

    @pytest.mark.parametrize("field", ["code", "type"])
    def test_rate_limit_backs_off(self, field):
        failure = classify(429, **{f"error_{field}": "rate_limit_exceeded"})
        assert failure.retry is Retry.BACKOFF
        assert failure.user_facing is UserFacing.RATE_LIMITED

    @pytest.mark.parametrize("code", ["moderation_blocked", "content_policy_violation"])
    def test_content_rejection_is_terminal(self, code):
        # 同样的输入必然同样被拒——重试只是白花一次配额。
        failure = classify(400, error_code=code)
        assert failure.retry is Retry.NEVER
        assert failure.user_facing is UserFacing.CONTENT_REJECTED

    def test_invalid_key_is_our_problem_not_the_users(self):
        failure = classify(401, error_code="invalid_api_key")
        assert failure.retry is Retry.NEVER
        # 用户看到的是「服务端错误」，不是「你的内容有问题」。
        assert failure.user_facing is UserFacing.SERVER_ERROR

    def test_code_wins_over_type_when_both_are_present(self):
        # code 比 type 更具体，故优先。
        failure = classify(
            429, error_type="rate_limit_exceeded", error_code="insufficient_quota"
        )
        assert failure.retry is Retry.QUOTA


class TestStatusCodeFallback:
    """拿不到 type/code 时只靠状态码——这是本模块的主依据。"""

    def test_429_without_any_hint_is_treated_as_rate_limiting(self):
        """429 两义兼有；猜成配额耗尽会把一次可重试的限流判死，代价更大。"""
        failure = classify(429)
        assert failure.retry is Retry.BACKOFF
        assert failure.user_facing is UserFacing.RATE_LIMITED

    def test_400_without_any_hint_does_not_blame_the_prompt(self):
        """400 同时用于参数错与内容被拒。

        错报「内容被拒」会让用户去改一个其实没问题的提示词，故归服务端错误。
        """
        failure = classify(400)
        assert failure.retry is Retry.NEVER
        assert failure.user_facing is UserFacing.SERVER_ERROR

    @pytest.mark.parametrize("status", [401, 403])
    def test_auth_failures_are_terminal(self, status):
        assert classify(status).retry is Retry.NEVER

    @pytest.mark.parametrize("status", [404, 409, 422])
    def test_other_4xx_are_terminal(self, status):
        assert classify(status).retry is Retry.NEVER

    @pytest.mark.parametrize("status", [500, 502, 503, 504])
    def test_5xx_is_retryable(self, status):
        failure = classify(status)
        assert failure.retry is Retry.BACKOFF
        assert failure.user_facing is UserFacing.UPSTREAM_UNAVAILABLE

    def test_network_failure_is_retryable(self):
        # http_status=None 表示连都没连上。
        failure = classify(None, message="connect timeout")
        assert failure.retry is Retry.BACKOFF
        assert failure.user_facing is UserFacing.UPSTREAM_UNAVAILABLE

    def test_an_unknown_status_leans_towards_retrying(self):
        """未知一律偏可重试：把可恢复的抖动判死是更糟的错误。

        重试预算本身有上限（max_attempts），所以偏向重试是有界的。
        """
        assert classify(599).retry is Retry.BACKOFF


class TestProviderCodeIsNeverEmpty:
    """它是排查时的第一线索，空字符串等于把线索丢了。"""

    def test_code_is_preferred(self):
        assert classify(400, error_type="t", error_code="c").provider_code == "c"

    def test_type_is_used_when_code_is_absent(self):
        assert classify(400, error_type="t").provider_code == "t"

    def test_status_label_is_the_last_resort(self):
        assert classify(503).provider_code == "HTTP_503"

    def test_network_failures_get_a_named_label_too(self):
        assert classify(None).provider_code == "NETWORK_ERROR"


class TestMessageIsCarriedThrough:
    def test_message_is_kept(self):
        assert classify(400, message="bad size").message == "bad size"

    def test_missing_message_becomes_empty_not_none(self):
        # 契约里 message 是字符串；None 会在序列化处变成 null 而非 ""。
        assert classify(400).message == ""