"""测试极简基线预测:不调用 LLM,基于主客场场均进球估计,写入 prediction 表。

运行(需先 pip-sync requirements-dev.txt):
  pytest tests/test_baseline.py -v
"""
from __future__ import annotations

from types import SimpleNamespace
from unittest.mock import patch

import pytest

from src.llm.baseline import _avg_goals, predict_baseline


class _FakeUoW:
    """P3-2:baseline 在服务层落库,测试需 mock get_uow。"""

    async def __aenter__(self):
        return SimpleNamespace(
            execute=lambda *a, **k: SimpleNamespace(scalar_one_or_none=lambda: None),
            add=lambda *a, **k: None,
            flush=lambda *a, **k: None,
        )

    async def __aexit__(self, *a):
        return None


async def _fake_upsert(session, **kw):
    return SimpleNamespace(id=1)


@pytest.mark.asyncio
async def test_avg_goals_no_data_returns_zero():
    """无历史数据时场均进球为 0(不抛异常)。"""
    class FakeRow:
        avg_goals = None
        cnt = 0

    class FakeResult:
        def one(self):
            return FakeRow()

    class FakeSession:
        async def execute(self, stmt):
            return FakeResult()

    avg = await _avg_goals(FakeSession(), team_id=1, side="home", league_id=1, before=None)
    assert avg == 0.0


@pytest.mark.asyncio
async def test_avg_goals_with_data():
    """有数据时返回正确均值。"""
    class FakeRow:
        avg_goals = 1.5
        cnt = 10

    class FakeResult:
        def one(self):
            return FakeRow()

    class FakeSession:
        async def execute(self, stmt):
            return FakeResult()

    avg = await _avg_goals(FakeSession(), team_id=1, side="home", league_id=1, before=None)
    assert avg == 1.5


@pytest.mark.asyncio
async def test_predict_baseline_no_llm():
    """基线预测不调用 LLM(provider=model=baseline),latency_ms=0。"""
    captured = {}

    async def fake_avg(db, *, team_id, side, league_id, before):
        captured[f"{side}_{team_id}"] = True
        return 2.4 if side == "home" else 1.6

    class FakeMatch:
        id = 1
        match_id = 1
        home_team_id = 10
        away_team_id = 20
        league_id = 1
        match_status = "scheduled"

    with patch("src.llm.baseline._avg_goals", fake_avg), \
         patch("src.llm.baseline.AsyncSessionLocal") as SLC, \
         patch("src.db.unit_of_work.get_uow", _FakeUoW), \
         patch("src.llm.baseline._insert_or_find_by_fingerprint", _fake_upsert):
        class FakeSession:
            async def get(self, cls, mid):
                return FakeMatch()
        class FakeCM:
            async def __aenter__(self):
                return FakeSession()
            async def __aexit__(self, *a):
                return None
        SLC.return_value = FakeCM()

        result = await predict_baseline(1)

    assert result.provider == "baseline"
    assert result.model == "baseline"
    assert result.mode == "baseline"
    assert result.latency_ms == 0
    assert result.prompt_tokens == 0
    assert result.completion_tokens == 0
    # 2.4 → round = 2, 1.6 → round = 2 → 平局 X
    assert result.pred_home_goals == 2.0
    assert result.pred_away_goals == 2.0
    assert result.pred_1x2 == "X"
    assert result.subjective_confidence == 0.5
    assert "非投注建议" in result.reasoning
    # P3-2:服务层落库,回填真实 prediction_id
    assert result.prediction_id == 1
    # 确认未调用任何 LLM 相关模块
    assert "home_10" in captured and "away_20" in captured


@pytest.mark.asyncio
async def test_predict_baseline_clamps_to_range():
    """预测进球数裁剪到 [0, 10]。"""
    async def fake_avg(db, *, team_id, side, league_id, before):
        return 15.0 if side == "home" else -3.0

    class FakeMatch:
        id = 2
        match_id = 2
        home_team_id = 10
        away_team_id = 20
        league_id = 1
        match_status = "scheduled"

    with patch("src.llm.baseline._avg_goals", fake_avg), \
         patch("src.llm.baseline.AsyncSessionLocal") as SLC, \
         patch("src.db.unit_of_work.get_uow", _FakeUoW), \
         patch("src.llm.baseline._insert_or_find_by_fingerprint", _fake_upsert):
        class FakeSession:
            async def get(self, cls, mid):
                return FakeMatch()
        class FakeCM:
            async def __aenter__(self):
                return FakeSession()
            async def __aexit__(self, *a):
                return None
        SLC.return_value = FakeCM()

        result = await predict_baseline(2)

    assert result.pred_home_goals == 10.0  # clamped
    assert result.pred_away_goals == 0.0   # clamped
    assert result.pred_1x2 == "1"         # 10:0 主胜
    # P3-2:服务层落库,回填真实 prediction_id
    assert result.prediction_id == 1