"""公共配置 + 回测组合 API 测试（TestClient + 内存 SQLite）。

覆盖：
- /api/config GET 返回默认值、PUT 持久化；
- /api/combos CRUD（name 唯一、原地更新保留 created_at、删除）；
- /api/combos/{id}/run 在策略缺失时提前 400（不等到后台才失败）。
"""

from __future__ import annotations

import pytest
from app.api import deps
from app.infrastructure.persistence.sqlalchemy.base import Base
from app.main import app
from fastapi.testclient import TestClient
from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker


@pytest.fixture()
def client(tmp_path) -> TestClient:
    engine = create_engine(f"sqlite:///{tmp_path / 'combo_api.db'}", future=True)
    Base.metadata.create_all(engine)
    Session = sessionmaker(bind=engine, expire_on_commit=False)

    def _session_override():
        with Session() as s:
            yield s

    app.dependency_overrides[deps.get_session] = _session_override
    with TestClient(app) as c:
        yield c
    app.dependency_overrides.clear()


class TestConfigApi:
    def test_get_returns_defaults(self, client: TestClient) -> None:
        cfg = client.get("/api/config").json()
        assert cfg["id"] == "default"
        assert cfg["price_adjustment"] == "hfq"
        assert cfg["min_commission"] == 5.0

    def test_put_persists(self, client: TestClient) -> None:
        body = {
            "commission_rate": 0.00025, "stamp_tax_rate": 0.0005,
            "slippage_rate": 0.0008, "min_commission": 3.0,
            "price_adjustment": "qfq", "benchmark": "000905.SH",
        }
        resp = client.put("/api/config", json=body)
        assert resp.status_code == 200
        got = client.get("/api/config").json()
        assert got["commission_rate"] == pytest.approx(0.00025)
        assert got["price_adjustment"] == "qfq"
        assert got["benchmark"] == "000905.SH"

    def test_put_rejects_unknown_field(self, client: TestClient) -> None:
        """拼错键名必须报错：否则「以为改了滑点、其实没生效」是静默降级。"""
        resp = client.put("/api/config", json={"slippage": 0.001})
        assert resp.status_code == 422
        assert "slippage" in resp.text
        # 值未被改动（仍是默认滑点）
        assert client.get("/api/config").json()["slippage_rate"] == pytest.approx(0.001)


class TestCombosApi:
    def _make_strategy(self, client: TestClient, name: str) -> str:
        resp = client.post(
            "/api/strategies",
            json={"name": name, "factors": [{"name": "dividend_yield", "weight": 1}]},
        )
        assert resp.status_code == 200
        return resp.json()["id"]

    def test_crud(self, client: TestClient) -> None:
        sid = self._make_strategy(client, "高股息")
        body = {
            "name": "组合A", "strategy_ids": [sid],
            "initial_capital": 500000, "hold_count": 10,
            "hold_min_days": 5, "hold_max_days": 30,
            "rebalance_freq": "weekly", "period": ["2024-01-01", "2024-06-01"],
        }
        created = client.post("/api/combos", json=body)
        assert created.status_code == 200
        cid = created.json()["id"]
        assert cid.startswith("CMB-")
        assert created.json()["hold_max_days"] == 30

        assert len(client.get("/api/combos").json()) == 1
        detail = client.get(f"/api/combos/{cid}").json()
        assert detail["strategy_ids"] == [sid]
        assert detail["rebalance_freq"] == "weekly"

        # 原地更新保留 id 与 created_at
        created_at = detail["created_at"]
        upd = client.put(f"/api/combos/{cid}", json={**body, "name": "组合A", "hold_count": 15})
        assert upd.status_code == 200
        assert upd.json()["id"] == cid
        assert upd.json()["created_at"] == created_at
        assert upd.json()["hold_count"] == 15

        assert client.delete(f"/api/combos/{cid}").status_code == 200
        assert client.get(f"/api/combos/{cid}").status_code == 404

    def test_duplicate_name_400(self, client: TestClient) -> None:
        sid = self._make_strategy(client, "S")
        body = {"name": "重名", "strategy_ids": [sid], "hold_count": 5,
                "rebalance_freq": "monthly", "period": ["2024-01-01", "2024-02-01"]}
        assert client.post("/api/combos", json=body).status_code == 200
        assert client.post("/api/combos", json=body).status_code == 400

    def test_run_missing_strategy_400(self, client: TestClient) -> None:
        """引用不存在的策略 → 提交时即 400，而非等后台 Job 才失败。"""
        body = {"name": "缺策略组合", "strategy_ids": ["STG-NOT-EXIST"], "hold_count": 5,
                "rebalance_freq": "monthly", "period": ["2024-01-01", "2024-02-01"]}
        resp = client.post("/api/combos/run", json=body)
        assert resp.status_code == 400
        assert "不存在" in resp.json()["detail"]

    def test_unknown_param_rejected(self, client: TestClient) -> None:
        """回测参数写错键名（capital/hold_days）→ 422，而不是静默用默认值。"""
        sid = self._make_strategy(client, "S2")
        body = {
            "name": "拼错参数", "strategy_ids": [sid], "hold_count": 5,
            "rebalance_freq": "monthly", "period": ["2024-01-01", "2024-02-01"],
            "capital": 500000, "hold_days": 30,
        }
        resp = client.post("/api/combos", json=body)
        assert resp.status_code == 422
        assert "capital" in resp.text and "hold_days" in resp.text
        assert client.get("/api/combos").json() == []