"""预测模拟模块测试 — CVP/投资决策/敏感性/情景/现金流/实物期权/增长质量

覆盖 predict.py 主要端点（纯计算 + 少量DB）：
cvp / investment / sensitivity / scenario / cvp-detailed / cash-forecast /
cash-forecast/history / accuracy / scenario-suggestions /
scenario-suggestion/generate / real-option / growth-quality
"""
import pytest
from fastapi.testclient import TestClient
from sqlalchemy.orm import Session

from app.models import CashForecast, ForecastAccuracy
from tests.conftest import create_test_user, get_token_for_user, auth_header

BASE = "/api/cma/predict"


class TestCvp:
    def test_cvp_basic(self, client: TestClient, db: Session):
        """本量利分析"""
        resp = client.post(f"{BASE}/cvp", json={
            "unit_price": 100, "unit_variable_cost": 60, "fixed_cost": 100000,
        })
        assert resp.status_code == 200
        data = resp.json()
        assert data["contribution_margin"] == 40
        assert data["bep_units"] == 2500  # 100000/40
        assert data["bep_revenue"] == 250000.0

    def test_cvp_with_target_profit(self, client: TestClient, db: Session):
        """含目标利润"""
        resp = client.post(f"{BASE}/cvp", json={
            "unit_price": 100, "unit_variable_cost": 60, "fixed_cost": 100000,
            "target_profit": 20000,
        })
        assert resp.status_code == 200
        # 目标销量 = (100000+20000)/40 = 3000
        assert resp.json()["target_units"] == 3000

    def test_cvp_bad_input(self, client: TestClient, db: Session):
        """非法输入 → 400"""
        resp = client.post(f"{BASE}/cvp", json={"unit_price": "abc"})
        assert resp.status_code == 400


class TestInvestment:
    def test_investment_npv_irr(self, client: TestClient, db: Session):
        """NPV/IRR计算"""
        resp = client.post(f"{BASE}/investment", json={
            "initial_investment": 10000,
            "discount_rate": 10,
            "cash_flows": [3000, 3000, 3000, 3000, 3000],
        })
        assert resp.status_code == 200
        data = resp.json()
        assert "npv_analysis" in data
        assert "irr_analysis" in data

    def test_investment_empty_cashflows(self, client: TestClient, db: Session):
        """空现金流 → 400"""
        resp = client.post(f"{BASE}/investment", json={"initial_investment": 100})
        assert resp.status_code == 400


class TestSensitivityScenario:
    def test_sensitivity(self, client: TestClient, db: Session):
        """敏感性分析"""
        resp = client.post(f"{BASE}/sensitivity", json={
            "base_revenue": 1000, "base_cost": 700,
        })
        assert resp.status_code == 200
        data = resp.json()
        assert data["base_profit"] == 300.0
        assert len(data["factors"]) > 0
        assert "revenue_sensitivity" in data["factors"][0]

    def test_scenario(self, client: TestClient, db: Session):
        """情景模拟"""
        resp = client.post(f"{BASE}/scenario", json={
            "optimistic": {"revenue": 120, "cost": 60},
            "pessimistic": {"revenue": 80, "cost": 70},
            "base": {"revenue": 100, "cost": 65},
        })
        assert resp.status_code == 200
        data = resp.json()
        scenarios = {s["scenario"] for s in data["scenarios"]}
        assert scenarios == {"乐观", "中性", "悲观"}

    def test_scenario_missing(self, client: TestClient, db: Session):
        """缺情景 → 400"""
        resp = client.post(f"{BASE}/scenario", json={"base": {"revenue": 100}})
        assert resp.status_code == 400

    def test_cvp_detailed(self, client: TestClient, db: Session):
        """CVP详细分析（含保本图/方案推演）"""
        resp = client.post(f"{BASE}/cvp-detailed", json={
            "fixed_cost": 617, "variable_cost_rate": 0.4862,
            "unit_price": 228, "current_volume": 5300,
        })
        assert resp.status_code == 200
        data = resp.json()
        assert data["contribution_margin_rate"] == 51.38
        assert len(data["scenarios"]) == 3
        assert len(data["chart_data"]) > 0
        assert data["breakeven_units"] > 0


class TestCashForecast:
    def test_cash_forecast_no_data(self, client: TestClient, db: Session):
        """无历史KPI时仍返回预测（退化处理）"""
        resp = client.post(f"{BASE}/cash-forecast", json={
            "entity_id": 1, "days": 10, "current_cash": 50.0,
        })
        assert resp.status_code == 200
        data = resp.json()
        assert "daily" in data or "forecast" in data or "days" in data

    def test_cash_forecast_history_empty(self, client: TestClient, db: Session):
        """历史为空"""
        create_test_user(db)
        token = get_token_for_user(client)
        resp = client.get(f"{BASE}/cash-forecast/history", headers=auth_header(token))
        assert resp.status_code == 200
        assert resp.json()["data"] == []

    def test_accuracy_empty(self, client: TestClient, db: Session):
        """准确率为空"""
        create_test_user(db)
        token = get_token_for_user(client)
        resp = client.get(f"{BASE}/accuracy", headers=auth_header(token))
        assert resp.status_code == 200
        data = resp.json()
        assert data["data"] == []
        assert data["summary"]["total_periods"] == 0


class TestScenarioSuggestions:
    def test_suggestions_all(self, client: TestClient, db: Session):
        """获取全部情景建议"""
        resp = client.get(f"{BASE}/scenario-suggestions")
        assert resp.status_code == 200
        types = {s["alert_type"] for s in resp.json()["data"]}
        assert types == {"cash_low", "cash_critical", "cost_high", "revenue_drop"}

    def test_suggestions_filter(self, client: TestClient, db: Session):
        """按类型过滤"""
        resp = client.get(f"{BASE}/scenario-suggestions?alert_type=cash_low")
        assert resp.status_code == 200
        data = resp.json()["data"]
        assert len(data) == 1
        assert data[0]["alert_type"] == "cash_low"

    def test_generate_suggestion(self, client: TestClient, db: Session):
        """动态生成建议"""
        resp = client.post(f"{BASE}/scenario-suggestion/generate", json={
            "alert_type": "cost_high", "kpi_name": "销售费用率",
        })
        assert resp.status_code == 200
        assert "title" in resp.json() or "description" in resp.json()


class TestRealOption:
    def test_bs_call_expansion(self, client: TestClient, db: Session):
        """BSM看涨（扩张期权）"""
        resp = client.post(f"{BASE}/real-option", json={
            "opt_type": "expansion", "model": "bs",
            "S0": 100, "X": 80, "t": 3, "r": 0.0174, "sigma": 0.30,
        })
        assert resp.status_code == 200
        data = resp.json()
        assert data["option_value"] > 0
        assert "intermediate" in data
        assert "sensitivity" in data

    def test_bs_put_abandon(self, client: TestClient, db: Session):
        """BSM看跌（放弃期权）"""
        resp = client.post(f"{BASE}/real-option", json={
            "opt_type": "abandon", "model": "bs",
            "S0": 100, "X": 120, "t": 2, "r": 0.05, "sigma": 0.40,
        })
        assert resp.status_code == 200
        assert resp.json()["option_value"] >= 0

    def test_binomial_delay(self, client: TestClient, db: Session):
        """二叉树（延迟期权）"""
        resp = client.post(f"{BASE}/real-option", json={
            "opt_type": "delay", "model": "binomial",
            "S0": 100, "X": 80, "t": 3, "r": 0.05, "sigma": 0.30, "n_steps": 50,
        })
        assert resp.status_code == 200
        assert resp.json()["option_value"] > 0

    def test_binomial_american_put(self, client: TestClient, db: Session):
        """二叉树美式看跌（放弃期权）"""
        resp = client.post(f"{BASE}/real-option", json={
            "opt_type": "abandon", "model": "binomial",
            "S0": 100, "X": 120, "t": 2, "r": 0.05, "sigma": 0.40, "n_steps": 30,
        })
        assert resp.status_code == 200
        assert resp.json()["option_value"] >= 0

    def test_real_option_invalid_params(self, client: TestClient, db: Session):
        """非法参数 → 400"""
        resp = client.post(f"{BASE}/real-option", json={"S0": -5})
        assert resp.status_code == 400

    def test_real_option_unsupported_comb(self, client: TestClient, db: Session):
        """不支持的组合 → 400"""
        resp = client.post(f"{BASE}/real-option", json={"opt_type": "weird", "model": "bs"})
        assert resp.status_code == 400


class TestGrowthQuality:
    def test_growth_quality_entity1(self, client: TestClient, db: Session):
        """酣客增长质量"""
        resp = client.post(f"{BASE}/growth-quality", json={"entity_id": 1})
        assert resp.status_code == 200
        data = resp.json()
        assert "overall" in data or "level" in data or "score" in data

    def test_growth_quality_entity2(self, client: TestClient, db: Session):
        """博海增长质量"""
        resp = client.post(f"{BASE}/growth-quality", json={"entity_id": 2})
        assert resp.status_code == 200
        data = resp.json()
        assert data["entity_name"] == "陕西博海网络科技"

    def test_growth_quality_custom(self, client: TestClient, db: Session):
        """自定义企业数据（低分场景）"""
        resp = client.post(f"{BASE}/growth-quality", json={
            "entity_id": 99,
            "name": "测试企业",
            "rebateRate": 90, "trueGrossMargin": 5, "cashRatio": 3,
            "expenseGrowthRate": 3, "revenueGrowthRate": 1, "mgmtRatio": 500,
        })
        assert resp.status_code == 200
        data = resp.json()
        assert data["entity_name"] == "测试企业"
        assert data["overall"] < 2
        assert data["level_type"] == "danger"
        # 低分诊断
        assert "越增长越重" in data["diagnosis"]