smart-project-pricing/后端服务/tests/test_services/test_profit_service.py

"""利润模拟服务单元测试

测试 ProfitService 的核心业务逻辑
"""

import pytest
from decimal import Decimal
from unittest.mock import AsyncMock, patch, MagicMock

from sqlalchemy.ext.asyncio import AsyncSession

from app.services.profit_service import ProfitService
from app.schemas.profit import PeriodType
from app.models import PricingPlan, FixedCost


class TestProfitService:
    """利润模拟服务测试类"""
    
    @pytest.mark.unit
    def test_calculate_profit_basic(self):
        """测试基础利润计算"""
        service = ProfitService(None)
        
        revenue, cost, profit, margin = service.calculate_profit(
            price=100.0,
            cost_per_unit=60.0,
            volume=100
        )
        
        assert revenue == 10000.0
        assert cost == 6000.0
        assert profit == 4000.0
        assert margin == 40.0
    
    @pytest.mark.unit
    def test_calculate_profit_zero_revenue(self):
        """测试零收入时的处理"""
        service = ProfitService(None)
        
        revenue, cost, profit, margin = service.calculate_profit(
            price=100.0,
            cost_per_unit=60.0,
            volume=0
        )
        
        assert revenue == 0
        assert cost == 0
        assert profit == 0
        assert margin == 0
    
    @pytest.mark.unit
    def test_calculate_profit_negative(self):
        """测试亏损情况"""
        service = ProfitService(None)
        
        revenue, cost, profit, margin = service.calculate_profit(
            price=50.0,
            cost_per_unit=60.0,
            volume=100
        )
        
        assert revenue == 5000.0
        assert cost == 6000.0
        assert profit == -1000.0
        assert margin == -20.0
    
    @pytest.mark.unit
    def test_calculate_breakeven_basic(self):
        """测试基础盈亏平衡计算"""
        service = ProfitService(None)
        
        breakeven = service.calculate_breakeven(
            price=100.0,
            variable_cost=60.0,
            fixed_cost=0
        )
        
        assert breakeven == 1
    
    @pytest.mark.unit
    def test_calculate_breakeven_with_fixed_cost(self):
        """测试有固定成本的盈亏平衡"""
        service = ProfitService(None)
        
        breakeven = service.calculate_breakeven(
            price=100.0,
            variable_cost=60.0,
            fixed_cost=4000.0
        )
        
        assert breakeven == 101
    
    @pytest.mark.unit
    def test_calculate_breakeven_no_margin(self):
        """测试边际贡献为负时的处理"""
        service = ProfitService(None)
        
        breakeven = service.calculate_breakeven(
            price=50.0,
            variable_cost=60.0,
            fixed_cost=1000.0
        )
        
        assert breakeven == 999999
    
    @pytest.mark.unit
    @pytest.mark.asyncio
    async def test_get_pricing_plan(
        self,
        db_session: AsyncSession,
        sample_pricing_plan: PricingPlan
    ):
        """测试获取定价方案"""
        service = ProfitService(db_session)
        
        plan = await service.get_pricing_plan(sample_pricing_plan.id)
        
        assert plan.id == sample_pricing_plan.id
        assert plan.plan_name == "2026年Q1定价"
    
    @pytest.mark.unit
    @pytest.mark.asyncio
    async def test_get_pricing_plan_not_found(
        self,
        db_session: AsyncSession
    ):
        """测试获取不存在的方案"""
        service = ProfitService(db_session)
        
        with pytest.raises(ValueError, match="定价方案不存在"):
            await service.get_pricing_plan(99999)
    
    @pytest.mark.unit
    @pytest.mark.asyncio
    async def test_get_monthly_fixed_cost(
        self,
        db_session: AsyncSession,
        sample_fixed_cost: FixedCost
    ):
        """测试获取月度固定成本"""
        service = ProfitService(db_session)
        
        total = await service.get_monthly_fixed_cost()
        
        assert total == Decimal("30000.00")
    
    @pytest.mark.unit
    @pytest.mark.asyncio
    async def test_simulate_profit(
        self,
        db_session: AsyncSession,
        sample_pricing_plan: PricingPlan
    ):
        """测试利润模拟"""
        service = ProfitService(db_session)
        
        response = await service.simulate_profit(
            pricing_plan_id=sample_pricing_plan.id,
            price=580.0,
            estimated_volume=100,
            period_type=PeriodType.MONTHLY,
        )
        
        assert response.pricing_plan_id == sample_pricing_plan.id
        assert response.input.price == 580.0
        assert response.input.estimated_volume == 100
    
    @pytest.mark.unit
    @pytest.mark.asyncio
    async def test_sensitivity_analysis(
        self,
        db_session: AsyncSession,
        sample_pricing_plan: PricingPlan
    ):
        """测试敏感性分析"""
        service = ProfitService(db_session)
        
        sim_response = await service.simulate_profit(
            pricing_plan_id=sample_pricing_plan.id,
            price=580.0,
            estimated_volume=100,
            period_type=PeriodType.MONTHLY,
        )
        
        response = await service.sensitivity_analysis(
            simulation_id=sim_response.simulation_id,
            price_change_rates=[-20, -10, 0, 10, 20]
        )
        
        assert response.simulation_id == sim_response.simulation_id
        assert len(response.sensitivity_results) == 5
    
    @pytest.mark.unit
    @pytest.mark.asyncio
    async def test_breakeven_analysis(
        self,
        db_session: AsyncSession,
        sample_pricing_plan: PricingPlan,
        sample_fixed_cost: FixedCost
    ):
        """测试盈亏平衡分析"""
        service = ProfitService(db_session)
        
        response = await service.breakeven_analysis(
            pricing_plan_id=sample_pricing_plan.id
        )
        
        assert response.pricing_plan_id == sample_pricing_plan.id
        assert response.price > 0
        assert response.breakeven_volume > 0