package impact

import (
	"testing"

	"github.com/damirmukimov/city_resource_graph/models/customer"
	"github.com/damirmukimov/city_resource_graph/models/params"
	"github.com/stretchr/testify/assert"
)

func TestCalculateImpact(t *testing.T) {
	tests := []struct {
		name          string
		year          int
		custMetrics   customer.CustomerMetrics
		expectedCO2   float64
		expectedWater float64
		expectedWaste float64
	}{
		{
			name: "Year 1 impact calculation",
			year: 1,
			custMetrics: customer.CustomerMetrics{
				TotalOrgs: 500,
			},
			expectedCO2:   94500.0,   // 500000 * 0.3 * 0.9 * 0.7
			expectedWater: 2500000.0, // 500 * 25000 * 0.20
			expectedWaste: 7500.0,    // 500 * 100 * 0.15
		},
		{
			name: "Year 2 impact calculation",
			year: 2,
			custMetrics: customer.CustomerMetrics{
				TotalOrgs: 2000,
			},
			expectedCO2:   283500.0,   // 1500000 * 0.3 * 0.9 * 0.7
			expectedWater: 12500000.0, // 2000 * 25000 * 0.25
			expectedWaste: 50000.0,    // 2000 * 100 * 0.25
		},
		{
			name: "Year 3 impact calculation",
			year: 3,
			custMetrics: customer.CustomerMetrics{
				TotalOrgs: 5000,
			},
			expectedCO2:   472500.0,   // 2500000 * 0.3 * 0.9 * 0.7 = 472500
			expectedWater: 37500000.0, // 5000 * 25000 * 0.30
			expectedWaste: 175000.0,   // 5000 * 100 * 0.35
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			p := createTestParams(tt.year)

			result := CalculateImpact(tt.year, tt.custMetrics, p)

			assert.InDelta(t, tt.expectedCO2, result.CO2Avoided, 0.01, "CO2 avoided should match")
			assert.InDelta(t, tt.expectedWater, result.WaterReused, 0.01, "Water reused should match")
			assert.InDelta(t, tt.expectedWaste, result.WasteDiverted, 0.01, "Waste diverted should match")
		})
	}
}

func createTestParams(year int) *params.Params {
	yearKey := params.YearKey(year)

	return &params.Params{
		Impact: params.ImpactParams{
			HeatMWh:            params.YearlyFloat{yearKey: float64(500000 + (year-1)*1000000)}, // 500k, 1.5M, 3M
			GridFactor:         0.3,
			HXEff:              0.9,
			Utilization:        0.7,
			WaterPerOrg:        25000.0,
			WaterReuseRate:     params.YearlyFloat{yearKey: 0.20 + float64(year-1)*0.05}, // 0.20, 0.25, 0.30
			WastePerOrg:        100.0,
			WasteDiversionRate: params.YearlyFloat{yearKey: 0.15 + float64(year-1)*0.10}, // 0.15, 0.25, 0.35
		},
	}
}