package pricing

import (
	"testing"

	"github.com/stretchr/testify/assert"
)

func TestMMS43Prices(t *testing.T) {
	testCases := []struct {
		name           string
		params         PricingParams
		expectedPrices map[string]Price
		expectedError  bool
	}{
		{
			name: "First trip - should be free for passenger",
			params: PricingParams{
				Beneficiary: BeneficiaryParams{
					History:  0, // First trip
					Priority: false,
				},
				SharedMobility: SharedMobilityParams{
					PassengerDistance: 10000, // 10km in meters
					DriverDistance:    15000, // 15km in meters
				},
			},
			expectedPrices: map[string]Price{
				"passenger": {Amount: 0.0, Currency: "EUR"},   // Free for first trip
				"driver":    {Amount: 4.5, Currency: "EUR"},   // 15km * 0.30€/km
			},
			expectedError: false,
		},
		{
			name: "Second trip - should be free for passenger",
			params: PricingParams{
				Beneficiary: BeneficiaryParams{
					History:  1, // Second trip
					Priority: false,
				},
				SharedMobility: SharedMobilityParams{
					PassengerDistance: 20000, // 20km in meters
					DriverDistance:    25000, // 25km in meters
				},
			},
			expectedPrices: map[string]Price{
				"passenger": {Amount: 0.0, Currency: "EUR"},   // Free for second trip
				"driver":    {Amount: 7.5, Currency: "EUR"},   // 25km * 0.30€/km
			},
			expectedError: false,
		},
		{
			name: "Third trip - passenger should pay",
			params: PricingParams{
				Beneficiary: BeneficiaryParams{
					History:  2, // Third trip
					Priority: false,
				},
				SharedMobility: SharedMobilityParams{
					PassengerDistance: 10000, // 10km in meters
					DriverDistance:    10000, // 10km in meters
				},
			},
			expectedPrices: map[string]Price{
				"passenger": {Amount: 1.5, Currency: "EUR"},   // 10km * 0.15€/km
				"driver":    {Amount: 3.0, Currency: "EUR"},   // 10km * 0.30€/km
			},
			expectedError: false,
		},
		{
			name: "Multiple trips - passenger pays normal rate",
			params: PricingParams{
				Beneficiary: BeneficiaryParams{
					History:  5, // Multiple trips
					Priority: false,
				},
				SharedMobility: SharedMobilityParams{
					PassengerDistance: 30000, // 30km in meters
					DriverDistance:    35000, // 35km in meters
				},
			},
			expectedPrices: map[string]Price{
				"passenger": {Amount: 4.5, Currency: "EUR"},    // 30km * 0.15€/km
				"driver":    {Amount: 10.5, Currency: "EUR"},   // 35km * 0.30€/km
			},
			expectedError: false,
		},
		{
			name: "Zero distance - should return zero amounts",
			params: PricingParams{
				Beneficiary: BeneficiaryParams{
					History:  3,
					Priority: false,
				},
				SharedMobility: SharedMobilityParams{
					PassengerDistance: 0,
					DriverDistance:    0,
				},
			},
			expectedPrices: map[string]Price{
				"passenger": {Amount: 0.0, Currency: "EUR"},
				"driver":    {Amount: 0.0, Currency: "EUR"},
			},
			expectedError: false,
		},
		{
			name: "Large distances - check calculation accuracy",
			params: PricingParams{
				Beneficiary: BeneficiaryParams{
					History:  10,
					Priority: false,
				},
				SharedMobility: SharedMobilityParams{
					PassengerDistance: 100000, // 100km in meters
					DriverDistance:    120000, // 120km in meters
				},
			},
			expectedPrices: map[string]Price{
				"passenger": {Amount: 15.0, Currency: "EUR"},   // 100km * 0.15€/km
				"driver":    {Amount: 36.0, Currency: "EUR"},   // 120km * 0.30€/km
			},
			expectedError: false,
		},
		{
			name: "Edge case - exactly 2 trips history (3rd trip)",
			params: PricingParams{
				Beneficiary: BeneficiaryParams{
					History:  2, // Exactly at the limit
					Priority: false,
				},
				SharedMobility: SharedMobilityParams{
					PassengerDistance: 4000,  // 4km in meters
					DriverDistance:    5000,  // 5km in meters
				},
			},
			expectedPrices: map[string]Price{
				"passenger": {Amount: 0.6, Currency: "EUR"},    // 4km * 0.15€/km (first paid trip)
				"driver":    {Amount: 1.5, Currency: "EUR"},    // 5km * 0.30€/km
			},
			expectedError: false,
		},
		{
			name: "Small distances with fractions",
			params: PricingParams{
				Beneficiary: BeneficiaryParams{
					History:  3,
					Priority: false,
				},
				SharedMobility: SharedMobilityParams{
					PassengerDistance: 2000,  // 2km in meters
					DriverDistance:    3000,  // 3km in meters
				},
			},
			expectedPrices: map[string]Price{
				"passenger": {Amount: 0.3, Currency: "EUR"},    // 2km * 0.15€/km
				"driver":    {Amount: 0.9, Currency: "EUR"},    // 3km * 0.30€/km
			},
			expectedError: false,
		},
	}

	for _, tc := range testCases {
		t.Run(tc.name, func(t *testing.T) {
			pricingService, err := NewMMS43PricingService()
			assert.NoError(t, err)

			prices, err := pricingService.Prices(tc.params)
			if tc.expectedError {
				assert.Error(t, err)
			} else {
				assert.NoError(t, err)
				// Use InDelta for floating-point comparisons to handle precision issues
				assert.InDelta(t, tc.expectedPrices["passenger"].Amount, prices["passenger"].Amount, 0.001)
				assert.Equal(t, tc.expectedPrices["passenger"].Currency, prices["passenger"].Currency)
				assert.InDelta(t, tc.expectedPrices["driver"].Amount, prices["driver"].Amount, 0.001)
				assert.Equal(t, tc.expectedPrices["driver"].Currency, prices["driver"].Currency)
			}
		})
	}
}

func TestMMS43PricingEdgeCases(t *testing.T) {
	pricingService, err := NewMMS43PricingService()
	assert.NoError(t, err)

	t.Run("Negative history should still work", func(t *testing.T) {
		params := PricingParams{
			Beneficiary: BeneficiaryParams{
				History: -1, // Edge case: negative history
			},
			SharedMobility: SharedMobilityParams{
				PassengerDistance: 10000,
				DriverDistance:    10000,
			},
		}

		prices, err := pricingService.Prices(params)
		assert.NoError(t, err)
		// Should still be free (2 - (-1) = 3 > 0)
		assert.InDelta(t, 0.0, prices["passenger"].Amount, 0.001)
		assert.InDelta(t, 3.0, prices["driver"].Amount, 0.001)
	})

	t.Run("Very high history", func(t *testing.T) {
		params := PricingParams{
			Beneficiary: BeneficiaryParams{
				History: 100,
			},
			SharedMobility: SharedMobilityParams{
				PassengerDistance: 10000,
				DriverDistance:    10000,
			},
		}

		prices, err := pricingService.Prices(params)
		assert.NoError(t, err)
		// Should charge normal rate
		assert.InDelta(t, 1.5, prices["passenger"].Amount, 0.001)
		assert.InDelta(t, 3.0, prices["driver"].Amount, 0.001)
	})
}