// forecast_test.go - Unit tests (example)
package main

import (
	"math"
	"testing"
	"time"
)

func TestCalculateFeelsLike(t *testing.T) {
	tests := []struct {
		name      string
		temp      float64
		humidity  float64
		windSpeed float64
		want      float64
	}{
		{"Cold with wind", 5, 80, 10, 0.49},      // Approximate wind chill
		{"Warm with humidity", 30, 80, 5, 32.65}, // Approximate heat index
		{"Moderate", 20, 50, 5, 20},              // No adjustment
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got := CalculateFeelsLike(tt.temp, tt.humidity, tt.windSpeed)
			if math.Abs(got-tt.want) > 1.0 { // Allow 1 degree tolerance
				t.Errorf("CalculateFeelsLike() = %v, want %v", got, tt.want)
			}
		})
	}
}

func TestWeatherMapper(t *testing.T) {
	mapper := NewWeatherMapper()
	sunrise := time.Date(2026, 2, 1, 8, 0, 0, 0, time.UTC)
	sunset := time.Date(2026, 2, 1, 16, 0, 0, 0, time.UTC)

	tests := []struct {
		symbol   int
		time     time.Time
		wantID   int
		wantIcon string
	}{
		{1, sunrise.Add(2 * time.Hour), 800, "01d"}, // Clear, daytime
		{1, sunset.Add(2 * time.Hour), 800, "01n"},  // Clear, nighttime
		{25, sunrise, 500, "10d"},                   // Light rain, daytime
		{91, sunset, 200, "11n"},                    // Thunderstorm, nighttime
	}

	for _, tt := range tests {
		t.Run("", func(t *testing.T) {
			weather := mapper.Map(tt.symbol, tt.time, sunrise, sunset)
			if weather.ID != tt.wantID {
				t.Errorf("Weather.ID = %v, want %v", weather.ID, tt.wantID)
			}
			if weather.Icon != tt.wantIcon {
				t.Errorf("Weather.Icon = %v, want %v", weather.Icon, tt.wantIcon)
			}
		})
	}
}

func TestSunCalculator(t *testing.T) {
	calculator := NewSunCalculator(60.169, 24.935, 2) // Helsinki

	date := time.Date(2026, 2, 1, 0, 0, 0, 0, time.UTC)
	sunrise, sunset, err := calculator.Calculate(date)

	if err != nil {
		t.Errorf("SunCalculator.Calculate() error = %v", err)
	}

	if sunrise.IsZero() || sunset.IsZero() {
		t.Errorf("Sunrise or sunset is zero")
	}

	// Sunrise should be before sunset
	if !sunrise.Before(sunset) {
		t.Errorf("Sunrise %v not before sunset %v", sunrise, sunset)
	}
}