1 files changed, 138 insertions, 0 deletions
diff --git a/converter.go b/converter.go
new file mode 100644
index 0000000..0e2b74c
--- /dev/null
+++ b/converter.go
@@ -0,0 +1,138 @@
+// converter.go - Converts ForecastData to OWMResponse
+package main
+
+import (
+	"fmt"
+	"math"
+	"time"
+)
+
+// ToOWMResponse converts ForecastData to OWMResponse format
+func (fd *ForecastData) ToOWMResponse(mapper *WeatherMapper) (*OWMResponse, error) {
+	loc, err := time.LoadLocation(fd.Timezone)
+	if err != nil {
+		return nil, fmt.Errorf("loading timezone: %w", err)
+	}
+
+	// Calculate timezone offset
+	firstTime := time.Unix(fd.Timestamps[0], 0).UTC()
+	_, offset := firstTime.In(loc).Zone()
+
+	// Create response
+	response := &OWMResponse{
+		Lat:            fd.Latitude,
+		Lon:            fd.Longitude,
+		Timezone:       fd.Timezone,
+		TimezoneOffset: offset,
+	}
+
+	// Calculate sunrise/sunset for first day
+	sunCalc := NewSunCalculator(fd.Latitude, fd.Longitude, float64(offset)/3600)
+	sunrise, sunset, err := sunCalc.Calculate(firstTime)
+	if err != nil {
+		// Use defaults if calculation fails
+		sunrise = firstTime.Add(8 * time.Hour)
+		sunset = firstTime.Add(16 * time.Hour)
+	}
+
+	// Convert each forecast point
+	hourly := make([]Current, 0, len(fd.Timestamps))
+	for i, timestamp := range fd.Timestamps {
+		current, err := fd.convertToCurrent(i, timestamp, loc, sunrise, sunset, mapper)
+		if err != nil {
+			return nil, fmt.Errorf("converting point %d: %w", i, err)
+		}
+		hourly = append(hourly, current)
+	}
+
+	response.Current = hourly[0]
+	response.Current.Sunrise = sunrise.Unix()
+	response.Current.Sunset = sunset.Unix()
+	response.Hourly = hourly
+
+	return response, nil
+}
+
+func (fd *ForecastData) convertToCurrent(index int, timestamp int64, loc *time.Location, sunrise, sunset time.Time, mapper *WeatherMapper) (Current, error) {
+	current := Current{
+		Dt:  timestamp,
+		Uvi: 0, // Not available from FMI
+	}
+
+	// Add ISO 8601 local time
+	current.LocalTime = time.Unix(timestamp, 0).In(loc).Format(time.RFC3339)
+
+	// Extract temperature
+	if val, err := fd.getFloatValue(index, "Temperature"); err == nil && !math.IsNaN(val) {
+		current.Temp = val
+	}
+
+	// Extract humidity
+	if val, err := fd.getFloatValue(index, "Humidity"); err == nil && !math.IsNaN(val) {
+		current.Humidity = int(math.Round(val))
+	}
+
+	// Extract pressure
+	if val, err := fd.getFloatValue(index, "Pressure"); err == nil && !math.IsNaN(val) {
+		current.Pressure = int(math.Round(val))
+	}
+
+	// Extract dew point
+	if val, err := fd.getFloatValue(index, "dewPoint"); err == nil && !math.IsNaN(val) {
+		current.DewPoint = val
+	}
+
+	// Extract wind speed
+	if val, err := fd.getFloatValue(index, "WindSpeedMS"); err == nil && !math.IsNaN(val) {
+		current.WindSpeed = val
+	}
+
+	// Extract wind direction
+	if val, err := fd.getFloatValue(index, "WindDirection"); err == nil && !math.IsNaN(val) {
+		current.WindDeg = int(math.Round(val))
+	}
+
+	// Extract wind gust
+	if val, err := fd.getFloatValue(index, "WindGust"); err == nil && !math.IsNaN(val) {
+		current.WindGust = val
+	}
+
+	// Extract cloud cover
+	if val, err := fd.getFloatValue(index, "TotalCloudCover"); err == nil && !math.IsNaN(val) {
+		current.Clouds = int(math.Round(val))
+	}
+
+	// Extract visibility
+	if val, err := fd.getFloatValue(index, "visibility"); err == nil && !math.IsNaN(val) {
+		current.Visibility = int(math.Round(val))
+	}
+
+	// Calculate feels-like temperature
+	current.FeelsLike = CalculateFeelsLike(current.Temp, float64(current.Humidity), current.WindSpeed)
+
+	// Handle precipitation
+	if val, err := fd.getFloatValue(index, "PrecipitationRate"); err == nil && !math.IsNaN(val) && val > 0 {
+		current.Rain = &Rain{OneH: val}
+	}
+
+	// Map weather symbol
+	if val, err := fd.getFloatValue(index, "WeatherSymbol3"); err == nil && !math.IsNaN(val) {
+		symbol := int(math.Round(val))
+		forecastTime := time.Unix(timestamp, 0)
+		current.Weather = []Weather{mapper.Map(symbol, forecastTime, sunrise, sunset)}
+	} else {
+		// Default weather
+		current.Weather = []Weather{{800, "Clear", "clear sky", "01d"}}
+	}
+
+	return current, nil
+}
+
+func (fd *ForecastData) getFloatValue(rowIndex int, paramName string) (float64, error) {
+	if paramIndex, ok := fd.ParamIndex[paramName]; ok {
+		if rowIndex < len(fd.Values) && paramIndex < len(fd.Values[rowIndex]) {
+			return fd.Values[rowIndex][paramIndex], nil
+		}
+	}
+	return math.NaN(), fmt.Errorf("parameter %s not found or out of bounds", paramName)
+}