1 files changed, 63 insertions, 0 deletions
diff --git a/weather_mapper.go b/weather_mapper.go
new file mode 100644
index 0000000..7f01217
--- /dev/null
+++ b/weather_mapper.go
@@ -0,0 +1,63 @@
+// weather_mapper.go - Maps FMI weather symbols to OWM format
+package main
+
+import "time"
+
+// WeatherMapper handles weather symbol mapping
+type WeatherMapper struct {
+	symbolMap map[int]Weather
+}
+
+// NewWeatherMapper creates a new weather mapper
+func NewWeatherMapper() *WeatherMapper {
+	return &WeatherMapper{
+		symbolMap: map[int]Weather{
+			1:  {800, "Clear", "clear sky", "01"},
+			2:  {801, "Clouds", "few clouds", "02"},
+			3:  {802, "Clouds", "scattered clouds", "03"},
+			4:  {803, "Clouds", "broken clouds", "04"},
+			5:  {804, "Clouds", "overcast clouds", "04"},
+			6:  {701, "Mist", "mist", "50"},
+			7:  {701, "Mist", "mist", "50"},
+			8:  {741, "Fog", "fog", "50"},
+			9:  {741, "Fog", "fog", "50"},
+			10: {741, "Fog", "fog", "50"},
+			11: {300, "Drizzle", "light intensity drizzle", "09"},
+			12: {301, "Drizzle", "drizzle", "09"},
+			13: {302, "Drizzle", "heavy intensity drizzle", "09"},
+			21: {520, "Rain", "light intensity shower rain", "09"},
+			22: {521, "Rain", "shower rain", "09"},
+			23: {522, "Rain", "heavy intensity shower rain", "09"},
+			24: {511, "Rain", "freezing rain", "13"},
+			25: {500, "Rain", "light rain", "10"},
+			26: {501, "Rain", "moderate rain", "10"},
+			27: {502, "Rain", "heavy intensity rain", "10"},
+			30: {500, "Rain", "light rain", "10"},
+			31: {501, "Rain", "moderate rain", "10"},
+			32: {502, "Rain", "heavy intensity rain", "10"},
+			40: {600, "Snow", "light snow", "13"},
+			41: {600, "Snow", "light snow", "13"},
+			42: {601, "Snow", "snow", "13"},
+			43: {602, "Snow", "heavy snow", "13"},
+			91: {200, "Thunderstorm", "thunderstorm with light rain", "11"},
+		},
+	}
+}
+
+// Map converts FMI weather symbol to OWM weather with day/night icon
+func (wm *WeatherMapper) Map(symbol int, forecastTime, sunrise, sunset time.Time) Weather {
+	weather, ok := wm.symbolMap[symbol]
+	if !ok {
+		weather = Weather{800, "Clear", "clear sky", "01"}
+	}
+
+	// Determine day/night
+	isDay := forecastTime.After(sunrise) && forecastTime.Before(sunset)
+	if isDay {
+		weather.Icon += "d"
+	} else {
+		weather.Icon += "n"
+	}
+
+	return weather
+}