openweather: refactored the OpenWeather source files to relocate normalization logic to internal/normalizers.

internal/normalizers/openweather/wmo_map.go

@@ -0,0 +1,98 @@
+// FILE: ./internal/normalizers/openweather/wmo_map.go
+package openweather
+
+import "gitea.maximumdirect.net/ejr/weatherfeeder/internal/model"
+
+// mapOpenWeatherToWMO maps OpenWeather weather condition IDs into weatherfeeder's
+// canonical WMO code vocabulary.
+//
+// This is an approximate semantic mapping between two different code systems.
+// We map conservatively into the subset currently represented in standards.WMODescriptions.
+func mapOpenWeatherToWMO(owmID int) model.WMOCode {
+	switch {
+	// 2xx Thunderstorm
+	case owmID >= 200 && owmID <= 232:
+		return 95
+
+	// 3xx Drizzle
+	case owmID >= 300 && owmID <= 321:
+		if owmID == 300 {
+			return 51
+		}
+		if owmID == 302 {
+			return 55
+		}
+		return 53
+
+	// 5xx Rain
+	case owmID >= 500 && owmID <= 531:
+		// 511 is "freezing rain"
+		if owmID == 511 {
+			return 67
+		}
+
+		// showers bucket (520-531)
+		if owmID >= 520 && owmID <= 531 {
+			if owmID == 520 {
+				return 80
+			}
+			if owmID == 522 {
+				return 82
+			}
+			return 81
+		}
+
+		// normal rain intensity
+		if owmID == 500 {
+			return 61
+		}
+		if owmID == 501 {
+			return 63
+		}
+		if owmID >= 502 && owmID <= 504 {
+			return 65
+		}
+		return 63
+
+	// 6xx Snow
+	case owmID >= 600 && owmID <= 622:
+		if owmID == 600 {
+			return 71
+		}
+		if owmID == 601 {
+			return 73
+		}
+		if owmID == 602 {
+			return 75
+		}
+
+		// Snow showers bucket (620-622)
+		if owmID == 620 {
+			return 85
+		}
+		if owmID == 621 || owmID == 622 {
+			return 86
+		}
+
+		return 73
+
+	// 7xx Atmosphere (mist/smoke/haze/dust/fog/etc.)
+	case owmID >= 701 && owmID <= 781:
+		return 45
+
+	// 800 Clear
+	case owmID == 800:
+		return 0
+
+	// 80x Clouds
+	case owmID == 801:
+		return 1
+	case owmID == 802:
+		return 2
+	case owmID == 803 || owmID == 804:
+		return 3
+
+	default:
+		return model.WMOUnknown
+	}
+}