Add SPC provider parsing helpers

internal/providers/spc/product.go

@@ -0,0 +1,89 @@
+package spc
+
+import "fmt"
+
+const (
+	OutlookTypeCategorical = "categorical"
+	OutlookTypeTornado     = "tornado"
+	OutlookTypeHail        = "hail"
+	OutlookTypeWind        = "wind"
+)
+
+// GeoJSONProduct describes one required SPC convective outlook GeoJSON product.
+type GeoJSONProduct struct {
+	Key         string
+	Day         int
+	OutlookType string
+	URL         string
+}
+
+// DiscussionProduct describes one required SPC convective outlook print page.
+type DiscussionProduct struct {
+	Key string
+	Day int
+	URL string
+}
+
+var geoJSONProducts = []GeoJSONProduct{
+	{Key: "day1_categorical", Day: 1, OutlookType: OutlookTypeCategorical, URL: "https://www.spc.noaa.gov/products/outlook/day1otlk_cat.nolyr.geojson"},
+	{Key: "day1_tornado", Day: 1, OutlookType: OutlookTypeTornado, URL: "https://www.spc.noaa.gov/products/outlook/day1otlk_torn.nolyr.geojson"},
+	{Key: "day1_hail", Day: 1, OutlookType: OutlookTypeHail, URL: "https://www.spc.noaa.gov/products/outlook/day1otlk_hail.nolyr.geojson"},
+	{Key: "day1_wind", Day: 1, OutlookType: OutlookTypeWind, URL: "https://www.spc.noaa.gov/products/outlook/day1otlk_wind.nolyr.geojson"},
+	{Key: "day2_categorical", Day: 2, OutlookType: OutlookTypeCategorical, URL: "https://www.spc.noaa.gov/products/outlook/day2otlk_cat.nolyr.geojson"},
+	{Key: "day2_tornado", Day: 2, OutlookType: OutlookTypeTornado, URL: "https://www.spc.noaa.gov/products/outlook/day2otlk_torn.nolyr.geojson"},
+	{Key: "day2_hail", Day: 2, OutlookType: OutlookTypeHail, URL: "https://www.spc.noaa.gov/products/outlook/day2otlk_hail.nolyr.geojson"},
+	{Key: "day2_wind", Day: 2, OutlookType: OutlookTypeWind, URL: "https://www.spc.noaa.gov/products/outlook/day2otlk_wind.nolyr.geojson"},
+	{Key: "day3_categorical", Day: 3, OutlookType: OutlookTypeCategorical, URL: "https://www.spc.noaa.gov/products/outlook/day3otlk_cat.nolyr.geojson"},
+	{Key: "day3_tornado", Day: 3, OutlookType: OutlookTypeTornado, URL: "https://www.spc.noaa.gov/products/outlook/day3otlk_torn.nolyr.geojson"},
+	{Key: "day3_hail", Day: 3, OutlookType: OutlookTypeHail, URL: "https://www.spc.noaa.gov/products/outlook/day3otlk_hail.nolyr.geojson"},
+	{Key: "day3_wind", Day: 3, OutlookType: OutlookTypeWind, URL: "https://www.spc.noaa.gov/products/outlook/day3otlk_wind.nolyr.geojson"},
+}
+
+var discussionProducts = []DiscussionProduct{
+	{Key: "day1", Day: 1, URL: "https://www.spc.noaa.gov/products/outlook/day1otlk_prt.html"},
+	{Key: "day2", Day: 2, URL: "https://www.spc.noaa.gov/products/outlook/day2otlk_prt.html"},
+	{Key: "day3", Day: 3, URL: "https://www.spc.noaa.gov/products/outlook/day3otlk_prt.html"},
+}
+
+// GeoJSONProducts returns the required SPC convective outlook GeoJSON products
+// in stable day/type order.
+func GeoJSONProducts() []GeoJSONProduct {
+	out := make([]GeoJSONProduct, len(geoJSONProducts))
+	copy(out, geoJSONProducts)
+	return out
+}
+
+// DiscussionProducts returns the required SPC convective outlook print pages in
+// stable day order.
+func DiscussionProducts() []DiscussionProduct {
+	out := make([]DiscussionProduct, len(discussionProducts))
+	copy(out, discussionProducts)
+	return out
+}
+
+// GeoJSONProductByKey returns product metadata for a configured product key.
+func GeoJSONProductByKey(key string) (GeoJSONProduct, bool) {
+	for _, product := range geoJSONProducts {
+		if product.Key == key {
+			return product, true
+		}
+	}
+	return GeoJSONProduct{}, false
+}
+
+// DiscussionProductByKey returns discussion metadata for a configured day key.
+func DiscussionProductByKey(key string) (DiscussionProduct, bool) {
+	for _, product := range discussionProducts {
+		if product.Key == key {
+			return product, true
+		}
+	}
+	return DiscussionProduct{}, false
+}
+
+func validateProductDay(day int) error {
+	if day < 1 || day > 3 {
+		return fmt.Errorf("day must be 1, 2, or 3, got %d", day)
+	}
+	return nil
+}