map layer management

lib/backgroundLayers.ts

@@ -0,0 +1,27 @@
+export const BACKGROUND_LAYER_OPTIONS = [
+    { id: "raster-base-layer", label: "Raster" },
+    { id: "graticules-line", label: "Graticules" },
+    { id: "land", label: "Land" },
+    { id: "bg-countries-fill", label: "Countries" },
+    { id: "bg-country-borders-line", label: "Country Borders" },
+    { id: "regions-line", label: "Regions" },
+    { id: "lakes-fill", label: "Lakes" },
+    { id: "rivers-line", label: "Rivers" },
+    { id: "geolines-line", label: "Geolines" },
+] as const;
+
+export type BackgroundLayerId = (typeof BACKGROUND_LAYER_OPTIONS)[number]["id"];
+export type BackgroundLayerVisibility = Record<BackgroundLayerId, boolean>;
+
+function buildBackgroundLayerVisibility(value: boolean): BackgroundLayerVisibility {
+    return BACKGROUND_LAYER_OPTIONS.reduce((acc, option) => {
+        acc[option.id] = value;
+        return acc;
+    }, {} as BackgroundLayerVisibility);
+}
+
+export const DEFAULT_BACKGROUND_LAYER_VISIBILITY =
+    buildBackgroundLayerVisibility(true);
+
+export const HIDDEN_BACKGROUND_LAYER_VISIBILITY =
+    buildBackgroundLayerVisibility(false);