propose model refactoring

src/shared/base-endpoint.ts

@@ -0,0 +1,6 @@
+import type { BaseLayerCore, BaseLayerExtended } from './base-layer.js';
+
+export interface BaseEndpoint {
+  getLayers(): BaseLayerCore[];
+  getLayerById(id: string): BaseLayerCore | null;
+}

src/shared/base-layer.ts

@@ -0,0 +1,61 @@
+import type { BoundingBox, MetadataURL } from './models.js';
+
+/**
+ * Core properties common to all layer types.
+ * This is the minimal contract that all layers must satisfy.
+ */
+export interface BaseLayerCore {
+  /**
+   * Unique identifier within the service.
+   * Maps to:
+   * - `name` for WMS, WFS, WMTS
+   * - `id` for OGC API, STAC
+   * - `title` for TMS (which lacks a separate ID)
+   */
+  id: string;
+
+  /**
+   * Human-readable title for the layer.
+   */
+  title?: string;
+
+  /**
+   * Detailed description of the layer.
+   * Maps to:
+   * - `abstract` for WMS, WFS, TMS
+   * - `description` for OGC API, STAC
+   */
+  description?: string;
+}
+
+/**
+ * Extended layer properties that most layers support.
+ * Includes common metadata fields found across different services.
+ */
+export interface BaseLayerExtended extends BaseLayerCore {
+  /**
+   * Keywords/tags associated with the layer.
+   * Used for search and categorization.
+   */
+  keywords?: string[];
+
+  /**
+   * Bounding box in WGS84 (EPSG:4326) coordinates.
+   * Format: [minx, miny, maxx, maxy]
+   *
+   * This is normalized across services:
+   * - WMS: Uses boundingBoxes['EPSG:4326'] or boundingBoxes['CRS:84']
+   * - WFS: Uses boundingBox or latLonBoundingBox
+   * - WMTS: Uses latLonBoundingBox
+   * - OGC API: Uses extent.spatial.bbox[0]
+   * - STAC: Uses extent.spatial.bbox[0]
+   * - TMS: Uses boundingBox (may not be WGS84)
+   */
+  boundingBox?: BoundingBox;
+
+  /**
+   * Metadata URLs providing additional information about the layer.
+   * Links to ISO metadata, FGDC records, etc.
+   */
+  metadata?: MetadataURL[];
+}

src/stac/model.ts

@@ -1,4 +1,5 @@
 import { Feature, Geometry } from 'geojson';
+import { BoundingBox } from '../shared/models';
 
 /**
  * STAC specification version 1.0.0
@@ -10,7 +11,7 @@
  * or [minx, miny, minz, maxx, maxy, maxz] for 3D
  */
 export type StacBBox =
-  | [number, number, number, number]
+  | BoundingBox
   | [number, number, number, number, number, number];
 
 /**

src/wms/capabilities.ts

@@ -318,9 +318,9 @@ function parseLayer(
     )
   );
   return {
-    name: getElementText(findChildElement(layerEl, 'Name')),
+    id: getElementText(findChildElement(layerEl, 'Name')),
     title: getElementText(findChildElement(layerEl, 'Title')),
-    abstract: getElementText(findChildElement(layerEl, 'Abstract')),
+    description: getElementText(findChildElement(layerEl, 'Abstract')),
     availableCrs,
     styles,
     attribution,

src/wms/endpoint.ts

@@ -10,13 +10,15 @@ import {
   type OperationName,
   type OperationUrl,
 } from '../shared/models.js';
+import { BaseEndpoint } from '../shared/base-endpoint.js';
+import type { BaseLayerExtended } from '../shared/base-layer.js';
 import { WmsLayerFull, WmsLayerSummary, WmsVersion } from './model.js';
 import { generateGetMapUrl } from './url.js';
 
 /**
  * Represents a WMS endpoint advertising several layers arranged in a tree structure.
  */
-export default class WmsEndpoint {
+export default class WmsEndpoint implements BaseEndpoint {
   private _capabilitiesUrl: string;
   private _capabilitiesPromise: Promise<void>;
   private _info: GenericEndpointInfo | null;
@@ -66,15 +68,16 @@ export default class WmsEndpoint {
   }
 
   /**
-   * Returns an array of layers in summary format; layers are organized in a tree
-   * structure with each having an optional `children` property
+   * Returns an array of layers in tree structure with summary information.
+   * This preserves the WMS hierarchical layer organization.
+   * For a flat list, use getLayers() instead.
    */
-  getLayers() {
+  getLayersTree() {
     function layerSummaryMapper(layerFull) {
       return {
         title: layerFull.title,
-        name: layerFull.name,
-        abstract: layerFull.abstract,
+        id: layerFull.id,
+        description: layerFull.description,
         ...('children' in layerFull && {
           children: layerFull.children.map(layerSummaryMapper),
         }),
@@ -84,10 +87,30 @@ export default class WmsEndpoint {
   }
 
   /**
-   * Returns a array of layers, same as WmsEndpoint.getLayers(), but flattened
+   * Returns a flat array of all layers in normalized format.
+   * Implements the BaseEndpoint generic interface.
+   * @returns Array of layers with extended information
+   */
+  getLayers(): WmsLayerSummary[] {
+    return this.getFlattenedLayers();
+  }
+
+  /**
+   * Get a specific layer by its identifier in normalized format.
+   * Implements the BaseEndpoint generic interface.
+   * @param id The layer name (WMS uses 'name' as identifier)
+   * @returns Layer with extended information, or null if not found
+   */
+  getLayerById(id: string): BaseLayerExtended | null {
+    return this.getLayerByName(id);
+  }
+
+  /**
+   * Returns a array of layers in flattened format (WMS-specific summary format).
+   * For normalized BaseLayer format, use getLayers() instead.
    */
   getFlattenedLayers() {
-    return this.getLayers().flatMap(wmsLayerFlatten);
+    return this.getLayersTree().flatMap(wmsLayerFlatten);
   }
 
   /**
@@ -119,15 +142,15 @@ export default class WmsEndpoint {
     if (!this._layers) return null;
     const layers: WmsLayerFull[] = [];
     function layerLookup(layer: WmsLayerFull) {
-      if (layer.name) {
+      if (layer.id) {
         layers.push(layer);
       }
       if ('children' in layer) {
         layer.children.map(layerLookup);
       }
     }
     this._layers.map(layerLookup);
-    if (layers.length === 1) return layers[0].name;
+    if (layers.length === 1) return layers[0].id;
     return null;
   }
 
@@ -217,7 +240,7 @@ function wmsLayerFlatten(layerFull) {
   const layer = {
     title: layerFull.title,
     name: layerFull.name,
-    abstract: layerFull.abstract,
+    description: layerFull.description,
   };
 
   return 'children' in layerFull && Array.isArray(layerFull.children)

src/wms/model.ts

@@ -4,33 +4,25 @@
   LayerStyle,
   type MetadataURL,
 } from '../shared/models.js';
+import { BaseLayerCore } from '../shared/base-layer';
 
 export type WmsLayerAttribution = {
   title?: string;
   url?: string;
   logoUrl?: string;
 };
 
-export type WmsLayerSummary = {
-  /**
-   * The layer is renderable if defined
-   */
-  name?: string;
-  title: string;
-  abstract?: string;
+export interface WmsLayerSummary extends BaseLayerCore {
   /**
    * Not defined if the layer is a leaf in the tree
    */
   children?: WmsLayerSummary[];
-};
+}
 
-export type WmsLayerFull = {
+export interface WmsLayerFull extends Exclude<WmsLayerSummary, 'children'> {
   /**
    * The layer is renderable if defined
    */
-  name?: string;
-  title: string;
-  abstract?: string;
   availableCrs: CrsCode[];
   styles: LayerStyle[];
   /**
@@ -48,6 +40,6 @@
    * Not defined if the layer is a leaf in the tree
    */
   children?: WmsLayerFull[];
-};
+}
 
 export type WmsVersion = '1.1.0' | '1.1.1' | '1.3.0';