Maintain a map to retrieve an enhancer for a commentspot.

Author: nedtwigg

browser-extension/src/lib/registries.ts

@@ -13,15 +13,23 @@ export interface EnhancedTextarea<T extends CommentSpot = CommentSpot> {
 export class EnhancerRegistry {
   private enhancers = new Set<CommentEnhancer>()
   private preparedEnhancers = new Set<CommentEnhancer>()
+  private byType = new Map<string, CommentEnhancer>()
 
   constructor() {
     // Register all available handlers
     this.register(new GitHubIssueAddCommentEnhancer())
     this.register(new GitHubPRAddCommentEnhancer())
   }
 
-  private register<T extends CommentSpot>(handler: CommentEnhancer<T>): void {
-    this.enhancers.add(handler)
+  private register<T extends CommentSpot>(enhancer: CommentEnhancer<T>): void {
+    this.enhancers.add(enhancer)
+    for (const spotType in enhancer.forSpotTypes()) {
+      this.byType.set(spotType, enhancer)
+    }
+  }
+
+  enhancerFor<T extends CommentSpot>(spot: T): CommentEnhancer<T> {
+    return this.byType.get(spot.type)! as CommentEnhancer<T>
   }
 
   tryToEnhance(textarea: HTMLTextAreaElement): EnhancedTextarea | null {