From 2fcadae9df42e0decb73127828f688125c3153c1 Mon Sep 17 00:00:00 2001
From: Patrik Oldsberg <poldsberg@gmail.com>
Date: Tue, 12 Sep 2023 11:19:52 +0200
Subject: [PATCH] core-plugin-api: additional translation ref refactor

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>
---
 .../src/translation/TranslationRef.test.ts    | 62 +++++++++-----
 .../src/translation/TranslationRef.ts         | 80 ++++++++++++-------
 2 files changed, 92 insertions(+), 50 deletions(-)

diff --git a/packages/core-plugin-api/src/translation/TranslationRef.test.ts b/packages/core-plugin-api/src/translation/TranslationRef.test.ts
index 41d5d9ab85..b73b521774 100644
--- a/packages/core-plugin-api/src/translation/TranslationRef.test.ts
+++ b/packages/core-plugin-api/src/translation/TranslationRef.test.ts
@@ -17,39 +17,57 @@ import {
   createTranslationRef,
   toInternalTranslationRef,
 } from './TranslationRef';
+import { toInternalTranslationResource } from './TranslationResource';
 
 describe('TranslationRefImpl', () => {
   it('should create a TranslationRef instance using the factory function', () => {
-    const config = {
-      id: 'testId',
+    const ref = createTranslationRef({
+      id: 'test',
       messages: { key: 'value' },
-    };
+    });
 
-    const translationRef = toInternalTranslationRef(
-      createTranslationRef(config),
-    );
+    const internalRef = toInternalTranslationRef(ref);
 
-    expect(translationRef.id).toBe('testId');
-    expect(translationRef.getDefaultMessages()).toEqual({ key: 'value' });
+    expect(internalRef.$$type).toBe('@backstage/TranslationRef');
+    expect(internalRef.version).toBe('v1');
+    expect(internalRef.id).toBe('test');
+    expect(internalRef.getDefaultMessages()).toEqual({ key: 'value' });
   });
 
-  it('should get lazy resources', async () => {
-    const config = {
-      id: 'testId',
+  it('should be created with lazy translations', async () => {
+    const ref = createTranslationRef({
+      id: 'test',
       messages: { key: 'value' },
-      lazyResources: {
-        en: () => Promise.resolve({ messages: { key: 'value' } }),
+      translations: {
+        de: () => Promise.resolve({ default: { key: 'other-value' } }),
       },
-    };
+    });
 
-    const translationRef = toInternalTranslationRef(
-      createTranslationRef(config),
+    const internalRef = toInternalTranslationRef(ref);
+
+    expect(internalRef.$$type).toBe('@backstage/TranslationRef');
+    expect(internalRef.version).toBe('v1');
+    expect(internalRef.id).toBe('test');
+    expect(internalRef.getDefaultMessages()).toEqual({ key: 'value' });
+
+    const internalResource = toInternalTranslationResource(
+      internalRef.getDefaultResource()!,
     );
-
-    const lazyResources = translationRef.getLazyResources();
-
-    const messages = await lazyResources?.en();
-
-    expect(messages).toEqual({ messages: { key: 'value' } });
+    expect(internalResource).toEqual({
+      $$type: '@backstage/TranslationResource',
+      version: 'v1',
+      id: 'test',
+      resources: [
+        {
+          language: 'de',
+          loader: expect.any(Function),
+        },
+      ],
+    });
+    await expect(internalResource.resources[0].loader()).resolves.toEqual({
+      messages: {
+        key: 'other-value',
+      },
+    });
   });
 });
diff --git a/packages/core-plugin-api/src/translation/TranslationRef.ts b/packages/core-plugin-api/src/translation/TranslationRef.ts
index 2a135fe825..91b5d7850d 100644
--- a/packages/core-plugin-api/src/translation/TranslationRef.ts
+++ b/packages/core-plugin-api/src/translation/TranslationRef.ts
@@ -14,10 +14,15 @@
  * limitations under the License.
  */
 
+import {
+  createTranslationResource,
+  TranslationResource,
+} from './TranslationResource';
+
 /** @alpha */
 export interface TranslationRef<
-  TMessages extends { [key in string]: string } = { [key in string]: string },
   TId extends string = string,
+  TMessages extends { [key in string]: string } = { [key in string]: string },
 > {
   $$type: '@backstage/TranslationRef';
 
@@ -31,47 +36,54 @@ type AnyMessages = { [key in string]: string };
 
 /** @internal */
 export interface InternalTranslationRef<
-  TMessages extends { [key in string]: string } = { [key in string]: string },
   TId extends string = string,
-> extends TranslationRef<TMessages, TId> {
+  TMessages extends { [key in string]: string } = { [key in string]: string },
+> extends TranslationRef<TId, TMessages> {
   version: 'v1';
 
   getDefaultMessages(): AnyMessages;
 
-  getResources(): Record<string, AnyMessages> | undefined;
-
-  getLazyResources():
-    | Record<string, () => Promise<{ messages: AnyMessages }>>
-    | undefined;
+  getDefaultResource(): TranslationResource | undefined;
 }
 
+export type NoInfer<T> = T extends infer S ? S : never;
+
 /** @alpha */
 export interface TranslationRefOptions<
+  TId extends string,
   TMessages extends { [key in string]: string },
-  TId extends string = string,
+  TTranslations extends {
+    [language in string]: () => Promise<{
+      default: { [key in keyof TMessages]: string | null };
+    }>;
+  },
 > {
   id: TId;
   messages: TMessages;
-  lazyResources?: Record<string, () => Promise<{ messages: TMessages }>>;
-  resources?: Record<string, TMessages>;
+  translations?: TTranslations;
 }
 
 /** @internal */
 class TranslationRefImpl<
+  TId extends string,
   TMessages extends { [key in string]: string },
-  TId extends string = string,
-> implements InternalTranslationRef<TMessages, TId>
+> implements InternalTranslationRef<TId, TMessages>
 {
-  constructor(
-    private readonly options: TranslationRefOptions<TMessages, TId>,
-  ) {}
+  #id: TId;
+  #messages: TMessages;
+  #resources: TranslationResource | undefined;
+
+  constructor(options: TranslationRefOptions<TId, TMessages, any>) {
+    this.#id = options.id;
+    this.#messages = options.messages;
+  }
 
   $$type = '@backstage/TranslationRef' as const;
 
   version = 'v1' as const;
 
   get id(): TId {
-    return this.options.id;
+    return this.#id;
   }
 
   get T(): never {
@@ -79,17 +91,15 @@ class TranslationRefImpl<
   }
 
   getDefaultMessages(): AnyMessages {
-    return this.options.messages;
+    return this.#messages;
   }
 
-  getLazyResources():
-    | Record<string, () => Promise<{ messages: AnyMessages }>>
-    | undefined {
-    return this.options.lazyResources;
+  setDefaultResource(resources: TranslationResource): void {
+    this.#resources = resources;
   }
 
-  getResources(): Record<string, AnyMessages> | undefined {
-    return this.options.resources;
+  getDefaultResource(): TranslationResource | undefined {
+    return this.#resources;
   }
 
   toString() {
@@ -99,12 +109,26 @@ class TranslationRefImpl<
 
 /** @alpha */
 export function createTranslationRef<
+  TId extends string,
   TMessages extends { [key in string]: string },
-  TId extends string = string,
+  TTranslations extends {
+    [language in string]: () => Promise<{
+      default: { [key in keyof TMessages]: string | null };
+    }>;
+  },
 >(
-  config: TranslationRefOptions<TMessages, TId>,
-): TranslationRef<TMessages, TId> {
-  return new TranslationRefImpl(config);
+  config: TranslationRefOptions<TId, TMessages, TTranslations>,
+): TranslationRef<TId, TMessages> {
+  const ref = new TranslationRefImpl(config);
+  if (config.translations) {
+    ref.setDefaultResource(
+      createTranslationResource({
+        ref,
+        translations: config.translations as any,
+      }),
+    );
+  }
+  return ref;
 }
 
 /** @internal */