packages/core: added AppThemeSelector

packages/core/src/api/apis/definitions/AppThemeApi.ts

@@ -51,7 +51,7 @@ export type AppThemeApi = {
   /**
    * Get a list of available themes.
    */
-  getThemeOptions(): AppTheme[];
+  getInstalledThemes(): AppTheme[];
 
   /**
    * Observe the currently selected theme. A value of undefined means no specific theme has been selected.

packages/core/src/api/apis/implementations/AppThemeSelector/AppThemeSelector.test.ts

@@ -0,0 +1,48 @@
+/*
+ * Copyright 2020 Spotify AB
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { AppTheme } from '../../definitions';
+import { AppThemeSelector } from './AppThemeSelector';
+
+describe('AppThemeSelector', () => {
+  it('should should select new themes', async () => {
+    const selector = new AppThemeSelector([]);
+
+    expect(selector.getInstalledThemes()).toEqual([]);
+
+    const subFn = jest.fn();
+    selector.activeThemeId$().subscribe(subFn);
+    expect(selector.getActiveThemeId()).toBe(undefined);
+    await 'wait a tick';
+    expect(subFn).toHaveBeenLastCalledWith(undefined);
+
+    selector.setActiveThemeId('x');
+    expect(subFn).toHaveBeenLastCalledWith('x');
+    expect(selector.getActiveThemeId()).toBe('x');
+
+    selector.setActiveThemeId(undefined);
+    expect(subFn).toHaveBeenLastCalledWith(undefined);
+    expect(selector.getActiveThemeId()).toBe(undefined);
+  });
+
+  it('should return a new array of themes', () => {
+    const themes = new Array<AppTheme>();
+    const selector = new AppThemeSelector(themes);
+
+    expect(selector.getInstalledThemes()).toEqual(themes);
+    expect(selector.getInstalledThemes()).not.toBe(themes);
+  });
+});

packages/core/src/api/apis/implementations/AppThemeSelector/AppThemeSelector.ts

@@ -0,0 +1,59 @@
+/*
+ * Copyright 2020 Spotify AB
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import Observable from 'zen-observable';
+import { AppThemeApi, AppTheme } from '../../definitions';
+
+export class AppThemeSelector implements AppThemeApi {
+  private readonly themes: AppTheme[];
+
+  private activeThemeId: string | undefined;
+
+  private readonly observable: Observable<string | undefined>;
+  private readonly subscribers = new Set<
+    ZenObservable.SubscriptionObserver<string | undefined>
+  >();
+
+  constructor(themes: AppTheme[]) {
+    this.themes = themes;
+
+    this.observable = new Observable((subscriber) => {
+      subscriber.next(this.activeThemeId);
+
+      this.subscribers.add(subscriber);
+      return () => {
+        this.subscribers.delete(subscriber);
+      };
+    });
+  }
+
+  getInstalledThemes(): AppTheme[] {
+    return this.themes.slice();
+  }
+
+  activeThemeId$(): Observable<string | undefined> {
+    return this.observable;
+  }
+
+  getActiveThemeId(): string | undefined {
+    return this.activeThemeId;
+  }
+
+  setActiveThemeId(themeId?: string): void {
+    this.activeThemeId = themeId;
+    this.subscribers.forEach((subscriber) => subscriber.next(themeId));
+  }
+}

packages/core/src/api/apis/implementations/AppThemeSelector/index.ts

@@ -0,0 +1,17 @@
+/*
+ * Copyright 2020 Spotify AB
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+export * from './AppThemeSelector';

packages/core/src/api/apis/implementations/index.ts

@@ -18,6 +18,7 @@
 //
 // Plugins should rely on these APIs for functionality as much as possible.
 
+export * from './AppThemeSelector';
 export * from './AlertApiForwarder';
 export * from './ErrorApiForwarder';
 export * from './OAuthRequestManager';