refactor(navigation): factory-style use case + controller

- Use case (get-header) → factory function with IGetHeaderUseCase alias
- Controller renamed header.controller.ts → get-header.controller.ts (verb-noun); converted to factory function with IGetHeaderController alias
- DI module wires factories with .toDynamicValue()
- tRPC router resolves controller via container
- Use case + controller tests refactored to direct factory injection (no container rebinding)
- container.test.ts verifies IGetHeaderUseCase + IGetHeaderController symbols

Refactor log: §1, §4.1, §4.2, §5.1
Spec: §6.4

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/navigation/src/application/use-cases/get-header.use-case.test.ts

@@ -1,22 +1,12 @@
-import { beforeEach, describe, expect, it } from "vitest";
-import { navigationContainer } from "@/di/container";
-import { NAVIGATION_SYMBOLS } from "@/di/symbols";
+import { describe, expect, it } from "vitest";
+import { getHeaderUseCase } from "@/application/use-cases/get-header.use-case";
 import { MockHeaderRepository } from "@/infrastructure/repositories/header.repository.mock";
-import type { IHeaderRepository } from "@/application/repositories/header.repository.interface";
-import { getHeaderUseCase } from "./get-header.use-case";
 
 describe("getHeaderUseCase", () => {
-  beforeEach(() => {
-    if (navigationContainer.isBound(NAVIGATION_SYMBOLS.IHeaderRepository)) {
-      navigationContainer.unbind(NAVIGATION_SYMBOLS.IHeaderRepository);
-    }
-    navigationContainer
-      .bind<IHeaderRepository>(NAVIGATION_SYMBOLS.IHeaderRepository)
-      .toConstantValue(new MockHeaderRepository());
-  });
-
   it("returns the seeded header items", async () => {
-    const result = await getHeaderUseCase();
+    const repo = new MockHeaderRepository();
+    const useCase = getHeaderUseCase(repo);
+    const result = await useCase();
     expect(result.items.length).toBeGreaterThan(0);
     expect(result.items[0]?.label).toBe("Home");
   });

packages/navigation/src/application/use-cases/get-header.use-case.ts

@@ -1,11 +1,10 @@
 import type { Header } from "../../entities/models/header";
-import { navigationContainer } from "../../di/container";
-import { NAVIGATION_SYMBOLS } from "../../di/symbols";
 import type { IHeaderRepository } from "../repositories/header.repository.interface";
 
-export async function getHeaderUseCase(): Promise<Header> {
-  const repo = navigationContainer.get<IHeaderRepository>(
-    NAVIGATION_SYMBOLS.IHeaderRepository,
-  );
-  return repo.getHeader();
-}
+export type IGetHeaderUseCase = ReturnType<typeof getHeaderUseCase>;
+
+export const getHeaderUseCase =
+  (headerRepository: IHeaderRepository) =>
+  async (): Promise<Header> => {
+    return headerRepository.getHeader();
+  };

packages/navigation/src/di/container.test.ts

@@ -4,6 +4,8 @@ import { NAVIGATION_SYMBOLS } from "./symbols";
 import { NavigationModule } from "./module";
 import { MockHeaderRepository } from "@/infrastructure/repositories/header.repository.mock";
 import type { IHeaderRepository } from "@/application/repositories/header.repository.interface";
+import type { IGetHeaderUseCase } from "@/application/use-cases/get-header.use-case";
+import type { IGetHeaderController } from "@/interface-adapters/controllers/get-header.controller";
 
 describe("navigationContainer", () => {
   beforeEach(() => {
@@ -21,4 +23,18 @@ describe("navigationContainer", () => {
     );
     expect(repo).toBeInstanceOf(MockHeaderRepository);
   });
+
+  it("resolves IGetHeaderUseCase as a function", () => {
+    const useCase = navigationContainer.get<IGetHeaderUseCase>(
+      NAVIGATION_SYMBOLS.IGetHeaderUseCase,
+    );
+    expect(typeof useCase).toBe("function");
+  });
+
+  it("resolves IGetHeaderController as a function", () => {
+    const controller = navigationContainer.get<IGetHeaderController>(
+      NAVIGATION_SYMBOLS.IGetHeaderController,
+    );
+    expect(typeof controller).toBe("function");
+  });
 });

packages/navigation/src/di/module.ts

@@ -2,10 +2,32 @@ import { ContainerModule, type interfaces } from "inversify";
 
 import type { IHeaderRepository } from "../application/repositories/header.repository.interface";
 import { MockHeaderRepository } from "../infrastructure/repositories/header.repository.mock";
+import {
+  getHeaderUseCase,
+  type IGetHeaderUseCase,
+} from "../application/use-cases/get-header.use-case";
+import {
+  getHeaderController,
+  type IGetHeaderController,
+} from "../interface-adapters/controllers/get-header.controller";
 import { NAVIGATION_SYMBOLS } from "./symbols";
 
 export const NavigationModule = new ContainerModule((bind: interfaces.Bind) => {
   bind<IHeaderRepository>(NAVIGATION_SYMBOLS.IHeaderRepository).to(
     MockHeaderRepository,
   );
+
+  bind<IGetHeaderUseCase>(NAVIGATION_SYMBOLS.IGetHeaderUseCase).toDynamicValue(
+    (ctx) =>
+      getHeaderUseCase(
+        ctx.container.get<IHeaderRepository>(NAVIGATION_SYMBOLS.IHeaderRepository),
+      ),
+  );
+
+  bind<IGetHeaderController>(NAVIGATION_SYMBOLS.IGetHeaderController).toDynamicValue(
+    (ctx) =>
+      getHeaderController(
+        ctx.container.get<IGetHeaderUseCase>(NAVIGATION_SYMBOLS.IGetHeaderUseCase),
+      ),
+  );
 });

packages/navigation/src/di/symbols.ts

@@ -1,3 +1,7 @@
 export const NAVIGATION_SYMBOLS = {
   IHeaderRepository: Symbol.for("navigation:IHeaderRepository"),
+  // Use cases
+  IGetHeaderUseCase: Symbol.for("navigation:IGetHeaderUseCase"),
+  // Controllers
+  IGetHeaderController: Symbol.for("navigation:IGetHeaderController"),
 } as const;

packages/navigation/src/integrations/api/router.test.ts

@@ -1,20 +1,7 @@
-import { beforeEach, describe, expect, it } from "vitest";
-import { navigationContainer } from "@/di/container";
-import { NAVIGATION_SYMBOLS } from "@/di/symbols";
-import { MockHeaderRepository } from "@/infrastructure/repositories/header.repository.mock";
-import type { IHeaderRepository } from "@/application/repositories/header.repository.interface";
+import { describe, expect, it } from "vitest";
 import { navigationRouter } from "./router";
 
 describe("navigationRouter", () => {
-  beforeEach(() => {
-    if (navigationContainer.isBound(NAVIGATION_SYMBOLS.IHeaderRepository)) {
-      navigationContainer.unbind(NAVIGATION_SYMBOLS.IHeaderRepository);
-    }
-    navigationContainer
-      .bind<IHeaderRepository>(NAVIGATION_SYMBOLS.IHeaderRepository)
-      .toConstantValue(new MockHeaderRepository());
-  });
-
   it("exposes header procedure", () => {
     const names = Object.keys(navigationRouter._def.procedures);
     expect(names).toContain("header");

packages/navigation/src/integrations/api/router.ts

@@ -1,8 +1,15 @@
 import { router, publicProcedure } from "@repo/core-shared/trpc/init";
-import { getHeaderController } from "../../interface-adapters/controllers/header.controller";
+import { navigationContainer } from "../../di/container";
+import { NAVIGATION_SYMBOLS } from "../../di/symbols";
+import type { IGetHeaderController } from "../../interface-adapters/controllers/get-header.controller";
 
 export const navigationRouter = router({
-  header: publicProcedure.query(() => getHeaderController()),
+  header: publicProcedure.query(() => {
+    const ctrl = navigationContainer.get<IGetHeaderController>(
+      NAVIGATION_SYMBOLS.IGetHeaderController,
+    );
+    return ctrl();
+  }),
 });
 
 export type NavigationRouter = typeof navigationRouter;

packages/navigation/src/interface-adapters/controllers/get-header.controller.test.ts

@@ -0,0 +1,17 @@
+import { describe, expect, it } from "vitest";
+import { getHeaderController } from "@/interface-adapters/controllers/get-header.controller";
+import { getHeaderUseCase } from "@/application/use-cases/get-header.use-case";
+import { MockHeaderRepository } from "@/infrastructure/repositories/header.repository.mock";
+
+describe("getHeaderController", () => {
+  it("returns the header with items", async () => {
+    const repo = new MockHeaderRepository();
+    const useCase = getHeaderUseCase(repo);
+    const controller = getHeaderController(useCase);
+
+    const result = await controller();
+
+    expect(result.items.length).toBeGreaterThan(0);
+    expect(result.items[0]?.label).toBe("Home");
+  });
+});

packages/navigation/src/interface-adapters/controllers/get-header.controller.ts

@@ -0,0 +1,10 @@
+import type { Header } from "../../entities/models/header";
+import type { IGetHeaderUseCase } from "../../application/use-cases/get-header.use-case";
+
+export type IGetHeaderController = ReturnType<typeof getHeaderController>;
+
+export const getHeaderController =
+  (getHeaderUseCase: IGetHeaderUseCase) =>
+  async (): Promise<Header> => {
+    return getHeaderUseCase();
+  };

packages/navigation/src/interface-adapters/controllers/header.controller.ts

@@ -1,6 +0,0 @@
-import type { Header } from "../../entities/models/header";
-import { getHeaderUseCase } from "../../application/use-cases/get-header.use-case";
-
-export async function getHeaderController(): Promise<Header> {
-  return getHeaderUseCase();
-}