Handle the language context

packages/applications/turbo-blog/src/build/build.ts

@@ -1,8 +1,12 @@
 import { Router } from "ssg-router";
+import type { Context } from "./context/context";
 import { generateIndexPage } from "./handlers/index/generate";
 import { outputIndexPage } from "./handlers/index/output";
+import { registerLanguagePlugin } from "./plugin/language";
 
-const router = new Router();
+const router = new Router<Context>();
+
+router.register(registerLanguagePlugin);
 
 router.on("/", {
 	generate: generateIndexPage,

packages/applications/turbo-blog/src/build/context/context.ts

@@ -0,0 +1,3 @@
+export type Context = {
+	language: "ja" | "en";
+};

packages/applications/turbo-blog/src/build/handlers/index/generate.tsx

@@ -1,20 +1,25 @@
 import fs from "node:fs/promises";
 import nodePath from "node:path";
 import { renderToStaticMarkup } from "react-dom/server";
+import type { GenerateHandler } from "ssg-router";
 import { Layout } from "../../../ui/components/Layout/Layout";
 import { Home } from "../../../ui/pages/Home/Home";
 import { GetBlogPostsUsecase } from "../../application/getBlogPosts/getBlogposts.usecase";
+import type { Context } from "../../context/context";
 import { BlogRepository } from "../../model/blog/blog.repository";
 import { Shell } from "../../util/helmet";
 
-export const generateIndexPage: () => Promise<string> = async () => {
+export const generateIndexPage: GenerateHandler<Context> = async ({
+	context,
+}) => {
 	const blogRepository = new BlogRepository(fs, nodePath);
 	const getblogPostsUsecase = new GetBlogPostsUsecase(blogRepository);
 	const blogPosts = await getblogPostsUsecase.getBlogPosts();
+	const language = context.language;
 
 	return renderToStaticMarkup(
-		<Shell language="ja" which="TODO" title="shinyaigeek.dev" slug="/">
-			<Layout language="ja" page="1" currentPath="/">
+		<Shell language={language} which="TODO" title="shinyaigeek.dev" slug="/">
+			<Layout language={language} page="1" currentPath="/">
 				<Home />
 			</Layout>
 		</Shell>,

packages/applications/turbo-blog/src/build/plugin/language.ts

@@ -0,0 +1,8 @@
+import type { Plugin } from "ssg-router";
+import type { Context } from "../context/context";
+
+export const registerLanguagePlugin: Plugin<Context> = {
+	async onRouted(_, context) {
+		context.language = "ja";
+	},
+};

packages/modules/ssg-router/src/index.ts

@@ -1,2 +1,6 @@
-export { Router } from "./router/router";
+export {
+	Router,
+	type GenerateHandler,
+	type OutputHandler,
+} from "./router/router";
 export type { Plugin } from "./plugin/basic";

packages/modules/ssg-router/src/plugin/basic.ts

@@ -1,5 +1,5 @@
 export type Plugin<RoutingContext> = {
-	onRouted: (path: string, context: RoutingContext) => Promise<void>;
-	onGenerated: (path: string, content: string) => Promise<void>;
-	onOutput: (path: string) => Promise<void>;
+	onRouted?: (path: string, context: RoutingContext) => Promise<void>;
+	onGenerated?: (path: string, content: string) => Promise<void>;
+	onOutput?: (path: string) => Promise<void>;
 };

packages/modules/ssg-router/src/router/router.ts

@@ -1,6 +1,8 @@
 import type { Plugin } from "../plugin/basic";
 import type { BasicRouter, GenerateHandler, OutputHandler } from "./basic";
 
+export type { GenerateHandler, OutputHandler } from "./basic";
+
 export class Router<RoutingContext> implements BasicRouter<RoutingContext> {
 	private routing: Map<
 		string,