add audio downloader

docs/.vitepress/config.mts

@@ -1,3 +1,8 @@
+import fs from "node:fs";
+import { IncomingMessage, ServerResponse } from "node:http";
+import https from "node:https";
+import path from "node:path";
+import { Connect, Plugin, ViteDevServer } from "vite";
 import { defineConfig, MarkdownOptions } from "vitepress";
 
 const host = process.env.TAURI_DEV_HOST;
@@ -9,7 +14,7 @@ export default defineConfig({
   lang: "ko-KR",
   themeConfig: {
     socialLinks: [
-      { icon: "github", link: "https://github.com/vuejs/vitepress" },
+      { icon: "github", link: "https://git.polv.cc/polv/ko-grammar" },
     ],
     outline: {
       level: "deep",
@@ -65,6 +70,7 @@ export default defineConfig({
     },
   },
   vite: {
+    plugins: [audioProxyPlugin() as any],
     envDir: process.cwd(),
     ssr: {
       noExternal: [],
@@ -107,3 +113,85 @@ export default defineConfig({
     },
   },
 });
+
+function audioProxyPlugin(): Plugin {
+  return {
+    name: "audio-proxy",
+    configureServer(server: ViteDevServer) {
+      // Vite dev server middlewares are connect-style: (req, res, next)
+      server.middlewares.use((req, res, next) => {
+        const reqUrl = req.url;
+        if (!reqUrl || !reqUrl.startsWith("/uploads/")) return next();
+        if (!reqUrl.endsWith(".mp3")) return next();
+
+        proxyAudio(req, res, next);
+      });
+    },
+  };
+}
+
+function proxyAudio(
+  req: Connect.IncomingMessage,
+  res: ServerResponse<IncomingMessage>,
+  next: Connect.NextFunction,
+) {
+  const url = new URL(
+    `https://www.howtostudykorean.com/wp-content/uploads${req.url}`,
+  );
+
+  // Forward common headers (important for Range streaming)
+  const headers = {
+    ...req.headers,
+    host: url.host,
+    range: req.headers["range"],
+  };
+
+  const segs = req.url!.slice(1).split("/");
+  const filename = segs.pop()!;
+  const saveroot = "docs/public";
+  const savetemp = path.join(saveroot, ...segs, filename + ".temp");
+  const saveto = path.join(saveroot, ...segs, filename);
+
+  if (fs.existsSync(saveto)) {
+    next();
+    return;
+  }
+
+  fs.mkdirSync(path.join(saveroot, ...segs), { recursive: true });
+  const fileStream = fs.createWriteStream(savetemp);
+
+  const upstreamReq = https.request(
+    {
+      protocol: url.protocol,
+      hostname: url.hostname,
+      port: url.port || undefined,
+      path: url.pathname + url.search,
+      method: req.method,
+      headers,
+    },
+    (upstreamRes) => {
+      // Pass status (200 or 206 for Range)
+      res.writeHead(upstreamRes.statusCode || 200, upstreamRes.headers);
+
+      // Stream through
+      upstreamRes.pipe(res);
+      upstreamRes.pipe(fileStream);
+    },
+  );
+
+  fileStream.on("finish", () => {
+    fs.renameSync(savetemp, saveto);
+    console.log("saved to", saveto);
+  });
+
+  fileStream.on("error", (err) => {
+    console.error("write failed:", err);
+  });
+
+  upstreamReq.on("error", (err) => {
+    res.statusCode = 502;
+    res.end(`Bad Gateway: ${err.message}`);
+  });
+
+  req.pipe(upstreamReq);
+}