create and update the main API Route

src/app/api/generate/route.ts

@@ -0,0 +1,96 @@
+import { NextResponse } from "next/server";
+import { getGeminiModel } from "@/lib/gemini";
+import { getRepoData, getRepoContents } from "@/lib/octokit";
+
+// Ensure API keys are read at runtime
+export const dynamic = "force-dynamic";
+
+export async function POST(req: Request) {
+  // 1. Safe JSON Body Parsing
+  let rawUrl: string;
+  try {
+    const body = await req.json();
+    rawUrl = body.url;
+  } catch {
+    return NextResponse.json({ error: "Invalid JSON body" }, { status: 400 });
+  }
+
+  try {
+    // 2. Strict URL Validation
+    const trimmedUrl = rawUrl?.trim();
+    if (!trimmedUrl) {
+      return NextResponse.json({ error: "GitHub URL is required" }, { status: 400 });
+    }
+
+    let parsedUrl: URL;
+    try {
+      parsedUrl = new URL(trimmedUrl);
+    } catch {
+      return NextResponse.json({ error: "Please provide a valid URL" }, { status: 400 });
+    }
+
+    // Hostname Guard
+    if (parsedUrl.hostname !== "github.com" && parsedUrl.hostname !== "www.github.com") {
+      return NextResponse.json({ error: "Only GitHub URLs are supported" }, { status: 400 });
+    }
+
+    // Extract Owner and Repo from path
+    const pathSegments = parsedUrl.pathname.split("/").filter(Boolean);
+    const owner = pathSegments[0];
+    const repo = pathSegments[1];
+
+    if (!owner || !repo) {
+      return NextResponse.json({ error: "URL must include owner and repository name" }, { status: 400 });
+    }
+
+    // 3. Parallel Data Fetching
+    const [repoInfo, repoContents] = await Promise.all([
+      getRepoData(owner, repo),
+      getRepoContents(owner, repo)
+    ]);
+
+    // 4. Type-Safe File Mapping (Fixes the 'any' linting error)
+    // We define the shape { name: string } inline to satisfy ESLint
+    const fileList = Array.isArray(repoContents) && repoContents.length > 0 
+      ? repoContents.map((f: { name: string }) => f.name).join(", ") 
+      : "Standard repository structure";
+
+    // 5. Initialize Gemini 2.5
+    const model = getGeminiModel();
+
+    // 6. The "Expert Prompt" with Fallbacks
+    const prompt = `
+      You are an expert Technical Writer. Generate a professional README.md for:
+
+      Name: ${repo}
+      Description: ${repoInfo?.description || "A modern software project."}
+      Primary Language: ${repoInfo?.language || "Not specified"}
+      Root Directory Files: ${fileList}
+
+      Requirements:
+      - Include professional SVG badges from shields.io.
+      - Create a visual "Directory Structure" section (tree style).
+      - Include "Features", "Installation", and "Usage" sections.
+      - If 'package.json' exists, provide Node.js installation steps.
+      - Ensure a welcoming, professional developer-centric tone.
+
+      Return ONLY the Markdown content.
+    `;
+
+    // 7. AI Generation
+    const result = await model.generateContent(prompt);
+    const response = await result.response;
+    const markdown = response.text();
+
+    return NextResponse.json({ markdown });
+
+  } catch (error: unknown) {
+    const message = error instanceof Error ? error.message : "Internal Server Error";
+    console.error("README Generation Failed:", message);
+
+    return NextResponse.json(
+      { error: "Failed to generate README. Check your URL and try again." },
+      { status: 500 }
+    );
+  }
+}

src/lib/octokit.ts

@@ -1,15 +1,12 @@
 import { Octokit } from "octokit";
 
-// Private variable for Singleton pattern
 let _octokit: Octokit | null = null;
 
 export function getOctokit(): Octokit {
   if (_octokit) return _octokit;
 
   const auth = process.env.GITHUB_TOKEN;
 
-  // We don't throw an error here because Octokit can work without a token 
-  // (unauthenticated), though it will be heavily rate-limited.
   _octokit = new Octokit({
     auth: auth || undefined,
   });
@@ -18,8 +15,7 @@ export function getOctokit(): Octokit {
 }
 
 /**
- * Fetches repository metadata safely.
- * Notice we only log the error message, NOT the full error object.
+ * Fetches repository metadata (stars, description, language)
  */
 export async function getRepoData(owner: string, repo: string) {
   const client = getOctokit();
@@ -32,8 +28,29 @@ export async function getRepoData(owner: string, repo: string) {
     return data;
   } catch (error: unknown) {
     const message = error instanceof Error ? error.message : "An unknown error occurred";
-    console.error("Error fetching GitHub repo:", message);
-
+    console.error("Error fetching GitHub repo metadata:", message);
     return null;
   }
 }
+
+/**
+ * NEW: Fetches the root contents to help Gemini build the File Structure
+ */
+export async function getRepoContents(owner: string, repo: string) {
+  const client = getOctokit();
+
+  try {
+    const { data } = await client.rest.repos.getContent({
+      owner,
+      repo,
+      path: "", // Root directory
+    });
+
+    // Return the array of files/folders
+    return Array.isArray(data) ? data : [];
+  } catch (error: unknown) {
+    const message = error instanceof Error ? error.message : "Could not fetch contents";
+    console.error("Error fetching GitHub repo contents:", message);
+    return [];
+  }
+}

tsconfig.json

@@ -18,8 +18,9 @@
         "name": "next"
       }
     ],
+    "baseUrl": ".", 
     "paths": {
-      "@/*": ["./*"]
+      "@/*": ["./src/*"] 
     }
   },
   "include": [
@@ -31,4 +32,4 @@
     "**/*.mts"
   ],
   "exclude": ["node_modules"]
-}
+}