Minor fixes based on review comments

Author: hemanth5055

backend/src/index.ts

@@ -4,63 +4,50 @@ export interface Env {
 	GEMINI_API_KEY: string;
 }
 
-export default {
-	async fetch(request: Request, env: Env, ctx: ExecutionContext): Promise<Response> {
-		const corsHeaders = {
-			'Access-Control-Allow-Origin': '*',
-			'Access-Control-Allow-Methods': 'POST, OPTIONS',
-			'Access-Control-Allow-Headers': 'Content-Type',
-		};
+const corsHeaders = {
+	'Access-Control-Allow-Origin': '*',
+	'Access-Control-Allow-Methods': 'POST, OPTIONS',
+	'Access-Control-Allow-Headers': 'Content-Type',
+};
 
-		if (request.method === 'OPTIONS') {
-			return new Response(null, { headers: corsHeaders });
-		}
+async function handleTranslate(request: Request, model: ReturnType<GoogleGenerativeAI['getGenerativeModel']>) {
+	const { code, targetLanguage } = await request.json<{ code: string; targetLanguage: string }>();
 
-		const url = new URL(request.url);
-		const path = url.pathname;
-		const genAI = new GoogleGenerativeAI(env.GEMINI_API_KEY);
-		const model = genAI.getGenerativeModel({ model: 'gemini-2.0-flash' });
+	if (!code || !targetLanguage) {
+		return new Response(JSON.stringify({ error: "Missing 'code' or 'targetLanguage' in request body." }), {
+			status: 400,
+			headers: { ...corsHeaders, 'Content-Type': 'application/json' },
+		});
+	}
 
-		try {
-			//Function for handling the translation
-			const handleTranslate = async () => {
-				const { code, targetLanguage } = await request.json<{ code: string; targetLanguage: string }>();
-
-				if (!code || !targetLanguage) {
-					return new Response(JSON.stringify({ error: "Missing 'code' or 'targetLanguage' in request body." }), {
-						status: 400,
-						headers: { ...corsHeaders, 'Content-Type': 'application/json' },
-					});
-				}
-
-				const prompt = `Translate the following code snippet to ${targetLanguage}.
+	const prompt = `Translate the following code snippet to ${targetLanguage}.
 Do not add any explanation, commentary, or markdown formatting like \`\`\` around the code.
 **IMPORTANT: Preserve all original comments and their exact placement in the translated code. Do not add extra spaces in between.**
 Only provide the raw, translated code itself.
 
 Original Code:
 ${code}`;
 
-				const result = await model.generateContent(prompt);
-				const translatedCode = result.response.text();
-
-				return new Response(JSON.stringify({ translation: translatedCode }), {
-					status: 200,
-					headers: { ...corsHeaders, 'Content-Type': 'application/json' },
-				});
-			};
-			//Function for handling the explanation
-			const handleExplain = async () => {
-				const { code } = await request.json<{ code: string }>();
-
-				if (!code) {
-					return new Response(JSON.stringify({ error: "Missing 'code' in request body." }), {
-						status: 400,
-						headers: { ...corsHeaders, 'Content-Type': 'application/json' },
-					});
-				}
-
-				const prompt = `Explain the following code snippet in detail:
+	const result = await model.generateContent(prompt);
+	const translatedCode = result.response.text();
+
+	return new Response(JSON.stringify({ translation: translatedCode }), {
+		status: 200,
+		headers: { ...corsHeaders, 'Content-Type': 'application/json' },
+	});
+}
+
+async function handleExplain(request: Request, model: ReturnType<GoogleGenerativeAI['getGenerativeModel']>) {
+	const { code } = await request.json<{ code: string }>();
+
+	if (!code) {
+		return new Response(JSON.stringify({ error: "Missing 'code' in request body." }), {
+			status: 400,
+			headers: { ...corsHeaders, 'Content-Type': 'application/json' },
+		});
+	}
+
+	const prompt = `Explain the following code snippet in detail:
 1. Provide a clear breakdown of what each part (functions, variables, logic blocks) does.
 2. If applicable, describe the overall purpose or intent of the code.
 3. Offer a step-by-step explanation of how the code executes.
@@ -70,24 +57,35 @@ ${code}`;
 Code:
 ${code}`;
 
-				const result = await model.generateContent(prompt);
-				const explanation = result.response.text();
+	const result = await model.generateContent(prompt);
+	const explanation = result.response.text();
 
-				return new Response(JSON.stringify({ explanation }), {
-					status: 200,
-					headers: { ...corsHeaders, 'Content-Type': 'application/json' },
-				});
-			};
-			if (path === '/') {
-				return handleTranslate();
-			}
-			if (path === '/v1/translate') {
-				return handleTranslate();
+	return new Response(JSON.stringify({ explanation }), {
+		status: 200,
+		headers: { ...corsHeaders, 'Content-Type': 'application/json' },
+	});
+}
+
+export default {
+	async fetch(request: Request, env: Env, ctx: ExecutionContext): Promise<Response> {
+		if (request.method === 'OPTIONS') {
+			return new Response(null, { headers: corsHeaders });
+		}
+
+		try {
+			const url = new URL(request.url);
+			const path = url.pathname;
+			const genAI = new GoogleGenerativeAI(env.GEMINI_API_KEY);
+			const model = genAI.getGenerativeModel({ model: 'gemini-2.0-flash' });
+
+			if (path === '/' || path === '/v1/translate') {
+				return await handleTranslate(request, model);
 			}
+
 			if (path === '/v1/explain') {
-				return handleExplain();
+				return await handleExplain(request, model);
 			}
-			// Fallback for unknown paths
+
 			return new Response(JSON.stringify({ error: 'Route not found.' }), {
 				status: 404,
 				headers: { ...corsHeaders, 'Content-Type': 'application/json' },