gsender

import fs from "fs";
import path from "path";

export const viteServer = async (app) => {
	const isProduction = process.env.NODE_ENV === "production";
	const base = process.env.BASE || "/";
	const bundleRoot = path.resolve(__dirname, "..");
	const projectRoot = process.cwd();

	const devDir = path.resolve(projectRoot, "src/app");
	const prodDirCandidates = [
		path.resolve(bundleRoot, "app"),
		path.resolve(projectRoot, "dist/gsender/app"),
	];
	const prodDir =
		prodDirCandidates.find((dir) => fs.existsSync(dir)) || prodDirCandidates[0];

	if (!isProduction && !fs.existsSync(devDir)) {
		throw new Error(`Vite dev directory not found: ${devDir}`);
	}

	// Cached production index.html (optional — graceful if missing)
	let templateHtml = "";
	if (isProduction) {
		const indexPath = path.resolve(prodDir, "index.html");
		if (fs.existsSync(indexPath)) {
			templateHtml = await fs.promises.readFile(indexPath, "utf-8");
		}
	}

	if (!isProduction) {
		const { createServer } = await import("vite");
		const vite = await createServer({
			server: { middlewareMode: true },
			appType: "spa", // handles SPA routing + index.html fallback automatically
			base,
			configFile: path.resolve(devDir, "vite.config.js"),
		});
		app.use(vite.middlewares);
	} else {
		const compression = (await import("compression")).default;
		const sirv = (await import("sirv")).default;
		app.use(compression());
		app.use(base, sirv(path.resolve(prodDir), { extensions: [] }));

		// SPA fallback for prod: serve index.html for all unmatched routes
		app.use("*", (req, res) => {
			if (templateHtml) {
				res.status(200).set({ "Content-Type": "text/html" }).send(templateHtml);
			} else {
				res.status(404).end("Not found");
			}
		});
	}
};