import express from 'express';
import type { Express } from 'express';
import fs from "node:fs";
import path from "node:path";

export function serveStatic(app: Express) {
  // In production, dist/public is at the same level as index.cjs
  const distPath = path.resolve(__dirname, "..", "public");
  if (!fs.existsSync(distPath)) {
    // Fallback: check cwd
    const cwdPath = path.resolve(process.cwd(), "dist", "public");
    if (fs.existsSync(cwdPath)) {
      app.use(express.static(cwdPath));
      app.use("/{*path}", (_req, res) => {
        res.sendFile(path.resolve(cwdPath, "index.html"));
      });
      return;
    }
    throw new Error(
      `Could not find the build directory: ${distPath}, make sure to build the client first`,
    );
  }

  app.use(express.static(distPath));

  // fall through to index.html if the file doesn't exist
  app.use("/{*path}", (_req, res) => {
    res.sendFile(path.resolve(distPath, "index.html"));
  });
}