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 CJS bundle, we check cwd first (PM2 working directory)
  const cwdDistPath = path.resolve(process.cwd(), "dist", "public");
  if (fs.existsSync(cwdDistPath)) {
    app.use(express.static(cwdDistPath));
    app.use("/{*path}", (_req, res) => {
      res.sendFile(path.resolve(cwdDistPath, "index.html"));
    });
    return;
  }

  // Fallback: check relative to this file
  const bundleDistPath = path.resolve(__dirname, "..", "public");
  if (fs.existsSync(bundleDistPath)) {
    app.use(express.static(bundleDistPath));
    app.use("/{*path}", (_req, res) => {
      res.sendFile(path.resolve(bundleDistPath, "index.html"));
    });
    return;
  }

  throw new Error(
    `Could not find the build directory. Checked: ${cwdDistPath}, ${bundleDistPath}`,
  );
}