// Simple local dev server — serves frontend on http://localhost:3000
// Usage: node serve.js          (uses config.js — points to deployed API)
//        node serve.js --local   (uses config.local.js — points to SAM local on :3001)

const http = require("http");
const fs = require("fs");
const path = require("path");

const PORT = 3000;
const DIR = __dirname;
const LOCAL_MODE = process.argv.includes("--local");

const MIME = {
  ".html": "text/html",
  ".js":   "application/javascript",
  ".css":  "text/css",
  ".json": "application/json",
  ".png":  "image/png",
  ".svg":  "image/svg+xml",
  ".ico":  "image/x-icon",
};

http.createServer((req, res) => {
  let url = req.url.split("?")[0];
  if (url === "/") url = "/login.html";

  // In local mode, serve config.local.js when config.js is requested
  if (LOCAL_MODE && url === "/config.js") {
    url = "/config.local.js";
  }

  const filePath = path.join(DIR, url);
  const ext = path.extname(filePath);

  fs.readFile(filePath, (err, data) => {
    if (err) {
      res.writeHead(404);
      res.end("Not found");
      return;
    }
    res.writeHead(200, { "Content-Type": MIME[ext] || "application/octet-stream" });
    res.end(data);
  });
}).listen(PORT, () => {
  const mode = LOCAL_MODE ? "LOCAL (API → localhost:3001)" : "DEPLOYED (API → production)";
  console.log(`\n  LedgerFlow frontend: http://localhost:${PORT}  [${mode}]\n`);
});