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

const root = path.resolve(__dirname, "..");
const port = Number(process.env.PORT || process.env.CONFIG_SMS_FRIEND_BRIDGE_PORT || 5174);

function normalizeText(value) {
  return typeof value === "string" ? value.trim() : value ? String(value).trim() : "";
}

function parseEnvValue(value) {
  const text = normalizeText(value);
  if (
    (text.startsWith('"') && text.endsWith('"')) ||
    (text.startsWith("'") && text.endsWith("'"))
  ) {
    return text.slice(1, -1);
  }
  return text;
}

function loadEnvFile(fileName) {
  const filePath = path.join(root, fileName);
  if (!fs.existsSync(filePath)) return {};
  const env = {};
  const content = fs.readFileSync(filePath, "utf8");
  for (const line of content.split(/\r?\n/)) {
    const trimmed = line.trim();
    if (!trimmed || trimmed.startsWith("#")) continue;
    const index = trimmed.indexOf("=");
    if (index <= 0) continue;
    env[trimmed.slice(0, index).trim()] = parseEnvValue(trimmed.slice(index + 1));
  }
  return env;
}

const fileEnv = {
  ...loadEnvFile(".env"),
  ...loadEnvFile(".env.development"),
};

const mimeTypes = {
  ".html": "text/html; charset=utf-8",
  ".css": "text/css; charset=utf-8",
  ".js": "application/javascript; charset=utf-8",
  ".json": "application/json; charset=utf-8",
  ".png": "image/png",
  ".jpg": "image/jpeg",
  ".jpeg": "image/jpeg",
  ".svg": "image/svg+xml",
};

function sendText(res, text, contentType) {
  res.writeHead(200, {
    "Content-Type": contentType,
  });
  res.end(text);
}

function sendFile(res, filePath) {
  const ext = path.extname(filePath);
  res.writeHead(200, {
    "Content-Type": mimeTypes[ext] || "application/octet-stream",
  });
  fs.createReadStream(filePath).pipe(res);
}

function resolveAssetPath(urlPath) {
  const cleanPath = decodeURIComponent(urlPath.split("?")[0]);
  const assetPath = cleanPath.replace(/^\/sms\//, "/");
  const candidate = path.resolve(root, assetPath.replace(/^\/+/, ""));
  if (!candidate.startsWith(root)) return "";
  return candidate;
}

const server = http.createServer((req, res) => {
  const urlPath = (req.url || "/").split("?")[0];
  if (urlPath === "/config.js" || urlPath === "/sms/config.js") {
    const apiBase =
      process.env.api_url ||
      fileEnv.api_url ||
      "";
    sendText(
      res,
      `window.api_url=${JSON.stringify(apiBase)};\n`,
      "application/javascript; charset=utf-8",
    );
    return;
  }

  const assetPath = resolveAssetPath(req.url || "/");
  if (assetPath && fs.existsSync(assetPath) && fs.statSync(assetPath).isFile()) {
    sendFile(res, assetPath);
    return;
  }

  sendFile(res, path.join(root, "index.html"));
});

server.listen(port, () => {
  console.log(`Friend bridge H5 running at http://localhost:${port}/sms/{id}`);
});