import { createReadStream, existsSync } from "node:fs";
import { stat } from "node:fs/promises";
import { createServer } from "node:http";
import path from "node:path";
import { fileURLToPath } from "node:url";
import { attachDiceSyncServer } from "./dice-sync.mjs";

const serverDir = path.dirname(fileURLToPath(import.meta.url));
const distDir = path.resolve(serverDir, "../dist");
const port = Number(process.env.PORT || 3000);

const contentTypes = {
  ".css": "text/css; charset=utf-8",
  ".html": "text/html; charset=utf-8",
  ".ico": "image/x-icon",
  ".jpeg": "image/jpeg",
  ".jpg": "image/jpeg",
  ".js": "text/javascript; charset=utf-8",
  ".json": "application/json; charset=utf-8",
  ".png": "image/png",
  ".svg": "image/svg+xml",
  ".webp": "image/webp",
  ".woff": "font/woff",
  ".woff2": "font/woff2",
};

const sendFile = async (request, response, filePath) => {
  const fileStat = await stat(filePath);
  response.writeHead(200, {
    "Content-Type":
      contentTypes[path.extname(filePath)] || "application/octet-stream",
    "Content-Length": fileStat.size,
    "Cache-Control": filePath.endsWith("index.html")
      ? "no-cache"
      : "public, max-age=31536000, immutable",
  });
  if (request.method === "HEAD") response.end();
  else createReadStream(filePath).pipe(response);
};

const httpServer = createServer(async (request, response) => {
  try {
    const requestUrl = new URL(request.url || "/", "http://localhost");
    if (requestUrl.pathname === "/api/health") {
      response.writeHead(200, {
        "Content-Type": "application/json; charset=utf-8",
        "Cache-Control": "no-store",
      });
      response.end(JSON.stringify({ ok: true }));
      return;
    }
    if (!["GET", "HEAD"].includes(request.method || "")) {
      response.writeHead(405, { Allow: "GET, HEAD" });
      response.end("Method not allowed");
      return;
    }

    const decodedPath = decodeURIComponent(requestUrl.pathname);
    const requestedFile = path.resolve(distDir, `.${decodedPath}`);
    const safePath = requestedFile.startsWith(`${distDir}${path.sep}`)
      ? requestedFile
      : path.join(distDir, "index.html");
    let filePath = path.join(distDir, "404.html");
    if (existsSync(safePath)) {
      const safeStat = await stat(safePath);
      if (safeStat.isFile()) filePath = safePath;
      else if (
        safeStat.isDirectory() &&
        existsSync(path.join(safePath, "index.html"))
      )
        filePath = path.join(safePath, "index.html");
    }
    await sendFile(request, response, filePath);
  } catch {
    response.writeHead(500, { "Content-Type": "text/plain; charset=utf-8" });
    response.end("Internal server error");
  }
});

attachDiceSyncServer(httpServer);

httpServer.listen(port, "0.0.0.0", () => {
  console.log(`Interactives is listening on port ${port}`);
  if (
    typeof process.getuid === "function" &&
    process.getuid() === 0 &&
    typeof process.setuid === "function"
  ) {
    try {
      process.setuid("node");
    } catch {
      // The container can still run safely with its filesystem mounted read-only by the platform.
    }
  }
});

const shutdown = () => httpServer.close(() => process.exit(0));
process.on("SIGTERM", shutdown);
process.on("SIGINT", shutdown);