app.js

import express from "express";
import fs from "fs/promises";
import { fileURLToPath } from "url";
import path from "path";

const app = express();
const PORT = process.env.PORT || 4000;
const defaultState = { cards: [], dependencies: [] };

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);
const DATA_PATH = path.join(__dirname, "data", "boardState.json");
await fs.mkdir(path.dirname(DATA_PATH), { recursive: true });

app.use(express.json());

// Statische Dateien mit Caching
app.use(
  express.static(path.join(__dirname, "public"), {
    maxAge: "1d",
    immutable: true,
  })
);

// Datenordner-Initialisierung
const initDataDir = async () => {
  try {
    await fs.access(path.dirname(DATA_PATH));
  } catch {
    await fs.mkdir(path.dirname(DATA_PATH), { recursive: true });
    await fs.writeFile(DATA_PATH, JSON.stringify(defaultState));
  }
};

// API-Endpunkte
app.get("/load-board", async (req, res) => {
  try {
    const data = await fs.readFile(DATA_PATH, "utf-8");
    const parsed = JSON.parse(data);
    res.status(200).json({
      cards: Array.isArray(parsed.cards) ? parsed.cards : [],
      dependencies: Array.isArray(parsed.dependencies)
        ? parsed.dependencies
        : [],
    });
  } catch (error) {
    res.status(200).json(defaultState);
  }
});

app.post("/save-board", async (req, res) => {
  if (!req.body || typeof req.body !== "object") {
    return res.status(400).json("Ungültige Anfragedaten");
  }

  const toSave = {
    cards: Array.isArray(req.body.cards) ? req.body.cards : [],
    dependencies: Array.isArray(req.body.dependencies)
      ? req.body.dependencies
      : [],
  };

  try {
    await fs.writeFile(DATA_PATH, JSON.stringify(toSave, null, 2));
    res.status(200).json({ message: "Board-Zustand gespeichert" });
  } catch (error) {
    res.status(500).json("Speichervorgang fehlgeschlagen");
  }
});

app.post("/reset-board", async (req, res) => {
  try {
    await fs.writeFile(DATA_PATH, JSON.stringify(defaultState, null, 2));
    res.status(200).json({ message: "Board zurückgesetzt" });
  } catch (error) {
    res.status(400).json("Zurücksetzen fehlgeschlagen");
  }
});

app.use(function (req, res, next) {
  if (req.originalUrl && req.originalUrl.split("/").pop() === "favicon.ico") {
    return res.status(204).end();
  }
  next();
});

// Client-Side Routing
app.get("/", (req, res) => {
  res.sendFile(path.join(__dirname, "public", "index.html"));
});
app.get("*", (req, res) => {
  res.sendFile(path.join(__dirname, "public", req.path));
});

// Serverstart
const server = app.listen(PORT, async () => {
  await initDataDir();
  console.log(`Server läuft auf Port ${PORT}`);
});

// Graceful Shutdown
const gracefulShutdown = (signal) => {
  console.log(`${signal} empfangen, Server wird beendet`);
  server.close(() => process.exit(0));
};

["SIGINT", "SIGTERM"].forEach((signal) => {
  process.on(signal, () => gracefulShutdown(signal));
});