"use strict";

const express = require("express");
const path = require("path");
const { getDb } = require("./database");

const authRoutes = require("./routes/auth");
const profileRoutes = require("./routes/profile");
const programRoutes = require("./routes/program");

const app = express();
const PORT = parseInt(process.env.PORT, 10) || 3000;
const startTime = Date.now();

app.disable("x-powered-by");

// Body parsing
app.use(express.json());
app.use(express.urlencoded({ extended: true }));

// Static files
app.use(express.static(path.join(__dirname, "public")));

// Initialize database on startup
getDb();

// Health & readiness probes (Kubernetes)
app.get("/health", (_req, res) => {
  res.json({
    status: "healthy",
    uptime: Math.floor((Date.now() - startTime) / 1000),
    timestamp: new Date().toISOString(),
    memoryUsage: process.memoryUsage().rss,
  });
});

app.get("/ready", (_req, res) => {
  try {
    getDb();
    res.json({ ready: true });
  } catch (err) {
    res.status(503).json({ ready: false, error: err.message });
  }
});

// API routes
app.use("/api/auth", authRoutes);
app.use("/api/profile", profileRoutes);
app.use("/api/program", programRoutes);

// SPA fallback - serve index.html for non-API routes
app.get("*", (req, res) => {
  if (req.path.startsWith("/api/")) {
    return res.status(404).json({ error: "API endpoint bulunamadı" });
  }
  res.sendFile(path.join(__dirname, "public", "index.html"));
});

// 404 handler for API
app.use((req, res) => {
  res.status(404).json({ error: "Bulunamadı" });
});

// Error handler
app.use((err, _req, res, _next) => {
  console.error("Unhandled error:", err.message);
  res.status(500).json({ error: "Sunucu hatası" });
});

const server = app.listen(PORT, "0.0.0.0", () => {
  console.log(`health-app listening on port ${PORT}`);
});

function shutdown(signal) {
  console.log(`${signal} received, shutting down gracefully`);
  server.close(() => process.exit(0));
  setTimeout(() => process.exit(1), 10000);
}

process.on("SIGTERM", () => shutdown("SIGTERM"));
process.on("SIGINT", () => shutdown("SIGINT"));