const express = require("express");
const cors = require("cors");
const axios = require("axios");
const helmet = require("helmet");
const path = require("path");

const app = express();
const PORT = process.env.PORT || 3001;

// Security headers
app.use(helmet());

// CORS (restrict in production)
app.use(
  cors({
    origin: process.env.CLIENT_URL || "*",
    methods: ["GET", "POST", "PUT", "DELETE", "OPTIONS"],
    allowedHeaders: ["Content-Type", "Authorization"],
  })
);

app.use(express.json({ limit: "50mb" }));
app.use(express.urlencoded({ extended: true, limit: "50mb" }));

// =============================
// Serve Frontend (React/Vite)
// =============================
app.use(
  express.static(path.join(__dirname, "dist"), {
    setHeaders: (res, filePath) => {
      if (filePath.endsWith(".js") || filePath.endsWith(".css")) {
        // Cache hashed assets for 1 year
        res.setHeader("Cache-Control", "public, max-age=31536000, immutable");
      } else {
        // Cache other assets (images, etc.) for 1 hour
        res.setHeader("Cache-Control", "public, max-age=3600");
      }
    },
  })
);

// SPA fallback → always return index.html
app.get("*", (req, res, next) => {
  if (req.path.startsWith("/api")) return next(); // skip API routes
  res.sendFile(path.join(__dirname, "dist", "index.html"));
});

// =============================
// Proxy /api requests
// =============================
app.use("/api", async (req, res, next) => {
  try {
    const url = `https://humanizerx.pro/api/routes.php${req.originalUrl.replace(
      "/api",
      ""
    )}`;
    const method = req.method.toLowerCase();

    const { data, status } = await axios({
      url,
      method,
      headers: {
        "Content-Type": req.headers["content-type"],
        Authorization: req.headers["authorization"],
      },
      data: req.body,
    });

    res.status(status).json(data);
  } catch (error) {
    console.error("API Proxy Error:", error.message);
    res.status(error.response?.status || 500).json({
      success: false,
      error: error.message,
    });
  }
});

// Test route
app.get("/test", (req, res) => {
  res.json({ msg: "Hello from Humanizer X backend 🚀" });
});

app.listen(PORT, () => {
  console.log(`✅ Humanizer X Backend running on http://localhost:${PORT}`);
});