const express = require("express");
const { exec } = require("child_process");
const os = require("os");
const path = require("path");
const multer = require("multer");
const fs = require("fs");
const axios = require("axios");

const app = express();
app.use(express.json());
app.use(express.static(path.join(__dirname)));

const MAX_MEM = 90;
const TIMEOUT = 60000;

const BLOCKED_COMMANDS = [
  "ollama", "docker build", "docker run", "python train",
  "cloudflared tunnel", "cloudflared tunnel --url",
  "cloudflared --url", "pip install torch", "yes", ":(){ :|:& }:"
];

let commandHistory = [];

// ===== MEMORY CHECK =====
function getMemoryUsage() {
  const total = os.totalmem();
  const free = os.freemem();
  return Math.round(((total - free) / total) * 100);
}

// ===== HOME PAGE =====
app.get("/", (req, res) => {
  res.sendFile(path.join(__dirname, "index.html"));
});

// ===== COMMAND EXECUTION =====
app.post("/run", (req, res) => {
  const cmd = req.body?.cmd || req.body?.command;
  if (!cmd) return res.json({ error: "command not provided" });

  console.log(`[RECEIVED]: ${cmd}`);

  if (cmd.trim().toLowerCase() === "log") {
    const historyText = commandHistory.length > 0
      ? commandHistory.map((item, i) => `${i + 1}. [${item.time}] ${item.command}`).join(" | ")
      : "History is empty.";

    return res.json({ output: historyText.replace(/\n/g, " "), error: "" });
  }

  if (cmd.trim().toLowerCase() === "clear") {
    commandHistory = [];
    return res.json({ output: "History cleared.", error: "" });
  }

  commandHistory.push({ time: new Date().toLocaleTimeString(), command: cmd });

  for (const blocked of BLOCKED_COMMANDS) {
    if (cmd.includes(blocked)) {
      return res.json({ error: "❌ Extremely heavy task blocked." });
    }
  }

  let finalCmd = cmd;
  if (cmd.startsWith("apt") && cmd.includes("install") && !cmd.includes("-y")) {
    finalCmd += " -y";
  }

  const memUsage = getMemoryUsage();
  if (memUsage > MAX_MEM) console.log(`⚠ High memory usage: ${memUsage}%`);

  exec(`timeout ${TIMEOUT / 1000} ${finalCmd}`, { maxBuffer: 5 * 1024 * 1024 }, (error, stdout, stderr) => {
    const cleanOutput = (stdout || "").replace(/\n/g, " ").trim();
    const cleanError = (stderr || "").replace(/\n/g, " ").trim();

    if (error && !stdout && !stderr) {
      return res.json({ error: error.message.replace(/\n/g, " ") });
    }

    res.json({ output: cleanOutput, error: cleanError });
  });
});

// ===== UPLOAD TO /app (ROOT) =====

// temp upload
const upload = multer({ dest: "temp/" });

app.post("/upload", upload.single("file"), (req, res) => {
  if (!req.file) {
    return res.json({ error: "No file uploaded" });
  }

  const targetPath = path.join(__dirname, req.file.originalname);

  fs.rename(req.file.path, targetPath, (err) => {
    if (err) {
      return res.json({ error: "Upload failed: " + err.message });
    }

    res.json({ output: `✅ File saved in /app as ${req.file.originalname}` });
  });
});

// ===== DOWNLOAD FROM /app =====
app.get("/download", (req, res) => {
  const filename = req.query.file;

  if (!filename) {
    return res.status(400).send("File name required");
  }

  const filePath = path.join(__dirname, filename);

  if (!fs.existsSync(filePath)) {
    return res.status(404).send("❌ File not found in /app");
  }

  res.download(filePath, filename, (err) => {
    if (err) {
      res.status(500).send("Download failed");
    }
  });
});

// ===== START SERVER =====
app.listen(7860, () => {
  console.log("Server running on port 7860");
});

// ===== AUTO LOG =====
const HF_URL = "http://localhost:7860/run";

setInterval(async () => {
  try {
    const res = await axios.post(HF_URL, { cmd: "log" });
    console.log("🔥 Auto log:", res.data.output || res.data);
  } catch (err) {
    console.error("⚠ Auto log error:", err.message);
  }
}, 120 * 60 * 1000);