const express = require("express");
const puppeteer = require("puppeteer-core");

const app = express();
app.use(express.json());

// CORS — allow requests from any frontend
app.use((req, res, next) => {
  res.header("Access-Control-Allow-Origin", "*");
  res.header("Access-Control-Allow-Headers", "Content-Type");
  res.header("Access-Control-Allow-Methods", "GET, POST, OPTIONS");
  if (req.method === "OPTIONS") return res.sendStatus(200);
  next();
});

const CF_ACCOUNT_ID = process.env.CF_ACCOUNT_ID;
const CF_API_TOKEN = process.env.CF_API_TOKEN;
const CF_MODEL = "@cf/meta/llama-3.1-8b-instruct";

app.get("/health", (req, res) => {
  res.json({ status: "ok" });
});

app.get("/debug", async (req, res) => {
  const hasAccountId = !!process.env.CF_ACCOUNT_ID;
  const hasToken = !!process.env.CF_API_TOKEN;

  let networkTest = "not attempted";
  try {
    const r = await fetch("https://api.cloudflare.com/client/v4/ips");
    networkTest = `reached Cloudflare, status ${r.status}`;
  } catch (err) {
    networkTest = `failed: ${err.message}`;
  }

  res.json({ hasAccountId, hasToken, networkTest });
});

async function getPlanFromAI(instruction) {
  const url = `https://api.cloudflare.com/client/v4/accounts/${CF_ACCOUNT_ID}/ai/run/${CF_MODEL}`;

  const response = await fetch(url, {
    method: "POST",
    headers: {
      Authorization: `Bearer ${CF_API_TOKEN}`,
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      messages: [
        {
          role: "system",
          content:
            'You convert a user\'s browsing instruction into a single JSON object: {"url": "<the website to visit>"}. ' +
            "Only output valid JSON, nothing else. If no clear URL or site is mentioned, guess the most likely official site.",
        },
        { role: "user", content: instruction },
      ],
    }),
  });

  const data = await response.json();

  if (!data.success) {
    throw new Error("Cloudflare AI error: " + JSON.stringify(data.errors));
  }

  const raw = data.result.response;
  try {
    return JSON.parse(raw);
  } catch {
    throw new Error("AI did not return valid JSON: " + raw);
  }
}

app.post("/run-task", async (req, res) => {
  const { instruction } = req.body;
  if (!instruction) return res.status(400).json({ error: "Missing 'instruction' in request body" });

  let plan;
  try {
    plan = await getPlanFromAI(instruction);
  } catch (err) {
    return res.status(502).json({ success: false, stage: "ai", error: err.message });
  }

  if (!plan.url) {
    return res.status(502).json({ success: false, error: "AI plan missing 'url'", plan });
  }

  let browser;
  try {
    browser = await puppeteer.launch({
      executablePath: process.env.PUPPETEER_EXECUTABLE_PATH,
      args: ["--no-sandbox", "--disable-setuid-sandbox"],
      headless: true,
    });

    const page = await browser.newPage();
    await page.goto(plan.url, { waitUntil: "domcontentloaded", timeout: 30000 });
    const title = await page.title();

    res.json({ success: true, instruction, plan, title });
  } catch (err) {
    res.status(500).json({ success: false, stage: "puppeteer", error: err.message });
  } finally {
    if (browser) await browser.close();
  }
});

const PORT = process.env.PORT || 7860;
app.listen(PORT, () => console.log(`Server running on port ${PORT}`));