import "dotenv/config";
import express from "express";
import { chromium, Browser } from "playwright";
import { crawlPage } from "./lib/crawler";
import { chunkData } from "./lib/chunker";
import { formatAnalysisForPrompt, buildWebsitePrompt } from "./lib/ai-prompt";
import { generateWebsite } from "./lib/llm";
import { crawlQueue } from "./lib/queue";
import { parseGeneratedFiles } from "./lib/file-parser";
import { writeProjectFiles } from "./lib/project-writer";
import { validateAndSave } from "./lib/validator";

const API_KEY = process.env.CRAWL_API_KEY || "d3v-crawl-server-key-2026";
const PORT = Number(process.env.PORT) || 7860;
const HOST = "0.0.0.0";

let browser: Browser | undefined;

async function launchBrowser(): Promise<Browser> {
  console.log("Launching Chromium in-process...");
  return chromium.launch({
    headless: true,
    args: ["--no-sandbox", "--disable-dev-shm-usage", "--disable-gpu"],
  });
}

async function ensureBrowser(): Promise<Browser> {
  if (!browser || !browser.isConnected()) {
    browser = await launchBrowser();
  }
  return browser;
}

function withTimeout<T>(promise: Promise<T>, ms: number, label: string): Promise<T> {
  return Promise.race([
    promise,
    new Promise<never>((_, reject) =>
      setTimeout(() => reject(new Error(`${label} timed out after ${ms}ms`)), ms)
    ),
  ]);
}

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

app.use((req, res, next) => {
  if (req.path === "/health") return next();
  const auth = req.headers.authorization;
  if (auth !== `Bearer ${API_KEY}`) return res.status(401).json({ error: "unauthorized" });
  next();
});

app.get("/crawl", async (req, res) => {
  const url = req.query.url as string;
  if (!url) return res.status(400).json({ error: "url query param required" });

  try {
    const result = await crawlQueue.run(async () => {
      const b = await ensureBrowser();
      return crawlPage(b, url);
    });
    const out = req.query.chunked === "true" ? chunkData(result) : result;
    res.json(out);
  } catch (err: any) {
    res.status(500).json({ error: err.message });
  }
});

app.post("/build", async (req, res) => {
  const { prompt, reference, validate } = req.body || {};
  if (!prompt) return res.status(400).json({ error: "prompt is required" });

  try {
    let analysisText: string | undefined;

    if (reference) {
      console.log("[build] starting crawl of", reference);
      try {
        const crawled = await withTimeout(
          crawlQueue.run(async () => {
            const b = await ensureBrowser();
            return crawlPage(b, reference);
          }),
          70000,
          "crawl"
        );
        console.log("[build] crawl finished");
        analysisText = formatAnalysisForPrompt(crawled);
      } catch (err: any) {
        console.log("[build] crawl failed/timed out, continuing without reference:", err.message);
      }
    }

    const fullPrompt = buildWebsitePrompt(prompt, analysisText);
    console.log("[build] calling LLM...");
    const rawResult = await generateWebsite(fullPrompt);
    console.log("[build] LLM call finished, length:", rawResult.length);

    const files = parseGeneratedFiles(rawResult);

    if (files.length === 0) {
      res.json({ prompt, reference: reference || null, result: rawResult, files: [] });
      return;
    }

    const slug = prompt.toLowerCase().replace(/[^a-z0-9]+/g, "-");
    const { projectDir, written } = writeProjectFiles(files, slug);

    let validation = null;
    if (validate) {
      console.log("[build] validating (npm install + npm run build)...");
      validation = await validateAndSave(projectDir);
      console.log("[build] validation finished, success:", validation.success);
    }

    res.json({ prompt, reference: reference || null, projectDir, files: written, validation });
  } catch (err: any) {
    res.status(500).json({ error: err.message });
  }
});

app.get("/health", (_, res) => {
  res.json({ status: "ok", browserConnected: browser ? browser.isConnected() : false });
});

async function start() {
  await ensureBrowser();
  app.listen(PORT, HOST, () => console.log(`API server alive on http://${HOST}:${PORT}`));
}

async function shutdown() {
  console.log("Shutting down API server and closing browser...");
  if (browser) await browser.close();
  process.exit(0);
}

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

start();