const UA =
	"Mozilla/5.0 (Windows NT 10.0; Win64; x64) " +
	"AppleWebKit/537.36 (KHTML, like Gecko) " +
	"Chrome/125.0.0.0 Safari/537.36";

let browser: any = null;

async function getBrowser() {
	if (browser) return browser;
	const puppeteer = await import("puppeteer-extra");
	const StealthPlugin = await import("puppeteer-extra-plugin-stealth");
	puppeteer.default.use(StealthPlugin.default());
	browser = await puppeteer.default.launch({
		headless: true,
		args: [
			"--no-sandbox",
			"--disable-setuid-sandbox",
			"--disable-web-security",
			"--disable-blink-features=AutomationControlled",
			"--user-agent=" + UA,
		],
	});
	return browser;
}

export async function fetchWithCfBypass(
	url: string,
	timeout = 30000,
): Promise<string> {
	const b = await getBrowser();
	const page = await b.newPage();
	await page.setUserAgent(UA);
	await page.setDefaultTimeout(timeout);

	try {
		const response = await page.goto(url, {
			waitUntil: "networkidle2",
			timeout,
		});

		const status = response?.status() ?? 0;
		const body = await page.content();

		const isCfChallenge =
			body.includes("Attention Required") ||
			body.includes("Checking your browser") ||
			body.includes("Just a moment") ||
			body.includes("cf-challenge") ||
			status === 403;

		if (isCfChallenge) {
			await page.waitForFunction(
				() =>
					!document.body.innerHTML.includes("Attention Required") &&
					!document.body.innerHTML.includes("Checking your browser") &&
					!document.body.innerHTML.includes("Just a moment"),
				{ timeout: 10000 },
			);
		}

		const finalBody = await page.content();
		return finalBody;
	} finally {
		try {
			await page.close();
		} catch {
			// ignore cleanup errors
		}
	}
}

export async function fetchJsonWithCfBypass<T = unknown>(
	url: string,
	timeout = 30000,
): Promise<T> {
	const html = await fetchWithCfBypass(url, timeout);
	const match = html.match(
		/<pre[^>]*class="[^"]*json[^"]*"[^>]*>([\s\S]*?)<\/pre>/i,
	);
	if (match) {
		return JSON.parse(match[1].trim()) as T;
	}
	try {
		return JSON.parse(html) as T;
	} catch {
		throw new Error(`cf-fetch: could not parse JSON from ${url}`);
	}
}

export async function closeCfBrowser(): Promise<void> {
	if (browser) {
		try {
			await browser.close();
		} catch {
			// ignore cleanup errors
		}
		browser = null;
	}
}