import { TRPCError } from "@trpc/server";
import type Redis from "ioredis";
import puppeteer, { type PDFOptions } from "puppeteer-core";
import { env } from "~/env";
import type { AnnunciId } from "~/schemas/public/Annunci";
import type { OrdiniOrdineId } from "~/schemas/public/Ordini";
import type { TestiEStringheStingaId } from "~/schemas/public/TestiEStringhe";
import { getKeydbClient } from "~/utils/keydb";
import { TOKEN_CONFIG } from "../auth/configs";

export const SCHEDA_ANNUNCIO_CACHE_PREFIX = "scheda-annuncio-";
const CONDIZIONI_CACHE_PREFIX = "condizioni-";
export const invalidateCache = async (cacheKey: string) => {
	const keybd = getKeydbClient();
	if (keybd) {
		await keybd.del(cacheKey);
	}
};

async function deleteByPrefix(redis: Redis, prefix: string) {
	// Create a stream to find keys matching the pattern
	const stream = redis.scanStream({
		match: `${prefix}*`,
		count: 100, // Process 100 keys per iteration
	});

	stream.on("data", async (keys: string[]) => {
		if (keys.length > 0) {
			// Create a pipeline to delete keys in a single network round-trip
			const pipeline = redis.pipeline();

			// Use UNLINK instead of DEL for better performance on large keys
			keys.forEach((key) => pipeline.unlink(key));

			await pipeline.exec();
			console.log(`Deleted ${keys.length} keys`);
		}
	});

	stream.on("error", (err) => {
		console.error(
			`Error scanning/unlinking keys with prefix ${prefix}: ${err.message}`,
		);
	});
}

export const invalidateAllCaches = async () => {
	const keybd = getKeydbClient();
	if (keybd) {
		await deleteByPrefix(keybd, SCHEDA_ANNUNCIO_CACHE_PREFIX);
		await deleteByPrefix(keybd, CONDIZIONI_CACHE_PREFIX);
	}
};

export const getCacheStats = async () => {
	const keybd = getKeydbClient();
	if (keybd) {
		const schedaKeys = await keybd.keys(`${SCHEDA_ANNUNCIO_CACHE_PREFIX}*`);
		const condizioniKeys = await keybd.keys(`${CONDIZIONI_CACHE_PREFIX}*`);
		return {
			success: true,
			schedaCount: schedaKeys.length,
			condizioniCount: condizioniKeys.length,
		};
	}
	return {
		success: false,
		schedaCount: 0,
		condizioniCount: 0,
	};
};
export const genPdfSchedaAnnuncioBase64 = async (annuncioId: AnnunciId) => {
	const pdf = await genPdfSchedaAnnuncio(annuncioId);
	const pdfBase64 = Buffer.from(pdf).toString("base64");
	const base64Content = pdfBase64.includes("base64,")
		? pdfBase64.split("base64,")[1]
		: pdfBase64;
	if (!base64Content) {
		throw new Error("Failed to convert PDF to base64");
	}
	return base64Content;
};

export const genPdfSchedaAnnuncio = async (annuncioId: AnnunciId) => {
	const keybd = getKeydbClient();
	const url = `/area-riservata/scheda-annuncio-stampa/${annuncioId}?raw=true`;
	const options: PDFOptions = { printBackground: true };
	if (keybd) {
		const cacheKey = `${SCHEDA_ANNUNCIO_CACHE_PREFIX}${annuncioId}`;
		const cached = await keybd.get(cacheKey);
		if (cached) {
			return new Uint8Array(Buffer.from(cached, "base64"));
		}
		const scheda = await puppeteerGenPdf({
			url,
			options,
		});
		await keybd.set(
			cacheKey,
			Buffer.from(scheda).toString("base64"),
			"EX",
			3600 * 5,
		);
		return scheda;
	}
	return await puppeteerGenPdf({ url, options });
};

export const genPdfCondizioniBase64 = async (
	condizioniId: TestiEStringheStingaId,
) => {
	const pdf = await genPdfCondizioni(condizioniId);
	const pdfBase64 = Buffer.from(pdf).toString("base64");
	const base64Content = pdfBase64.includes("base64,")
		? pdfBase64.split("base64,")[1]
		: pdfBase64;
	if (!base64Content) {
		throw new Error("Failed to convert PDF to base64");
	}
	return base64Content;
};

const genPdfCondizioni = async (condizioniId: TestiEStringheStingaId) => {
	const keybd = getKeydbClient();
	const url = `/servizio/condizioni/${condizioniId}?raw=true`;
	if (keybd) {
		const cacheKey = `${CONDIZIONI_CACHE_PREFIX}${condizioniId}`;
		const cached = await keybd.get(cacheKey);
		if (cached) {
			return new Uint8Array(Buffer.from(cached, "base64"));
		}
		const scheda = await puppeteerGenPdf({ url });
		await keybd.set(
			cacheKey,
			Buffer.from(scheda).toString("base64"),
			"EX",
			3600 * 24 * 5,
		);
		return scheda;
	}
	return await puppeteerGenPdf({ url });
};

export const genPdfRicevutaCortesia = async (ordineId: OrdiniOrdineId) => {
	const url = `/servizio/ricevuta-cortesia/${ordineId}?raw=true`;
	return await puppeteerGenPdf({ url });
};

export const genPdfRicevutaCortesiaBase64 = async (
	ordineId: OrdiniOrdineId,
) => {
	const pdf = await genPdfRicevutaCortesia(ordineId);
	const pdfBase64 = Buffer.from(pdf).toString("base64");
	const base64Content = pdfBase64.includes("base64,")
		? pdfBase64.split("base64,")[1]
		: pdfBase64;
	if (!base64Content) {
		throw new Error("Failed to convert PDF to base64");
	}
	return base64Content;
};

const puppeteerGenPdf = async ({
	url,
	options,
}: {
	url: string;
	options?: PDFOptions;
}) => {
	let browser = null;

	try {
		browser = await puppeteer.connect({
			browserWSEndpoint: `${env.BROWSER_WS_URL}?--user-data-dir=/tmp/session-0`,
		});

		const page = await browser.newPage();

		const c = await browser.cookies();
		if (
			c.length === 0 ||
			!c.some(
				(cookie) => cookie.name === TOKEN_CONFIG.OVERRIDE_TOKEN_COOKIE_NAME,
			)
		) {
			const productionDomain = new URL(env.INTERNAL_BASE_URL).hostname;
			const newCookies = [
				{
					name: TOKEN_CONFIG.OVERRIDE_TOKEN_COOKIE_NAME,
					value: env.EXP_API_PASS,
					domain:
						env.NODE_ENV === "production"
							? productionDomain
							: "host.docker.internal",
					path: "/",
				},
			];
			await browser.setCookie(...newCookies);
		}

		const baseUrl =
			env.NODE_ENV === "production"
				? env.INTERNAL_BASE_URL
				: `http://host.docker.internal:3000`;

		const targetUrl = `${baseUrl}${url}`;
		try {
			await page.goto(targetUrl, { waitUntil: "networkidle2", timeout: 60000 });
		} catch (e) {
			if ((e as Error).message.includes("detached")) {
				await page.goto(targetUrl, { waitUntil: "load", timeout: 60000 });
			} else throw e;
		}

		const pdf = await page.pdf({
			format: "A4",
			...options,
		});
		return pdf;
	} catch (error) {
		throw new TRPCError({
			code: "INTERNAL_SERVER_ERROR",
			message: `Errore nella generazione del PDF, URL: ${url}, ${(error as Error).message}`,
		});
	} finally {
		// 'disconnect' tells browserless you're done with this tab
		if (browser) await browser.disconnect();
	}
};