import {Request, Response} from "express";
import {instace} from "./index.js";
interface ApiUrls {
	api: string;
	gateway: string;
	cdn: string;
	wellknown: string;
}

interface Invite {
	guild: {
		name: string;
		description?: string;
		icon?: string;
		id: string;
	};
	inviter?: {
		username: string;
	};
}

export async function getApiUrls(
	url: string,
	instances: instace[],
	check = true,
): Promise<ApiUrls | null> {
	if (!url.endsWith("/")) {
		url += "/";
	}
	if (check) {
		let valid = false;
		for (const instace of instances) {
			const urlstr = instace.url || instace.urls?.api;
			if (!urlstr) {
				continue;
			}
			try {
				if (new URL(urlstr).host === new URL(url).host) {
					valid = true;
					break;
				}
			} catch (e) {
				//console.log(e);
			}
		}
		if (!valid) {
			throw new Error("Invalid instance");
		}
	}
	try {
		const info: ApiUrls = await fetch(`${url}.well-known/spacebar`).then((res) => res.json());
		const api = info.api;
		const apiUrl = new URL(api);
		const policies: any = await fetch(
			`${api}${apiUrl.pathname.includes("api") ? "" : "api"}/policies/instance/domains`,
		).then((res) => res.json());
		return {
			api: policies.apiEndpoint,
			gateway: policies.gateway,
			cdn: policies.cdn,
			wellknown: url,
		};
	} catch (error) {
		console.error("Error fetching API URLs:", error);
		return null;
	}
}

export async function inviteResponse(
	req: Request,
	res: Response,
	instances: instace[],
): Promise<void> {
	let url: URL;
	try {
		url = new URL(req.query.url as string);
	} catch {
		const scheme = req.secure ? "https" : "http";
		const host = `${scheme}://${req.get("Host")}`;
		url = new URL(host);
	}

	try {
		if (!url.pathname.startsWith("invite") && !url.pathname.startsWith("/invite")) {
			throw new Error("Invalid invite URL");
		}

		const code = url.pathname.split("/")[2];
		const instance = url.searchParams.get("instance");
		if (!instance) {
			throw new Error("Instance not specified");
		}

		const urls = await getApiUrls(instance, instances);
		if (!urls) {
			throw new Error("Failed to get API URLs");
		}

		const invite = await fetch(`${urls.api}/invites/${code}`).then(
			(json) => json.json() as Promise<Invite>,
		);
		const title = invite.guild.name;
		const description = invite.inviter
			? `${invite.inviter.username} has invited you to ${invite.guild.name}${invite.guild.description ? `\n${invite.guild.description}` : ""}`
			: `You've been invited to ${invite.guild.name}${invite.guild.description ? `\n${invite.guild.description}` : ""}`;
		const thumbnail = invite.guild.icon
			? `${urls.cdn}/icons/${invite.guild.id}/${invite.guild.icon}.png`
			: "";

		res.json({
			type: "link",
			version: "1.0",
			title,
			thumbnail,
			description,
		});
	} catch (error) {
		//console.error("Error processing invite response:", error);
		res.json({
			type: "link",
			version: "1.0",
			title: "Jank Client",
			thumbnail: "/logo.webp",
			description: "A spacebar client that has DMs, replying and more",
			url: url.toString(),
		});
	}
}