import { RelayContext } from "@shared/relayProvider";

import { READONLY_RELAYS } from "@stores/constants";

import { getChannel, updateChannelMetadata } from "@utils/storage";

import { useContext } from "react";
import useSWR, { useSWRConfig } from "swr";
import useSWRSubscription from "swr/subscription";

const fetcher = async ([, id]) => {
	const result = await getChannel(id);
	if (result) {
		return result;
	} else {
		return null;
	}
};

export function useChannelProfile(id: string, channelPubkey: string) {
	const pool: any = useContext(RelayContext);

	const { mutate } = useSWRConfig();
	const { data, isLoading } = useSWR(["channel-metadata", id], fetcher);

	useSWRSubscription(
		!isLoading && data ? ["channel-metadata", id] : null,
		([, key]) => {
			// subscribe to channel
			const unsubscribe = pool.subscribe(
				[
					{
						"#e": [key],
						authors: [channelPubkey],
						kinds: [41],
					},
				],
				READONLY_RELAYS,
				(event: { content: string }) => {
					// update in local database
					updateChannelMetadata(key, event.content);
					// revaildate
					mutate(["channel-metadata", key]);
				},
				undefined,
				undefined,
				{
					unsubscribeOnEose: true,
				},
			);

			return () => {
				unsubscribe();
			};
		},
	);

	return data;
}