import { useEffect } from "react";
import ReconnectingEventSource from "reconnecting-eventsource";
import { devlog } from "../utils";


export function useSSESubscription<T>({ enabled = true, url, onNewData, onDisconnect, marker = "" }: {
    enabled?: boolean;
    url: string;
    onNewData: (data: T[]) => void;
    onDisconnect: () => void;
    marker?: string;
}) {
    useEffect(() => {
        if (!enabled) return;

        const eventSource = new ReconnectingEventSource(url);

        eventSource.addEventListener("open", () => devlog(`EventSource connected with ${url}`));
        eventSource.addEventListener("close", () => devlog(`EventSource closed with ${url}`));
        eventSource.addEventListener("message", event => {
            try {
                const newData = JSON.parse(event.data) as T;
                devlog(`new SSE: ${marker}`, newData);
                onNewData([newData]);
            } catch (error) {
                devlog(`SSE parsing error: ${marker}`, event.data, error);
            }
        });
        eventSource.addEventListener("error", event => {
            devlog("SSE Error:", event);
        });

        return () => {
            eventSource.close();
            onDisconnect();
        };
    }, [enabled, marker, onDisconnect, onNewData, url]);
}