import { useCallback, useEffect, useState } from "react";
import type { ApiResult } from "@/lib/client/fetch-json";
import { inviteLinkAccept, inviteLinkGet, type InviteAcceptResult, type InviteLinkSummary } from "@/lib/client/invite-links";

function isError<T>(result: ApiResult<T>): result is { error: { code: string; message: string } } {
    return "error" in result;
}

export default function useInviteLink(token: string | null) {
    const [link, setLink] = useState<InviteLinkSummary | null>(null);
    const [loading, setLoading] = useState(false);
    const [accepting, setAccepting] = useState(false);
    const [error, setError] = useState("");
    const [result, setResult] = useState<InviteAcceptResult | null>(null);

    const load = useCallback(async () => {
        if (!token) {
            setLink(null);
            setError("");
            setResult(null);
            return;
        }
        setLoading(true);
        setError("");
        setResult(null);
        const response = await inviteLinkGet(token);
        if (isError(response)) {
            setError(response.error.message || "");
            setLink(null);
        } else {
            setLink(response.data.link);
        }
        setLoading(false);
    }, [token]);

    const accept = useCallback(async () => {
        if (!token) return null;
        setAccepting(true);
        setError("");
        const response = await inviteLinkAccept(token);
        if (isError(response)) {
            setError(response.error.message || "");
            setAccepting(false);
            return null;
        }
        setResult(response.data.result);
        setAccepting(false);
        return response.data.result;
    }, [token]);

    useEffect(() => {
        load();
    }, [load]);

    return {
        link,
        loading,
        accepting,
        error,
        result,
        accept,
        reload: load
    };
}