declare enum ReadyState {CONNECTING = 0, OPEN = 1, CLOSED = 2}

export class EventSourcePolyfill extends EventTarget {
    CONNECTING: ReadyState;
    OPEN: ReadyState;
    CLOSED: ReadyState;

    constructor(url: string, eventSourceInitDict?: EventSourceInit);

    url: string;
    readyState: ReadyState;
    onopen: Function;
    onmessage: (event: OnMessageEvent) => void;
    onerror: Function;
    update: (options: EventSourceInit) => void;
    close: () => void;
}

interface EventSourceInit {
    withCredentials?: boolean;
    headers?: Object;
    errorOnTimeout?: boolean;
    heartbeatTimeout?: number;
    checkActivity?: boolean;
    connectionTimeout?: number;
}

interface OnMessageEvent {
    data: string;
}