import type { Observable } from 'rxjs'

declare const RxPostmessenger: Static
export default RxPostmessenger
export as namespace RxPostmessenger


export interface Static {
    /**
     * Create a new messenger for given window object. The remoteOrigin URL is used both to give to window.postMessage
     * calls on remoteWindow, and to filter inbound-message-events on the local window object.
     */
    connect(remoteWindow: Window, remoteOrigin: string): Messenger
}

export interface Messenger {

    /**
     * Returns an Observable that emits all incoming notifications for given notification-channel.
     */
    notifications<T = any>(channel: string): Observable<T>

    /**
     * Send a notification over given channel with given payload.
     */
    notify<T>(channel: string, payload?: T): void

    /**
     * Send a request over given channel with given payload. Returns an observable that will emit the response
     * and then complete.
     */
    request<T = any, U = any>(channel: string, payload?: T): Observable<U>

    /**
     * Returns an Observable that emits all incoming requests for given request-channel.
     */
    requests<T = any, U = any>(channel: string): Observable<Request<T, U>>
}

/**
 *
 */
export interface Request<T, U> {

    /**
     * The name of the channel the request was sent through. The
     * channel literal is immutable. Attempts to override the
     * channel property
     */
    readonly channel: string

    /**
     * The payload data for the request. The payload is immutable.
     * Attempts to set / override payload values will silently fail.
     * Attempts to mutate members of object-type payloads will
     * silently fail as well.
     */
    readonly payload: T

    /**
     * Boolean indicating whether respond() has been called on the request
     * previously.
     */
    readonly isHandled: boolean

    /**
     * The unique ID of the request.
     */
    readonly id: string

    /**
     * Respond to the request with given data.
     */
    respond(data: U): void
}