import { Subject } from "../observe/Observable";
import { Model } from "./AbstractModel";
import { Observer } from "../observe/Observer";
import { fetchErrorHandler } from "./FetchErrorHandler";
import { ActiveUserViewModel } from "../viewmodel/ActiveUserViewModel";
import { JsonAPI } from "../singleton/JsonAPI";
import { ChatMessageViewModel } from "../viewmodel/ChatMessageViewModel";
import * as log from "loglevel";

export class UserModel implements Subject {
    /**
  * @type {Observer[]} List of subscribers. In real life, the list of
  * subscribers can be stored more comprehensively (categorized by event
  * type, etc.).
  */
    private readonly observers: Observer[] = [];
    private state: ActiveUserViewModel[] | undefined;
    // @ts-ignore: Cannot find name 'hostAddress'.

    constructor() { }
    /**
     * The subscription management methods.
     */
    public attach(observer: Observer): void {
        console.log('Subject: Attached an observer.');
        this.observers.push(observer);
    }

    public detach(observer: Observer): void {
        const observerIndex = this.observers.indexOf(observer);
        this.observers.splice(observerIndex, 1);
        console.log('Subject: Detached an observer.');
    }

    /**
     * Trigger an update in each subscriber.
     */
    public notify(): void {
        console.log('Subject: Notifying observers...');
        for (const observer of this.observers) {
            observer.update(this.state);
        }
    }

    public someBusinessMethod(activeuserList: ActiveUserViewModel[]): void {
        this.state = activeuserList;
        this.helperMethod();
        console.log(`Subject: My state has just changed`);
        console.log(activeuserList);
        this.notify();
    }

    /**
     * getActiveUsers
     */
    public getActiveUsers(): void {
        if(JsonAPI.authToken!= null){
        this.getActiveUsersAjax(JsonAPI.authToken, JsonAPI.ACTIVE_USERS_GET)
            .then(data => {
                // // activeUsers = data;
                // sessionStorage.setItem('activeUsers', JSON.stringify(data));
                // console.log(sessionStorage.getItem('activeUsers'));
                console.log(`Subject: received ajax active users`);
                this.state = data;
                this.notify();
            })
        }
        else {
            log.error('Auth token is null');
        }
    }

    async getActiveUsersAjax(authToken2: string, URL: string): Promise<any> {
        let headers = new Headers();
        // headers.append('Authorization', basicAuthToken);
        headers.append('X-AUTH-TOKEN', authToken2);
        let response = await fetch(JsonAPI.ACTIVE_USERS_GET, {
            method: 'GET',
            headers: headers
        });
        console.log(response.clone());
        if (fetchErrorHandler(response.clone())) {
            return null;
        }
        let data = await response.json();
        // return data;
        return new Promise((resolve, reject) => {
            if (data != null)
                resolve(data)
            else
                reject('Response data null')
        })
    }

    private helperMethod() { }

}